Stratno | Stratigraphic Name | Category | Contents | Last update 
21096|Abarungkwa Sandstone|Name source|Abarungkwa (GR PE335875), an aboriginal place name located on Bickerton Island, BLUE MUD BAY.|16-MAY-23
21096|Abarungkwa Sandstone|Unit history|Formerly mapped as part of the now abandoned 'Groote Eylandt beds' (Plumb and Roberts, 1965, 1992).|16-MAY-23
21096|Abarungkwa Sandstone|Geomorphic expression|Rugged, bare rocky ridges and coastal cliffs.|16-MAY-23
21096|Abarungkwa Sandstone|Type section locality|Lower boundary stratotype: Southern shoreline of North Bay on Bickerton Island (lat. 13o 45'S, long. 136o 10'E; GR PE260790); approximately 12 m of section exposed. Upper boundary locality: Covered interval at lat. 13o 46'S, long. 136o 09'E (GR PE250775). Reference locality: Isthmus between North Bay and South Bay on Bickerton Island, between lat. 13o 45' 00"S, long. 136o 10'E and lat. 13o 45' 45"S, long. 136o 10'E (GR PE260790 to PE260780).|16-MAY-23
21096|Abarungkwa Sandstone|Extent|Northern half of the Bickerton Island and on Bustard Island, BLUE MUD BAY.|16-MAY-23
21096|Abarungkwa Sandstone|Thickness range|Most complete section at reference section locality where it is estimated to be 100-150m thick.|16-MAY-23
21096|Abarungkwa Sandstone|Lithology|White, coarse- to very coarse-grained, cross-bedded, pebbly, quartz-rich (lithic at base) sandstone; quartz-rich granule conglomerate; polymict pebble and cobble conglmerate; minor medium-grained quartz sandstone.|16-MAY-23
21096|Abarungkwa Sandstone|Depositional environment|High-energy braided fluviatile.|16-MAY-23
21096|Abarungkwa Sandstone|Relationships and boundaries|Lies unconformably on Grindall Formation. Locally overlies Erringkarri Rhyolite with erosional contact; overlain by Bickerton Rhyolite in South Bay area. Where Bickerton Rhyolite is absent the present unit is disconformably overlain by valley-fill conglomerate of the Milyakburra Formation. On Bustard Island it is intruded by Bickerton Rhyolite.|16-MAY-23
21096|Abarungkwa Sandstone|Age reasons|Probably Orosirian (Palaeoproterozoic). The overlying Bickerton Rhyolite has been dated by SHRIMP single-zircon U-Pb techniques at ~1815 Ma (Pietsch et al. 1994).|16-MAY-23
21096|Abarungkwa Sandstone|Correlations|Considered to correlate with the ~1800-1840Ma felsic volcanic suite widespread in northern Australia (Rawlings, 1994).|16-MAY-23
71|Acacia Gap Quartzite Member|Name source|First defined by Malone (1962) who called it the Acacia Gap Tongue of the Masson Formation. Now considered to be a member of the Wildman Siltstone (Needham and Stuart-Smith, 1978), and previous name now considered inappropriate.|16-MAY-23
71|Acacia Gap Quartzite Member|Defn author|Redefined here by I. Crick in 1982|16-MAY-23
71|Acacia Gap Quartzite Member|Proposed publication|Bureau of Mineral Resources Report|16-MAY-23
28157|Adla Granulite|Name source|Adla Hill, at 23o26'S, 133o32'E, in the Alice Springs 1:250 000 Sheet area.|16-MAY-23
28157|Adla Granulite|Unit history|Previously mapped by Wells & others (1968) as undivided Arunta Complex.|16-MAY-23
28157|Adla Granulite|Type section locality|A small rise at 5651-518078 1.5 km east of Adla Hill.|16-MAY-23
28157|Adla Granulite|Extent|The unit forms isolated hills including Adla Hill and Boen Hill, west of Cottonbush Dam in the southwest corner of the Burt 1:100 000 Sheet area. Airphoto-lineaments and several small isolated exposures indicate that the unit extends as a 10 km wide, 25 km long belt under a veneer of Cainozoic deposits between the two hills.|16-MAY-23
28157|Adla Granulite|Lithology|Interlayered mafic granulite, and garnet-felsic granulite, both of which are partly retrogressed. The mafic granulite typical contains abundant quartz and hornblende, and small amounts of garnet. The felsic granulite contains a large proportion of coarse-grained quartz-orthoclase-plagioclase mobilisate. Some of the felsic granulite contains sillimanite.|16-MAY-23
28157|Adla Granulite|Relationships and boundaries|The isolated exposures are completely surrounded by Cainozoic cover.|16-MAY-23
28157|Adla Granulite|Age reasons|Mid-Proterozoic or older. Probably metamorphosed at 1800 m.y; the age of the main granulite metamorphism in the Strangways Metamorphic Complex in which it is included (Black, 1975; Iyer, Woodford & Wilson, 1976).|16-MAY-23
28157|Adla Granulite|Correlations|Correlated with the Yamba granulite and the Ongeva granulite of Strangways Metamorphic Complex.|16-MAY-23
24148|Adnera Member|Name source|Adnera Creek and Waterhole on Home of Bullion 1:100 000 Sheet (AMG GR MR185697).|16-MAY-23
24148|Adnera Member|Unit history|Upper part of PuCs2 unit of Shaw and Warren (1975) and Shaw et al. (1979).|16-MAY-23
24148|Adnera Member|Geomorphic expression|Commonly exposed as gently rounded range tops capping less resistant Tops Member.|16-MAY-23
24148|Adnera Member|Type section locality|30 km south-southwest of Stirling homestead on Barrow 1:100 000 sheet. Base of section at AMG GR LR677667 (latitude 22o00'00"S, longitude 133o43'05"E); top at GR LR682671 (latitude 21o59'47"S, longitude 133o43'23"E).|16-MAY-23
24148|Adnera Member|Extent|Southwest quarter of Barrow Creek, southeastern Mount Peake and northwestern Alcoota 1:250 000 sheets.|16-MAY-23
24148|Adnera Member|Thickness range|310 m at type section. 72 m measured at AMG GR MR015951 on Home of Bullion 1:100 000 sheet. Thickens towards the southwest.|16-MAY-23
24148|Adnera Member|Lithology|Medium-grained, white, feldspathic quartz arenite and orthoquartzite. Some granule horizons. Upper unit of red-brown sandstone and siltstone in some areas. Well developed cross-bedding. Rare trace fossils in upper unit.|16-MAY-23
24148|Adnera Member|Relationships and boundaries|Conformably overlies Tops Member. Base picked at first consistent development of white quartz arenite above underlying redbeds of Tops Member. Overlain with probable disconformity by Early Cambrian Octy Formation.|16-MAY-23
24148|Adnera Member|Structure and Metamorphism|Generally horizontal or gently dipping to southwest, except near faults.|16-MAY-23
24148|Adnera Member|Age reasons|Considered to be latest Proterozoic (late Adelaidean) as it conformably overlies the Tops Member which contains an element of the Ediacara Assemblage. Contains rare trace fossils but not distinctive Cambrian forms.|16-MAY-23
24148|Adnera Member|Correlations|May correlate in part with Andagera Formation to the northeast.|16-MAY-23
168|Aileron Metamorphics|Name source|Aileron (5552-295943), a settlement on Stuart Highway 135 km north of Alice Springs, Aileron 1:100 000 Sheet area.|16-MAY-23
168|Aileron Metamorphics|Type section locality|Reference area: Prominent hill at 5552-255996, 6.5 km northwest of Aileron; southeastern slope of hill shows gently dipping felsic and mafic banded granulites; towards top of hill, granulites are intimately; mixed with augen gneiss of Boothby Orthogneiss.|16-MAY-23
168|Aileron Metamorphics|Extent|Northeast part of Aileron 1:100 000 Sheet area; extends into Alcoota 1:250 000 Sheet area.|16-MAY-23
168|Aileron Metamorphics|Lithology|Ten sub-units recognised and mapped: 1. Felsic granulite, with smaller amounts of mafic granulite, amphibolite, garnet-biotite gneiss, sillimanite gneiss, cordierite granulite and gneiss; 2. Mafic granulite, with small amount of felsic granulite; 3. Cordierite gneiss; 4. Garnet-biotite gneiss, cordierite gneiss, mafic granulite; 5. Calc-silicate rock, forsterite marble; 6. Sillimanite-garnet-biotite gneiss, amphibolite, garnet amphibolite; 7. Quartz-rich metasediment; 8. Cordierite-garnet granulite; 9. Quartzofeldspathic gneiss; 10. Amphibolite.|16-MAY-23
168|Aileron Metamorphics|Relationships and boundaries|Forms large separate enclaves up to 4 km long in or adjacent to Boothby Orthogneiss; adjoins and intruded by northeast margin of Napperby Gneiss; in contact with and intruded by unnamed granite at 2 localities 4 and 7 km south of Aileron, respectively.|16-MAY-23
168|Aileron Metamorphics|Age reasons|No isotopic dates. Older than approximate date of 1100 m.y. on Boothby Orthogneiss (L.P. Black, BMR, pers. Comm., 1977), older than date of 1800-1500 m.y. on Napperby Gneiss (L.P.B., pers. Comm., 1975).|16-MAY-23
168|Aileron Metamorphics|Proposed publication|Commentary on Reynolds Range-Aileron 1:100 000 Special Map.|16-MAY-23
168|Aileron Metamorphics|Comments|Reason for Proposed Name:  Distinctive mappable rock-types.|16-MAY-23
27692|Albinia Formation|Name source|The name is derived from the Albinia Spring (6673:5195) situated on the Waite Creek in the western part of the Mount Doreen sheet area.|16-MAY-23
27692|Albinia Formation|Type section locality|The type section lies in the SW part of the Vaughan Springs Syncline (6825-5280:6836-5283).|16-MAY-23
27692|Albinia Formation|Extent|The Albinia Formation crops out in the Vaughan Springs Syncline and in a few poor outcrops on the northern flank of the basin in the Treuer Range.|16-MAY-23
27692|Albinia Formation|Thickness range|The thickness of the formation in the type section is about 150 m and is the thickest known section.|16-MAY-23
27692|Albinia Formation|Lithology|The formation is poorly exposed because of its high siltstone and shale content. The most characteristic rock type is a dark grey foetid dolomite with stromatolites, and white, grey and black chert.|16-MAY-23
27692|Albinia Formation|Relationships and boundaries|The Albinia Formation overlies the Adelaidean Vaughan Springs Quartzite probably disconformably and is unconformably overlain by the Adelaidean Mount Doreen Formation, and possibly by the Naburula Formation and Rinkabeena Shale Formation also unconformably.|16-MAY-23
27692|Albinia Formation|Age reasons|The lithology and stratigraphic position of the Albinia Formation indicate that it is probably Adelaidean in age. It is correlated with the Bitter Springs Formation in the Amadeus Basin.|16-MAY-23
27692|Albinia Formation|Comments|Reason for proposed name: The formation was originally thought to be part of the Mount Doreen Formation. It is now considered to be a separate unit and genetically unrelated to the Mount Doreen Formation.|16-MAY-23
39599|Alcurra Dolerite|Name source|Alcurra Creek, northern South Australia. Alberga 1:250,000 map sheet area|16-MAY-23
39599|Alcurra Dolerite|Unit history|Unit equivalent to Alcurra Dyke Swarm (Coates 1963, Edgoose et al 1993, Scrimgeour et al 1999, Young et al 2002, Edgoose et al 2002) and Kulgera Dyke Swarm (Camacho et al 1991). Synonymous with Alcurra dolerite (Close et al 2003).|16-MAY-23
39599|Alcurra Dolerite|Type section locality|Kulgera railway quarry, Kulgera 1:250,000 map sheet area. 26o 50' 20" S, 132o 23' 30" E.|16-MAY-23
39599|Alcurra Dolerite|Extent|Widespread across Musgrave Block as dykes, sills and less commomly bodies|16-MAY-23
39599|Alcurra Dolerite|Lithology|Pristine dolerite has an ophitic to sub-ophitic texture, and contains plagioclase, clinopyroxene, olivine, K feldspar, and minor quartz and opaques. In the southwestern Musgrave Block NT the dolerite has largely been recrystallised to metamorphic grades ranging from garnet granulite to garnet amphibolite facies. Amphibolite is fine-grained, dark greenish black, with equigranular hornblende and plagioclase, and locally garnet. Recystallised dykes that have not also been deformed contain kyanite within plagioclase, and garnet coronas around pyroxene, where they are in contact with plagioclase. Partly recrystallised dykes have garnet and secondary clinopyroxene which define the mylonitic fabric and form coronas on ortho- and clinopyroxene. Completely recrystallised dykes contain garnet, clinopyroxene, hornblende, sodic plagioclase, quartz and rutile, with or without scapolite. In greenschist facies, the dolerite has variably recrystallised to assemblages containing actinolite, chlorite and epidote.|16-MAY-23
39599|Alcurra Dolerite|Relationships and boundaries|Intrudes gneiss with protolith ages in the range 1600-1540 Ma; crosscuts gneissic fabric resulting from 1200-1160 Ma Musgrave Orogeny. Intrudes Pitjantjatjara Supersuite granite. Intruded by 1071 +/- 5 Ma Angatja Granite in eastern Musgrave Ranges (Scrimgeour et al 1999). Deformed and metamorphosed during the 570-530 Ma Petermann Orogeny.|16-MAY-23
39599|Alcurra Dolerite|Age reasons|1080 Ma interpreted age from correlation with mafic rocks of the 1080 Ma Giles Complex and constrained by 1071 +/- 5 Ma age for Angatja Granite which intrudes it. A Rb/Sr age of 1054 +/- 13 Ma was obtained for a dyke in the Kulgera area and a 1090 +/- 32 Ma Sm-Nd age was obtained for a dyke from the same area by Zhao and McCulloch (1993).|16-MAY-23
39599|Alcurra Dolerite|Correlations|Stuart Pass Dolerite of the southern Arunta Region, which has a Sm-Nd age of 1076 ? 33 Ma  (Zhao and McCulloch 1993).|16-MAY-23
39599|Alcurra Dolerite|Proposed publication|Edgoose et al 2003|16-MAY-23
39599|Alcurra Dolerite|References|*CAMACHO A, Simons B and Schmidt PW, 1991. Geological and palaeomagnetic significance of the Kulgera Dyke Swarm, Musgrave Block, NT, Australia. International Geophysical Journal 107, 37-45.      *CLOSE DF, Edgoose CJ and Scrimgeour IR, 2003. Hull and Bloods Range, Northern Territory. 1:100 000 geological map series explanatory notes, 4748, 4848. Northern Territory Geological Survey, Darwin.    *COATES RP 1963. The geology of the Alberga 4-mile military sheet, Explanation of the geological Map. South Australian Department of Mines and Energy, Geological Survey, Report of Investigations 22.    *EDGOOSE CJ, Camacho A, Wakelin-King, GA and Simons BA, 1993. Kulgera, Northern Territory (Second Edition). 1250 000 geological map series explanatory notes, SE 53-5. Northern Territory Geological Survey, Darwin.     *EDGOOSE CJ, Close DF, Stewart AJ and Duncan N, 2002. Umbeara, Northern Territory. 1:100 000 geological map series explanatory notes, 5646. Northern Territory Geological Survey, Darwin and Geoscience Australia, Canberra (National Geoscience Mapping Accord).    *EDGOOSE CJ, Scrimgeour IR and Close DF, 2003. Geology of the Musgrave Block, Northern Territory. Northern Territory Geological Survey, Report 15. **SCRIMGEOUR IR, Close DF and Edgoose CJ, 1999. Petermann Ranges, Northern Territory (Second Edition). 1:250 000 geological map series explanatory notes, SG 52-07. Northern Territory Geological Survey, Darwin.    *YOUNG DN, Duncan N, Camacho A, Ferenzi PA and Madigan TLA, 2002. Ayers Rock, Northern Territory (Second Edition). 1:250 000 geological map series explanatory notes, SG 52-08. Northern Territory Geological Survey, Darwin.     *ZHAO JX & McCulloch MT, 1993. Sm-Nd mineral isochron ages of Late Proterozoic dyke swarms in Australia: evidence for two distinctive events of mafic magmatism and crustal extension. Chemical Geology 109, 341-354.|16-MAY-23
24152|Ali Curung Granite|Name source|Ali Curung Aboriginal community (AMG GR MS380770) on the Taylor 1:100 000 Sheet (5755).|16-MAY-23
24152|Ali Curung Granite|Unit history|Previously mapped as an unnamed granite or as a quartz feldspar porphyry (Smith and Milligan, 1964).|16-MAY-23
24152|Ali Curung Granite|Geomorphic expression|Low, irregular hills and tors, widely separated inselbergs, rocky boulder strewn hills; smooth pale and dark air photo tones.|16-MAY-23
24152|Ali Curung Granite|Type section locality|Within 3 km radius of AMG GR MS000515 (latitude 21o14'98"S, longitude 134o02'10"E) in the northwestern part of the Taylor 1:100 000 Sheet. Pgaf and Pgac are present at this locality. For other phases see reference localities below.|16-MAY-23
24152|Ali Curung Granite|Extent|Northeastern part of the Crawford (5655) and western part of the Taylor 1:100 000 Sheets.|16-MAY-23
24152|Ali Curung Granite|Lithology|(different phases listed by map symbols): Undifferentiated granite around GR LS825663 (Pga): medium to coarse, with quartz-alkali feldspar-plagioclase (commonly sericitised) -muscovite+biotite, with accessory opaque oxides, zircon and apatite; some graphic intergrowths of quartz and feldspar; intrudes Hatches Creek Group at GR LS816669).  Granite (Pgaa): fine, even-grained, pinkish grey, with biotite (partly altered to chlorite) with zircon inclusions, muscovite, quartz with undulose extinction, partly sericitised plagioclase, alkali feldspar (perthite common with rare granophyric intergrowths of quartz, microcline less common), traces of epidote, apatite, sphene and opaque minerals (e.g. at GR MS115333). Granite (Pgab): medium porphyritic, grey, with biotite (commonly with zircon inclusions), muscovite, quartz with undulose extinction, plagioclase (partly sericitised), alkali feldspar (perthite common with rare granophyric intergrowths of quartz, microcline less common), accessory apatite, opaque minerals and tourmaline +/- sphene (e.g. at GR MS159302).  Granite (Pgac): medium to coarse, porphyritic, pale grey, with biotite partly altered to chlorite, quartz with undulose extinction, plagioclase partly altered to sericite+epidote, alkali feldspar (perthitic with granophyric intergrowths of quartz and minor plagioclase), traces of anhedral sphene, fluorite, apatite, zircon and anhedral opaques (e.g. at GR MS000514).  Granite (Pgad): fine to medium, dark grey, equigranular, xenolith rich, with biotite, quartz (partly recrystallised and with triple points), rare fine-grained plagioclase partly altered to sericite and epidote, alkali feldspar (commonly perthitic and minor microcline), secondary dolomitic carbonate, traces of zircon and anhedral sphene; brecciated in places (e.g. at GR LS984552). Possibly intruded by Pgaf at GR LS982551 (relationship not clear).  Granite (Pgaf): medium, even-grained, pink, leucocratic, with biotite partly altered to chlorite, sericite intergrown with chlorite, partly recrystallised quartz with straight grain boundaries and triple points in places, plagioclase partly altered to finely granular epidote and sericite, alkali feldspar (commonly perthitic); brecciated or sheared in places (e.g. GR LS956570). Intrudes Hatches Creek Group at GR LS941582 and possibly Pgad at GR LS982551).  Granodiorite (Pgas): fine to medium, heterogranular, xenolith rich, with quartz (partly recrystallised), rich in biotite with accessory zircons, alkali feldspar (microcline and perthite common), subhedral sericitised plagioclase, and traces of tourmaline and anhedral opaque minerals; typically deeply weathered; protomylonitic in places (e.g. at GR MS556328).|16-MAY-23
24152|Ali Curung Granite|Relationships and boundaries|Intrudes the Hatches Creek Group.|16-MAY-23
24152|Ali Curung Granite|Structure and Metamorphism|Sheared in places.|16-MAY-23
24152|Ali Curung Granite|Age reasons|Younger than the Hatches Creek Group (maximum age Early Proterozoic). May be contemporaneous with the Elkedra Granite, which also intrudes the Hatches Creek Group and has been dated by the Rb-Sr whole rock method at about 1660 Ma (Blake and others, 1987).|16-MAY-23
27281|Alice Springs Granite|Name source|Alice Springs township in Alice Springs 1:100 000 Sheet area.|16-MAY-23
27281|Alice Springs Granite|Type section locality|Typical specimens of the outcrop can be seen around the Alice Springs Telegraph Station.|16-MAY-23
27281|Alice Springs Granite|Extent|Extends from the northern part of the Alice Springs township to the Charles River Fault in Alice Springs 1:100 000 Sheet area.|16-MAY-23
27281|Alice Springs Granite|Lithology|Muscovite-biotite granite. In places the granite contains white microcline laths up to 10 cm long.|16-MAY-23
27281|Alice Springs Granite|Relationships and boundaries|Conformable contact with Sadadeen Range gneiss (new name) and a lens of calc-silicate rock. Dolerite dykes of the Stuart Dyke Swarm intrude the Granite.|16-MAY-23
27281|Alice Springs Granite|Age reasons|Isotopic redistribution at about 1100 m.y. May have been emplaced or undergone thermal metamorphism at this time.|16-MAY-23
27281|Alice Springs Granite|Proposed publication|Geological report on the 1:100 000 scale mapping of southeastern Arunta Block, Alice Springs 1:250 000 Sheet area, Northern Territory, by R.D. Shaw et al. BMR. Microfiche report in prep.|16-MAY-23
27281|Alice Springs Granite|Comments|Reason for proposed name: Homogeneous granitic body surrounded by ortho augen gneiss. Distinctive and quite different from neighbouring rocks.|16-MAY-23
27281|Alice Springs Granite|Defn Reference|80/20787|16-MAY-23
28277|Alinjabon Sandstone|Name source|Alinjabon Rockhole on Bonney Creek, GR 590183, NW Davenport Range 1:100 000 Sheet area, Bonney Well 1:250 000 Sheet area.|16-MAY-23
28277|Alinjabon Sandstone|Type section locality|2 km E of Coulters Waterhole (latitude 20o59'55"S, longitude 135o01'50"E), above type section of Errolola Sandstone; base at GR047780, top at GR052780, Hatches 1:100 000 Sheet area. Consists of basal recessive beds (friable kaolinic arenite exposed) about 50 m thick, overlain by about 100 m of ridge-forming, thin to medium-bedded, fine to medium-grained white quartz arenite, overlain by recessive beds (again, mainly friable arenite exposed) about 200 m thick, overlain by ridge-forming thin bedded fine and medium-grained feldspathic (or lithic) arenite about 100 m thick (top); sequence dips about 80oE.|16-MAY-23
28277|Alinjabon Sandstone|Extent|Crops out throughout Davenport Province (E and central parts Bonney Well, SW part Frew River, NW part Elkedra, NE part Barrow Creek 1:250 000 Sheet areas).|16-MAY-23
28277|Alinjabon Sandstone|Thickness range|Generally about 500 m, but ranges between about 350 m and 750 m.|16-MAY-23
28277|Alinjabon Sandstone|Lithology|Ridge-forming quartz arenite and feldspathic or lithic arenite, interbanded with recessive siltstone, arenite, shale, ferruginous arenite, and locally, mainly at or near base, altered mafic lava.|16-MAY-23
28277|Alinjabon Sandstone|Relationships and boundaries|Conformably overlies Errolola Sandstone; base taken at base of recessive band overlying ridge-forming arenite of Errolola Sandstone. Top taken at contact between ridge-forming fine-grained arenite and overlying recessive beds of Lennee Creek Formation.|16-MAY-23
28277|Alinjabon Sandstone|Age reasons|Younger than 1870 Ma (U-Pb zircon date on volcanics in the Warramunga Group, which is unconformably overlain by the Hatches Creek Group), and older than about 1640 Ma (Rb-Sr whole-rock approximate date on granite which intrudes the Hatches Creek Group).|16-MAY-23
28277|Alinjabon Sandstone|Comments|Part of the Hanlon Subgroup of the Hatches Creek Group. Is a region-wide unit of alternating resistant arenite and generally subordinate recessive arenite or lutite readily distinguished from thick underlying ridge-forming arenite and overlying recessive lutite units.|16-MAY-23
28277|Alinjabon Sandstone|Proposer|Stewart A.J.|16-MAY-23
81826|Alkara Suite|Name source|Alkara Creek (135.75degreesE 22.50degreesS (GDA2020)) in HUCKITTA 1:250 000 mapsheet, Northern Territory.|16-MAY-23
81826|Alkara Suite|Constituents|Jamaica Granite, Canefire Granite.|16-MAY-23
81826|Alkara Suite|Geomorphic expression|Generally exposed as hills, nubbins, and pavement.|16-MAY-23
81826|Alkara Suite|Type section locality|Outcrops with both members of the Alkara Suite are rare; however a type locality around 135.540degreesE 22.749degreesS (GDA2020) has outcrops of both Jamaica and Canefire granites.|16-MAY-23
81826|Alkara Suite|Description at type locality|The type area comprises both Jamaica and Canefire granites in the hinge zone of a folded body of Carmencita Metadolerite. The Canefire Granite at this location is medium-grained, porphyritic quartz-K-feldspar-plagioclase+/-biotite granite-gneiss with up to 2 cm K-feldspar porphyroclasts. The Jamaica Granite at this location is a foliated, garnet-bearing, K-feldspar-plagioclase-quartz granite. Garnet is mm or sub-mm with pseudomorphs of biotite-after-garnet. The contact between these units is generally obscured, but where observed is diffuse.|16-MAY-23
81826|Alkara Suite|Extent|Outcrops in Kanandra Domain of southwestern HUCKITTA (Weisheit et al in prep) and possibly eastern ALCOOTA (Beyer et al 2022) 1:250 000 mapsheets, west of the abandoned Molyhil mine, north of Plenty and Marshall rivers and south of the Mopunga Range (west of ~135.72degreesE and between ~22.6323-22.7678degreesS (GDA2020)).|16-MAY-23
81826|Alkara Suite|General description|The Alkara Suite comprises variably-deformed anatectic S-type granites derived by partial melting of the Kanandra Metamorphics. The Jamaica Granite is garnet-bearing, whereas the Canefire Granite does not have garnet. The two granite units are otherwise difficult to distinguish from one another as they both have a similar appearance, similar K-feldspar?plagioclase?quartz?biotite mineralogy, and similar degree of weathering.|16-MAY-23
81826|Alkara Suite|Lithology|The Canefire Granite is medium-grained, porphyritic quartz-K-feldspar-plagioclase-biotite granite-gneiss with up to 2 cm K-feldspar porphyroclasts. The Jamaica Granite is a foliated, garnet-bearing, K-feldspar-plagioclase-quartz granite. Garnet is mm or sub-mm with pseudomorphs of biotite-after-garnet.|16-MAY-23
81826|Alkara Suite|Depositional environment|Genesis: Formed via melting of thickened metasedimentary crust during granulite-facies metamorphism in a Palaeoproterozoic tectonothermal cycle. The Jamaica Granite contains abundant garnet, supporting derivation from an aluminous metasedimentary parent rock. The Canefire Granite, although lacking garnet, is also classified as an S-type but derived from a less fertile rock type.|16-MAY-23
81826|Alkara Suite|Relationships and boundaries|The constituent units contain xenoliths of, and intrude Kanandra Metamorphics and Carmencita Metadolerite.|16-MAY-23
81826|Alkara Suite|Identifying features|The Alkara Suite comprises anatectic S-type granites derived via partial melting of the Kanandra Metamorphics. Compositions of the Alkara Suite are uniformly felsic; its constituent units are inferred to be cogenetic and coeval based on mineralogical, compositional, and structural similarities.|16-MAY-23
81826|Alkara Suite|Structure and Metamorphism|Weakly gneissic to undeformed distal to shear zones; strongly gneissic to mylonitic within shear zones. Anatectic granites; locally retrogressed to greenschist facies in shear zones.|16-MAY-23
81826|Alkara Suite|Age reasons|SHRIMP 207Pb/206Pb age of 1735 +/- 4 Ma for zircon from a sample of the Canefire Granite (Kositcin et al 2020), and LA?ICP?MS 207Pb/206Pb age of 1724 +/- 6 Ma for Jamaica Granite (Beyer et al 2022).|16-MAY-23
81826|Alkara Suite|Alteration and Mineralisation|Locally deeply weathered, bleached, silicified, sericitised. No known associated mineralisation.|16-MAY-23
81826|Alkara Suite|Geophysical Expression|Magnetic high trends, and irregular patchy magnetic high responses.|16-MAY-23
81826|Alkara Suite|Geochemistry|S-type monzogranite and minor syenogranite generally with shoshonite and minor high-K series composition. Peraluminous composition. Negative correlations between silica and most of the major element oxides, excluding K2O and Na2O. Pronounced negative Eu anomalies and HREE depletion.|16-MAY-23
81826|Alkara Suite|Defn author|Barry Reno, Anett Weisheit, Eloise Beyer, Pablo Farias (NT Department of Industry, Tourism and Trade, Northern Territory Geological Survey) 3-MAY-2022.|16-MAY-23
81826|Alkara Suite|References|Beyer E et al, in prep. Alcoota, Northern Territory (Second Edition). 1:250 000 geological map series explanatory notes, SF53-11. Northern Territory Geological Survey, Darwin.  **Beyer EE and Whelan JA, 2021. Revising the igneous stratigraphy in the eastern Aileron Province: implications for geodynamic setting between ca 1.81-1.71 Ga. Annual Geoscience Exploration Seminar (AGES) Proceedings, Alice Springs, Northern Territory, 20?21 April 2021. Northern Territory Geological Survey, Darwin.  **Beyer EE, Whelan JA, Reno BL, Weisheit A, Thompson J, Meffre S, Huang H, and Woodhead JD, 2022. Summary of results. NTGS laser ablation ICP-MS U-Pb-Hf geochronology project: selected samples from HUCKITTA 1:250 000 mapsheet, May 2011-October 2018. Northern Territory Geological Survey, Darwin.  **Kositcin N and Reno BL, 2020. Summary of results. Joint NTGS-GA geochronology project: Aileron and Irindina provinces, Jinka and Dneiper 1:100 000 mapsheets, 2019. Northern Territory Geological Survey, Record 2020-001.  **Reno BL, Weisheit A, Beyer EE and PG Farias 2022. Jinka, Northern Territory. 1:100 000 geological map series explanatory notes, 6052. Northern Territory Geological Survey, Darwin.  **Weisheit A et al, in prep. Huckitta, Northern Territory (Third Edition). 1:250 000 geological map series explanatory notes, SF53-11. Northern Territory Geological Survey, Darwin.|16-MAY-23
41842|Alkipi Metamorphics|Name source|Alkipi (Mount Larrie) outstation 23o 16' 00" S, 131o 49' 00" E, MOUNT LIEBIG|16-MAY-23
41842|Alkipi Metamorphics|Unit history|Previously included within undifferentiated gneiss, schist, amphibolite, quartzite, granite, dolerite and pegmatite of the Arunta Complex  (Ranford 1969)|16-MAY-23
41842|Alkipi Metamorphics|Geomorphic expression|Low to moderate rubbly hills|16-MAY-23
41842|Alkipi Metamorphics|Type section locality|1 km north of  Mount Larrie copper prospect. at 23? 16' 41.76" S, 131? 48' 41.87" E (WGS 84), MOUNT LIEBIG.|16-MAY-23
41842|Alkipi Metamorphics|Description at type locality|Garnet-biotite-sillimanite metapelite, interlayered with metaspsammite. The pelite has a strong non-coaxial strain fabric defined by biotite and sillimanite that wraps porphyroclasts of garnet, K-feldspar and quartz. The porphyroclasts belong to an earlier high-grade migmatitic mineral assemblage.|16-MAY-23
41842|Alkipi Metamorphics|Extent|In hills across northern half of MOUNT LIEBIG, north of Belt Range and Amunurunga Range|16-MAY-23
41842|Alkipi Metamorphics|Lithology|Garnet-biotite-sillimanite metapelite, metapsammite, quartzose metasediment; less abundant quartzite, strained biotite granite, felsic migmatite; minor mafic granulite and amphibolite|16-MAY-23
41842|Alkipi Metamorphics|Relationships and boundaries|Intruded by the Ulambaura Granodiorite, Belt Granite and Papunya Igneous Complex. Unconformably overlain by Heavitree Quartzite. The contact with Glen Helen Metamorphics (Warren and Shaw 1995) is a thrust fault.|16-MAY-23
41842|Alkipi Metamorphics|Age reasons|late Palaeoproterozoic. Two samples of metapelite have maximum deposition ages of 1670-1650 Ma, based on SHRIMP U-Pb dating of detrital zircons, with metamorphic zircon rims with ages of ~1640 Ma (Kinny 2002).|16-MAY-23
41842|Alkipi Metamorphics|Correlations|No known direct correlatives, but metasediments within the unit are a similar age to cordierite granulites in the Yaya Metamorphic Complex at 23o 15' 27.43" S, 131o 33' 13.93" E (Kinny 2002)|16-MAY-23
41842|Alkipi Metamorphics|Comments|Interpreted to be a package of siltstones and sandstones, intruded by granites and mafic rock, that was metamorphosed to granulite facies during the 1640-1635 Ma Liebig Orogeny, and reworked at upper amphibolite facies during the 1590-1560 Ma Chewings Orogeny. Due to the degree of deformation and metamorphism and heterogeneity of rocktypes, it is possible that this unit may include rocks of significantly different ages. It can be distinguished from the rest of the Yaya Metamorphic Complex by the absence of calc-silicate rock, and relative lack of mafic granulite or massive cordierite granulite.|16-MAY-23
41842|Alkipi Metamorphics|References|Kinny PD, 2002. SHRIMP U-Pb geochronology of Arunta Province samples from the Mount Liebig and Lake Mackay 1:250 000 mapsheets. Northern Territory Geological Survey, Technical note 2002-015. **Ranford LC, 1969. Mount Liebig, Northern Territory (First Edition). 1:250 000 geological map series explanatory notes, SF52-16. Bureau of Mineral Resources, Australia. **Scrimgeour IR, Close DF & Edgoose CJ, in prep. Mount Liebig, Northern Territory (Second Edition) 1:250 000 geological map series explanatory notes, SE 52-16. Northern Territory Geological Survey, Darwin. **Warren RG and Shaw RD 1995. Hermannsburg, Northern Territory (Second Edition). 1:250 000 geological map series explanatory notes, SF-53-13. Northern Territory Geological Survey, Darwin.|16-MAY-23
26291|Aloolya Gneiss|Name source|Aloolya Bore, 11km E of main outcrop body of Aloolya Gneiss, Tea Tree 1:100 000 Sheet. Metric grid reference: 318300E, 7530400N.|16-MAY-23
26291|Aloolya Gneiss|Type section locality|3.3 km SW of Bluebush Bore. Metricgrid ref. of T.L. = 299200E, 7535300N. Tea Tree 1:100 000 (5553). A large clean nearly vertical rock face shows Aloolya Gneiss intruding Anmatjira Orthogneiss.|16-MAY-23
26291|Aloolya Gneiss|Extent|Two separate bodies on N. flank of SE part of Anmatjira Range, Tea Tree 1:100 000 Sheet area. Larger body is elongated NW/SE, measures 8 km by 2 km is located at extreme SE end of Anmatjira Range. Smaller body is about 3 km across, and is located about 5 km NW of the larger body, and 3 km SW of Bluebush Bore. The bodies are separated by older Anmatjira Orthogneiss, and are regarded as parts of one intrusion.|16-MAY-23
26291|Aloolya Gneiss|Lithology|Leucocratic evenly medium-grained pale gneissic granite; normal granitic minerals, plus clots of tourmaline and garnet.|16-MAY-23
26291|Aloolya Gneiss|Relationships and boundaries|Intrudes the Tyson Creek granulite (q.v.), intrudes the Anmatjira Orthogneiss thermally metamorphoses Possum Creek Charnockite (q.v.). Probably intrudes Weldon metamorphics (q.v.) (adjoins, but no actual relationship seen). Is intruded by dykes of aplite, pegmatite, metamorphosed basic rock, and by quartz veins.|16-MAY-23
26291|Aloolya Gneiss|Age reasons|Only slightly younger than Anmatjira Orthogneiss, which is dated at 1642 +/- 100 m.y. by Rb-Sr on whole rocks (L.P. Black, BMR pers. Comm., 1975). Early Carpentarian.|16-MAY-23
26291|Aloolya Gneiss|Proposed publication|2. 'Geology of the Northwestern Part of the Arunta Block, N.T.' - BMR Publication.|16-MAY-23
26291|Aloolya Gneiss|Comments|Reason for Proposed Name: a distinctively textured and mappable granite gneiss body.|16-MAY-23
81848|Alroy Formation|Name source|Alroy Formation is named after the ALROY 1:250k mapsheet, SE53-15.|16-MAY-23
81848|Alroy Formation|Unit history|Alroy Formation as defined here includes 'migmatitic paragneiss' and 'felsic volcaniclastic' of Cross et al., (2020).|16-MAY-23
81848|Alroy Formation|Geomorphic expression|No known outcrops.|16-MAY-23
81848|Alroy Formation|Type section locality|Drillhole NDIBK02, down-hole depth from 165.22 m to 347.04 m (EOH). Drillhole location 606036mE 7839142mN (MGA94 zone 53K)/ 19.539694S 136.010731E. Drill core is stored at the NTGS core library in Alice Springs.|16-MAY-23
81848|Alroy Formation|Description at type locality|Dark green-grey pelitic and psammitic schist and phyllite. Prominent banding in areas reflects primary lithological boundaries (i.e. bedding). More pelitic beds contain abundant metamorphic muscovite and biotite, as well as occasional cordierite grains.|16-MAY-23
81848|Alroy Formation|Extent|Widespread throughout the ALROY and FREW RIVER mapsheets and might extend beyond these mapsheets. The only area in ALROY where the Alroy Formation is known to be absent is in drillhole NDIBK04; this most likely represents post-depositional erosion. It is likely that the Alroy Formation was deposited within a widespread basin throughout the East Tennant region.|16-MAY-23
81848|Alroy Formation|General description|The Alroy Formation is defined as a variably metamorphosed sedimentary succession, with a minor volcanic component. The precursor sedimentary rocks were deposited in East Tennant between ca. 1870 Ma and 1855 Ma, immediately prior to the onset of regional tectono-magmatism and metamorphism. This classification is based on consistent detrital zircon age data from nine samples throughout ALROY (Kositcin et al., in prep; Cross et al. 2020). These data suggest that, where analysed, units included within the Alroy Formation shared a source region and were deposited at the same time across much of the East Tennant region. The spatial distribution of constituent lithologies of the Alroy Formation are unclear based on the available sparse drillhole data. Lithologies of the Alroy Formation intersected in drill core are described in the comments section below.|16-MAY-23
81848|Alroy Formation|Thickness range|182 m (incomplete) in type section. Alroy Formation is highly deformed and the bottom of the unit is not intersected. The Alroy Formation is intersected across 231.6 metres in drillhole NDIBK08, 167.2 metres in NDIBK01, 181.8 metres in NDIBK02, 175.3 metres in NDIBK03, 146.09 metres in NDIBK06, and 23.2 metres in NDIBK10. Other drillholes intersect the Alroy Formation over about 100?200 metres. No drillholes intersect the base of the Alroy Formation.|16-MAY-23
81848|Alroy Formation|Lithology|Dark green-grey pelitic and psammitic schist and phyllite. More pelitic beds contain abundant metamorphic muscovite and biotite, as well as occasional cordierite grains.|16-MAY-23
81848|Alroy Formation|Depositional environment|Precursor sediment of the Alroy Formation may be turbiditic, suggesting subaqueous deposition on a slope. Clark et al. (2022) reported peak metamorphic conditions experienced by parts of the Alroy Formation to be 2.8-3.3 kbar and 655-680 degreesC, with an elevated geotherm being the result of widespread magmatism in the East Tennant area.|16-MAY-23
81848|Alroy Formation|Relationships and boundaries|A sharp nonconformity separates Alroy Formation from the overlying Kalkarindji Suite. Also unconformably overlain by Roadhouse Formation. The bottom of the Alroy Formation is not exposed.|16-MAY-23
81848|Alroy Formation|Identifying features|The Alroy Formation is defined to encompass folded and metamorphosed sedimentary rocks in the vicinity of the ALROY and FREW RIVER 1:250 000 mapsheets. These rocks are predominantly comprised of well-bedded siltstone and mudstone metamorphosed to upper greenschist- and lower amphibolite-facies conditions, although graphitic and dolomitic intervals are present locally (e.g. in drillholes DDH003, NDIBK08 and DD80AL3).  Other characteristic features of the Alroy Formation are its ca. 1870-1855 Ma age (largely defined by cross-cutting intrusive igneous rocks and detrital zircon maximum depositional ages) and distinctive detrital zircon age spectrum, which is characterised by a dominant population at ca. 1860?1870 Ma, with a scattering of Paleoproterozoic and Archean ages.|16-MAY-23
81848|Alroy Formation|Structure and Metamorphism|The Alroy Formation has been variably deformed and metamorphosed. Metamorphic grade appears to be associated with a northeast-southwest-trending corridor at East Tennant, bounded to the north and south by the Gulunguru and Lamb faults, respectively. Within this corridor, the Alroy Formation has been isoclinally folded and sheared, and has been metamorphosed to upper-greenschist- to amphibolite-facies conditions. In some locations, lower-grade retrograde assemblages overprint peak metamorphic assemblages. Amphibolite-facies porphyroclasts commonly both overprint and are wrapped by the main shear fabric, suggesting that deformation and medium-grade metamorphism were coeval. In some cases, metamorphic assemblages lack signs of intense tectonism. Many samples of the Alroy Formation contain several generations of tectonic foliations. These generally trend northeast?southwest. Intrusive rocks, almost all of which were emplaced at ca. 1850 Ma, are far less deformed than metasedimentary rocks in the East Tennant area. However, this may simply reflect rheology during deformation. Cross-cutting relationships are difficult to determine in drill core, although in many cases, less-deformed intrusive rocks are still wrapped by the main tectonic foliation. Overall, it seems that some deformation predated intrusive activity, but that ductile tectonism continued after intrusive emplacement (Clark et al., 2022).  Two drill core intersections, which are only tentatively included within the Alroy Formation, were obtained outside of the central corridor and exhibit only sub-greenschist facies metamorphic assemblages. The southeast intersection (drill core DDH003) is not oriented. However, the northwest intersection contains a steeply dipping, folded turbiditic sequence. Well-developed axial-planar cleavage in this sequence parallels foliation within the central, higher-grade corridor. Therefore, the central corridor likely represents a discrete ca. 1850 Ma tectono-metamorphic feature. Brittle reactivation of older ductile structures at East Tennant, most prominently the Gulunguru and Lamb faults, has resulted in the exposure of different crustal levels, which further accentuates the exposure of higher-grade rocks of the Alroy Formation within the central corridor.|16-MAY-23
81848|Alroy Formation|Age reasons|The age of the Alroy Formation is bracketed between numerous SHRIMP U-Pb detrital zircon maximum deposition ages of about 1870 Ma, and cross-cutting intrusive rocks of the ca. 1855 Ma Mount Lamb Suite (Kositcin et al., in prep). Specific units of the Mount Lamb Suite that have been observed to intrude the Alroy Formation in drill core include the Duckling Granodiorite, Francis Dam Granodiorite, and Joey Granite.|16-MAY-23
81848|Alroy Formation|Correlations|The Alroy Formation has been demonstrated to be widespread throughout the East Tennant region (Kositcin, Cross et al., in prep). In the neighbouring Tennant Region and Murphy Province, coeval marine sequences of the Warramunga Formation (and correlative Junalki Formation and Woodenjerrie beds) and Murphy Metamorphics are equally widespread. It is thus possible that all three successions formed part of a single basin and are, in part, correlatives. However, this is yet to be robustly demonstrated.|16-MAY-23
81848|Alroy Formation|Alteration and Mineralisation|Minor hematite and magnetite alteration, in association with minor sulfide (pyrite, trace chalcopyrite) alteration, is present in drillhole DDH005 (Collings, 2009).|16-MAY-23
81848|Alroy Formation|Geophysical Expression|The Alroy Formation is lithologically complex. Therefore, its geophysical expression is highly variable. It is generally denser than felsic intrusive rocks and overlying stratigraphy, and can be distinguished on this basis in gravity data. Elevated magnetic susceptibilities in some parts of the Alroy Formation can be seen in regional geophysical imagery. These features can be identified as belonging to the Alroy Formation as they match the regional structural trend, a significant component of which reflects ca. 1850 Ma deformation in the Alroy Formation. However, care must be taken, as the magnetically susceptible Kalkarindji Suite also often follows this trend, either as a result of flows following palaeotopography, or of younger faulting and alteration.|16-MAY-23
81848|Alroy Formation|Defn author|A.D. Clark 24-MAR-2022|16-MAY-23
81848|Alroy Formation|Proposed publication|Schofield and Clark et al., (in prep). Geology of the East Tennant area, Northern Territory, journal publication.|16-MAY-23
81848|Alroy Formation|Comments|3. DD79AL2/DD80AL3, 190 to 310 m/183.50 to 346.20 m, both holes drilled at approx. 135.537?E 19.698?S: Twin boreholes intersecting a sequence of foliated marble, quartz-muscovite-graphite-andalusite schist, chert, and garnet-biotite-amphibole-magnetite schist. Pyrite is locally abundant, occurring in more carbonaceous lithologies within bedding planes and along the main tectonic foliation. Magnetite-rich bands occur throughout the drill core, and appear to correspond with primary bedding horizons. Overall, the basement rocks in these drill cores appears to be a metamorphosed sequence of psammite, shale, banded iron formation and carbonate. They are lithological comparable to the lower intervals of the Alroy Formation in DDH005. However, there are also similarities between these rocks and the older Confusion Dam Formation or Kerringnew Formation in drillhole NDIBK04. There are no detrital zircon age data available from the DD79AL2/DD80AL3 drill cores. These rocks are tentatively included within the Alroy Formation, in common with almost all other deformed metasedimentary rocks in the East Tennant area. Further analysis is required to confirm this hypothesis.|16-MAY-23
81848|Alroy Formation|Comments|2. NDIBK10, 734.14 to 765.67 m, 593827mE 7813094mN, MGA94, zone 53K: Paragneiss and/or migmatite. Only intersected in the bottom ~30 m of drill core. Quartz-feldspar bands are interfoliated with more biotite-rich bands that commonly contain muscovite and sillimanite. This rock is lithologically similar to the Alroy Formation in NDIBK03 and the upper interval of the Alroy Formation in DDH005, although in NDIBK10 the gneissic banding is more pronounced, less wavy and more consistent in orientation. *DDH003, 164.33 to 270.40 m, 631100mE 7805480mN, MGA94, zone 53K:  Interbedded hematitic siltstone and sandstone unconformably underlying the Kalkarindji Suite. Metamorphosed to sub-greenschist-facies conditions. This interval is lithologically similar to younger stratigraphy in NDIBK07. However, detrital zircon data is indistinguishable from the Alroy Formation (Cross et al. 2020). Similar to NDIBK06, this drill core is located a significant distance, although to the south in this case, from other intersections of the Alroy Formation. Thus, it is only tentatively included within the Alroy Formation. *DDH005, 147.42 to 284.40 m, 600288mE 7841346mN, MGA94 zone 53K: Three distinct lithological intervals from immediately beneath the Kalkarindji Suite until EOH. Upper interval (147.42 m to 202.10 m down-hole depth) comprises quartz-feldspar-biotite-muscovite-andalusite-cordierite-sillimanite gneiss. Banding is defined by more biotite-rich (pelitic) layers vs more quartz-feldspar-rich layers. Biotite mats, muscovite grains, and quartz- and feldspar-rich bands together define a composite tectono-metamorphic fabric. The lower part of this interval becomes progressively affected by low-grade, retrograde alteration and veining characterised by chlorite and fine-grained white mica. This interval is separated from the medial interval by a zone of faulting and brecciation, which appears to be associated with the low-grade alteration.  The medial interval (202.10 m to 253.33 m down-hole depth) contains thinly banded, amphibole-quartz rock, becoming more carbonaceous and pelitic towards the bottom of the interval. Rare zones preserve sheared layers of quartz as well as amphibole- and biotite-rich rock. However, much of the interval exhibits signs of intense hydrothermal alteration. An early assemblage of pyrite and magnetite, which overprints the shear foliation, has been almost entirely overprinted by an assemblage comprising hematite, white mica, chlorite and pyrite. This latter assemblage is associated with quartz-carbonate veins which locally contain minor chalcopyrite.The lower interval [253.33 to 284.40 m (EOH)] consists of grey-green dolomitic marble with zones of pyrrhotite, pyrite and magnetite. It is highly deformed and metamorphosed, and its relationship with the medial interval is difficult to determine. It is worth noting that the upper interval is the only part of the Alroy Formation in this drill core that has been sampled for detrital zircon age dating as of 24/3/2022 (Cross et al. 2020). The two lower intervals are tentatively included within the Alroy Formation here due to relative similarities in metamorphic grade and spatial proximity. However, it is possible that these lower intervals might be better included within the older Confusion Dam Formation or Kerringnew Formation intersected in NDIBK04, as they are, in part, lithologically comparable to these units.|16-MAY-23
81848|Alroy Formation|Comments|1. Variations in the lithology of the Alroy Formation are outlined below by briefly describing the formation in individual drillholes. Note that some of the intervals in NDIBK drillholes contain lesser amounts of intrusive rocks that postdate the Alroy Formation. *NDIBK01, 184.65 to 351.80 m, 627699mE 7862236mN, MGA94, zone 53K: Dark green-grey, banded cordierite-sillimanite schist. Relict detrital clasts of quartz and feldspar in some locations. Primary sedimentary fabric of pelitic sedimentary protolith (likely an aluminium-rich, well-bedded sequence of sandstone and mudstone, with some coarser-grained intervals) is largely obliterated by metamorphism. Abundant metamorphic cordierite growth in some bands has led to grain size inversion, with originally fine-grained pelitic beds now coarser grained and resembling a porphyritic volcanic rock in appearance. Locally strongly sheared, with mica grains and recrystallised quartz ribbons defining a strong shear fabric. *NDIBK02, 165.22 to 347.04 m, 606036mE 7839142mN, MGA94, zone 53K: Dark green-grey pelitic and psammitic schist and phyllite. Prominent banding in areas reflects primary lithological boundaries (i.e. bedding). More pelitic beds contain abundant muscovite and biotite, as well as occasional cordierite grains. Probably represents a less-metamorphosed version of rocks intersected in NDIBK01. *NDIBK03, 175.45 to 350.70 m, 599262mE 7837276mN, MGA94, zone 53K: Dark to light grey gneiss. A supracrustal protolith is likely given the abundance of mica and common presence of sillimanite and relict cordierite. Banding is contorted, discontinuous and locally overprinted by diffuse zones of quartz-feldspar rock. This could be interpreted to indicate in-situ partial melting of the host rock. Overall, the interval of the Alroy Formation in this drill core is similar to the upper interval of the Alroy Formation in DDH005, which is located only four kilometres to the north.  *NDIBK06, 358.61 to 504.70 m, 603011mE 7880694mN, MGA94, zone 53K: Dark grey-green and maroon interbedded slate, siltstone and sandstone. Local volcanoclastic intervals may be present. Prominent normal grading is present in repetitive sequences of coarser and finer material throughout most of the drill core. In thin section, subrounded grains of quartz, feldspar and minor mica are suspended within a fine-grained matrix of detritus. These observations suggest that these rocks were deposited as a sequence of turbidity flows. A slaty cleavage is locally well-developed at an oblique angle to bedding. This is one of the least deformed and metamorphosed intervals of the Alroy Formation. It was obtained far to the north of all other drill cores in the East Tennant region, and across a significant structural/metamorphic boundary. Therefore, these rocks are only tentatively included within the Alroy Formation. As the detrital zircon spectra and maximum deposition age are comparable to other samples of the Alroy Formation, it is plausible that the drill core in NDIBK06 represents the original protolith of other pelitic intervals of the Alroy Formation which have since been metamorphosed to amphibolite-facies conditions.  *NDIBK08, 116.00 to 347.62 m, 627699mE 7862236mN, MGA94, zone 53K: Finely banded phyllite and calc-silicate with more massive marble intervals. Minor pegmatites intrude these rocks and are associated with pyrite and magnetite mineralisation. There are no detrital zircon data available from this drill core. However, as these rocks are lithologically similar to the middle and lower intervals tentatively included in the Alroy Formation in DDH005, which is located 30 km along strike to the southwest, they are also tentatively included in the Alroy Formation.|16-MAY-23
81848|Alroy Formation|References|pre-definition refs: Peter S Collin[g]s, 2013: Annual and Final Report for EL 23726 -801- Project, Jacaranda Alliance JV, Barkly Highway, NT  **A. A. Snelling, 1980: Final exploration report for EL 2043, C.R.A. Exploration PTY LTD, Dalmore, NT  **Donnellan N and Johnstone A, 2004. Mapped and Interpreted Geology of the Tennant Region 1:500 000 scale. Northern Territory Geological Survey, Darwin and Alice Springs.  **A. J. Stewart, 2018: Solid Geology of the Tennant Creek - Mt Isa area, 1:2 500 000 scale, 1st edition [Digital Dataset]. Geoscience Australia, Commonwealth of Australia  **Smith, K.G., 1972, Stratigraphy of the Georgina Basin., Bureau of Mineral Resources, Australia. Bulletin, 111.|16-MAY-23
81848|Alroy Formation|References|Kositcin, N., Cross A.J., et al., in prep. Geochronology of the East Tennant area, Geoscience Australia Record.  **Collings, P.S., 2009. Relinquishment report for EL 23726, for the period 1 August 2003 to 31 July 2009, 801 Project. Open File Company Report, CR2009-0749. https://geoscience.nt.gov.au/gemis/ntgsjspui/handle/1/75417  **Cross, A.J., Clark, A.D., Schofield, A., Kositcin, N., 2020. New SHRIMP U-Pb zircon and monazite geochronology of the East Tennant region: a possible undercover extension of the Warramunga Province, Tennant Creek. In: Czarnota, K., Roach, I., Abbott, S., Haynes, M., Kositcin, N., Ray, A., Slatter, E. (Eds.), Exploring for the Future: Extended Abstracts, Geoscience Australia, Canberra, 1?4. http://dx.doi.org/10.11636/132771  **Clark, A.D., Morrissey, L., Doubler, M., Kositcin, N., Schofield, A., Skirrow, R., 2022. A newly recognised 1860?1840 Ma tectono-magmatic domain in the North Australia Craton: insights from the Tennant Region, East Tennant area, and the Murphy Inlier, Precambrian Research.|16-MAY-23
21122|Alyangula Subgroup|Name source|Alyangula community, Groote Eylandt (GR PE 530675), in BLUE MUD BAY.|16-MAY-23
21122|Alyangula Subgroup|Unit history|Formerly mapped as part of the now abandoned 'Groote Eylandt beds' (Plumb and Roberts, 1965, 1992).|16-MAY-23
21122|Alyangula Subgroup|Constituents|In ascending order Alyinga Sandstone, Bartalumba Basalt and Dalumbu Sandstone on and around Groote Eylandt. The Woodah Sandstone on other islands and on the mainland is also included in the subgroup and is probably a lateral equivalent of the Alyinga Sandstone.|16-MAY-23
21122|Alyangula Subgroup|Type section locality|As for each component formation.|16-MAY-23
21122|Alyangula Subgroup|Extent|Groote Eylandt and closely associated islands of the Blue Mud Bay (BLUE MUD BAY, PORT LANGDON, CAPE BEATRICE and ROPER RIVER). Minor exposure of Woodah Sandstone on nearby mainland coastal area.|16-MAY-23
21122|Alyangula Subgroup|Thickness range|Maximum thickness is developed on Groote Eylandt, where the estimated composite thickness is 1100m.|16-MAY-23
21122|Alyangula Subgroup|Lithology|Predominantly sandstone and pebbly sandstone with minor pebble and conglomerate, interbedded with basalt and dolerite (Bartalumba Basalt and thin basaltic unit in Dalumbu Sandstone).|16-MAY-23
21122|Alyangula Subgroup|Relationships and boundaries|The Alyinga Sandstone lies disconformably on the Milyema Formation of the Bustard Subgroup. The Woodah Sandstone lies unconformably on the Grindall Formaiton and its intrusivesm and is locally (Bickerton Island) inferred to overlie the Bustard Subgroup (contact not exposed). There is no good exposed stratigraphic top to the subgroup (the youngest rocks of the Dalumbu Sandstone dip beneath the sea). Cretaceous and Cainozoic rocks and sediments lie unconformably over the subgroup in places.|16-MAY-23
21122|Alyangula Subgroup|Age reasons|Probably Statherian (Palaeoproterozoic). The Bickerton Rhyolite in the underlying Bustard Subgroup has been dated by SHRIMP single-zircon U-Pb techniques at ~1815 Mz (Pietsch et al. 1994).|16-MAY-23
21122|Alyangula Subgroup|Correlations|Possibly correlated with the lower Tawallah Group of the southern McArthur Basin.|16-MAY-23
21123|Alyinga Sandstone|Name source|Aylinga Island (GR PE670817) in PORT LANGDON.|16-MAY-23
21123|Alyinga Sandstone|Unit history|Formerly mapped as part of the now abandoned 'Groote Eylandt beds' (Plumb and Roberts, 1965, 1992).|16-MAY-23
21123|Alyinga Sandstone|Geomorphic expression|Joint-controlled, bare rocky outcrops.|16-MAY-23
21123|Alyinga Sandstone|Type section locality|Lower boundary stratotype: Northern Groote Eylandt (north of Yirrumanja at lat. 13o 41'S, long. 136o 35'E; GR PE715862). Reference localities: Outcrop on a small island at lat. 13o 41' 30"S. long. 136o 31' 45"E (GR PE665857) and the northwestern part of Winchelsea Island thought to include the upper part of the formation (lat. 13o 44'S, long. 136o 29'E; GR PE603807).|16-MAY-23
21123|Alyinga Sandstone|Extent|Outcrops on the northern Groote Eylandt, northern Winchelsea Island, North East Isle and on smaller islands to the immediate north and northeast, PORT LANGDON and BLUE MUD BAY.|16-MAY-23
21123|Alyinga Sandstone|Thickness range|Estimated to be of the order of 300m thick.|16-MAY-23
21123|Alyinga Sandstone|Lithology|Thin basal polymict granule to boulder conglomerate and pebbly and cobbly sandstone; white, medium- to coarse-grained, locally pebbly, quartz-rich sandstone with very large trough cross-beds.|16-MAY-23
21123|Alyinga Sandstone|Depositional environment|High-energy braided fluviatile for most of the formation, changing to marginal marine near the top.|16-MAY-23
21123|Alyinga Sandstone|Relationships and boundaries|Disconformablu overlies the Milyema Formation. Inferred to be overlain by Bartalumba Basalt, although there is a considerable covered interval at this level. Based on aeromagnetic evidence, it is intruded by magnetic (probably mafic) dykes.|16-MAY-23
21123|Alyinga Sandstone|Age reasons|Probably Statherian (Palaeoproterozoic). The Bickerton Rhyolite in the underlying Bustard Subgroup has been dated by SHRIMP single-zircon U-Pb techniques at ~1815Ma (Pietsch et al. 1994).|16-MAY-23
21123|Alyinga Sandstone|Correlations|Possibly correlates with the Yiyintyi Sandstone of the Tawallah Group.|16-MAY-23
83022|Amazon Dolerite|Name source|Amazon Dolerite is named after Amazon Lagoon (GDA94, 53K, 610674mE, 7866502mN), which lies approximately 18 km to the northwest of the type intersection of this unit.|16-MAY-23
83022|Amazon Dolerite|Geomorphic expression|No known outcrops.|16-MAY-23
83022|Amazon Dolerite|Type section locality|Drillhole NDIBK08, down-hole depth from 225.84 m to 227.20 m. Drillhole location 627699mE 7862236mN (MGA94 zone 53K) / 19.329762S 136.215637E. Drill core is stored at the NTGS core library in Alice Springs.|16-MAY-23
83022|Amazon Dolerite|Description at type locality|Fine- to medium-grained fractured mafic rock, intensively altered by a propylitic assemblage of calcite, albite/adularia, epidote, chlorite, biotite, quartz and pyrite, with minor talc, actinolite and hematite. Relict primary minerals comprise feldspar and olivine phenocrysts. Intrudes undated folded and metamorphosed sediments of interpreted Alroy Formation.|16-MAY-23
83022|Amazon Dolerite|Extent|Unknown. The minor volume of this unit, and a lack of distinctive geophysical properties relative to the surrounding rocks, together with complexities due to overlying magnetic rocks of the Kalkarindji Suite, result in a unit that is extremely difficult to map undercover.|16-MAY-23
83022|Amazon Dolerite|General description|This unit is only known from drillhole NDIBK08. In addition to the type intersection, the unit is intersected sporadically between 224 m and 231 m down-hole depth. The boundaries between these sporadic intervals of the Amazon Dolerite and the surrounding Alroy Formation are generally sharp and undulatory, with the dolerite cross-cutting sedimentary layering and foliation in the Alroy Formation.|16-MAY-23
83022|Amazon Dolerite|Thickness range|Approximately 1.5 m, apparent thickness only.|16-MAY-23
83022|Amazon Dolerite|Lithology|Altered dolerite.|16-MAY-23
83022|Amazon Dolerite|Depositional environment|Genesis: Limited geochemical data suggests a within-plate environment.|16-MAY-23
83022|Amazon Dolerite|Relationships and boundaries|Both the upper and lower boundary of the Amazon Dolerite constitute intrusive contacts with the Alroy Formation. Contacts are sharp and exhibit signs of violent magma injection and brecciation of Alroy Formation wallrock.|16-MAY-23
83022|Amazon Dolerite|Identifying features|Massive texture, dark colour, relatively young age (see below) and intrusive contacts with surrounding supracrustal rocks of the Alroy Formation.|16-MAY-23
83022|Amazon Dolerite|Structure and Metamorphism|In thin-sections of the limited drill core available, this unit appears largely undeformed and unmetamorphosed. However, the unit exhibits evidence of significant metasomatism (see above).|16-MAY-23
83022|Amazon Dolerite|Age reasons|SHRIMP U?Pb analysis of a sample taken from the type intersection of this unit indicates that it was emplaced at 1596 +/-5 Ma (Kositcin, Cross et al., in prep).|16-MAY-23
83022|Amazon Dolerite|Correlations|None known.|16-MAY-23
83022|Amazon Dolerite|Alteration and Mineralisation|Altered by a propylitic assemblage of calcite, albite/adularia, epidote, chlorite, biotite, quartz and pyrite, with minor talc, actinolite and hematite.|16-MAY-23
83022|Amazon Dolerite|Geophysical Expression|Poorly defined/unknown.|16-MAY-23
83022|Amazon Dolerite|Geochemistry|Two samples of the Amazon Dolerite have been analysed. SiO2 is restricted to 46.5?49.3 wt.%. Relative to the Beef Hole Gabbro, the Amazon Dolerite shows much higher concentrations of high field strength and rare earth elements at equivalent SiO2 concentrations and has affinities with alkali basalt. A single whole rock Nd isotope analysis is very weakly evolved (epsilonNd 1590 Ma = -0.93).|16-MAY-23
83022|Amazon Dolerite|Defn author|A. D. Clark 24-MAR-2022|16-MAY-23
83022|Amazon Dolerite|Proposed publication|Schofield and Clark et al., (in prep). Geology of the East Tennant area, Northern Territory, journal publication.|16-MAY-23
83022|Amazon Dolerite|References|Kositcin, N., Cross A.J., et al., in prep. Geochronology of the East Tennant area, Geoscience Australia Record.|16-MAY-23
24156|Amesbury Quartzite|Name source|Amesbury Bore on Mount Peake 1:250 000 Sheet (AMG GR LR1894).|16-MAY-23
24156|Amesbury Quartzite|Unit history|Originally Amesbury Quartzite Member of the Central Mount Stuart Formation (Offe, 1978; Stewart et al., 1980). Mapped as Central Mount Stuart beds by Smith and Milligan (1964).|16-MAY-23
24156|Amesbury Quartzite|Geomorphic expression|Typically forms cuestas and low rounded ridges.|16-MAY-23
24156|Amesbury Quartzite|Type section locality|16 km east-northeast of Amesbury Bore on Mount Peake 1:250 000 Sheet (AMG GR LR3399; latitude 21o42'30"S, longitude 133o23'15"E), as nominated by Offe (1978).|16-MAY-23
24156|Amesbury Quartzite|Extent|Restricted to scattered outcrops near the central eastern edge of Mount Peake and central western edge of Barrow Creek 1:250 000 sheets.|16-MAY-23
24156|Amesbury Quartzite|Thickness range|20 m at type section (Offe, 1978).|16-MAY-23
24156|Amesbury Quartzite|Lithology|White ripple-marked and cross-bedded orthoquartzite and quartz arenite. Thin basal conglomerate locally present. Characteristic bimodal beds composed of well-rounded and well-sorted quartz granules or small pebbles in a medium-grained arenaceous matrix, occur near base. Desiccation cracks present and clay galls common.|16-MAY-23
24156|Amesbury Quartzite|Relationships and boundaries|Unconformably overlies early Proterozoic crystalline basement. Unconformably overlain locally by Boko Formation (at AMG GR LS5218) or Central Mount Stuart Formation.|16-MAY-23
24156|Amesbury Quartzite|Structure and Metamorphism|Generally low dips rarely exceeding 20o.|16-MAY-23
24156|Amesbury Quartzite|Age reasons|Late Proterozoic or older.|16-MAY-23
24156|Amesbury Quartzite|Correlations|May correlate with Vaughan Springs Quartzite of Ngalia Basin.|16-MAY-23
35317|Amputjuta Dacite|Name source|Amputjuta Outstation, southwestern Hull 1:100 000 mapsheet.|16-MAY-23
35317|Amputjuta Dacite|Unit history|Previously described as unnamed Precambrian porphyroblastic schist, quartz-feldspar porphyry (Forman 1966). Previous 'informal' name- Manananna Porphyry (Forman, 1966)|16-MAY-23
35317|Amputjuta Dacite|Geomorphic expression|Low rounded hills|16-MAY-23
35317|Amputjuta Dacite|Type section locality|4.5 km southwest of Amputjuta Outstation at location 24deg 56' 53.04" S, 129deg 05' 10.25" E (WGS 84).|16-MAY-23
35317|Amputjuta Dacite|Extent|Arcuate belt around the margin of Learmouth Park, southwestern region of Hull 1:100 000 mapsheet.|16-MAY-23
35317|Amputjuta Dacite|Thickness range|n/a|16-MAY-23
35317|Amputjuta Dacite|Lithology|Porphyritic hypabyssal dacite with fine grained phenocrysts of feldspar, less abundant equigranular leucogranite.|16-MAY-23
35317|Amputjuta Dacite|Depositional environment|Shallow level intrusive.|16-MAY-23
35317|Amputjuta Dacite|Relationships and boundaries|Forms part of the 1190-140 Ma Pottoyu Granite Suite (Scrimgeour et al 1999). Intrudes the undivided Pottoyu Granite Suite, overlain by Kulail Sandstone.|16-MAY-23
35317|Amputjuta Dacite|Age reasons|Mesoproterozoic. Pb-Pb evaporation dates on zircon yield an age of 1153 +/- 3 Ma (Close et al, 2002).|16-MAY-23
35317|Amputjuta Dacite|Correlations|Geochemically similar, thus tentatively correlated with the undivided Pottoyu Granite Suite (1190-1140 Ma) and Ilyaralona Granite (1163 +/- 4 Ma).|16-MAY-23
35317|Amputjuta Dacite|Proposed publication|Close, D.F., Edgoose, C.J., Scrimgeour, I.R., 2002. Bloods Range and Hull 1:100 000 geological special, Northern Territory Geological Survey, Explanatory notes.|16-MAY-23
35317|Amputjuta Dacite|Comments|Previous 'informal' name- Manananna Porphyry (Forman, 1966). Ambiguous intrusive relationships with Pottoyu Granite are seen in the field, however geochemical signature is similar suggesting the Amputjuta Dacite is probably a late co-magmatic phase of the Pottoyu Granite- possibly is high level intrusive equivalent.|16-MAY-23
35317|Amputjuta Dacite|References|Close, D.F., Edgoose, C.J., Scrimgeour, I.R., 2002. Bloods Range and Hull 1:100 000 geological special, Northern Territory Geological Survey, Explanatory notes. **Forman, D.J., 1966. Bloods Range Northern Territory 1:250 000 geological series explanatory notes. Sheet (SG53-3). Bureau of Mineral Resources, Australia. **Scrimgeour, I.R., Close, D.F. and Edgoose, C.J., 1999. Petermann Ranges Northern Territory 1:250 000 geological series explanatory notes. Sheet (SG52-7). Northern Territory Geological Survey.|16-MAY-23
80427|Amungee Member|Name source|After Amungee Mungee Station (MGA94 53K 403000mE 8178000mN; Latitude -16.484' longitude 134.093') in southwestern Arnold River 1:100k mapsheet in central-western Tanumbirini 1:250k mapsheet.|16-MAY-23
80427|Amungee Member|Unit history|Equivalent to informal 'Middle' Velkerri Formation of Lanigan et al (1994) and middle Velkerri Formation of subsequent usage. Parent is the Velkerri Formation of the Roper Group.|16-MAY-23
80427|Amungee Member|Constituents|Distinctive, thick, organic-rich mudrock intervals, informally named organofacies A-C in ascending stratigraphic order, are seperated by two relatively organic-lean intervals with relatively higher proportions of interbedded and interlaminated fine sandstone and siltstone. Average thickness of combined A, B and C organofacies is approximately one-third to one-half of total thickness of member, but they can be absent, or comprise up to three quarters of total thickness.|16-MAY-23
80427|Amungee Member|Geomorphic expression|Not differentiated from parent Velkerri Formation in outcrop due to poor exposure. Velkerri Formation is recessive and exposures are generally restricted to rare small outcrops of buff- to white-weathering laminated siltstone and mudstone, or fragments of this lithology in skeletal soil. The formation is present in scarp slopes beneath Moroak Sandstone and also underlies extensive plains.|16-MAY-23
80427|Amungee Member|Type section locality|Amungee Member is not recognised at surface due to poor exposure, and a complete intersection of the member in drillhole, Paciofic Oil and Gas Ltd (POG) Alexander-1 (Barberis and Ledlie 1988) from ca 446m depth (base) to ca 280m (top) is therefore nominated. Velkerri Formation is 555m thick in Alexander-1 (617-62m depth). Alexander-1 is located at MGA94 53K 484523 mE 8322964mN; latitude -15.16911' longitude 134.855921'. Core is housed in the NTGS Core facilities in Darwin.|16-MAY-23
80427|Amungee Member|Extent|Subsurface intersections in drillholes located in Urapunga, Larrimah, Hodgson Downs, Tanumbirini and Bauhinia Downs 1:250k mapsheets, northeastern Northern Territory. Not differentiated from parent formation in outcrop due to poor exposure.|16-MAY-23
80427|Amungee Member|General description|Interlaminated to thinly interbedded, grey-green to dark grey claystone, pale grey siltstone and rare, light grey fine-grained sandstone, with intervals of massive to laminated, grey-green and dark grey to brown-black (carbonaceous) claystone. In comparison to Kalala and Wyworrie members, Amungee Member has a relatively higher proportion of claystone relative to siltstone and sandstone, and a much lower clay content. Informal organofacies A-C are clearly differentiated in hyperspectral data (HyLogger) by a relatively low proportion of quartz accompanied by an increased proportion of secondary sulfates, after pyrite.|16-MAY-23
80427|Amungee Member|Thickness range|166m thick. Complete intersections range from a minimum of 75 m in BHP Minerals Pty Ltd MD4 to a maximum of 502 m in Santos Tanumbirini-1. Other significant intersections include 233 m in BMR Urapunga-4; 276.25 m in POG Altree-2; 460 m in Origin Amungee NW-1; >448 m in Pangaea Birdum Creek-1; 314 m in Origin Kalala S-1; 350.7 m in POG McManus-1; 162 m in POG Scarborough-1; >263.5 m in Falcon Shenandoah-1A; 253.21 m in Pangaea Tarlee-1; 320.22 m in Pangaea Tarlee S-3; and 292.39 m in Pangaea Wyworrie-1.|16-MAY-23
80427|Amungee Member|Lithology|Interlaminated to thinly interbedded, grey-green to dark grey claystone, pale grey siltstone and rare, light grey fine-grained sandstone, with intervals of massive to laminated, grey-green and dark grey to brown-black (carbonaceous) claystone. Three organic-rich claystone-dominated intervals (organofacies A-C in ascending stratigraphic order) are seperated by organic-lean clay-rich intervals with relatively higher proportions of siltstone and sandstone. Organofacies A, B and C are respectively about 30m, 60m and 40m thick in Alexander-1.|16-MAY-23
80427|Amungee Member|Depositional environment|Subtidal, sub-wave base, and generally quiet marine with regular current activity, consistent with periodic turbidity currents (Munson 2016 and references therein).|16-MAY-23
80427|Amungee Member|Relationships and boundaries|Conformable and sharp lower contact with underlying Kalala Member. Conformable upper boundary with overlying Wyworrie Member is gradational over several metres within mudrocks as organic content wanes upward; contact is not clearly defined by lithology and is best picked using a combination of wireline and chemostratigraphic logs.|16-MAY-23
80427|Amungee Member|Identifying features|Amungee Member has a relatively higher proportion of claystone relative to siltstone and sandstone, in comparison to Kalala and Wyworrie members. Occurrence of organofacies A-C is characteristic. See also Geophysical Expression and Geochemistry below.|16-MAY-23
80427|Amungee Member|Structure and Metamorphism|Unmetamorphosed. Flat-lying, or gentle to open folds, and/or brittle faults with minor displacements in most areas. More intense deformation (thrusts, shears, close to tight folds) in vicinity of major fault zones.|16-MAY-23
80427|Amungee Member|Age reasons|Mesoproterozoic. Maximum deposition age constrained by SHRIMP U-Pb zircon ages of 1492 +/- 4 Ma and 1493 +/- 4 Ma from rare tuffs in Showell Member of underlying Mainoru Formation (Jackson et al 1999), and by TIMS U-Pb baddeleyite age of 1312.9 +/- 0.7 Ma age for Derim Derim Dolerite, which intrudes Velkerri Formation (Collins et al 2018). Organic-rich mudrocks from Amungee Member have been dated by Re-Os method at 1417+/- 29 Ma (A organofacies) and 1361 +/- 21 Ma (C organofacies; Creaser and Kendall 2007, Kendall et al 2009).|16-MAY-23
80427|Amungee Member|Correlations|No known correlatives at member level. Parent Velkerri Formation is probably equivalent to Lake Woods beds of Renner Group of Tomkinson Province (Hussey et al 2001), Tijunna Group (in part) of Birrindudu Basin; and Mullera Formation (in part) of South Nicholson Basin (Munson 2016).|16-MAY-23
80427|Amungee Member|Alteration and Mineralisation|Some in situ weathering of labile minerals to clays. Organic-rich intervals have proven source rock potential and are prospective for unconventional petroleum.|16-MAY-23
80427|Amungee Member|Geophysical Expression|A-C shale organofacies are well defined by prominent excursions in gamma and resistivity logs.|16-MAY-23
80427|Amungee Member|Geochemistry|TOC values and carbonate content are appreciably higher throughout Amungee Member than they are in Kalala and Wyworrie members. A-C shale organofacies are well defined by prominent excursions in TOC, phosphate, redox-sensitive trace elements (eg, U, Ni, V, Mo, Zn, Cu, Tl); and by lower log values for some oxides and heavy mineral trace elements (eg, Al2O3, K2O, Sc, Nb, Th, Sn, Cr).|16-MAY-23
80427|Amungee Member|Defn author|TJ Munson, D Revie, April 2018.|16-MAY-23
80427|Amungee Member|Proposed publication|Munson TJ and Revie D, 2018. Stratigraphic subdivision of Velkerri Formation, Roper Group, McArthur Basin, Northern Territory. Northern Territory Geological Survey, Record 2018-006.|16-MAY-23
80427|Amungee Member|Comments|Lower contact with Kalala Member often marked by thin calcite bed (Hoffman 2015). Palynological study of Altree-2 samples did not yield identifiable palynomorphs in Amungee Member (Grey (2015).|16-MAY-23
80427|Amungee Member|References|Barberis C and Ledlie I, 1988. Alexander No 1, EP 4, McArthur Basin, NT. Well completion report. Pacific Oil & Gas Ltd. Northern Territory Geological Survey, Open File Petroleum Report PR1989-0007. **Collins A, Farkas J, Glorie S, Cox G, Blades ML, Yang Bo, Nixon A, Bullen M, Foden JD, Dosseto A, Payne JL, Denyszyn S, Edgoose CJ, Close D, Munson TJ, Menpes S, Spagnuolo S, Gusterhuber J, Sheridan M, Baruch-Jurado E and Close D, 2018. Orogens to oil: government-industry-academia collaboration to better understand the greater McArthur Basin: in Annual Geoscience Exploration Seminar (AGES) Proceedings, Alice Springs, Northern Territory, 20-21 March 2018. Northern Territory Geological Survey, Darwin. 49-51. **Creaser RA and Kendall B, 2007. Re-Os geochronology of organic-rich shales; Placing absolute time pins in ancient sedimentary basins. American Geophysical Union, Fall Meeting 2007, abstract #V31G-01. **Grey K, 2015. Mesoproterozoic biostratigraphic correlation in the Beetaloo Sub-basin, Northern Territory, Australia and potential for correlation with other northern Australian basins: in 'Annual Geoscience Exploration Seminar (AGES) 2015. Record of Abstracts.' Northern Territory Geological Survey, Record 2015-002. **Hoffman TW, 2015. Recent drilling results provide new insights into the western Palaeoproterozoic to Mesoproterozoic McArthur Basin: in 'Annual Geoscience Exploration Seminar (AGES) 2015. Record of Abstracts.' Northern Territory Geological Survey, Record 2015-002, 50-55. **Jackson MJ, Sweet IP, Page RW and Bradshaw BE, 1999. The South Nicholson and Roper Groups: Evidence for the early Mesoproterozoic Roper Superbasin: in Bradshaw BE and Scott DL (editors). 'Integrated basin analysis of the Isa Superbasin using seismic, well-log and geopotential data: an evaluation of the economic potential of the northern Lawn Hill Platform'. Australian Geological Survey Organisation Record 1999/19 (CD ROM), 36-45. **Kendall B, Creaser RA, Gordon GW and Anbar AD, 2009. Re-Os and Mo isotope systematics of black shales from the Middle Proterozoic Velkerri and Wollogorang Formations, McArthur Basin, northern Australia. Geochimica et Cosmochimica Acta 73, 2534-2558. **Lanigan K, Hibbird S, Menpes S and Torkington J, 1994. Petroleum exploration in the Proterozoic Beetaloo Sub basin, Northern Territory. APEA Journal 34, 674-691. **Munson TJ, 2016. Sedimentary characterisation of the Wilton package, greater McArthur Basin, Northern Territory. Northern Territory Geological Survey, Record 2016-003.|16-MAY-23
409|Anamarra Orthogneiss|Name source|Anamarra Creek, 23o06'S, 134o21'E in the Alice Springs 1:250 000 Sheet area.|16-MAY-23
409|Anamarra Orthogneiss|Unit history|Previously mapped as undivided Arunta Complex by Wells et al. (1968).|16-MAY-23
409|Anamarra Orthogneiss|Type section locality|Reference section: Along Anamarra Creek from GR 5751-347431 to 352412.|16-MAY-23
409|Anamarra Orthogneiss|Extent|Unit forms an area of low relief covering about 14 km2 about 5 km north of Mount Johnston.|16-MAY-23
409|Anamarra Orthogneiss|Lithology|Biotite-rich, strongly foliated orthogneiss containing megacrysts of orthoclase; small lenses of mafic granulite and amphibolite within the unit are probably xenoliths. The orthogneiss locally contains hornblende.|16-MAY-23
409|Anamarra Orthogneiss|Relationships and boundaries|Intrudes unnamed unit pCu, which consists mainly of quartzofeldspathic gneiss.|16-MAY-23
409|Anamarra Orthogneiss|Age reasons|Middle Proterozoic; no isotopic data available.|16-MAY-23
410|Anburla Anorthosite|Name source|Anburla Creek.|16-MAY-23
410|Anburla Anorthosite|Unit history|Previously Mount Hay anorthosite (used informally: Glikson, 1984).|16-MAY-23
410|Anburla Anorthosite|Geomorphic expression|Low rises with boulders of fresh rock.|16-MAY-23
410|Anburla Anorthosite|Type section locality|East of Valley Bore, GR 308700 7408500 Anburla 1:100 000 Sheet area.|16-MAY-23
410|Anburla Anorthosite|Extent|Thin layer on north side of Ceilidh Hill, outcrops at the east end of Ceilidh Hill and east of Blackhill Dam.|16-MAY-23
410|Anburla Anorthosite|Thickness range|<1000 m.|16-MAY-23
410|Anburla Anorthosite|Lithology|Plagioclase-rich granofels with hornblende and/or pyroxenes. Metamorphosed to granulite or upper amphibolite facies.|16-MAY-23
410|Anburla Anorthosite|Relationships and boundaries|Spatially associated with Mount Hay Granulite, fault contact with Bunghara Metamorphics.|16-MAY-23
410|Anburla Anorthosite|Structure and Metamorphism|Appears to have been deformed and metamorphosed to granulite or upper amphibolite facies during Strangways Orogeny at about 1750 Ma as part of the Narwietooma Metamorphic Complex.|16-MAY-23
410|Anburla Anorthosite|Age reasons|Middle Proterozoic: affected by the Strangways metamorphism at 1760-1750 Ma.|16-MAY-23
410|Anburla Anorthosite|Defn author|G. Watt, 1992.|16-MAY-23
410|Anburla Anorthosite|Comments|This 'definition' is missing the details of references mentioned in the synonymy, and shows no signs on the card of having been approved.|16-MAY-23
24158|Andagera Formation|Name source|After Andagera bore (AMG reference NS772252) and Andagera Creek (latitude 21o33'S, longitude 135o38'25"E).|16-MAY-23
24158|Andagera Formation|Unit history|Formerly included as the basal conglomerate - sandstone member of the Sandover beds (Smith, Vine and Milligan, 1961; Smith and Milligan, 1966). Outcrops north of Ilbumric bore were originally included in the Tomahawk beds (Smith and Milligan, 1966).|16-MAY-23
24158|Andagera Formation|Type section locality|Holostratotype locality: 17 km north of Ilbumric Bore at latitude 21o17'S and longitude 135o13'40"E (AMG reference NS233463).  Parastratotype locality: 2 km west of Andagera Bore at AMG reference NS750255.|16-MAY-23
24158|Andagera Formation|Extent|Mainly in the northwestern part of Elkedra, also in the southern part of Frew River, the northeastern part of Barrow Creek, and the southeastern part of Bonney Well 1:250 000 sheet areas. The formation is distributed around the margins of the Davenport Ranges, and along some valleys within the ranges.|16-MAY-23
24158|Andagera Formation|Thickness range|Most outcrops are between 5 and 40 m thick; at the holostratotype it is 22 m thick, and 24 m in the parastratotype.|16-MAY-23
24158|Andagera Formation|Lithology|Holostratotype lithology: Massive to thick beds of poorly sorted, well imbricated boulder to cobble conglomerate at the base, fining upward to medium- to thin-bedded, planar and cross-bedded pebble conglomerate and sandstone. Clasts are quartz arenite from the Hatches Creek Group with a minor vein quartz pebble component. Unconformity overlies the Hatches Creek Group; sharply overlain by silicified siltstone of the Arthur Creek Formation (?).  Parastratotype lithology: Medium- to fine-grained sublitharenite, in part feldspathic, partly with an iron-stained matrix; interbedded with laminated red siltstone and lenses of pebble conglomerate at various intervals. Bedding is thin to thick, almost horizontal and ripple-marked on sandstone surfaces in places. Pebbles are of vein quartz and quartz arenite originating from Hatches Creek Group; top eroded. 1.8 km NW of this locality sharply and disconformably overlain by the Arthur Creek Formation.  Lithology: Ranges from intermontane, valley-filled pebble to boulder conglomerate through to alluvial fan pebble to boulder conglomerate grading to pebbly sandstone, sandstone and siltstone. Lateral vertical gradations common between various rock types.|16-MAY-23
24158|Andagera Formation|Relationships and boundaries|Rests unconformably on the Proterozoic Hatches Creek Group and Elkedra Granite. Sharply overlain disconformably by partly silicified siltstone or siltstone rubble of the Arthur Creek Formation.|16-MAY-23
24158|Andagera Formation|Age reasons|Inferred to be Early Cambrian; no fossils found to confirm its age. The overlying Arthur Creek Formation is Late Ordian to Templetonian (Middle Cambrian) in age.|16-MAY-23
24158|Andagera Formation|Correlations|Correlates with the basal unit of the Gum Ridge Formation (Smith, 1964). This basal unit is now named the Andagera Formation (Walley, 1985).|16-MAY-23
24158|Andagera Formation|Name first published by|Wyche T., Blake D.H., Johnson C.R. (86/25489)  Mention Map legend.|16-MAY-23
24158|Andagera Formation|Proposer|Bagas L., Donnellan N., Stidolph P.A.|16-MAY-23
33655|Angatja Granite|Name source|Angatja Outstation, in the immediately adjacent region of South Australia; 26o 4' 5.4"S,130o 18' 27.6"E, MANN.|16-MAY-23
33655|Angatja Granite|Unit history|Comprises part of the Musgrave-Mann Metamorphics of Thomson (1969) and undivided metamorphosed granites of Forman (1972).|16-MAY-23
33655|Angatja Granite|Constituents|Nil defined. Contains some different rock types, as described below, which might be defined as separate units with future work.|16-MAY-23
33655|Angatja Granite|Geomorphic expression|Low rocky hills and outcrops with boulders and tors.|16-MAY-23
33655|Angatja Granite|Type section locality|Porphyritic hornblende granite 25o 58' 27.9"S, 130o 11' 8.8"E.   REFERENCE LOCALITIES: Rapakivi granite 25o 58' 35.2"S, 130o 11' 8.8"E; Charnockite 25o 58' 12.8"S, 130o 8' 55.6"E.|16-MAY-23
33655|Angatja Granite|Extent|On the lower slopes of the eastern Mann Ranges north and east of Mt. Charles (26o 0' 10.7"s, 130o 7' 1.6"E) (MANN) and in low outcrops immediately to the east.  Extent in South Australia is unknown.|16-MAY-23
33655|Angatja Granite|Thickness range|n/a|16-MAY-23
33655|Angatja Granite|Lithology|Foliated porphyritic orthopyroxene-clinopyroxene charnockite, porphyritic hornblende granite, and clinopyroxene-orthopyroxene rapakivi granite. Locally strongly mylonitised, and recrystallised to biotite-clinopyroxene-garnet-hornblende bearing assemblages.|16-MAY-23
33655|Angatja Granite|Depositional environment|n/a|16-MAY-23
33655|Angatja Granite|Relationships and boundaries|Intrudes and contains xenoliths of c.1550 Ma granulite facies felsic gneiss. Intrudes 1078 Ma Alcurra Dyke Swarm, but is intruded by c.1000 Ma mafic dykes and the 800 Ma Amata Dyke Swarm. Rapakivi granite forms dykes 1-5 m wide which intrude granulites.|16-MAY-23
33655|Angatja Granite|Age reasons|Mesoproterozoic. Pb-Pb zircon evaporation age of 1071 +/- 5 Ma for porphyritic hornblende granite at 25o 58' 27.9"S, 130o 11' 8.8"E.|16-MAY-23
33655|Angatja Granite|Correlations|Believed to be related to 1050-1080 Ma granites documented in the western Musgrave Block by Sun et al (1996).|16-MAY-23
33655|Angatja Granite|Proposed publication|Petermann Ranges 1:250 000 geological mapsheet Explanatory Notes|16-MAY-23
33655|Angatja Granite|Comments|Variably mylonitised and metamorphosed at ~12 kbars and 700-750?C during the c.560 Ma Petermann Orogeny.|16-MAY-23
33655|Angatja Granite|References|THOMSON, B.P., 1969.  The Musgrave Block.  In Parkin, L.W. (ed.) Handbook of South Australian Geology. Geological Survey of South Australia, p.39-46.   FORMAN, D.J. (1972). Petermann Ranges, Northern Territory.  1:250 000 geological sheet and explanatory notes.  Bureau of Mineral Resources, Canberra, Australia.   SUN, S-s., Sheraton, J.W., Glikson, A.Y. & Stewart, A.J., 1996.  A major magmatic event during 1050-1080 Ma in central Australia, and an emplacement age for the Giles Complex.  AGSO Research Newsletter, 24, 13-15.|16-MAY-23
39322|Ankala Gneiss|Name source|Ankala Hill (GR 5751-081276), (pronounced "Angkarla"), Laughlen 1:100 000 Sheet area.|16-MAY-23
39322|Ankala Gneiss|Unit history|Previously mapped by Wells and others (1968) as undivided Arunta Complex.|16-MAY-23
39322|Ankala Gneiss|Type section locality|Reference area: Area surrounding Ankala Hill and between there and Gumtree Bore (i.e. between GR 5751-085284 and 5751-042264).|16-MAY-23
39322|Ankala Gneiss|Extent|The unit forms a fault wedge widening eastwards from its apex near Gumtree Bore (GR 5751-42264) to the Pinnacles Fault (GR5751-195308), where it is offset to the south. The unit reappears farther southeast in the Winnecke Goldfield area, and also crops out south of a schist zone (Psr) southeast of the reference area.  It is also considered to occur in the hanging wall sequence at Rankin's Copper Prospect (GR 5751-093242).|16-MAY-23
39322|Ankala Gneiss|Lithology|Quartzofeldspathic gneiss, subordinate calcsilicate gneiss, biotite gneiss, amphibolite and rare marble, meta-ultramafic rock, and quartz-hematite rocks, and extremely rare anthophyllite-rich rock.|16-MAY-23
39322|Ankala Gneiss|Relationships and boundaries|The unit is faulted against Erontonga metamorphics, Utnalaname granulite, and Harry Anorthositic Gabbro, and also against Sliding Rock metamorphics except at Rankin's Prospect (5751-093343), where the two units appear to be conformable.|16-MAY-23
39322|Ankala Gneiss|Age reasons|Middle Proterozoic or older. The first of several metamorphisms recognised in this unit is correlated with the earliest event identified in the Harry Creek area, which is dated at 1800 m.y. using 40Ar-39Ar incremental heating methods (Allen & Stubbs, in press).|16-MAY-23
39322|Ankala Gneiss|Comments|The Ankala gneiss is distinguished from the Utnalanama granulite by its more biotite-rich and calcareous rocks, its lower metamorphic grade and the more acid composition and layered nature of its felsic rocks. The Ankala gneiss lacks the hornblende and garnet-bearing gneisses typical of the Sliding Rock metamorphics.|16-MAY-23
39322|Ankala Gneiss|Proposer|Shaw R.D., Allen A.R. (in Shaw et al., in preparation)|16-MAY-23
466|Anmatjira Orthogneiss|Name source|Anmatjira Range (5453-780480), northern part of Reynolds Range 1:100 000 Sheet area.|16-MAY-23
466|Anmatjira Orthogneiss|Unit history|Large mappable batholith with distinctive rapakivi texture; referred to as Napperby Granite by Australian Geophysical (1967); distinguished and briefly described by Evans & Glikson (1969) as granitic gneiss (orthogneiss) of the Precambrian basement to the Ngalia Basin. Mapped as 'Precambrian orthogneiss, gneissic granite' by Wells et al. (1971).|16-MAY-23
466|Anmatjira Orthogneiss|Type section locality|Ingallan Spring (5453-793499), northeastern side of Anmatjira Range; well exposed rock bars in bed of creek.|16-MAY-23
466|Anmatjira Orthogneiss|Extent|Along entire northeastern flank of Anmatjira Range; also northeastern flank of Yundurbulu Range (5454-520700), Mount Peake 1:100 000 Sheet area.|16-MAY-23
466|Anmatjira Orthogneiss|Lithology|Coarse porphyritic granitic augen gneiss, comprising ovoids of microcline up to 10 cm across and smaller subhedral rapakivi feldspars (microcline mantled by plagioclase) in granitic groundmass.|16-MAY-23
466|Anmatjira Orthogneiss|Relationships and boundaries|Intrudes Tyson Creek granulite, Weldon metamorphics, Possum Creek Charnockite (probably), Lander Rock beds (q.v.), and Mount Stafford beds (q.v.). Intruded by dykes of aplite, pegmatite, microgranite, metamorphosed dolerite, and vein quartz.|16-MAY-23
466|Anmatjira Orthogneiss|Age reasons|Preliminary Rb-Sr wole rock isochron gives 1642 +/- 100 m.y. (Middle Proterozoic) (L.P. Black, BMR, personal communication, 1975).|16-MAY-23
466|Anmatjira Orthogneiss|Proposed publication|2. Commentary on Geology of the Reynolds Range Region (BMR).|16-MAY-23
466|Anmatjira Orthogneiss|Name first published by|Offe L.A., Stewart A.J., 1977|16-MAY-23
72424|Anningie Member|Name source|After Anningie Creek and ANNINGIE mapsheet|16-MAY-23
72424|Anningie Member|Unit history|None.|16-MAY-23
72424|Anningie Member|Geomorphic expression|Locally forms prominent hills, but generally poorly outcropping.|16-MAY-23
72424|Anningie Member|Type section locality|Type area: Northwest of Central Mount in vicinity of 315250mE 7577500mN (21o53'44"S 133o12'46"E) in ANNINGIE.|16-MAY-23
72424|Anningie Member|Extent|Outcrops over an area of about 70 km2 in vicinity of Central Mount and more sporadically over an area of about 90 km2 north of Conical Hill in eastern MOUNT PEAKE. Minor outcrops locally in southern LANDER RIVER (eg 53K 257600mE 7704750mN) are also probable Anningie Member. Interpretation of geophysical data, primarily airborne magnetic, indicate that it is a component of Lander Rock Formation succession throughout northern and eastern MOUNT PEAKE, and LANDER RIVER south of Wiso Basin.|16-MAY-23
72424|Anningie Member|Thickness range|Polydeformation precludes precise determination, but estimated to be <=1200 m.Type area: Northwest of Central Mount in vicinity of 315250mE 7577500mN (21o53'44"S 133o12'46"E) in ANNINGIE.|16-MAY-23
72424|Anningie Member|Lithology|Predominantly micaceous fine-grained quartzo-feldspathic schist; local sillimanite schist apparently proximal to contacts with intrusive mafic rocks; layer-parallel ortho-amphibolite.|16-MAY-23
72424|Anningie Member|Depositional environment|Probably offshore marine.|16-MAY-23
72424|Anningie Member|Relationships and boundaries|Contacts with immediately under- and overlying intervals of Lander Rock Formation not exposed. Airborne magnetic data indicate that Anningie Member is at lower stratigraphic level in Lander Rock Formation than Walabanba Member and is separated from it by undivided Lander Rock Formation. Intruded by Esther Granite and unnamed granite and dolerite.|16-MAY-23
72424|Anningie Member|Structure and Metamorphism|Polydeformed with a generally moderately dipping S1 foliation or locally, bedding.|16-MAY-23
72424|Anningie Member|Age reasons|Late Orosirian. The Walabanba Member, a concordant (and probably conformable) unit at a higher stratigraphic level in Lander Rock Formation, has maximum age of sedimentation of ~1863 Ma based on average of youngest coherent group of zircons (1863 +/- 5 Ma); youngest zircon is 1822 +/- 56 Ma (Claoué-Long et al in press). Intruded by 1789 +/- 6 Ma (Cross et al 2005) Esther Granite.|16-MAY-23
72424|Anningie Member|Correlations|Probably partially correlates with Woodalla and Mount Stafford Members of Lander Rock Formation. Correlated with part of both Bullion Schist and Ooradidgee Group.|16-MAY-23
72424|Anningie Member|References|*Claoué-Long JC, Edgoose C and Worden KE, in press. A correlation of Arunta Region stratigraphy in central Australia. Precambrian Research.   *Cross A, Claoué-Long JC, Scrimgeour IR, Crispe A and Donnellan N, 2005. Summary of results. Joint NTGS-GA geochronology project: northern Arunta and Tanami regions 2000-2003. Northern Territory Geological Survey, Record 2005-003.|16-MAY-23
513|Aquarium Formation|Name source|Aquarium Spring, around latitude 17o29'S longitude 137o37'20"E at the headwaters of Settlement Creek in Calvert Hills 1:250 000 sheet area.|16-MAY-23
513|Aquarium Formation|Unit history|None|16-MAY-23
513|Aquarium Formation|Geomorphic expression|Mildly resistant and ridge forming (lower half of formation) to recessive with pale brown phototones (upper half). The hornfelsed contact with Settlement Creek Dolerite is relatively resistant|16-MAY-23
513|Aquarium Formation|Type section locality|Jackson et al (1987) nominated Aquarium Spring, around latitude 17o29'S longitude 137o37'20"E at the headwaters of Settlement Creek in Calvert Hills mapsheet as the reference area. This is herein redefined as the type section, running along Bullet Creek between 780700E 8064400N (base) and 781200E 8066800N (top). The latter serves as the upper boundary stratotype. REFERENCE SECTION: reference section A is along the Little Calvert River near Calvert Hills homestead, between 743200E 8088000N (approximate base) and 743400E 8089600N (top) in Calvert Hills mapsheet. Reference section B is the interval 90-290 m in DDH HO1 in the Robinson Dome (691700E 8150700N, Robinson River mapsheet), which comprises an upper hornfelsed contact with the Settlement Creek Dolerite, but does not penetrate the underlying Wununmantyala Sandstone (Rawlings 2002). Drill core is stored in the NTGS Core Library, Darwin, for viewing.|16-MAY-23
513|Aquarium Formation|Extent|Throughout the Wearyan Shelf in Calvert Hills and Robinson River 1:250 000 sheet areas.|16-MAY-23
513|Aquarium Formation|Thickness range|120 (Tawallah Range) and >200 m (Robinson River) (Ahmad and Wygralak 1989, Rawlings 2002)|16-MAY-23
513|Aquarium Formation|Lithology|The Aquarium Formation is an upward-fining sequence that incorporates a lower fine-grained sandstone facies and an upper dolomitic mudstone facies. The lower facies is uniformly fine-grained with thick beds of maroon sandstone with diffuse trough and hummocky cross-stratification (HCS) and local mudclasts, synaeresis cracks, linear and interference megaripples, current lineation, flute casts, runzel and tool marks, glauconite and gypsum pseudomorphs (Rawlings 2002). The upper Aquarium facies is composed of dolomitic, glauconitic, micaceous and ferruginous mudstone and fine-grained sandstone, with scattered intervals of dololutite and dolarenite. Common sedimentary structures are cross-lamination and small cross-beds, current lineation, tool marks, flute and runzel marks, load casts and local HCS. However, the upper 15 m is characterised by fine parallel-laminated red/brown (oxic) mudstone that is massive to locally disrupted, with common halite and anhydrite pseudomorphs. Mudstone within 1-10 m of the Settlement Creek Dolerite is hornfelsed and locally brecciated.|16-MAY-23
513|Aquarium Formation|Relationships and boundaries|Conformably overlies the Wununmantyala Sandstone in the upper Tawallah Group (Rawlings 2002), the boundary marked by a transition from medium-grained to fine-grained sandstone, associated with a distinctive change in bedforms, from trough to hummocky cross-bedded. The top of the Aquarium Formation is an intrusive (ie non-conformable) contact with the Settlement Creek Dolerite, a regionally-extensive sill or set of sills (Rawlings 2002). Prior to intrusion of the dolerite, the Aquarium Formation was in sedimentological continuum with the Wollogorang Formation.|16-MAY-23
513|Aquarium Formation|Age reasons|Constrained only by the underlying basement (>1845 Ma) and overlying Wollogorang Formation (~1730 Ma, Jackson et al 1997). A conformable relationship with the latter suggests its age is closer to 1730-1740 Ma (Rawlings 2002).|16-MAY-23
513|Aquarium Formation|Correlations|The Wuraliwuntya Member of the Wununmantyala Sandstone in the Batten Fault Zone in the Bauhinia Downs and Mount Young 1:250 000 map sheets (Pietsch et al 1991, Haines et al 1993). It also tentatively correlates with the Bonanza Creek, lower McCaw, Dhunganda and Yuduyudu Formations in the northern McArthur Basin in the Mount Marumba and Arnhem Bay-Gove 1:250 000 map sheets (Rawlings et al 1997, Sweet et al 1999).|16-MAY-23
513|Aquarium Formation|Defn author|Redefinition by David Rawlings (~2003) published 2006.|16-MAY-23
513|Aquarium Formation|Comments|The need to redefine this formation arose from the insufficient definition provided by Jackson et al (1987) and from the revised stratigraphic framework emanating from recent (1995-2000) NTGS and NABRE studies. The redefinition incorporates a change in the name of the underlying unit, from Sly Creek Sandstone (Roberts et al 1963, Ahmad and Wygralak 1989) to Wununmantyala Sandstone (Rawlings 1999, Jackson et al 2000). The Wununmantyala Sandstone was defined in the Bauhinia Downs 1:250 000 map sheet by Jackson et al (1987) and Pietsch et al (1991) and thought to be restricted to the Batten Fault Zone. Instead, Wununmantyala Sandstone is now mapped underlying the Aquarium Formation throughout the Wearyan Shelf, while the Sly Creek Sandstone appears to be absent (Jackson et al 2000). The redefinition also formalises the change of name for areas mapped as Aquarium Formation by Pietsch et al (1991) and Haines et al (1993) in the Batten Fault Zone to McDermott Formation (Rawlings 1999, Jackson et al 2000).|16-MAY-23
513|Aquarium Formation|References|Ahmad M. and Wygralak A.S., 1989. Calvert Hills, Northern Territory; 1:250 000 Metallogenic Map Series, sheet SE53-8. Northern Territory Geological Survey, Map and Explanatory Notes. **Haines P.W., Pietsch B.A., Rawlings D.J. and Madigan T.L., 1993. Mount Young, Northern Territory; 1:250 000 Geological Map Series, sheet SD53-15. Northern Territory Geological Survey, Explanatory Notes.**Jackson M.J., Muir M.D. and Plumb K.A., 1987. Geology of the southern McArthur Basin, Northern Territory. Bureau of Mineral Resources, Geology and Geophysics, Bulletin, 220. **Jackson M.J., Page R.W., Southgate P. and Scott D., 1997. Why sequence stratigraphy and not lithostratigraphy for exploration? AGSO Research Newsletter, 26; 20-22. **Jackson M.J., Scott D.L. and Rawlings D.J., 2000. Stratigraphic Framework for the Leichhardt and Calvert Superbasins: review and correlations of the pre-1730 Ma successions between Mt Isa and McArthur River. In: Southgate P.N. (Ed.), Carpentaria-Mt Isa Zinc Belt: basement framework, chronostratigraphy and geodynamic evolution of Proterozoic successions. Australian Journal of Earth Sciences, 47, 3; 381-403. **Pietsch B.A., Rawlings D.J., Creaser P.M., Kruse P.D., Ahmad M., Ferenczi P.A. and Findhammer T.L.R., 1991. Bauhinia Downs, Northern Territory; 1:250 000 Geological Map Series, sheet SE53-3. Northern Territory Geological Survey, Map and Explanatory Notes. **Rawlings D.J., 1999. Stratigraphic resolution of a multi-phase intracratonic basin system: the McArthur Basin, northern Australia. Australian Journal of Earth Sciences, 46, 5; 703-723. **Rawlings D.J., 2002. Sedimentology, volcanology and geodynamics of the Redbank package, northern Australia. CODES, University of Tasmania, Doctoral Thesis. **Rawlings D.J., 2003. Robinson River, Northern Territory; 1:250 000 Geological Map Series, sheet SE53-4. Northern Territory Geological Survey, Map and Explanatory Notes. **Rawlings D.J., Haines P.W., Madigan T.L., Pietsch B.A., Sweet I.P., Plumb K.A. and Krassay A.A., 1997. Arnhem Bay-Gove, Northern Territory; 1:250 000 Geological Map Series, sheet SD53-3/4. Northern Territory Geological Survey-Australian Geological Survey Organisation (NGMA), Explanatory Notes. **Roberts H.G., Rhodes J.M. and Yates K.R., 1963. Calvert Hills, N.T.; 1:250,000 geological series, sheet SE53-8. Bureau of Mineral Resources, Geology and Geophysics, Map and Explanatory Notes. **Sweet I.P., Brakel A.T., Rawlings D.J., Haines P.W., Plumb K.A. and Wygralak A.S., 1999. Mount Marumba, Northern Territory; 1:250 000 Geological Map Series, sheet SD53-6. Australian Geological Survey Organisation-Northern Territory Geological Survey (NGMA), Map and Explanatory Notes.|16-MAY-23
24163|Arabulja Volcanics|Name source|Arabulja Waterhole on Murray Creek, at GR 335695, Murray Downs 1:100 000 Sheet area, barrow Creek 1:250 000 Sheet area.|16-MAY-23
24163|Arabulja Volcanics|Type section locality|1.5 km north of Coulters Waterhole (latitude 20o59'55"S, longitude 135o01'50"E) in SW Hatches 1:100 000 Sheet area, from GR 024797 (base) to GR 028797 (top). Here the formation consists of two felsic lava flows dipping about 50o east, conformably overlying feldspathic arenite of the Yeeradgi Sandstone and overlain conformably by quartz arenite of the Coulters Sandstone.|16-MAY-23
24163|Arabulja Volcanics|Extent|NE part of Murray Downs 1:100 0000 Sheet area and adjoining parts of sheet areas: SE part of Davenport Range (Bonney Well 1:250 000 Sheet area), SW part of Hatches (Free River 1:250 000 Sheet area) (NW part of Elkedra 1:250 000 Sheet area) 1:100 000 Sheet areas.|16-MAY-23
24163|Arabulja Volcanics|Thickness range|0 to about 700 m; about 300 m in type section.|16-MAY-23
24163|Arabulja Volcanics|Lithology|Moderately recessive, pinkish, purplish, and reddish-brown felsic lava generally containing phenocrysts up to 5 mm across of alkali feldspar (largely altered) and possible olivine (pseudomorphed) in a very fine-grained quartzofeldspathic groundmass; minor tuff. Lava flows show platy jointing in lower parts and contorted flow-banding in upper parts, and commonly have rubbly (scoriaceous) margins.|16-MAY-23
24163|Arabulja Volcanics|Relationships and boundaries|Conformable on Yeeradgi Sandstone and overlain conformably by Coulters Sandstone. Boundaries taken at abrupt contacts between felsic volcanics and underlying and overlying arenites.|16-MAY-23
24163|Arabulja Volcanics|Age reasons|Younger than 1870 m.y. - U-Pb zircon age of volcanics in the Warramunga Group, which is overlain unconformably by the Hatches Creek Group: Older than 1640 m.y. - Rb-Sr whole rock approximate age of granite intruding the Hatches Creek Group.|16-MAY-23
24163|Arabulja Volcanics|Comments|A readily mappable recessive formation of felsic lavas which differ petrographically (e.g. in phenocryst content) from those of other volcanic formations within the Hatches Creek Group. Part of the Wauchope Subgroup of the Hatches Creek Group.|16-MAY-23
524|Aralka Formation|Name source|Mount Aralka in HALE RIVER at GDA94 53J 548820mE 7343634mN|16-MAY-23
524|Aralka Formation|Name source|Mount Aralka on the Hale River 1:250 000 Sheet area (SG/53-3) (Mount Aralka longitude 135o29'08"E, 24o00'57"S).|16-MAY-23
524|Aralka Formation|Unit history|The Aralka Formation was originally included in the basal part of the Pertatataka Formation by Wells et al. (1967). The Olympic Formation (formerly Olympic Member of the Pertatatataka Formation) is postulated to be laterally continuous with the Pioneer Sandstone (formerly the upper unit of the Areyonga Formation) and hence it was concluded that the interval between the Olympic and Areyonga Formation in the northeast part of the Amadeus Basin is a previously unrecognised separate formation, older than the Pertatataka Formation and should be formalised.|16-MAY-23
524|Aralka Formation|Constituents|Ringwood Member, Limbla Member|16-MAY-23
524|Aralka Formation|Geomorphic expression|Makes up creek and river banks, and is generally recessive on flat-lying plains where it is covered with modern sands and soils.|16-MAY-23
524|Aralka Formation|Type section locality|Type section is indicated by Preiss et al (1978) to be the part of the measured section ASR4 shown in Plate 10 of Wells et al. (1967) between the Areyonga Formation and what was then the Olympic Member of the Pertatataka Formation. The ASR 4 section was originally described as 'about 5 miles SE of Ringwood homestead', and the location indicated in fig3. p8 (Wells et al., 1967). The section corresponds to a ridge approximately 1.4 km east of Halfway Dam (approximate GDA94 53K 501637mE 7360086mN).  Two Reference areas are nominated: Lower Aralka Formation reference area includes the banks of Gypsum Creek (53K 511044mE 7350860mN) which is approximately 1.5 km northeast of Waldo Pedlar Bore. Upper Aralka Formation reference area is a ridge at GDA94 53J 500297mE 7338533mN approximately 11 km southeast of Olympic Bore.|16-MAY-23
524|Aralka Formation|Type section locality|The type section ASR 4 lies 6.4 km southeast of Ringwood Homestead at Longitude 135o02'E latitude 23o53'S, on Alice Springs K17 photos Run 13/Photo 5136. The shale sequences in the formation are mostly obscured but the Ringwood and Limbla Members are well exposed.|16-MAY-23
524|Aralka Formation|Description at type locality|The type section is - TOP 144 m Limbla Member - festoon cross-laminated sandstone in upper half; pebbly and sandy calcarenite in lower half. 333 m concealed - siltstone and shale sequence with minor sandstone interbeds inferred from partial exposures elsewhere. 166 m Ringwood Member - dolomite and calcarenite, mostly thin bedded, in part pisolitic and stromatolitic. 376 m +/- concealed -siltstone and shale sequence with subordinate sandstone interbeds inferred from partial exposures elsewhere.|16-MAY-23
524|Aralka Formation|Description at type locality|Description at reference localities: Lower Aralka Formation: The banks of Gypsum Creek area are high creek banks of laminated, thinly-bedded fine-grained calcareous green siltstone. The siltstone is interbeddedwith fine-grained sandstone beds in exposures where the Ringwood Member is proximal. The siltstone becomes progressively dolomitic, alternating with dolostone beds until the dolostone beds become dominant. Occasional large-scale ripples were observed parallel to the bedding plane, with minor cross bedding evident. The contact with the overlying Ringwood Member is transitional. Upper Aralka Formation: The exposures in the reference area are an succession which comprises dekametre-scale reddish-brown and green siltstone,overlain by metre scale interval of thickly-bedded to massive sandstone, and metre-scale red-brown siltstone. The uppermost interval of red-brown siltstones are overlain by thickly-bedded to massive sandstones. Between these massive sandstones and the topmost shale,  three `calcrete¿ horizons are interlayered with two centimetre-scale- bedded sandstones, suggesting the  occurrence of carbonate rocks (limestone, or carbonate cemented sandstone) interbedded with the sandstones at the contact between the Aralka and Limbla formations.|16-MAY-23
524|Aralka Formation|Extent|The mapped Aralka Formation is confined to the northeastern part of the Amadeus Basin and is known in outcrop on the ALICE SPRINGS, ILLOGWA CREEK, RODINGA and HALE RIVER. Silcified siltstone and calcareous sandstone has been identified as Aralka on HENBURY (Donnellan and Normington in prep)|16-MAY-23
524|Aralka Formation|Extent|The formation is known in outcrop on the Alice Springs, Illogwa Creek, Rodinga, and Hale River 1:250 000 Sheet areas; it is confined to the north-eastern part of the Amadeus Basin.|16-MAY-23
524|Aralka Formation|Thickness range|The thickness in the type section is about 1020 m. The formation thickens gradually eastwards but thins rapidly westwards and is not known in outcrop west of about longitude 134o30'E.|16-MAY-23
524|Aralka Formation|Thickness range|At the type section, the Aralka Formation is approximately 1020 m thick (Preiss et al 1978).  In the lower Aralka Formation reference section thickness is up to about 10 m. In the upper Aralka Formation reference section the unit is up to 63m thick. The unit thickens gradually to the east and thins rapidly towards the west (Preiss et al 1978), approximately 20 m of the unit is in Wallara-1.|16-MAY-23
524|Aralka Formation|Lithology|The sequence of rock types in the type section ASR 4 is shown in Wells et al. (1967), Plate 10, and in addition is described in the text of the report.|16-MAY-23
524|Aralka Formation|Lithology|The grey-green to red siltstone and shale of the Aralka Formation has minor interbeds of fine-grained sandstone. The unit is laminated to finely-bedded in metre to dekametre- scale bedsets, exposures are flaggy and platy. The unit is occasionally calcareous or dolomitic.|16-MAY-23
524|Aralka Formation|Depositional environment|The Aralka Formation was deposited during the widespread flooding event that is related to the marine incursion following the deglaciation of the Sturtian glaciation (Munson et al 2013). The deposition of the siltstone, sandstone and shale units is likely to be in a low energy, shallow marine environment (Edgoose 2013). Thicker shale units at the base of the Aralka Formation may be a result of an initial eustatic rise that occurred directly after the deglaciation. The deposition of the shallow water carbonate and siliciclastic members may be the result of isostatic rebound (Walter et al 1995).|16-MAY-23
524|Aralka Formation|Relationships and boundaries|Aralka Formation conformably overlies Areyonga Formation and is disconformably overlain by Olympic Formation. Where Areyonga Formation is missing, Preiss et al (1978) inferred a disconformable contact between Aralka Formation and Bitter Springs Group. The upper Limbla member is disconformably overlain by Olympic Formation.|16-MAY-23
524|Aralka Formation|Relationships and boundaries|The formation conformably overlies the Areyonga Formation and is disconformably overlain by the Olympic Formation. The upper boundary is exposed in the type section but the lower boundary is concealed. A stratotype lower boundary is present on the north flank of the Limbla Syncline (longitude 135o17'30" E, latitude 23o47'30"S) where the upper marker cap dolomite of the Areyonga Formation is in contact with shale of the Aralka Formation. A stratotype upper boundary is present in the north west part of the Olympic Syncline (longitude 135o02'30"E 21o01'40"S) where cross laminated sandstone of the Limbla Member is in contact with dark red-brown poorly laminated siltstone and light green-grey, locally gritty, siltstone, of the Olympic Member. A disconformable contact with the Bitter Springs Formation is inferred in areas where the Areyonga Formation is absent.|16-MAY-23
524|Aralka Formation|Structure and Metamorphism|The Aralka Formation is not generally affected by structure and metamorphism due to the dominantly siltstone lithology, when subjected to structural force the unit is generally eroded away.|16-MAY-23
524|Aralka Formation|Age reasons|Based on stratigraphic position overlying the Sturtian glacial succession, the age of the Aralka Formation is estimated to be approximately 0.6 Ga (Edgoose 2013). This is supported by Re-Os geochronology results from samples taken within the Wallara-1 drill hole that yielded ages of 658 +/- 5 Ma (Kendall and Creaser 2004) and 657.2 +/- 5.4 Ma (Kendall et al 2006).|16-MAY-23
524|Aralka Formation|Age reasons|The Aralka Formation lies between formations that are considered to be Adelaidean in age. The Bitter Springs Formation beneath is considered to be no older than about 900 m.y. and shales in the younger Pertatataka Formation have been dated radiometrically at 730 +/- 45 m.y. The Aralka Formation is therefore probably mid-Adelaidean in age.|16-MAY-23
524|Aralka Formation|Correlations|Aralka Formation is correlated with the Rinkabeena Shale in the Ngalia Basin, and with the the lower interval of the Inindia beds (Munson et al 2013). Carbonate concretion-bearing shales at the base of Aralka Formation (Walter et al 1995) may correlate with cap dolomite at the top of Nabarula Formation in the Ngalia Basin. Underlying the carbonate Nabarula Formation comprises diamictite and shale. Walter and Veevers (2000) correlate Aralka Formation with Tapley Hill Formation (including the Wockerwirra Member) of the Umbertana Subroup of the Heysen Supergroup. The flaggy dolomitic Wockerawirra Member of the Tapley Hill Formation may correlate with undivided carbonate interbeds in the Aralka Formation unnamed siltstones.|16-MAY-23
524|Aralka Formation|Alteration and Mineralisation|Lead-Zinc-Silver Mineralisation: 2 unnamed occurrences in the Aralka Formation (mapped as Ringwood Member) in the Limbla Syncline, ILLOGWA CREEK (Edgoose 2013). Copper Mineralisation prospect at Waldo Pedlar Bore, ILLOGWA CREEK has been reported to be hosted in the Aralka Formation (Edgoose 2013). Petroleum: Included in 2nd Petroleum system of Marshall et al (2007), the Aralka Formation shows good source rock potential and may be a potential unconventional petroleum source rock (Munson 2014)|16-MAY-23
524|Aralka Formation|Defn author|VJ Normington, N Donnellan 28-SEP-2015. approved by:  Daniel Revie and Verity Normington, NT  Stratigraphic Names Subcommittee 29-SEP-2015.|16-MAY-23
524|Aralka Formation|References|Donnellan N and Normington V, in prep. Henbury 2nd Edition, Northern Territory, 1: 250,000 Geological Map Sheet. Northern Territory Geological Survey. **Edgoose C, 2013. Amadeus Basin: in Ahmad M and Munson TJ (editors) 'Geology and mineral resources of the Northern Territory; Special Publication 5', Northern Territory Government. **Kendall B, Creaser RA and Selby D, 2006. Re-Os geochronology of postglacial black shales in Australia: Constraints on the timing of 'Sturtian' glaciation. Geology 34, 729-732. **Marshall TR, Dyson IA and Liu Keyu, 2007. Petroleum systems in the Amadeus Basin, central Australia: Were they oil prone?: in Munson TJ and Ambrose GJ (editors) 'Proceedings of the Central Australian Basins Symposium, Alice Springs, 16 - 18th August, 2005'. Alice Springs, Northern Territory Geological Survey, Special Publication 2, 136-146. **Munson TJ, 2014. Petroleum geology and potential of the onshore Northern Territory, 2014, Northern Territory Geological Survey, Report 22. **Munson TJ, Kruse PD and Ahmad M, 2013. Centralian Superbasin: in Ahmad M and Munson TJ (editors) 'Geology and mineral resources of the Northern Territory; Special Publication 5', Northern Territory Government. **Normington VJ and Donnellan N, in prep. Characterisation of the Neoproterozoic stratigraphy of the northeast Amadeus Basin, Northern Territory. : in Northern Territory Geological Survey R (editor). **Preiss WV, Walter MR, Coats RP and Wells AT, 1978. Lithological correlations of Adelaidean glaciogenic rocks in parts of the Amadeus, Ngalia, and Georgina basins. BMR Journal of Australian Geology and Geophysics 3, 43-53. **Walter MR and Veevers JJ, 2000. Neoproterozoic Australia: in Veevers JJ (editor) 'Billion-year earth history of Australia and neighbours in Gondwanaland'. Sydney, Gemoc Press, 131-151. **Walter MR, Veevers JJ, Calver CR and Grey K, 1995. Neoproterozoic stratigraphy of the Centralian Superbasin, Australia. Precambrian Research 73, 173-195. **Wells AT, Ranford LC, Stewart AJ, Cook PJ and Shaw R, 1967. Geology of the north-eastern part of the Amadeus Basin, Northern Territory BMR Report 113, Australia.|16-MAY-23
571|Areyonga Formation|Name source|The Areyonga Formation was first named by Prichard and Quinlan (1962), it was named after the aboriginal community Areyonga which is situated in the Gardiner Range approximately 88 km southwest of Ellery Creek.|16-MAY-23
571|Areyonga Formation|Unit history|Madigan (1932) described the same unit at Ellery Creek as No. 2 quartzite. Prichard and Quinlan (1962) originally described two members of the Areyonga Formation, the upper unit has since been redefined by Preiss et al (1978) as the Pioneer Sandstone.|16-MAY-23
571|Areyonga Formation|Geomorphic expression|Although generally easily eroded and poorly exposed, the Areyonga Formation is typically expressed as low rises and hills with some more prominent ridges being composed of silicified sandstone.|16-MAY-23
571|Areyonga Formation|Type section locality|The top of the Areyonga Formation in the type section at Ellery Creek is taken as the top of a dark grey silty shale with lenses of regularly laminatead dolomite.|16-MAY-23
571|Areyonga Formation|Type section locality|Reference Locality: Mapped exposures of the Areyonga Formation on the outside of the Limbla Syncline including a section that was investigated at the northern end of the syncline (from GDA94 53K 525292mE 7370187mN to GDA94  53K 526795mE 7370110mN) as well as an exposure west-southwest of Deadhorse Waterhole (GDA94 53K 518125mE 7372953mN)|16-MAY-23
571|Areyonga Formation|Description at type locality|At reference locality: The reference area consists of 3 broad lithological groups,: diamictite including erratic fields, siliciclastic beds of sandstone and siltstone and carbonate rocks including beds throughout the unit and the cap carbonate rocks.|16-MAY-23
571|Areyonga Formation|Extent|The Areyonga Formation is widespread across the central and northeastern Amadeus Basin. The unit is most extensively mapped on ILLOGWA CREEK and HALE RIVER, and to a lesser extent on ALICE SPRINGS and RODINGA. It is also locally present in outcrop on the HERMANNSBURG and HENBURY sheets.|16-MAY-23
571|Areyonga Formation|Extent|Locally present in outcrop on the Hermannsburg Henbury 1:250 000 Sheet areas, more widespread on the Illogwa Creek, Hale River and to a lesser extent, Alice Springs and Rodinga 1:250 000 Sheet areas.|16-MAY-23
571|Areyonga Formation|General description|The diamictite and siltstone units of the Areyonga Formation are generally sporadically exposed between more prominent ridges of sandstone. Where well consolidated, diamictite units make up rounded hills and rises.|16-MAY-23
571|Areyonga Formation|Thickness range|The redefined Areyonga Formation is 230 m thick.|16-MAY-23
571|Areyonga Formation|Thickness range|The type section has a thickness of about 230 m (750ft, Prichard and Quinlan 1962). It is difficult to ascertain the thickness of the Areyonga Formation from exposures due to the unit's susceptibility to erosion. Wells et al (1967) suggested that the thickness ranges from approximately 350 to 500 m in the Limbla Syncline area and is generally between 10 to 200 m thick elsewhere in the northeast of the basin. The thickness of the unit varies greatly at subsurface levels, a thickness of about 47 m is reported in BR05DD01 (Ambrose et al 2010), approximately 115 m in Wallara-1 (Not-Known and Indigo-Oil-Sirgo-Exploration 1990) and about 163 m in Ooramina-1 (Schmerber 1966). The variability in thickness can also be attributed to the sporadic depositional processes of glacial sediments.|16-MAY-23
571|Areyonga Formation|Lithology|Consists of diamictite, sandstone, dolomitic arkose, conglomerate and dolomite, with the dolomitic silty shale at the top.|16-MAY-23
571|Areyonga Formation|Lithology|Diamictite: The diamictite units observed are buff or green and range from massively to thinly bedded. They are either matrix- or clast-supported or often interbedded with sandstone and siltstone beds. The matrix lithology ranges from silt- to sandstone; the sandstone matrix when present is fine- to very coarse-grained. The matrix regardless of grainsize is often silty or calcareous. The diamictite is poorly to moderately sorted, with clast sizes ranging from < 1cm to 30 cm. Clasts are predominantly subrounded to rounded with also some angular clasts observed. The lithology of the clasts includes carbonate rocks of the Bitter Springs Group, quartzite of the Heavitree Quartzite as well as basement derived rocks such as vein quartz, quartzite, granite and gneiss. Pebble and cobble lenses and beds are common where diamictite outcrops are extensive. Some of the larger clasts are polished and striated. Where diamictite units have been eroded, erratic fields are often the only indicator of their earlier presence. Erratic fields occur generally on flat-lying, alluvium covered landscapes. The clasts and erratics range from 4 cm to over 50 cm, though the average size range is 5 to 20 cm. The erratics are typically rounded and often broken apart.Sandstone and siltstone: Throughout the unit there are a number of coarse- to very coarse-grained sandstone units. The sandstone is generally exposed on hill slopes and at the top of small hills. The sandstone is silicified and in some areas near the base of the unit has been completely ferruginised to form ferricrete. The outcrop types vary from rounded boulders scattered amongst erratics to blocky or flaggy, bedded exposures. In general the red-brown sandstone is immature and poorly sorted with rounded to angular grains. Some sandstone is composed of only rounded grains while others feature only angular grains, while the bedded sandstone outcrops have angular grains or a mixed grain shape. The sandstone is felspathic with up to 25% feldspar observed at one location and other locations the feldspar has weathered to a clay matrix within the sandstone. The sandstone also contains mica and lithics. The lithics are more apparent in the very coarse-grained sandstone and appear to be vein quartz. Where sediments are less silicified, hematite and Fe-oxide staining coats individual quartz grains and black haematitic stains are common on the weathered surfaces. Siltstone beds are less common than sandstone beds, throughout the reference section. Siltstone beds are generally exposed at the base of hill slopes, in incised valleys and creek banks. The green and red siltstones are thinly bedded and laminated; beds are approximately 1cm thick and the exposures are highly weathered. The red siltstone is occasionally disrupted by beds of grey siltstone. Feldspar and some quartz grains are visible in the siltstone.Carbonate: Exposures up to 40 m of highly weathered carbonate rock occur at the northern end of the measured section on the Limbla Syncline. The yellow carbonate has the weathering texture typical of the carbonate rocks of the Bitter Springs Group, however, fresh surfaces show that the carbonate has been completely replaced to form silcrete. The fresh surface is pink with quartz grains, white feldspar and black heavy minerals (possible hematite) preserved within the cherty matrix. These silcreted carbonate exposures occur between the sandstone bed exposures, however a contact was not observed. There were no carbonate beds observed in the upper part of the section.|16-MAY-23
571|Areyonga Formation|Depositional environment|The alternating sandstone and carbonate beds in the lower part of the section are indicative of an alternating fluvioglacial and glaciomarine setting after an initial glacial deposition of a basal diamictite. The carbonate beds stop and erratic fields and diamictite alternate with sandstone beds. This is indicative of a probable shift in climate and depositional setting. The sandstone beds are likely representative of a fluvioglacial depositional setting while the diamictite and erratic fields are indicative of period of a colder glacial period. Given the rounded clasts in the diamictite and erratic fields it is likely that during the glacial periods the environment was warm enough that meltwater streams were common and hence providing a mechanism to round and polish the clasts. Towards the top of the section sandstone beds get thicker and the recessive parts in between have no erratics. Walter et al (1995) suggested that the glaciation entered the basin from the northeast as two large ice tongues.|16-MAY-23
571|Areyonga Formation|Relationships and boundaries|Due to the scouring that occurred during Sturtian glaciation, the Areyonga Formation disconformably cuts into different levels of the underlying strata. In the northeastern portion of the basin, the Areyonga Formation was observed to be unconformably overlying the Gillen, Loves Creek, and Johnnys Creek formations. At Ellery Creek, the Wallara Formation is  overlain by weathered diamictite of the Areyonga Formation, this is likely an unconformable contact however the contact is not exposed at Ellery Creek. The upper contact with the Aralka Formation was observed in the Limbla Syncline area in a small creek bank, the contact is transitional.|16-MAY-23
571|Areyonga Formation|Identifying features|The Areyonga Formation consists typically of poorly exposed diamictite. Remnants of the eroded diamictite are often expressed as erratic fields, where larger clasts remain after the matrix of the diamictite has eroded. Clasts are most often quartzite and basement rocks, some are polished and striated. Beds of sandstone, siltstone and carbonate occur throughout the unit. Distinguishing between the Areyonga Formation and other glacial units within the basin is [?]|16-MAY-23
571|Areyonga Formation|Structure and Metamorphism|The Areyonga Formation is generally locally faulted and folded, however it is largely unconsolidated and therefore more likely to erode than to preserve any structure.|16-MAY-23
571|Areyonga Formation|Age reasons|The Areyonga Formation has been correlated with other glacial successions in the Neoproterozoic due to the lithological similarities and presence of a thin carbonate cap at the top of the formation. The Sturtian glaciation lasted from about 720 to 660 Ma, therefore the Areyonga Formation is constrained to this age. Recent U-Pb isotope studies (Kositcin et al 2014) on detrital zircon grains from a sandstone bed within the Areyonga Formation yielded a maximum depositional age of 876 +/- 14 Ma; this is considerably older than the suggested sedimentation age of the formation.|16-MAY-23
571|Areyonga Formation|Correlations|Equivalent to the lower most part of the Inindia beds in the south and southwest of the basin. Outside of the basin, the Areyonga Formation is correlative to the Naburula Formation in the Ngalia Basin, the Mount Cornish Formation and Yardida Tillite in the Georgina Basin (Munson et al 2013) and with the Sturt Tillite and its equvialents in the Adelaide Fold Belt (Preiss et al 1978).|16-MAY-23
571|Areyonga Formation|Alteration and Mineralisation|Copper: Surface expression of copper mineralisation in the form of malachite, azurite and chalcocite  has been observed at Ringwood (HALE RIVER). Subsequent drilling identified mineralisation with assay results up to 2500 ppm of Cu (Youles 1966).  Petroleum: The Areyonga Formation is part of the middle Neoproterozoic petroleum system, however there is no indication of any potential petroleum source within the formation (Munson 2014).|16-MAY-23
571|Areyonga Formation|Defn author|VJ Normington, N Donnellan 28-SEP-2015.  Approved: Stefan Kraus and Verity Normington 9-Oct-2015.|16-MAY-23
571|Areyonga Formation|Defn author|Preiss W.V., Walter, M.R., Coats R.P., Wells A.T., 1978|16-MAY-23
571|Areyonga Formation|Comments|The recognised type section is at Ellery Creek as proposed by Preiss et al (1978). Described are here 250 m of diamictite, sandstone, dolomitic arkose, conglomerate and dolomite with dolomitic silty shale at the top. The addition of the reference section is necessary due to the variable lithology types in the Areyonga Formation. The reference area includes several different lithofacies including diamictite, siltstone and sandstone units.|16-MAY-23
571|Areyonga Formation|Comments|Prichard and Quinlan (1962) recognised two members in the Areyonga Formation in its type section. A disconformity has now been recognised separating these members. The upper member is redefined as the Pioneer Sandstone (new name). The name Areyonga Formation is restricted to the lower member, with which it is conveniently associated.|24-JUN-23
571|Areyonga Formation|References|Ambrose GJ, Dunster JN, Munson TJ and Edgoose CJ, 2010. Well completion reports for NTGS stratigraphic drillholes LA05DD01 and BR05DD01, southwestern Amadeus Basin: in Northern Territory Geological Survey R- (editor). **Kositcin N, Normington V and Edgoose C, 2014. Summary of results. Joint NTGS-GA geochronology project: Amadeus Basin, July 2013-June 2014. NTGS Record 2015-001, Northern Territory Geological Survey. **Madigan CT, 1932. The geology of the western MacDonnell Ranges, central Australia. Quarterly Journal of the Geological Society of London 88, 672-711. **Munson TJ, 2014. Petroleum geology and potential of the onshore Northern Territory, 2014, Northern Territory Geological Survey, Report 22. **Munson TJ, Kruse PD and Ahmad M, 2013. Centralian Superbasin: in Ahmad M and Munson TJ (editors) 'Geology and mineral resources of the Northern Territory; Special Publication 5', Northern Territory Government. **Normington VJ and Donnellan N, in prep. Characterisation of the Neoproterozoic stratigraphy of the northeast Amadeus Basin, Northern Territory. Record 2015-##, Northern Territory Geological Survey. **Not-Known and Indigo-Oil-Sirgo-Exploration, 1990. Wallara-1 Well Completion Report. **Preiss WV, Walter MR, Coats RP and Wells AT, 1978. Lithological correlations of Adelaidean glaciogenic rocks in parts of the Amadeus, Ngalia, and Georgina basins. BMR Journal of Australian Geology and Geophysics 3, 43-53. **Prichard CE and Quinlan T, 1962. The geology of the southern half of the Hermannsburg 1:250 000 sheet. BMR Report No. 61. Bureau of Mineral Resources Geology and Geophysics. **Schmerber G, 1966. A petrological study of the sediments from Ooraminna No. 1 well, Amadeus Basin, Northern Territory, Bureau of Mineral Resources, Geology and Geophysics Record 1966-82. **Walter MR, Veevers JJ, Calver CR and Grey K, 1995. Neoproterozoic stratigraphy of the Centralian Superbasin, Australia. Precambrian Research 73, 173-195. **Wells AT, Ranford LC, Stewart AJ, Cook PJ and Shaw R, 1967. Geology of the north-eastern part of the Amadeus Basin, Northern Territory BMR Report 113, Australia. **Youles LP, 1966. Diamond Drill Report Undoolya Gap Copper Prospect NTGS Technical Report 1966-001: in Survey NTG (editor), Northern Territory Government.|24-JUN-23
37960|Aroota Group|Name source|From Aroota Bore, adjacent to extensive outcrop of Yardida Tillite in the Field River Anticline, northeastern HAY RIVER.|16-MAY-23
37960|Aroota Group|Unit history|Glacial unit of Field River beds (Smith 1963a); Mount Cornish beds (Shergold and Druce 1980).|16-MAY-23
37960|Aroota Group|Constituents|Yardida Tillite, Mount Cornish Formation, possibly basal diamictite of Central Mount Stuart Formation (Preiss et al 1978, Walter 1981).|16-MAY-23
37960|Aroota Group|Extent|HAY RIVER, TOBERMORY and HUCKITTA.|16-MAY-23
37960|Aroota Group|Relationships and boundaries|Nonconformable on Jinka Granite. Overlies Yackah beds of Plenty Group with inferred disconformity. Disconformably overlain by Black Stump Arkose and Oorabra Arkose of Keepera Group.|16-MAY-23
37960|Aroota Group|Age reasons|Lower of two late Neoproterozoic glacigene units; correlated with Sturtian glaciation in Adelaide Rift (Preiss et al 1978).|16-MAY-23
37960|Aroota Group|Correlations|Areyonga Formation of Amadeus Basin, Naburula Formation of Ngalia Basin (Smith 1964, Walter 1981, Freeman 1986).|16-MAY-23
37960|Aroota Group|Comments|Basal diamictite of Central Mount Stuart Formation (Preiss et al 1978, Walter 1981) may alternatively be part of Boko Formation of Haines et al (1991) and therefore a constituent of the Keepera Group.|16-MAY-23
75503|Arrarra Gneiss|Name source|After the Arrarra U-Au prospect in the Alligator River Uranium Field:  12o12'37.4'S 132o51'34.5"E (GDA 94 Zone 53 267130mE 8649261mN); Alligator River 1:250 000 scale mapsheet; Oenpelli 1:100 000 scale mapsheet, Nimbuwah Domain, Pine Creek Orogen, western Arnhem Land, Northern Territory.|16-MAY-23
75503|Arrarra Gneiss|Unit history|Previously known as part of Myra Falls Metamorphics. The name 'Myra Falls Metamorphics' was first introduced by Dunn (1962) to describe metamorphic rocks in the Oenpelli area (now often referred to as Kunbarllanjnja or Gunbalanya) which were then considered to be Archaean. Subsequent work by Needham et al (1974) suggested these rocks were Palaeoproterozoic. The name 'Myra Falls Metamorphics' is abandoned, as it is now known to comprise components of the Palaeoproterozoic Kakadu Group, Cahill Formation and Neoarchaean gneissic basement (Hollis et al 2009, in press).|16-MAY-23
75503|Arrarra Gneiss|Geomorphic expression|Low-lying areas exposed in creek systems. Exposures have white tones in aerial photographs.|16-MAY-23
75503|Arrarra Gneiss|Type section locality|Exposed fresh boulder outcrop below incised Cenozoic sand cover in the Arrarra area, about 14 km northeast of Oenpelli. Alligator River 1:250 000 mapsheet, Oenpelli 1:100 000 mapsheet. Grid reference: GDA 94, 53L 295877mE 8648940mN (12°12'55"S 133°7'25"E).|16-MAY-23
75503|Arrarra Gneiss|Type section locality|Type Area: Exposed fresh boulder outcrop below incised Cenozoic sand cover in the Arrarra area, about 14 km northeast of Oenpelli. Alligator River 1:250 000 scale mapsheet, Oenpelli 1:100 000 scale mapsheet. Grid reference:  12o12'54.80"S, 133o7'25.30"E (GDA 94, Zone 53, 295877mE 8648940mN).|16-MAY-23
75503|Arrarra Gneiss|Description at type locality|Arrarra Gneiss typically forms low-lying scattered, fresh boulder outcrops below incised Cenozoic sand cover. Granitic gneiss in the type area preserves a well developed S2 gneissosity defined by quartzo-feldspathic- and biotite-rich cm-scale layers, and by feldspars elongated within the fabric. A moderately developed feldspar stretching lineation, L2, plunges shallowly to the east-northeast.|16-MAY-23
75503|Arrarra Gneiss|Extent|Oenpelli 1:100 000 scale mapsheet (Alligator River 1:250 000 scale mapsheet), Nimbuwah Domain, Pine Creek Orogen, western Arnhem Land, Northern Territory. Occurs as an isolated weathered exposures in the northeastern Myra Falls Inlier and also as scattered, fresh boulder outcrops exposed through incised Cenozoic sand cover in the Arrarra area, about 14 km northeast of Oenpelli.|16-MAY-23
75503|Arrarra Gneiss|Extent|Restricted distribution over a few square kilometres south of Cooper Creek in Oenpelli 1:100 000 mapsheet (Alligator River 1:250 000 mapsheet), Nimbuwah Domain, Pine Creek Orogen, western Arnhem Land, Northern Territory.|16-MAY-23
75503|Arrarra Gneiss|General description|Occurs as isolated weathered exposures in northeastern Myra Falls Inlier and also as scattered, fresh boulder outcrops exposed through incised Cenozoic sand cover in Arrarra area, about 14 km northeast of Oenpelli township.|16-MAY-23
75503|Arrarra Gneiss|Thickness range|Unknown due to poor exposure|16-MAY-23
75503|Arrarra Gneiss|Lithology|In the type area, the Arrarra Gneiss typically forms low-lying scattered, fresh boulder outcrops below incised Cenozoic sand cover. Granitic gneiss in the type area preserves a well developed S2 gneissosity defined by quartzo-feldspathic and biotite-rich cm-scale layers, and by feldspars elongated within the fabric. A moderately developed feldspar stretching lineation, L2, plunges shallowly to the east-northeast. In the northeastern Myra Falls Inlier, the rocks show moderate gneissic compositional layering and are locally isoclinally folded, Hollis et al (in press).|16-MAY-23
75503|Arrarra Gneiss|Lithology|Quartzo-feldspathic gneiss|16-MAY-23
75503|Arrarra Gneiss|Depositional environment|Genesis: Metamorphosed intrusive rock.|16-MAY-23
75503|Arrarra Gneiss|Relationships and boundaries|The Arrarra Gneiss is surrounded by younger metasedimentary and mafic igneous intrusive rocks below incised Cenozoic sand cover. The Arrarra Gneiss structurally underlies the Palaeoproterozoic metasedimentary Kudjumarndi Quartzite of the Kakadu Group. Physical boundaries with overlying units are not observed due to generally poor outcrop. The exact nature of the unit boundaries are not possible to define given the poor exposure and structural transposition by later Palaeoproterozoic tectonism, but an unconformable contact is inferred. Stratigraphic relationships are described in detail in Hollis et al (in press).|16-MAY-23
75503|Arrarra Gneiss|Relationships and boundaries|Arrarra Gneiss forms tectonic basement to the Palaeoproterozoic metasedimentary Kudjumarndi Quartzite of the Kakadu Group below incised Cenozoic sand cover. The exact nature of unit boundaries is not possible to define due to poor exposure and structural transposition by later Palaeoproterozoic tectonism. Stratigraphic relationships are described in detail in Hollis et al (2009b)|16-MAY-23
75503|Arrarra Gneiss|Identifying features|The Arrarra Gneiss is distinguished from younger Palaeoproterozoic Nimbuwah granitoids by distinctive metamorphic fabrics, e.g., a well developed gneissosity and moderately developed stretching lineation. It also has a distinctive geochemical signature, characterised by depletion in heavy rare earth elements relative to light rare earth elements (Glass et al 2009).|16-MAY-23
75503|Arrarra Gneiss|Identifying features|Arrarra Gneiss is distinguished from younger Palaeoproterozoic Nimbuwah granitoids by distinctive metamorphic fabrics, eg, a moderately developed gneissosity, and by a distinctive geochemical signature characterised by depletion in heavy rare earth elements (HREE) relative to light rare earth elements (LREE, Glass et al 2009).|16-MAY-23
75503|Arrarra Gneiss|Structure and Metamorphism|Amphibolite-facies metamorphism. Granitic gneiss in type area preserves a well developed S2 gneissosity defined by quartzo-feldspathic and biotite-rich cm-scale layers, and by feldspars elongated within the fabric. A moderately developed feldspar stretching lineation, L2, plunges shallowly to the east-northeast. In the northeastern Myra Falls Inlier, the rocks show moderate gneissic compositional layering and are locally isoclinally folded (Hollis et al 2009b).|16-MAY-23
75503|Arrarra Gneiss|Age reasons|U-Pb SHRIMP zircon ages of 2634 +/- 3 Ma (Worden et al 2006) and 2640 +/- 4 Ma (Hollis et al 2009b, Carson et al 2010), interpreted to represent the primary magmatic crystallisation age of the granitic protoliths.|16-MAY-23
75503|Arrarra Gneiss|Age reasons|U-Pb SHRIMP zircon ages of 2640 ± 4 Ma and 2671 ± 3 Ma (Hollis et al 2009), interpreted to represent the primary magmatic crystallisation age of the granitic protoliths.|16-MAY-23
75503|Arrarra Gneiss|Correlations|No known correlatives|16-MAY-23
75503|Arrarra Gneiss|Correlations|No known correlatives for 2640 +/- 4 Ma quartzo-feldspathic gneiss in the Arrarra region. The Woolner Granite (2675 +/- 28 Ma; Williams and Compston 1983) in the Central Domain of the Pine Creek Orogen is a correlative of the 2671+/- 4 Ma quartzo-feldspathic gneiss in the northeast Myra Falls Inlier.|16-MAY-23
75503|Arrarra Gneiss|Alteration and Mineralisation|Sericitisation of plagioclase feldspar and chlorite alteration of hornblende. No known mineralisation.|16-MAY-23
75503|Arrarra Gneiss|Geophysical Expression|Laterite covering concealed Arrarra Gneiss has a positive radiometric response|16-MAY-23
75503|Arrarra Gneiss|Geochemistry|Exhibits a distinctive geochemical signature characterised by depletion in HREE relative to LREE (Glass et al 2009). Samples are mostly peraluminous with silica values relatively constant at ca 70 wt% SiO2 and ca 3.5 wt% Na2O. The Arrarra Gneiss has a juvenile Nd isotopic signature (epsilon Nd = 2.9).|16-MAY-23
75503|Arrarra Gneiss|Defn author|Hollis, J.A., Glass, L. M. (NTGS)  03-NOV-2010|16-MAY-23
75503|Arrarra Gneiss|Defn author|Hollis, J.A. (NTGS)  24-AUG-2009|16-MAY-23
75503|Arrarra Gneiss|Comments|Redefinition provides refined age dates and improved and additional unit description.|16-MAY-23
75503|Arrarra Gneiss|References|**CARSON CJ, Hollis JA, Glass LM, Close DF, Whelan JA and Wygralak A, 2010. Summary of results. Joint NTGS-GA geochronology project: East Arunta Region, Pine Creek Orogen and Murphy Inlier, July 2007¿June 2009. Northern Territory Geological Survey, Record 2010-004.    **DUNN PR, 1962. Alligator River, Northern Territory. 1:250 000 geological series explanatory notes, SD53¿01. Bureau of Mineral Resources, Australia, Canberra.    **GLASS LM, Hollis JA and Carson CJ, 2009. Geochemical and isotopic discrimination methods for Neoarchaean and Palaeoproterozoic rocks in western Arnhem Land, Pine Creek Orogen: Applications for uranium exploration: in 'Annual Geoscience Exploration Seminar (AGES) 2009. Record of Abstracts'. Northern Territory Geological Survey, Record 2009-002.     **HOLLIS JA, Carson CJ and Glass LM, 2009a. Extensive exposed Neoarchaean crust in Arnhem Land, Pine Creek Orogen: U-Pb zircon SHRIMP geochronology: in 'Annual Geoscience Exploration Seminar (AGES) 2009. Record of Abstracts'. Northern Territory Geological Survey, Record 2009-002.    **HOLLIS JA, Carson CJ and Glass LM, 2009b. SHRIMP U-Pb zircon geochronological evidence for Neoarchean basement in western Arnhem Land, northern Australia. Precambrian Research 174(3¿4), 364¿380.    **HOLLIS JA, Schérsten A, Glass LM, Carson CJ, 2009c. Stratigraphic and tectonic evolution of the Nimbuwah Domain: a separate terrane to the rest of the Pine Creek Orogen?: in 'Annual Geoscience Exploration Seminar (AGES) 2009. Record of Abstracts'.  Northern Territory Geological Survey, Record 2009-002.    **NEEDHAM RS, Smart PG and Watchman AL, 1974. A Reinterpretation of the geology of the Alligator Rivers uranium field, NT. Search 5(8), 397¿399.    **WORDEN KE, Claoué-Long JC, Scrimgeour IR, and Doyle N, 2006. Summary of results. Joint NTGS-GA geochronology project: Pine Creek Orogen and Arunta Region, January¿June 2004. Northern Territory Geological Survey, Record 2006-005.|16-MAY-23
75503|Arrarra Gneiss|References|**DUNN, P.R., 1962. Alligator River, Northern Territory. 1:250 000 geological series explanatory notes, SD53-01. Bureau of Mineral Resources, Australia, Canberra.  **GLASS L.M., Hollis J.A. and Carson C.J., 2009. Geochemical and isotopic discrimination methods for Neoarchaean and Palaeoproterozoic rocks in western Arnhem Land, Pine Creek Orogen: Applications for uranium exploration: in Annual Geoscience Exploration Seminar (AGES). Record of Abstracts. Northern Territory Geological Survey, Record 2009-002.   **HOLLIS J.A., Carson C.J. and Glass L.M., 2009. Extensive exposed Neoarchaean crust in Arnhem Land, Pine Creek Orogen: U-Pb zircon SHRIMP geochronology: in Annual Geoscience Exploration Seminar (AGES). Record of Abstracts. Northern Territory Geological Survey, Record 2009-002.   **HOLLIS J.A., Carson C.J. and Glass L.M., in press. SHRIMP U-Pb zircon geochronological evidence for Neoarchaean basement in western Arnhem Land, northern Australia. Precambrian Research.   **NEEDHAM, R.S, Smart, P.G. and Watchman, A.L., 1974. A Reinterpretation of the geology of the Alligator Rivers uranium field, N.T. Search, 5(8), 397-399.   **WILLIAMS, I.S. and Compston, W., 1983. Ion microprobe U-Pb dating of zircons recovered from granitoids in core from drill holes P4/1D, P11/1, P12/11, and P14/1, Woolner, Northern Territory: in Manning, E.R., Richardson, B.R., Starkey, L.J. (editors) Annual report for EL 3478 "Woolner" for the 12 months to June 17, 1983, Volume 1, Mobil Energy Minerals Australia Inc. Northern Territory Geological Survey, Open File Company Report CR1983-0231A.|16-MAY-23
645|Arthur Creek Formation|Name source|Originally defined by K.G. Smith (Progress Report on the Geology of the Huckitta 1:250 000 sheet, Bureau of Mineral Resources Report 67, 1964) as Arthur Creek Beds because of its poor outcrop and a suspected break in the sequence. Following stratigraphic diamond drilling in 1982 and the fact that the break is not evident, it is now desirable to elevate the unit to formation status.|16-MAY-23
645|Arthur Creek Formation|Unit history|Now excludes dolomite in Smith's (op. cit.) western outcrops which are assigned to either the Arrinthrunga or Errarra Formations. Probably partly equivalent to the Sandover beds on the Elkedra sheet (north) and the Marqua beds on the Tobermory sheet (east).|16-MAY-23
645|Arthur Creek Formation|Type section locality|Holostratotype: in two, overlapping, continuously-cored holes:- DDH. NTGS. HUC2, for upper part, from 20.35 m to 203.76 m depth and DDH. NTGS. HUC 1, for lower part, from 9.17 m to 310.73 m depth. Core will be stored in NTGS core store, Alice Springs. Overlap of the two holes is correlated using the lowest occurrence of limestone beds, a distinctive marker within the formation. Lateral facies variations may result in minor imprecision of this correlation. (HUC 1 is located at latitude 22o31'50"S, longitude 136o15'4"E. HUC 2 at latitude 22o23'7"S, longitude 136o15'4"E).|16-MAY-23
645|Arthur Creek Formation|Thickness range|484.97 m in holostratotype. Units as below: Top: 1. In DDH. HUC.2, 20.35-74.73 m (54.38 m) Calcareous quartz arenite.  2. HUC   2, 74.73-203.76 m (129.03 m) laminated calcareous siltstone.  Base: Only the lower subdivision occurs in and west of the Elua Ranges (longitude 136oE) and is thinner (order of 100 m).|16-MAY-23
645|Arthur Creek Formation|Lithology|Where fresh, essentially a pyritic, organic-rich, dark grey, laminated, calcareous siltstone with interbeds of limestone and of calcareous quartz arenite. In weathered outcrop a bleached siltstone or, in the west of Huckitta, is replaced by chalcedony. Rarely dolomitic. Most dolomite as recognised by Smith (op. cit) is now assigned to the Arrinthrunga Formation and some to the Errarra Formation. Three recognizable subdivisions as below.|16-MAY-23
645|Arthur Creek Formation|Relationships and boundaries|Gradational at top with dolostones of the Arrinthrunga Formation and at the base with sandstone in the Errarra Formation; in both cases over intervals of approx. 1-2 m.|16-MAY-23
645|Arthur Creek Formation|Age reasons|Middle Cambrian. Faunas suggest a stage range of Floran or older to late Undillan. (Work proceeding by J.R. Laurie, Bureau of Mineral Resources).|16-MAY-23
24166|Atnarpa Igneous Complex|Name source|Atnarpa homestead (GR 5850-783983), situated on tonalite map unit of the Atnarpa Igneous Complex, Fergusson Range 1:100 000 Sheet area.|16-MAY-23
24166|Atnarpa Igneous Complex|Type section locality|Reference areas: 1. From GR 5850-77595 for 3 km eastward to 5850-80595 in Fergusson Range 1:100 000; - well exposed hilly terrain of diorite containing rafts of orthoamphibolite of Tommys Gap metamorphics. Western end shows numerous aplite dykes forming separate aplogranite map-unit. 2. At GR 5850-680923 in Fergusson Range 1:100 000; fresh tors of tonalite with abundant dark xenoliths. 3. GR 5850-695930 in Fergusson Range; granite is well exposed on south bank of unnamed creek. 4. GR 5850-970007 in northeast of Fergusson Range; prominent hills of granodiorite on east bank of Hale River.|16-MAY-23
24166|Atnarpa Igneous Complex|Extent|Northern part of Fergusson Range 1:100 000 Sheet area and southern part of Riddoch 1:100 000 Sheet area N.T. Forms much of basement core of Arltunga Nappe Complex.|16-MAY-23
24166|Atnarpa Igneous Complex|Lithology|Consanquineous igneous complex of diorite-tonalite-granodiorite-granite-aplite-hydrothermal veins (quartz-calcite common). Diorite forms 4 bodies separated by regions of Tommys Gap metamorphics in Giles Creek Synform; is tetrogeneous in mineralogical composition, giving rise to small amounts of such variants as gabbro, tonalite, adamellite, and granite. Tonalite occupies large area in White Range Nappe (central part) and western part of Giles Creek Synform; also mineralogically heterogeneous, forming small amounts of diorite, trandhjemite, granodiorite, adamellite. Retrogressively metamorphosed to mylonitic metatonalite gneiss in root zone of White Range Nappe. Granodiorite map-unit occurs only in Ruby Gap Nappe east of White Range Nappe. Granite forms extensive irregular regions inside tonalite, is coarse and contains roughly equal amounts of albite and microcline. Aplite abundant as dykes and sheets, sufficiently abundant in two areas of the diorite to be mapped as separate areas of aplogranite. Hydrothermal veins mostly intrude the diorite, include quartz-calcite, quartz-calcite-hematite, calcite-epidote.|16-MAY-23
24166|Atnarpa Igneous Complex|Relationships and boundaries|Intrudes orthoamphibolite, hornblende gneiss, and basic volcanic units of Tommys Gap metamorphics (q.v.), surrounds rafts of quartz-rich metasediment and amphibolite of Cavenagh metamorphics (q.v.), sends apophyses in large-scale lit-par-lit fashion into biotite gneiss of Hillsoak Bore metamorphics. Adjoins and presumably intrudes hornblende gneiss, biotite gneiss, and quartzofeldspathic gneiss of unnamed unit pCx in Arunta Block. Is intruded by plugs of ultramafic rock, dykes of amphibolite, dykes of dolerite correlated with Stuart Dyke Swarm. Is unconformably overlain by Heavitree Quartzite.|16-MAY-23
24166|Atnarpa Igneous Complex|Age reasons|Four out of five whole-rock samples lie on Rb-Sr isochron giving 1710+/-50 m.y. in Giles Creek Synform. Two whole-rock samples lie on Rb-Sr isochron (with several other samples from Cavenagh metamorphics, Cadney metamorphics, Jennings Granitic Gneiss) giving 1719+/-24 m.y.|16-MAY-23
24166|Atnarpa Igneous Complex|Comments|Reason for proposed name: Large well-studied well exposed complex of intermediate to acid igneous rocks readily mapped out from adjoining country rocks.|16-MAY-23
25768|Attack Creek Formation|Name source|Attack Creek in the Tennant Creek 1:250 000 Sheet area, latitude 19o03'30"S, longitude 134o03'E.|16-MAY-23
25768|Attack Creek Formation|Type section locality|Between grid references 401893 and 398892. The section here commences with a basal 80 m of cream-coloured calcareous siltstone, medium to thick bedded. There follows 300 m of dark grey flaggy limestone, in part silicified. Thin calcareous siltstone or shale interbeds (1 cm or less) separate 8-10 cm flags of limestone. Some limestone beds contain shaly clasts, siliceous nodules and oolitic concentrations. The limestone grades into 20 m of concretionary ironstone, calcareous black (manganiferous) mudstone and brown and black mottled chert. This is overlain by 200 m of cream to rusty brown feldspathic quartz sandstone and pink to cream silicified orthoquartzite, followed by a sequence 120 m thick of softer rocks, largely eroded, believed to be friable sandstone or siltstone. The upper part of the formation consists of 100 m of massive, thick-bedded, cream orthoquartzite with 1 to 2 percent of well-rounded, pink orthoquartzite pebbles scattered throughout the sandstone matrix; there are voids left by weathered-out shale clasts.|16-MAY-23
25768|Attack Creek Formation|Extent|Crops out in a small area west of the Whittington Range, immediately west of the prominent north-south ridge formed by the Short Range Sandstone.|16-MAY-23
25768|Attack Creek Formation|Thickness range|Within the Tennant Creek Sheet area the formation is at least 800 m thick.|16-MAY-23
25768|Attack Creek Formation|Lithology|A basal calcareous siltstone overlain by dark grey, partly silicified, flaggy limestone with thin interbeds and shale clasts; the limestone grades into black, calcareous, manganese-rich mudstone and black chert. This is succeeded by feldspathic quartz sandstone and silicified orthoquartzite. The uppermost beds are thick-bedded, cream orthoquartzite with 1 to 2 percent of well-rounded pink orthoquartzite pebbles; they contain voids left by weathered-out shale clasts. The top of the formation is truncated by the present-day erosion surface, and its upper beds have been removed.|16-MAY-23
25768|Attack Creek Formation|Relationships and boundaries|Conformable contact with underlying Short Range Sandstone. The formation is situated in the core of a syncline, its upper part is truncated by the present-day erosion surface.|16-MAY-23
25768|Attack Creek Formation|Age reasons|By assumed correlation of Tomkinson Creek Beds with Hatches Creek Group, late Early Proterozoic to Early Carpentarian.|16-MAY-23
23345|Attutra Metagabbro|Name source|Attutra (now called Marshall) copper deposit (630309mE 7494710mN, GDA94, Zone53) in Jervois Range 1:100 000 mapsheet, Northern Territory.|16-MAY-23
23345|Attutra Metagabbro|Unit history|First defined as Attutra Metagabbro in Shaw et al (1985), used in Freeman et al (1986).|16-MAY-23
23345|Attutra Metagabbro|Geomorphic expression|Low rounded hills (5-20 m high), sinuous strike ridges, and isolated nubbins and tors scattered on plains.|16-MAY-23
23345|Attutra Metagabbro|Type section locality|West of Jervois Mine in Jervois Range 1:100 000 mapsheet at 635248mE 7496321mN, no track access.|16-MAY-23
23345|Attutra Metagabbro|Extent|Primary occurrence is in the Jervois Range 1:100 000 Sheet east of the Jervois Fault and west of the Lucy Creek Fault Zone; also occurs in the vicinity of the Midnight Fault north of Bonya Community.|16-MAY-23
23345|Attutra Metagabbro|General description|Metagabbro, metadolerite: fine- to coarse-grained, aphyric with primary igneous textures locally preserved, rare amygdaloidal textures; undeformed to locally foliated.|16-MAY-23
23345|Attutra Metagabbro|Thickness range|<1m to 1 km width.|16-MAY-23
23345|Attutra Metagabbro|Lithology|A medium- to coarse-grained assemblage of amphibole and plagioclase; amphibole occurs as either granular hornblende or as secondary fibrous uralite after pyroxene, and is locally chlorite altered. Plagioclase generally occurs as laths, and less commonly as fine-grained granoblastic aggregates with minor interstitial quartz. Accessory fine-grained magnetite.|16-MAY-23
23345|Attutra Metagabbro|Depositional environment|Continental margin environment, either arc cordillera or back-arc basin.|16-MAY-23
23345|Attutra Metagabbro|Relationships and boundaries|Intrudes Bonya Metamorphics; intruded by unnamed tonalite and Unca Granite; unconformably overlain by Oorabra Arkose and Elyuah Formation.|16-MAY-23
23345|Attutra Metagabbro|Structure and Metamorphism|Weak to moderate grain shape foliation.|16-MAY-23
23345|Attutra Metagabbro|Age reasons|Magmatic crystallisation age of 1786.4 ± 4.2 Ma (SHRIMP 207Pb/206Pb, Claoué-Long and Hoatson 2005).|16-MAY-23
23345|Attutra Metagabbro|Correlations|Interpreted to be co-magmatic and co-genetic with constituent units of the Casper Suite based on similar geochemical and isotopic composition, and timing of structural overprint.|16-MAY-23
23345|Attutra Metagabbro|Alteration and Mineralisation|Minor sericitisation, epidotisation, chloritisation; locally metasomatised; interpreted to be one of the main Cu-sources of scattered occurrences in the adjacent Bonya Metamorphics. Isolated occurrences of massive vanadiferous magnetite.|16-MAY-23
23345|Attutra Metagabbro|Geophysical Expression|Anomalous magnetic low signal; within area of gravity high signal; radiometric low signal; magnetics reveal kilometre-scale, south- to southwest-trending isoclinal folding.|16-MAY-23
23345|Attutra Metagabbro|Geochemistry|Basalt/gabbro; calc-alkaline or tholeiitic compositions; quartz-hypersthene normative; low-Ti, low-K; generally flat REE patterns with rare LREE enrichment; negligible Eu anomalies.|16-MAY-23
23345|Attutra Metagabbro|Defn author|Anett Weisheit, Barry Reno, Eloise Beyer (Northern Territory Geological Survey) 11-OCT-2018.|16-MAY-23
23345|Attutra Metagabbro|Proposed publication|Weisheit A, Reno BL and Beyer EE, in review. Jervois Range Special, Northern Territory. 1:100 000 geological map explanatory notes, 6152 and part 6252. Northern Territory Geological Survey, Darwin.|16-MAY-23
23345|Attutra Metagabbro|References|Freeman MJ, Black LA, Offe LA, Senior BR, Shaw RD, Shergold JH, Simpson CJ, Walter MR, Warren RG, Donnellan N, Horsfall CJ, Laurie JR and Walley AM, 1986. Huckitta, Northern Territory (Second Edition). 1:250 000 geological map series, SF 53-11. Northern Territory Geological Survey, Darwin.  **Shaw RD, Warren RG and Freemann MJ, 1985. Stratigraphic definitions of named units in the Arunta Block, Northern Territory, 1979-82. Bureau of Mineral Resources, Australia, Report 260.  **Claoué-Long JC and Hoatson DM, 2005. Proterozoic mafic-ultramafic intrusions in the Arunta Region, central Australia. Part 2: event chronology and regional correlations. Precambrian Research 142, 134-158.|16-MAY-23
26360|Badalngarrmirri Formation|Name source|From Badalngarrmirri Creek, which drains an area west of the Mitchell Ranges in the eastern Mirrngadja 1:100 000 sheet area.|16-MAY-23
26360|Badalngarrmirri Formation|Geomorphic expression|Due to the alternating quartz arenite/mudstone-siltstone stratigraphy, the formation forms a distinctive set of alternating ridges and valleys, each about 100 m to over 1 km across. Collectively, these ridges and valleys extend over 60 km, and form much of the arcuate Parsons Range.|16-MAY-23
26360|Badalngarrmirri Formation|Type section locality|In the eastern Parsons Range, a composite section made up of three parts. This replaces the reference area nominated by Plumb & Roberts (1992) (along long. 135o30'E). The lowest part, from the top of the Mattamurta Sandstone at lat. 13o15'51"S, long. 135o31'44"E, extends to the top of informal member 4 (see Comments), at lat. 13o16'52"S, long. 135o32'4"E. The middle part of the section extends from 13o17'2"S, long. 135o29'51"E (base of informal member 5) to 13o18'43"S, long. 135o29'45"E (top of Fairy Glen Sandstone Member). The upper portion of the type section runs from 13o18'37"S, long. 135o30'25"E (base of informal member 11) through to the top of the formation at 13o19'29"S, long. 135o30'32"E.|16-MAY-23
26360|Badalngarrmirri Formation|Extent|Main outcrops are in the Parsons Range and southern Mitchell Ranges in the Blue Mud Bay 1:250 000 sheet area, covering around 900 km2. Other outcrops  (1) lie west of the Mitchell Ranges (the Gali Belt, covering around 300 km2), and (2) form a narrow outcrop belt about 1 km wide, along the eastern edge of the Mitchell Ranges, both in the Arnhem Bay 1:250 000 sheet area.|16-MAY-23
26360|Badalngarrmirri Formation|Thickness range|2850 m in the composite type section, thinning to the west and southwest, to about 2200 m and to 1900 m, 40 km and 60 km to the southwest, respectively.|16-MAY-23
26360|Badalngarrmirri Formation|Lithology|Interbedded medium-grained quartz arenite, ferruginous arenite (presumed to have been glauconitic and pyritic, now mostly weathered to iron oxides), laminated green to grey and black mudstone, wavily laminated and hummocky cross-stratified siltstone and very fine-grained sandstone, and minor stromatolitic dolostone and chert.|16-MAY-23
26360|Badalngarrmirri Formation|Depositional environment|Storm-dominated marine shelf, ranging from basinal (below storm-wave base), through lower to upper shoreface and shoreline environments.|16-MAY-23
26360|Badalngarrmirri Formation|Relationships and boundaries|Base placed at a prominent photogeological boundary marking the change from strongly cross-bedded quartz arenite of the uppermost Matttamurta Sandstone to olive green mudstone of the Fawcett Member of the Badalngarrmirri Formation. Plumb & Roberts (1992) included an interval of 90 m of ferruginous sandstone in the Badalngarrmirri Formation in the type area, but this has been included in the Mattamurta Sandstone for three reasons: 1. It does not appear to be a laterally continuous unit, but rather due to local secondary iron precipitation; 2. it is indistinguishable from Mattamurta Sandstone in most outcrops; and 3. the main lithological change is above this sandstone - between it and the overlying mudstone and chert. The Mattamurta Sandstone-Badalngarrmirri Formation contact may be an unconformity, at least locally, as at one locality stromatolitic chert encrusts apparently lithified sandstone, and infills cracks up to 0.5 m deep. The upper contact, with the Marura Siltstone, is conformable, and is placed at the abrupt change from quartz arenite (top of informal member 13) to mudstone; a stromatolitic chert is commonly present a few metres above the contact, within the Marura Siltstone.|16-MAY-23
26360|Badalngarrmirri Formation|Age reasons|Palaeoproterozoic: maximum age is well constrained by the age of the uppermost formation of the Donydji Group, the Fagan Volcanics, at 1710 Ma (Pietsch & others, 1994); minimum age is less well constrained, but must be greater than 1620 Ma, the age of the Yarrawirrie Formation in the overlying Balma Group (Pietsch and others, 1994), and is most likely older than 1640 Ma, the age of the Barney Creek Formation (Page & Sweet, in press), a correlative of the central Balma Group below the Yarrawirrie Formation (Haines, 1994).|16-MAY-23
26360|Badalngarrmirri Formation|Correlations|No known correlatives, although the Surprise Creek Formation in the Mount Isa Inlier (Derrick and others, 1980) is very similar in its lithology, and stratigraphic and tectonic setting.|16-MAY-23
26360|Badalngarrmirri Formation|Proposed publication|Blue Mud Bay Explanatory Notes (Haines and others, 1997).|16-MAY-23
26360|Badalngarrmirri Formation|Comments|The Badalngarrmirri Formation has been subdivided into 14 units, reflecting the alternating sandstone-mudstone lithologies. Three of these, the Fawcett Member, Gali Member, and Fairy Glen Sandstone Member, have been formally defined and delineated on the Blue Mud Bay 1:250 000 sheet, whereas the others, which are easily mappable at photoscale (1:50 000) but not easily represented on 1:250 000 maps, are described only in the accompanying publication (Haines and others, 1997).|16-MAY-23
26360|Badalngarrmirri Formation|References|DERRICK, G.M., WILSON, I.H., & SWEET, I.P., 1980 - The Quilalar and Surprise Creek Formations - new Proterozoic units from the Mount Isa Inlier: their regional sedimentology and application to regional correlations. BMR Journal of Australian Geology & Geophysics, 5, 215-223. **HAINES, P.W., 1994 - The Balma and Habgood Groups, Northern McArthur Basin, Northern Territory: stratigraphy and correlations with the McArthur Group. In HALLENSTEIN, C.P. (Editor), 1994 - AusIMM Annual Conference: `Australian Mining looks north - the challenges and choices'. Australasian Institute of Mining and Metallurgy, Melbourne, 135-138. **HAINES, P.W., RAWLINGS, D.J., SWEET, I.P., PIETSCH, B.A., PLUMB, K.A., MADIGAN, T.L., & KRASSAY, A.A., 1997 - Blue Mud Bay, 1:250 000 geological series. Northern Territory Geological Survey, Explanatory Notes, SD53 7.**PAGE, R.W., & SWEET, I.P., (in press) - Geochronology of basin phases in the western Mount Isa Inlier, and correlation with McArthur Basin. Australian Journal of Earth Sciences. **PIETSCH, B.A., PLUMB, K.A., PAGE, R.W., HAINES, P.W., RAWLINGS, D.J., & SWEET, I.P., 1994 - A revised stratigraphic framework for the McArthur Basin, N.T. In HALLENSTEIN, C.P. (Editor), 1994 - AusIMM Annual Conference: `Australian Mining looks north - the challenges and choices'. Australasian Institute of Mining and Metallurgy, Melbourne, 135-138. **PLUMB, K.A., & ROBERTS, H.G., 1992 - The geology of Arnhem Land, Northern Territory. Bureau of Mineral Resources, Australia, Record, 1992/55, 193pp.|16-MAY-23
80342|Baikal Supersuite|Name source|After Baikal Aboriginal Community (619100 mE 7479900 mN, GDA94, Zone53) in Jervois Range 1:100 000 mapsheet, Northern Territory.|16-MAY-23
80342|Baikal Supersuite|Constituents|Casper Suite: White Violet Orthogneiss, Attutra Metagabbro, Kings Legend Metadolerite, Xanten Granodiorite, unnamed granodiorite, Cappocks Granodiorite, Jervois Granodiorite; Mascotte Orthogneiss; Fosters Suite: Jericho Granite, Thring Granite, Unca Granite.|16-MAY-23
80342|Baikal Supersuite|Geomorphic expression|Generally poorly exposed; scattered outcrops; low, blocky or rounded outcrops; jointed pavements; sharp crested and bouldery hills, ridges, tors; sills and minor dykes.|16-MAY-23
80342|Baikal Supersuite|Type section locality|There is no single locality where all constituent units are exposed. See definition cards for description of constituent suites and individual units.|16-MAY-23
80342|Baikal Supersuite|Extent|Constituent units sporadically outcrop in the western and central area of the Jervois Range 1:100 000 mapsheet, north of the Marshall River and south and southeast of the Johannsen and Jervois ranges (between 7473000mN-7503000mN and 595000mE-657000mE, GDA94, Zone 53).|16-MAY-23
80342|Baikal Supersuite|General description|Constituent units vary in composition: metagabbro, metadolerite, granodiorite, granite with subordinate tonalite, diorite, quartz diorite, monzodiorite and quartz monzodiorite. All constituent units are deformed by a regional main foliation. Local concordant intrusive relationships with Bonya Metamorphics, locally contains xenoliths of Bonya Metamorphics; locally exposed intrusive relationships between the constituent units; intruded by Tarlton Granite, Boundary Igneous Complex and Samarkand Pegmatite; locally unconformably overlain by Oorabra Arkose and Grant Bluff Formation of the Georgina Basin; locally faulted contacts with various units of the Georgina Basin.|16-MAY-23
80342|Baikal Supersuite|Depositional environment|Continental margin environment, either arc cordillera or back arc basin, or derived from melting of pre-existing crust that formed in a continental margin environment.|16-MAY-23
80342|Baikal Supersuite|Structure and Metamorphism|All constituent units are overprinted by the regional main foliation ranging from weakly to strongly foliated (grain shape foliation) and gneissic, mafic rocks locally undeformed; locally overprinted by mylonitic foliation along and adjacent to fault zones; all constituent units deformed during regional high-thermal gradient amphibolite facies metamorphism but metamorphic overprint is not always apparent.|16-MAY-23
80342|Baikal Supersuite|Age reasons|Crystallisation ages of constituent units vary between ca 1.79-1.77 Ga (LA-ICP-MS zircon U-Pb, Beyer et al 2018, Beyer et al in prep; SHRIMP 207Pb/206Pb, Zhao and Bennett 1995, Claoué-Long and Hoatson 2005, Cross et al 2005, Kositcin et al 2011, 2014, 2018); all constituent units are deformed by a regional deformation event that occurred at ca 1.76 Ga (LA-ICP-MS U-Pb monazite, Reno et al 2016).|16-MAY-23
80342|Baikal Supersuite|Correlations|No known correlatives.|16-MAY-23
80342|Baikal Supersuite|Alteration and Mineralisation|Local K-feldspar-quartz alteration, hematitisation, silicification and brecciation, quartz and calcite veining is common close to shear zones; sporadic copper and iron-titanium-vanadium mineralisation in mafic units.|16-MAY-23
80342|Baikal Supersuite|Geophysical Expression|When extensive enough the constituent felsic units are characterised by magnetic-low signals, often with a magnetic-high contact aureole; the constituent mafic units have a magnetic anomalously low signal; no clear gravity signal; felsic units are characterised by a radiometric high signal, mafic units show a radiometric low signal.|16-MAY-23
80342|Baikal Supersuite|Geochemistry|I-type intrusives; dominantly peraluminous and less commonly metaluminous compositions, calc-alkaline to shoshonitic compositions, enriched in LREE compared to HREE, negative Eu anomalies variably developed, juvenile to evolved Nd isotopic signatures.|16-MAY-23
80342|Baikal Supersuite|Defn author|Anett Weisheit, Barry Reno, Eloise Beyer (Northern Territory Geological Survey) 01-MAY-2018.|16-MAY-23
80342|Baikal Supersuite|Proposed publication|Weisheit A, Reno BL and Beyer EE, in review. Jervois Range Special, Northern Territory. 1:100 000 geological map explanatory notes, 6152 and part 6252. Northern Territory Geological Survey, Darwin.|16-MAY-23
80342|Baikal Supersuite|References|Beyer EE, Reno BL, Weisheit A, Whelan JA, Thompson JM, Meffre S and Woodhead JD, 2018. Summary of results. NTGS laser ablation ICP-MS U-Pb-Hf geochronology project: selected samples from JERVOIS RANGE 1:100 000 and TOBERMOREY 1:250 000 mapsheets, Aileron and Irindina provinces, January 2014 - December 2016. Northern Territory Geological Survey, Record 2018-001. **Beyer EE, Reno BL, Weisheit A, Meffre S, Thompson J and Woodhead JD, in prep. Summary of results. NTGS laser ablation ICP-MS U-Pb-Hf geochronology project: selected samples from Jinka and Jervois Range 1:100 000 mapsheets, Aileron and Irindina Provinces, Arunta Region, January 2016 - December 2017. Northern Territory Geological Survey, Darwin.  **Claoué-Long JC and Hoatson DM, 2005. Proterozoic mafic-ultramafic intrusions in the Arunta Region, central Australia. Part 2: event chronology and regional correlations. Precambrian Research 142, 134 -158.  **Cross A, Claoué-Long JC, Scrimgeour IR, Ahmad M and Kruse PD 2005. Summary of results. Joint NTGS-GA geochronology project: Rum Jungle, basement to the Georgina Basin and eastern Arunta Region 2001-2003. Northern Territory Geological Survey Record 2005-006.  **Kositcin N, Magee CW, Whelan JA and Champion DC, 2011. New SHRIMP geochronology from the Arunta Region: 2009-2010. Geoscience Australia, Record 2011/14.  **Kositcin N, Beyer EE and Whelan JA, 2014. Summary of results. Joint NTGS¿GA SHRIMP geochronology project: Arunta Region, July 2013-June 2014. Northern Territory Geological Survey, Record 2014-008.  **Kositcin N, Reno BL and Beyer EE, 2018. Summary of results. Joint NTGS¿GA geochronology project: Aileron Province, July 2015-June 2016. Northern Territory Geological Survey, Record 2018-005.  **Reno BL, Whelan JA, Weisheit A, Kraus S, Beyer EE, Meffre S and Thompson J, 2016. Summary of Results. NTGS laser ablation ICP-MS in situ monazite geochronology project: Arunta Region, July 2013-June 2014. Northern Territory Geological Survey, Record.  **Zhao JX and Bennett VC, 1995. SHRIMP U-Pb zircon geochronology of granites in the Arunta Inlier, central Australia: implications for Proterozoic crustal evolution. Precambrian Research 71, 17-43.|16-MAY-23
21185|Balma Group|Name source|Balma Community on the Blue Mud Bay 1:250 000 scale map area (latitude 13o14'S, longitude 135o51'E).|16-MAY-23
21185|Balma Group|Unit history|Formally mapped as McArthur Group by Plumb and Roberts (1965). However, it has no formations in common with the McArthur Group of the southern McArthur Basin (which has priority of usage) and although interpreted to correlate, at least in part, with the McArthur Group, the precise nature of such correlations is speculative. Correlations with the Habgood Group to the north are easier than those with the McArthur Group. This inconsistency is alleviated by establishing a new group.|16-MAY-23
21185|Balma Group|Constituents|In ascending order: Koolatong Siltstone, Strawbridge Breccia, Vaughton Siltstone, Conway Formation, Zamia Creek Siltstone, Yarrawirrie Formation, Baiguridji Formation and Bath Range Formation. These units were named by Plumb and Roberts (1965) and defined by Plumb and Roberts (1992).|16-MAY-23
21185|Balma Group|Geomorphic expression|Resistant units crop out as low strike ridges. Other units crop out sparsely as low rubbly rises and in creek bank exposures.|16-MAY-23
21185|Balma Group|Type section locality|Type sections as for each constituent formation (see Plumb and Roberts, 1992).|16-MAY-23
21185|Balma Group|Extent|Largely restricted to the Blue Mud Bay 1:250 000 map sheet area in Arnhem Land, Northern Territory. Minor outcrops occur near the southern edge of the Arnhem Bay 1:250 000 map sheet area.|16-MAY-23
21185|Balma Group|Thickness range|Estimated composite thickness of about 4500 m.|16-MAY-23
21185|Balma Group|Lithology|Shallow water dolostone, mudstone and sandstone. Minor tuffaceous rocks and limestone.|16-MAY-23
21185|Balma Group|Relationships and boundaries|Conformably overlies the Fleming Sandstone of the Parsons Range Group. Overlain by the Balbirini Dolomite of the Nathan Group, but the contact relationship could not be determined due to poor outcrop. Locally intruded by dykes, largely on geophysical evidence.|16-MAY-23
21185|Balma Group|Structure and Metamorphism|Most areas (except near major faults) are gently folded with low dip angles. Faulting is common.|16-MAY-23
21185|Balma Group|Age reasons|Tuffaceous rocks from the Yarrawirrie Formation and basal Bath Range Formation have given SHRIMP U-Pb zircon ages of 1620+/-21 Ma and 1599+/-11 Ma respectively (Pietsch et al., 1994). These provide maximum ages for the time of sedimentation.|16-MAY-23
21185|Balma Group|Correlations|The McArthur Group to the south and the Habgood Group to the north.|16-MAY-23
21185|Balma Group|Proposed publication|Proceedings The AusIMM Annual Conference (Haines, 1994, in press)|16-MAY-23
32954|Barkly Group|Name source|From Barkly Tableland of central-eastern Northern Territory and adjacent western Queensland.|16-MAY-23
32954|Barkly Group|Unit history|Templeton Series and Georgina Series of Whitehouse (1936) in part.|16-MAY-23
32954|Barkly Group|Constituents|Top Springs Limestone, Gum Ridge Formation, Anthony Lagoon beds, Wonarah Formation, Ranken Limestone, Camooweal Dolostone.|16-MAY-23
32954|Barkly Group|Geomorphic expression|Generally not exposed or poorly outcropping; prominent hills in Lake Nash Anticline (southern AVON DOWNS); well exposed in incised drainage of Gregory River system (eastern RANKEN-western CAMOOWEAL); low hills astride Barkly Highway at FREW RIVER-ALROY-AVON DOWNS-RANKEN junction; low hills and rises on eastern flank of Tennant Region (TENNANT CREEK-HELEN SPRINGS); locally well exposed in dissected and plains country in northern WALLHALLOW-southern BAUHINIA DOWNS.|16-MAY-23
32954|Barkly Group|Extent|Central, western and northern Georgina Basin in western URANDANGI, western MOUNT ISA, western CAMOOWEAL, southwestern LAWN HILL, AVON DOWNS, RANKEN, MOUNT DRUMMOND, FREW RIVER, ALROY, BRUNETTE DOWNS, WALLHALLOW, southern BAUHINIA DOWNS, northeastern BONNEY WELL, eastern TENNANT CREEK, HELEN SPRINGS; subsurface in BEETALOO, TANUMBIRINI, HODGSON DOWNS.|16-MAY-23
32954|Barkly Group|Thickness range|Drillhole thicknesses: 201 m in NTGS96/1 (HELEN SPRINGS), 385 m in BN04DD01 (western BRUNETTE DOWNS), 334 m in NTGS02/1 and 320 m in Brunette Downs 1 (central BRUNETTE DOWNS), 312+ m in Frewena 1 (western ALROY), 141 m in BMR Alroy 2 (eastern ALROY), 185 m in NTGS00/1 (western RANKEN), 441 m in NTGS01/1 (eastern RANKEN), 430 m in BMR Cattle Creek 1 (northern AVON DOWNS), 353 m in Lake Nash 1 (southern AVON DOWNS) (Bastian and Thieme 1970, Questa 1994, Hussey et al 2001, Kruse 2003).|16-MAY-23
32954|Barkly Group|Lithology|Limestone, dolostone, siltstone, minor quartz sandstone.|16-MAY-23
32954|Barkly Group|Depositional environment|Peritidal to marine.|16-MAY-23
32954|Barkly Group|Relationships and boundaries|Unconformably overlies early Middle Cambrian Thorntonia Limestone (Narpa Group) in Undilla Sub-basin. Unconformably overlies Early Cambrian Helen Springs Volcanics and correlative Peaker Piker Volcanics or where these are absent, Mesoproterozoic Renner Group and correlative South Nicholson Group. Passes laterally into Narpa Group of southern and eastern Georgina Basin. Conformably overlain by Upper Cambrian Arrinthrunga Formation (Narpa Group), or where this is absent, unconformably overlain by Mesozoic rocks.|16-MAY-23
32954|Barkly Group|Age reasons|Middle Cambrian: commences in Ordian-early Templetonian, based on fossiliferous Gum Ridge Formation (Öpik in Ivanac 1954, Kruse 1998) and Top Springs Limestone (Smith 1964, Plumb and Rhodes 1964, Kruse 1991); continues to putative latest Middle Cambrian based on conformable passage into overlying, notionally Upper Cambrian Arrinthrunga Formation.|16-MAY-23
32954|Barkly Group|Correlations|Narpa Group of southern and eastern Georgina Basin in part; lower Goulburn Group of Arafura Basin; Daly River Group of Daly Basin in part; Montejinni Limestone, Hooker Creek Formation, Lothari Hill Sandstone and Point Wakefield beds of Wiso Basin; Goose Hole Group of Ord Basin; Tarrara Formation and Hart Spring Sandstone of Bonaparte Basin; Pertaoorrta Group of Amadeus Basin in part.|16-MAY-23
32954|Barkly Group|Comments|The group encompasses all Middle Cambrian sedimentary rocks in the central, western and northern Georgina Basin, exclusive of the Thorntonia Limestone (Narpa Group). The group name is here reinstated, having been abandoned by Smith (1972: 11). The present group concept largely coincides in area with the original concept of Noakes and Traves (1954: 37-38), but excludes the Narpa Group of Dunster et al (in prep).|16-MAY-23
27283|Barrow Creek Granite Complex|Name source|Barrow Creek and the Barrow Creek township on the Barrow 1:100 000 Sheet (5654).|16-MAY-23
27283|Barrow Creek Granite Complex|Unit history|Previously called the Barrow Creek Granite (Smith and Milligan, 1964), but not recognised as three separate phaseas of intrusion.|16-MAY-23
27283|Barrow Creek Granite Complex|Constituents|Ooralingie Granite: Type locality at AMG GR LS862204 (latitude 21o30'58"S, longitude 133o53'55"E). Bean Tree Granite: Type locality at AMG GR LS864195 (latitude 21o31'24"S, longitude 133o54'06"E). Unnamed pegmatite: medium to very coarse, with tourmaline, muscovite, quartz with undulose extinction, partly sericitised plagioclase (now albite), alkali feldspar (microcline and orthoclase common) and traces of sphene. |16-MAY-23
27283|Barrow Creek Granite Complex|Type section locality|Reference locality at AMG GR LS893080 where the relationships between the intrusive phases are seen. Here the Ooralingie Granite occurs as a large xenolith in the Bean Tree Granite and the Bean Tree Granite is intruded by pegmatite.|16-MAY-23
27283|Barrow Creek Granite Complex|Extent|Southeast corner of Crawford (5655), northwest corner of Home of Bullion (5754) and northeast corner of Barrow 1:100 000 sheets.|16-MAY-23
27283|Barrow Creek Granite Complex|Relationships and boundaries|Intrudes the Bullion Schist and is unconformably overlain by late Proterozoic sediments. The Ooralingie Granite is oldest constituent, being intruded by the Bean Tree Granite following foliation. Both are intruded by unnamed pegmatite.|16-MAY-23
27283|Barrow Creek Granite Complex|Age reasons|May range in age from Early to Middle Proterozoic.|16-MAY-23
27283|Barrow Creek Granite Complex|Comments|Mention as Barrow Creek Granite Fig. 8.|16-MAY-23
27283|Barrow Creek Granite Complex|References|01/31592|16-MAY-23
21201|Bartalumba Basalt|Name source|Bartalumba Bay on the northern side of Groote Eylandt, BLUE MUD BAY.|16-MAY-23
21201|Bartalumba Basalt|Unit history|Where previously differentiatedit was mapped as the now abandoned 'Bickerton Volcanics' (Groote Eylandt) or as unnamed dolerite (Bickerton Island) by Plumb and Roberts (1965, 1992).|16-MAY-23
21201|Bartalumba Basalt|Geomorphic expression|Very recessive. Top of unit crops out locally where protected by overlying scarps of Dalumbu Sandstone.|16-MAY-23
21201|Bartalumba Basalt|Type section locality|Upper boundary stratotype: Bluff Hill area (lat. 13o 59'S, long 136o 44'E; GR PE877535); 20m of rubbly section contigous with contact.|16-MAY-23
21201|Bartalumba Basalt|Extent|Scattered small outcrops acorss northern Groote Eylandt. One small outcrop on eastern coast of Bickerton Island (PORT LANGDON and BLUE MUD BAY).|16-MAY-23
21201|Bartalumba Basalt|Thickness range|Cannot be accurately determined as base is not exposed, but a thickness in the order of 200-500m can be inferred for the northern Groote Eylandt. Probably thins to the west towards Bickerton Island.|16-MAY-23
21201|Bartalumba Basalt|Lithology|Amyglodial basalt.|16-MAY-23
21201|Bartalumba Basalt|Depositional environment|Subaerial flows.|16-MAY-23
21201|Bartalumba Basalt|Relationships and boundaries|Part of the Alyangula Subgroup of the Groote Eylandt Group. Inferred to overlie Alyinga Sandstone. Overlain with structural concordance by Dalumbu Sandstone, but contact is not exposed.|16-MAY-23
21201|Bartalumba Basalt|Age reasons|Probably Statherian (Palaeoproterozoic). The Bickerton Rhyolite in the underlying Bustard Subgroup has been dated by SHRIMP single-zircon U-Pb techniques at ~1815Ma (Pietsch et al. 1994).|16-MAY-23
21201|Bartalumba Basalt|Correlations|May correlate with the Seigal Volcanics of the Tawallah Group.|16-MAY-23
24175|Bean Tree Granite|Name source|Bean Tree Waterhole (AMG GR LS938003) on the Barrow 1:100 000 sheet (5654).|16-MAY-23
24175|Bean Tree Granite|Unit history|Previously included in the 'Barrow Creek Granite' (Smith and Milligan, 1964).|16-MAY-23
24175|Bean Tree Granite|Geomorphic expression|Low, irregular hills and tors, isolated and rubbly outcrops; best but very weathered exposures near overlying late Proterozoic sedimentary rocks; light air photo tones.|16-MAY-23
24175|Bean Tree Granite|Type section locality|South of the Barrow Creek Racecourse on the Barrow 1:100 0000 sheet at AMG GR LS864195 (latitude 21o31'24"S, longitude 133o54'06"E).|16-MAY-23
24175|Bean Tree Granite|Extent|Southeast corner of Crawford (5655) and northeast corner of Barrow 1:100 000 sheets.|16-MAY-23
24175|Bean Tree Granite|Lithology|Granite: fine to medium, leucocratic, porphyritic to even-grained, with biotite, muscovite, quartz (with undulose extinction), partly sericitised plagioclase, alkali feldspar (microcline common +/- perthite), traces of chlorite, zircon and apatite; common alkali feldspar oikocrysts with quartz and partly sericitised plagioclase chadacrysts; granular anhedral texture.|16-MAY-23
24175|Bean Tree Granite|Relationships and boundaries|Included in the Barrow Creek Granite Complex. Intrudes Ooralingie Granite (e.g. at AMG GR LS893080 where the Ooralingie Granite occurs as a large xenolith in the Bean Tree Granite) and the Bullion Schist (e.g. at AMG GR LS824006). Intruded by pegmatite (Pgbc).|16-MAY-23
24175|Bean Tree Granite|Structure and Metamorphism|Faulted in places.|16-MAY-23
24175|Bean Tree Granite|Age reasons|Has been dated by Hurley and others (1961) as 1460 Ma by the K-Ar method and as 1550 Ma by the Rb-Sr method, but this is considered inaccurate and possibly only a minimum age. May be contemporaneous with the Elkedra Granite, which intrudes the Hatches Creek Group and has been dated by the Rb-Sr whole rock method at about 1660 Ma (Blake and others, 1987).|16-MAY-23
83009|Beef Hole Gabbro|Name source|Beef Hole Gabbro is named after Beef Hole (GDA94, 53K, 648776nE, 7814713mN), which lies approximately 40 km to the east of the type intersection of this unit.|16-MAY-23
83009|Beef Hole Gabbro|Unit history|Collings (2009) referred to this unit as `layered norite-gabbro?. Referred to as `microdiorite? by Cross et al. (2020), who published a U?Pb SHRIMP age for the unit (see below).|16-MAY-23
83009|Beef Hole Gabbro|Geomorphic expression|No known outcrops.|16-MAY-23
83009|Beef Hole Gabbro|Type section locality|Drillhole DDH004, down-hole depth from 157.53 m to 252.20 m (EOH). Drillhole location 609375mE 7816424mN (MGA94 zone 53)/ 19.757654S 136.419988E. Drill core is stored at the NTGS core library in Alice Springs.|16-MAY-23
83009|Beef Hole Gabbro|Description at type locality|Light grey and black, medium-grained, mafic intrusive rock. Locally weakly foliated.|16-MAY-23
83009|Beef Hole Gabbro|Extent|This unit can be mapped in regional geophysical data as a magnetic high. It extends only several kilometres away from drillhole DDH004 (Clark et al., 2021).|16-MAY-23
83009|Beef Hole Gabbro|General description|Only known in the type interval. See description above.|16-MAY-23
83009|Beef Hole Gabbro|Thickness range|Approximately 100 m of this intrusive unit is intersected in drill core. The bottom of the unit was not intersected.|16-MAY-23
83009|Beef Hole Gabbro|Lithology|Light grey and black medium-grained, mafic intrusive rock. Plagioclase and amphibole comprise most of the rock, with minor quartz and biotite present in some samples.|16-MAY-23
83009|Beef Hole Gabbro|Depositional environment|Genesis: Although the Beef Hole Gabbro shares some similarities with arc-related rocks, the lack of a negative Ti anomaly and evolved Nd isotope signature suggests the trace element patterns may instead result from assimilation of crustal material.|16-MAY-23
83009|Beef Hole Gabbro|Relationships and boundaries|Kalkarindji Suite basalt nonconformably overlies this unit.|16-MAY-23
83009|Beef Hole Gabbro|Identifying features|Dark colour, mafic composition, medium grain size. Very high magnetic susceptibility in places. The age of this unit (ca. 1850 Ma) is a characteristic feature.|16-MAY-23
83009|Beef Hole Gabbro|Structure and Metamorphism|In drill core, this unit presents as relatively massive. However, a weak foliation is present locally, along with brittle veining. In regional magnetics imagery, the local magnetic high that characterises the unit is wrapped by anastomosing lineaments that break the magnetic high into multiple slivers. It is likely, therefore, that this unit predates significant regional deformation.|16-MAY-23
83009|Beef Hole Gabbro|Age reasons|Cross et al. (2020) determined a SHRIMP U?Pb emplacement age for this unit of 1849.2 +/- 2.9 Ma.|16-MAY-23
83009|Beef Hole Gabbro|Alteration and Mineralisation|Unknown.|16-MAY-23
83009|Beef Hole Gabbro|Geophysical Expression|Down-hole geophysical data is not available for this unit. However, regional geophysical imagery indicate that the magnetic susceptibly and density of this unit are significantly higher than the immediately adjacent basement rocks of the Alroy Formation.|16-MAY-23
83009|Beef Hole Gabbro|Geochemistry|Two samples of Beef Hole Gabbro have SiO2 ranging 43.6?48.7 wt.%, MgO 7.05?7.87 wt.% and Mg# 29?41. N-MORB-normalised trace elements show enrichment in large ion lithophile elements, a negative Nb-Ta anomaly, and concentrations of medium to heavy rare earth elements and high field strength elements (except Th and Pb) below N-MORB concentrations.  A single whole rock Nd isotope analysis has evolved Nd isotopic composition (epsilonNd 1849 Ma = -3.09).|16-MAY-23
83009|Beef Hole Gabbro|Defn author|A.D. Clark 24-MAR-2022.|16-MAY-23
83009|Beef Hole Gabbro|Proposed publication|Schofield and Clark et al., (in prep). Geology of the East Tennant area, Northern Territory, journal publication.|16-MAY-23
83009|Beef Hole Gabbro|References|Collings, P.S., 2009. Relinquishment report for EL 23726, for the period 1 August 2003 to 31 July 2009, 801 Project. Open File Company Report, CR2009-0749. https://geoscience.nt.gov.au/gemis/ntgsjspui/handle/1/75417  **Clark, A., Highet, L., Schofield, A., Doublier, M., 2021. Solid Geology map of the East Tennant region, dataset, Geoscience Australia.  **Cross, A.J., Clark, A.D., Schofield, A., Kositcin, N., 2020. New SHRIMP U-Pb zircon and monazite geochronology of the East Tennant region: a possible undercover extension of the Warramunga Province, Tennant Creek. In: Czarnota, K., Roach, I., Abbott, S., Haynes, M., Kositcin, N., Ray, A., Slatter, E. (Eds.), Exploring for the Future: Extended Abstracts, Geoscience Australia, Canberra, 1?4. http://dx.doi.org/10.11636/132771|16-MAY-23
41843|Belt Granite|Name source|Belt Range 23o21'00" S, 131?53'00" E, MOUNT LIEBIG|16-MAY-23
41843|Belt Granite|Unit history|Previously included within undifferentiated gneiss, schist, amphibolite, quartzite, granite, dolerite and pegmatite of the Arunta Complex  (Ranford 1969)|16-MAY-23
41843|Belt Granite|Geomorphic expression|Low rubbly hills and rises, with extensive areas of shallow subcrop and less common prominent rocky hills.|16-MAY-23
41843|Belt Granite|Type section locality|Outcrops 6 km south-southeast of Alkipi outstation at 23o18'57.95"S, 131o47'52.13"E (WGS 84), MOUNT LIEBIG.|16-MAY-23
41843|Belt Granite|Description at type locality|Foliated, weakly porphyritic biotite-hornblende granite. Rare hornblende-bearing leucosomes|16-MAY-23
41843|Belt Granite|Extent|East-trending zone north and northwest of Belt Range, from the headwaters of Yaya Creek in the west to the headwaters of Beantree Creek in the east, and  outcrops 5-8 km north of Mount William, eastern MOUNT LIEBIG.|16-MAY-23
41843|Belt Granite|Lithology|Foliated, weakly porphyritic biotite and biotite-hornblende granite and granodiorite. The mineralogy of the rock comprises biotite, K-feldspar, plagioclase and quartz with less abundant hornblende, ilmenite and titanite. Phenocrysts of K-feldspar are typically 0.5-1.0 cm in diameter. The biotite granites are intruded by leucogranite and aplite dykes, with locally occurring larger leucogranite bodies. The granite contains a variably developed biotite foliation and south to southwest-plunging stretching lineation, and locally contains minor hornblende-bearing leucosomes.|16-MAY-23
41843|Belt Granite|Relationships and boundaries|Intrudes Alkipi Metamorphics and unnamed felsic gneiss of the Yaya Metamorphic Complex. Intruded by Stuart Pass Dolerite (Warren and Shaw 1995). Thrusted contact with Bitter Springs Formation.|16-MAY-23
41843|Belt Granite|Age reasons|Late Palaeoproterozoic. Intrudes Alkipi Metamorphics, which were deposited in the interval 1660-1640 Ma. Interpreted to have intruded during 1640-1635 Ma Liebig Orogeny, along with other granites in the region.|16-MAY-23
41843|Belt Granite|Correlations|No direct correlatives. The unit is likely to be of a similar age to the Illili and Waluwiya Suites and Papunya Igneous Complex.|16-MAY-23
41843|Belt Granite|Comments|The unit was metamorphosed at upper amphibolite facies conditions during the 1590-1560 Ma Chewings Orogeny.|16-MAY-23
41843|Belt Granite|References|Ranford LC, 1969. Mount Liebig, Northern Territory (First Edition). 1:250 000 geological map series explanatory notes, SF52-16. Bureau of Mineral Resources, Australia. **Scrimgeour IR, Close DF & Edgoose CJ, in prep. Mount Liebig, Northern Territory (Second Edition) 1:250 000 geological map series explanatory notes, SE 52-16. Northern Territory Geological Survey, Darwin. **Warren RG and Shaw RD 1995. Hermannsburg, Northern Territory (Second Edition). 1:250 000 geological map series explanatory notes, SF-53-13. Northern Territory Geological Survey, Darwin.|16-MAY-23
42492|Benmara Group|Name source|Benmara Creek, a tributary of the Nicholson River in the MOUNT DRUMMOND (latitude 18o12'S longitude 137oE).|16-MAY-23
42492|Benmara Group|Unit history|'Benmara beds' of Smith and Roberts (1963).|16-MAY-23
42492|Benmara Group|Constituents|Breakfast Sandstone, Buddycurrawa Volcanics.|16-MAY-23
42492|Benmara Group|Geomorphic expression|Recessive to mildly resistant.|16-MAY-23
42492|Benmara Group|Type section locality|As defined for each constituent formation.|16-MAY-23
42492|Benmara Group|Extent|Northwestern MOUNT DRUMMOND.|16-MAY-23
42492|Benmara Group|Thickness range|0-380 m.|16-MAY-23
42492|Benmara Group|Lithology|Mixed sequence of sandstone, mudstone, conglomerate, stromatolitic chert, trachyte and volcaniclastic sandstone.|16-MAY-23
42492|Benmara Group|Relationships and boundaries|Unconformably overlies Murphy Metamorphics and Connellys Volcanics. The contact with the overlying South Nicholson Group is poorly exposed and the relationship cannot be resolved with any certainty. Pinching out of the Benmara Group to the north near 705000E 8007000N is consistent with both an unconformity and a low-angle structural boundary (detachment) dividing the Benmara and South Nicholson Groups. Rawlings et al (in prep) favour a partly reactivated unconformity.|16-MAY-23
42492|Benmara Group|Age reasons|Constrained only by the underlying Murphy Metamorphics and Connellys Volcanics basement (>1845 Ma; Page et al 2000) and probable overlying South Nicholson Group (maximum age ~1500 Ma by correlation with Roper Group; Jackson et al 1999, Abbott et al 2001). Geochronological studies have failed thus far to establish the absolute age of the Buddycurrawa Volcanics, because the trachyte contains too few zircons and is highly weathered. The simplest interpretation is that the Buddycurrawa Volcanics are the same age as the Carrara Range Group and Peters Creek Volcanics (~1725 Ma), which also contain abundant felsic volcanics and shallow intrusives. However, an age closer to 1660-1580 Ma can be implied from their compositional similarity to magmatic rocks in the Coanjula area (Rawlings et al in prep).|16-MAY-23
42492|Benmara Group|Correlations|Uncertain.|16-MAY-23
42492|Benmara Group|Defn author|Rawlings, D.J. [approved 11-APR-2005]|16-MAY-23
42492|Benmara Group|Comments|This package of rocks has been accorded group status because its stratigraphic position is better established now and it is unlikely to belong to the South Nicholson Group. In addition, two distinct formations have been recognised within what was previously known as the 'Benmara beds', making group status necessary. Note: All locations are based on the GDA94 geodetic datum. Standard series 1:250 000 sheet names are shown in upper case.|16-MAY-23
42492|Benmara Group|References|ABBOTT S.T., Sweet I.P., Plumb K.A., Young D.N., Cutovinos A., Ferenczi P.A., Brakel A. and Pietsch B.A., 2001. Roper region: Urapunga and Roper River special, Northern Territory (Second Edition); 1:250 000 Geological Map Series, sheets SD53-10,11. Northern Territory Geological Survey-Australian Geological Survey Organisation (NGMA), Map and Explanatory Notes.  **JACKSON M.J., Sweet I.P., Page R.W. and Bradshaw B.E., 1999. The South Nicholson and Roper Groups: evidence for the early Proterozoic Roper Superbasin. In: Bradshaw B.E. and Scott D.L. (Eds.), Integrated basin analysis of the Isa Superbasin using seismic, well-log and geopotential data: an evaluation of the economic potential of the northern Lawn Hill Platform. Australian Geological Survey Organisation, Record 1999/19 (unpaginated).  **PAGE R.W., Jackson M.J. and Krassay A.A., 2000. Constraining sequence stratigraphy in north Australian basins: SHRIMP U-Pb zircon geochronology between Mt Isa and McArthur River. Australian Journal of Earth Sciences, 47, 3; 431-459.  **RAWLINGS D.J. Sweet I.P. and Kruse P.D., in prep.[2008] Mount Drummond, Northern Territory (Second Edition); 1:250 000 Geological Map Series, sheet SE53-12. Northern Territory Geological Survey, Map and Explanatory Notes.  **SMITH J.W. and Roberts H.G., 1963. Mount Drummond, N.T. (First Edition); 1:250,000 geological series, sheet SE53-12. Bureau of Mineral Resources, Geology and Geophysics, Map and Explanatory Notes.|16-MAY-23
75949|Benning Gabbro|Name source|After Benning Yard GDA 94 52L, 778200mE 8404300mN (14°25'11"S 131°34'48"E) on Fergusson River 1:250 000 mapsheet, Fergusson River 1:100 000 mapsheet, Litchfield Province, Pine Creek Orogen, Northern Territory|16-MAY-23
75949|Benning Gabbro|Unit history|Previously known as Wangi Basics, first used by Needham and Stuart-Smith (1984) and formally defined in Dundas et al (1987). The name Wangi Basics is abandoned, as it is now known to comprise distinct geochemical groups of rocks which are genetically unrelated.|16-MAY-23
75949|Benning Gabbro|Geomorphic expression|Blocky ridges within surrounding metasedimentary host rocks.|16-MAY-23
75949|Benning Gabbro|Type section locality|Prominent sill (ca 0.6 km length) within Chilling Sandstone, Wingate Mountains 1:100 000 mapsheet (Fergusson River 1:250 000 mapsheet), GDA 94 52L 668414mE 8434455mN ( 14º9'22"S 130°33'37"E).|16-MAY-23
75949|Benning Gabbro|Description at type locality|Occurs as a prominent linear gabbroic sill in Wingate Mountains  1:100 000 mapsheet, length ca 0.6 km within the Chilling Sandstone.|16-MAY-23
75949|Benning Gabbro|Extent|Linear sills over an area of about 6 km long and 200 m wide in Wingate Mountains and Moyle 1:100 000 mapsheets.|16-MAY-23
75949|Benning Gabbro|General description|Occurs as a series of linear sills in Wingate Mountains and Moyle 1:100 000 mapsheets|16-MAY-23
75949|Benning Gabbro|Lithology|Metamorphosed high-Ti tholeiitic gabbro mostly occurring as northeast-trending linear sills  over an area 6 km long and 200 m wide within Burrell Creek Formation and Chilling Sandstone (Edgoose et al 1989). Mostly quartz-hypersthene normative; comprises metamorphosed equigranular assemblages of (rare) quartz, plagioclase with highly sausseritised/sericitised cores and unaltered rims, clinopyroxene, pale brown to green pleochroic hornblende; fibrous actinolite/tremolite and uralitised hornblende common.|16-MAY-23
75949|Benning Gabbro|Depositional environment|Genesis: Intrusive sills into metasedimentary Burrell Creek Formation and Chilling Sandstone.|16-MAY-23
75949|Benning Gabbro|Relationships and boundaries|Intrudes the 1860 Ma Burrell Creek Formation and Chilling Sandstone in Wingate Mountains and Moyle 1:100 000 mapsheets|16-MAY-23
75949|Benning Gabbro|Identifying features|Typically high-Ti tholeiitic gabbros with characteristic alkaline enrichment (Glass 2007, 2010).|16-MAY-23
75949|Benning Gabbro|Structure and Metamorphism|Amphibolite-facies metamorphism; disrupted by south-southwest-trending faults. First Edition mapping (Edgoose et al 1989) shows regional open folding of host successions around south-southwest-plunging axes.|16-MAY-23
75949|Benning Gabbro|Age reasons|Not adequately constrained but <ca 1860 Ma or younger based on field relationships with the metasedimentary Burrell Creek Formation and Chilling Sandstone|16-MAY-23
75949|Benning Gabbro|Correlations|None known|16-MAY-23
75949|Benning Gabbro|Alteration and Mineralisation|Sausseritisation/sericitisation of feldspars; hornblende altered to actinolite/tremolite and uralite; minor chlorite alteration|16-MAY-23
75949|Benning Gabbro|Geophysical Expression|Linear sills have strong positive magnetic response.|16-MAY-23
75949|Benning Gabbro|Geochemistry|High-Ti tholeiitic gabbro  (TiO2 values in range 1.9-4.2 wt%, average 2.3 wt%) with some degree of alkaline enrichment (Glass 2007, 2010).|16-MAY-23
75949|Benning Gabbro|References|DUNDAS DL, Edgoose CJ, Fahey GM and Fahey JE, 1987. Daly River 1:100 000 Geological Map Series. Northern Territory Geological Survey Explanatory Notes (5070).  **EDGOOSE CJ, Fahey GM and Fahey JE, 1989. Wingate Mountains 1:100 000 Geological Map Series. Northern Territory Geological Survey Explanatory Notes (5069).  **GLASS LM, 2007. Geochemistry of mafic rocks in the Litchfield Province, western Pine Creek Orogen: Evidence for a Palaeoproterozoic arc-related setting and links to the Halls Creek Orogen: in 'Annual Geoscience Exploration Seminar (AGES) 2007. Record of Abstracts.' Northern Territory Geological Survey, Record 2007 001.  **GLASS LM, 2010. Palaeoproterozoic island-arc-related rocks of the Litchfield Province, western Pine Creek Orogen, Northern Territory. Northern Territory Geological Survey, Record 2010-005.  **NEEDHAM RS, Stuart-Smith PG, 1984. Geology of the Pine Creek Geosyncline, Northern Territory, 1:500 000 scale map. Bureau of Mineral Resources, Australian Bureau of Mineral Resources, Canberra. ACT.|16-MAY-23
30960|Bickerton Rhyolite|Name source|Bickerton Island in BLUE MUD BAY.|16-MAY-23
30960|Bickerton Rhyolite|Unit history|Outcrops at type area previously mapped as the now abandoned 'Bickerton Volcanics' (Plumb and Roberts, 1965, 1992). Some other outcrops previously mapped as 'Bickerton Volcanics' are now assigned to other units.|16-MAY-23
30960|Bickerton Rhyolite|Geomorphic expression|Low boulder-strewn hills.|16-MAY-23
30960|Bickerton Rhyolite|Type section locality|Northern edge of South Bay on Bickerton Island, lat. 13o 45' 30"S, long. 136o 09' 30"E (GR PE250770). Lower boundary locality: Covered interval at lat. 13o 45'S, long. 136o 09' 30"E (GR PE250775). Upper boundary locality: Covered interval on eastern side of South Bay at lat. 13o 48' 30"S, long. 163o 12'E (GR PE297735).|16-MAY-23
30960|Bickerton Rhyolite|Extent|Bickerton Island and southern part of Bustard Island, BLUE MUD BAY.|16-MAY-23
30960|Bickerton Rhyolite|Thickness range|Estimated maximum exposed thickness of 150-250m.|16-MAY-23
30960|Bickerton Rhyolite|Lithology|Red, porphyritc (K-feldspar) rhyolite.|16-MAY-23
30960|Bickerton Rhyolite|Depositional environment|Terrestrial, probably formed large domes and coulees.|16-MAY-23
30960|Bickerton Rhyolite|Relationships and boundaries|On Bustard Island this unit intrudes the Abarungkwa Sandstone. On Bickerton Island it is inferred to locally overlie the Abarungkwa Sandstone and is overlain by the Milyakburra Formation.|16-MAY-23
30960|Bickerton Rhyolite|Age reasons|Orosirian (Palaeoproterozoic). Dated by SHRIMP single-zircon U-Pb techniques at ~1814+/-8 Ma (Pietsch et al. 1994).|16-MAY-23
30960|Bickerton Rhyolite|Correlations|Considered to correlate with the ~1800-1840 Ma felsic volcanic suite widespread in northern Australia (Rawlings, 1994).|16-MAY-23
25685|Big Sunday Formation|Name source|Big Sunday, latitude 13o39'S, longitude 132o39'E STOW 1:100 000 Sheet area.|16-MAY-23
25685|Big Sunday Formation|Unit history|Walpole & others (1968) mapped these rocks as undifferentiated Edity River Volcanics and Masson Formation.|16-MAY-23
25685|Big Sunday Formation|Type section locality|On the South Alligator River 2 km SE of Big Sunday, area from GR 480875 (bottom) to GR 472867 (top) STOW 1:100 000 Sheet area. Fault at GR 476870 separates ignimbrite upper part from basalt-greywacke lower part.|16-MAY-23
25685|Big Sunday Formation|Extent|Well exposed in the South Alligator Valley between 3 km southeast of Coronation Hill and 7 km south of Big Sunday (STOW 1:100 000 Sheet area).|16-MAY-23
25685|Big Sunday Formation|Thickness range|At least 480 metres.|16-MAY-23
25685|Big Sunday Formation|Lithology|Lower sequence (280+ m thick) of fine to coarse micaceous feldspathic greywacke, green shale, tuffaceous chert, crystal tuff, micaceous siltstone overlain by an upper sequence at least 200 metres thick of interlayered amygdaloidal dark green basalt and flow banded massive rhyolite and ignimbrite.|16-MAY-23
25685|Big Sunday Formation|Relationships and boundaries|Conformably overlies the Pul Pul Rhyolite, contact defined by lowermost greywacke or tuff unit. Unconformably overlain by the Kurrundie Sandstone. Forms the upper unit of the El Sherana Group in the South Alligator Valley area and is probably a lateral equivalent of the Tollis Formation.|16-MAY-23
25685|Big Sunday Formation|Age reasons|Late Early Proterozoic (1800-1720 m.y.). It is part of the El Sherana Group which unconformably overlies metamorphosed Early Proterozoic sediments of the Pine Creek Geosyncline (1800 m.y.) and is probably a lateral equivalent of the Tollis Formation which is intruded by the Cullen Granite Complex (1780-1730 m.y.).|16-MAY-23
25685|Big Sunday Formation|Proposed publication|Geological map Commentary STOW 1:100 000 Sheet area|16-MAY-23
83015|Bills Formation|Name source|Bills Formation is named after Bills Dam (GDA94, 53K, 610623mE, 7878109mN), which lies approximately 30 km to the west of the type intersection of this unit.|16-MAY-23
83015|Bills Formation|Geomorphic expression|No known outcrops.|16-MAY-23
83015|Bills Formation|Type section locality|Drill hole NDIBK07 from down-hole depth 151.42 to 275.5 m (EOH). Collar at 641523mE 7877108mN (MGA94 zone 53)/ 19.194470S 136.346112E. Drill core is stored at the NTGS core library in Alice Springs.|16-MAY-23
83015|Bills Formation|Description at type locality|Lower interval (234.48-275.5 m) of poorly sorted, clast-supported sedimentary breccia, cataclasite and quartz-calcite fault infill. Sedimentary breccia is characterised by abundant angular clasts of phyllite of similar appearance to the Alroy Formation. Open fractures are present towards the bottom of this lower interval, including some that are rimmed with Mn-rich mineral (pyrolusite?) and/or hematite. Upper interval (151.42-234.48 m) of massive- to moderately-bedded lithic arenite and pebble-cobble conglomerate. The boundary between upper and lower intervals is marked by quartz fault-vein infill.|16-MAY-23
83015|Bills Formation|Extent|Unknown. Unlikely to extend to the southwest of type location, as it is absent in other boreholes in this direction. May extend to the northwest, north, east, and southeast.|16-MAY-23
83015|Bills Formation|General description|Only known in type interval. See description above.|16-MAY-23
83015|Bills Formation|Thickness range|Approximately 125 metres (apparent thickness only, true thickness is uncertain), in NDIBK07.|16-MAY-23
83015|Bills Formation|Lithology|Lithic arenite, conglomerate and breccia.|16-MAY-23
83015|Bills Formation|Relationships and boundaries|Overlain by Hinkler Formation at a sharp boundary (unconformity?). Bottom of unit is not constrained.|16-MAY-23
83015|Bills Formation|Identifying features|This unit is predominantly distinguished by its detrital zircon maximum depositional age (see below) and unique detrital zircon age spectrum, both of which are markedly different from data obtained from the overlying Hinkler Formation, or any other rocks at East Tennant (Kositcin, Cross et al. in prep).|16-MAY-23
83015|Bills Formation|Structure and Metamorphism|Little evidence of significant ductile deformation or metamorphism. Bedding is relatively flat-lying. The lower part of this unit has been strongly faulted and brecciated (see lithology description above).|16-MAY-23
83015|Bills Formation|Age reasons|A sample taken from 225.15?228.61 m down-hole depth from the type-interval returned an interpreted 207Pb/206Pb SHRIMP zircon maximum deposition age of 1844.6 +/- 3.9 Ma (Kositcin, Cross et al. in prep). Thus, the unit was deposited after 1844.6 +/- 3.9 Ma. Bills Formation is overlain by the Hinkler Formation, which has an interpreted 207Pb/206Pb SHRIMP zircon maximum deposition age of 1652 +/- 24 Ma.|16-MAY-23
83015|Bills Formation|Correlations|The broad constraints on the age of this unit preclude robust comparisons to any contemporary units. If the unit?s maximum deposition age is close to the true age of deposition, then this unit would be similar in age, and some lithological aspects, to the Ooradidgee Group of the Warramunga Province. It would also have been deposited at around the same time as, or just after, the Cliffdale Volcanics of the Murphy Province.|16-MAY-23
83015|Bills Formation|Alteration and Mineralisation|Lower part of this unit is strongly faulted and silicified. Open spaces are partially infilled with quartz, calcite, specular hematite and pyrolusite (manganese oxide).|16-MAY-23
83015|Bills Formation|Geophysical Expression|Down-hole geophysical data were not available for this interval due to borehole collapse after drilling. There are no obvious features in regional magnetics or gravity imagery that are attributable to this unit.|16-MAY-23
83015|Bills Formation|Defn author|A. D. Clark 24-MAR-2022.|16-MAY-23
83015|Bills Formation|Proposed publication|Schofield and Clark et al., (in prep). Geology of the East Tennant area, Northern Territory, journal publication.|16-MAY-23
83015|Bills Formation|References|Kositcin, N., Cross A.J., et al., in prep. Geochronology of the East Tennant area, Geoscience Australia Record.|16-MAY-23
76182|Birraduk Amphibolite|Name source|After Birraduk Creek on Oenpelli SD 5573 1:100 000 mapsheet (see Geoscience Australia Place Name Search: http://www.ga.gov.au/place-name/; Record ID - NT 10858) GDA 94 53L, 302464mE 8661640mN (-12º6'3"S 133º11'6"E) on Alligator River 1:250 000 and Oenpelli1:100 000 mapsheets, Nimbuwah Domain, Pine Creek Orogen.|16-MAY-23
76182|Birraduk Amphibolite|Unit history|Zamu Complex (in part; Stewart 1959 unpublished, as cited in Ferguson and Needham 1978, modified Bryan 1962 and Walpole 1962); Zamu Dolerite (in part; Ferguson and Needham 1978).|16-MAY-23
76182|Birraduk Amphibolite|Geomorphic expression|Exposed in small creek system; elsewhere, known from drill core close to major faults in Kombolgie Subgroup.|16-MAY-23
76182|Birraduk Amphibolite|Type section locality|Amphibolite exposed in small creek in northwestern Myra Falls Inlier, Oenpelli 1:100 000 mapsheet. GDA 94 53L 309081mE 8628329mN (-12°24'8"S 133°14'38"E).|16-MAY-23
76182|Birraduk Amphibolite|Description at type locality|Well exposed in creek with strongly defined east¿west-trending foliation defined by amphibole and biotite|16-MAY-23
76182|Birraduk Amphibolite|Extent|Restricted to areas described  in General Description.|16-MAY-23
76182|Birraduk Amphibolite|General description|Occurs in northwestern Myra Falls Inlier and also intersected in drill core along fault systems in nearby Kombolgie Subgroup (7.5 km northeast and 6.5 km east of type locality, Oenpelli 1:100 000 mapsheet).|16-MAY-23
76182|Birraduk Amphibolite|Thickness range|Not known.|16-MAY-23
76182|Birraduk Amphibolite|Lithology|Fine-grained amphibolite with strong schistosity. Foliation defined by hornblende and biotite (which encircles elongate feldspar).|16-MAY-23
76182|Birraduk Amphibolite|Depositional environment|/Genesis: Probably originally an intrusive rock|16-MAY-23
76182|Birraduk Amphibolite|Relationships and boundaries|Contact relationships with surrounding strata not observed, but occurs within Palaeoproterozoic Cahill Formation and Nourlangie Schist.|16-MAY-23
76182|Birraduk Amphibolite|Identifying features|Fine-grained and strongly foliated, often garnet-bearing.|16-MAY-23
76182|Birraduk Amphibolite|Structure and Metamorphism|Amphibolite-facies metamorphism|16-MAY-23
76182|Birraduk Amphibolite|Age reasons|Not adequately constrained, but most likely Palaeoproterozoic as occurs within Palaeoproterozoic Cahill Formation and Nourlangie Schist.|16-MAY-23
76182|Birraduk Amphibolite|Correlations|None known.|16-MAY-23
76182|Birraduk Amphibolite|Alteration and Mineralisation|Sericite alteration of feldspar and chlorite alteration of amphibole. No known mineralisation.|16-MAY-23
76182|Birraduk Amphibolite|Geophysical Expression|Too small to be expressed in geophysical imagery.|16-MAY-23
76182|Birraduk Amphibolite|Geochemistry|Mainly quartz-hypersthene normative in composition.|16-MAY-23
76182|Birraduk Amphibolite|Defn author|LM Glass and JA Hollis, 2012.|16-MAY-23
76182|Birraduk Amphibolite|References|Bryan R, 1962. Lower Proterozoic basic intrusive rocks of the Katherine-Darwin area, Northern Territory. Bureau of Mineral Resources, Australia, Record 1962/07.***Walpole BP, 1962. Mount Evelyn, Northern Territory, 1:250 000 Geological Series Explanatory Notes, SD53/5. Bureau of Mineral Resources, Australia, Canberra.***Ferguson J and Needham RS, 1978. The Zamu Dolerite: A lower Proterozoic preorogenic continental tholeiitic suite from the Northern Territory, Australia. Journal of the Geological Society of Australia 25(6), 309-322.|16-MAY-23
79261|Bitter Springs Group|Name source|Bitter Springs Limestone was named after Bitter Springs Gorge (GDA94, 53K, 446551mE, 7397552mN) approximately 64 km eastnortheast of Alice Springs by Jöklik (1955).|16-MAY-23
79261|Bitter Springs Group|Unit history|Previously Bitter Springs Limestone of Jöklik (1955). The name was revised to Bitter Springs Formation by Ranford et al (1965), and is still in common use.|16-MAY-23
79261|Bitter Springs Group|Constituents|Gillen Formation, Loves Creek Formation, Johnnys Creek Formation.|16-MAY-23
79261|Bitter Springs Group|Geomorphic expression|Limestone and dolostone units of the Bitter Springs Group typically form large, sharp ridges or rounded hills.|16-MAY-23
79261|Bitter Springs Group|Type section locality|Type Locality: Approximately 800 m of at times poorly exposed section along the  eastern bank of creek, a tributary to Ellery Creek Waterhole (GDA94, 53K, 303738mE, 7369102mN) at Ellery Creek (HERMANNSBERG).|16-MAY-23
79261|Bitter Springs Group|Description at type locality|Up to 800m of limestone and argillaceous siltstone. The lower 30m is poorly exposed and overprinted by folding however it is clear that beds are not repeated or missing. Most of the limestone within this section is hard, dark, grey, dolomitic and cherty limestone which is well bedded and often laminated. Siltstone is typically recessive and dark, laminated, calcareous and argillaceous. The middle part of the section comprises largely red mudstone with interbedded thin beds of pale grey limestone. The upper section consists of massive limestone that is stromatolitic and cherty. The uppermost 30 to 40m is not exposed.|16-MAY-23
79261|Bitter Springs Group|Extent|The Bitter Springs Group is widely distributed across the basin. Within the northeastern part the basin Bitter Springs Group is exposed to the south of the ridge of Heavitree Quartzite that extends across HERMANNSBERG, ALICE SPRINGS and into the southwestern portion of ILLOGWA CREEK.|16-MAY-23
79261|Bitter Springs Group|Thickness range|Due to folding and halotectonism exact thickness of the Bitter Springs Group is difficult to ascertain, at the type locality the unit is approximately 800 m thick. Kennard et al (1986) estimated that the approximate thickness of the group (then Bitter Springs Formation) to be approximately 1350m. The Gillen Formation at its type section is 1505 m thick, the Loves Creek Formation is approximately 500m and the Johnnys Creek Formation is about 360 m thick at its type section, this would infer a maximum thickness of the Bitter Springs Group to be approximately 2365m. This is further evidence that the folding and halotectonism has thickened and shortened the group significantly and a true thickness is difficult to determine. Due to folding and halotectonism the thickness of the unit varies from <100m to 1350m.|16-MAY-23
79261|Bitter Springs Group|Lithology|Dolostone, limestone and cherty limestone and dolostone, with subordinate sandstone, red and green siltstone and shale.|16-MAY-23
79261|Bitter Springs Group|Depositional environment|The carbonate-dominant rocks of the Bitter Springs Group suggests that it was deposited on a shallow, stable shelf setting. The presence of thin beds of sandstone throughout the unit indicate a small amount of fine-grained siliciclastic input. The presence of stromatolitic units shows that deposition was in shallow water despite the thickness of the formation (Prichard and Quinlan 1962).|16-MAY-23
79261|Bitter Springs Group|Fossils|Stromatolites are common. Tungussia erecta of the Gillen Formation; stromatolites of the Accaciella australica assemblage of the Loves Creek Formation and presently un-named stromatolites of the Johnnys Creek Formation (Grey et al 2012, Walter 1972). Other fossils include spheroidal acritarchs in the Gillen Formation (Walter 1972) and Loves Creek Formation (Zang and Walter 1992);  microfossils in black chert of the Johnnys Creek Formation (Schopf 1968).|16-MAY-23
79261|Bitter Springs Group|Diastems or hiatuses|None described at type locality. Menpes (1991) suggest the presence of an angular unconformity between the Gillen and Loves Creek formations and Southgate (1991) described a disconformity between the Loves Creek and Johnnys Creek formations.|16-MAY-23
79261|Bitter Springs Group|Relationships and boundaries|The Bitter Springs Group overlies quartzite of the Heavitree Quartzite in a sharp contact in some parts of the northeast of the Amadeus Basin and is a gradational and conformable contact in others; the dark grey siltstone of the Bitter Springs Group is easily distinguishable from the pale yellow-brown siltstone units of the Heavitree Quartzite. The upper boundary of the section is partially not exposed however the section has been measured at the change from almost black siltstone to fine-grained greywacke which is the basal beds of the overlying Areyonga Formation.|16-MAY-23
79261|Bitter Springs Group|Structure and Metamorphism|Carbonate rocks are generally massive with occasional bedding and laminations, siltstone units are laminated.|16-MAY-23
79261|Bitter Springs Group|Age reasons|The upper part of the Bitter Springs Group has a well-constrained age of ca 820 Ma; this is based on the presence of layers of basalt in the Johnnys Creek Formation. These basalts have been geochemically correlated with the ca. 824 Ma Amata Dolerite of the Musgrave Province which has a U-Pb baddeleyite age of 824 +/- 4 Ma (Glikson et al 1996, Zhao et al 1992). This is also supported by isotope and geochemical studies (Barovich and Foden 2000, Hill et al 2000, Hill and Walter 2000, Lindsay et al 2005) of the Bitter Springs Group which suggest that it is a correlative of the Coominaree Dolomite of the Adelaide Fold Belt and the Browne Formation of the Officer Basin (Hill 2005, Hill and Walter 2000). The lower Bitter Springs Group is less constrained. New SHRIMP U-Pb detrital zircon dating yielded a maximum depositional age of 896 +/- 24 Ma (2sigma) for informal member 3 of the Gillen Formation (Kositcin et al 2014a), suggesting that the Gillen Formation is at least 896 million years old. The underlying Heavitree Quartzite has maximum depositional ages ranging between ca 1050 to 1000 Ma (Camacho et al 2002, Kositcin et al 2014b, Maidment 2005, Maidment et al 2007). This new data combined with existing data suggests that the Bitter Springs Group can be constrained to between ca. 1000 Ma and ca. 820 Ma. Recent in situ U-Pb dating of zircon from basalt lava in the Johnnys Creek Formation  yielded an igneous crystallisation age of 767 +/- 130 Ma (n = 4) (Thompson et al 2015). It must be noted that this age is based on a small number of analyses and though it is plausible on the basis of a number of independent geological considerations, it is only preliminary pending analysis of a greater number of zircons.|16-MAY-23
79261|Bitter Springs Group|Correlations|Pinyinna beds are a lateral equivalent of the Bitter Springs Group (Close et al 2003), these are sporadically exposed along the southwestern margins of the Amadeus Basin.|16-MAY-23
79261|Bitter Springs Group|Alteration and Mineralisation|Carbonate rocks are typically dolomitic and silicified in areas where folding and halotectonism has occurred. Mineralisation summarised from Edgoose (2013): Gold mineralisation within the Bitter Springs Group has been noted in the Winnecke goldfield. Silver and base metal mineralisation is within the Bitter Springs Group at the Blueys Prospect at sub-economical grades. Copper mineralisation generally associated with the basalts of the Johnnys Creek Formation has been recorded at the Bronco Bore, Undoolya Gap prospects as well as a number of unnamed occurrences. Manganese occurrences have been reported in the Bitter Springs Group at the Fenn Gap Mn prospect, southwest of Alice Springs. Gypsum and other evaporites have been recorded within the Bitter Springs Group, generally associated with dolostone diapirs. Petroleum: All the formations within the Bitter Springs Group have been identified as potential petroleum source rocks (Munson 2014) and are part of the petroleum systems as identified by Marshall et al (2007).|16-MAY-23
79261|Bitter Springs Group|Geophysical Expression|The Gillen Formation is clearly seen in seismic imaging due to the salt that is contained within the unit. Due to the relative thinness of the Loves Creek Formation and Johnnys Creek Formation  these units are not commonly expressed in geophysics.|16-MAY-23
79261|Bitter Springs Group|Geochemistry|Nowland (2008) reported that basalt lavas within the Johnnys Creek Formation have been altered, but inferred that they are most likely tholeiitic and geochemically comparable to intraplate basalts. Nowland (2008) reported that these basalts generally have gently uniformly sloped chondrite normalised REE patterns, while the least altered samples have enrichment of LREE relative to HREE but generally flat LREE patterns and concluded that melt compositions are controlled by preferential melting of clinopyroxene in the source. The basalts also have slight negative Eu-anomalies contrary to the slight positive anomalies that would be expected if clinopyroxene controlled melt compositions. Fractional crystallisation of plagioclase can reconcile these contrary indications. Nowland (2008) further concluded from Sm-Nd and Rb-Sr isotopic data that the basalts had a source composition comparable to CHUR rather than either a depleted or enriched mantle source, and are consistent with, but do not confirm, a plume-related source. Although the Johnnys Creek Formation basalts are geochemically similar to the Gairdner and Amata dolerites (Nowland 2008, Zhao et al 1994), recently determined preliminary geochronological data reported above suggests that the basalts are not comagmatic with these dolerites.|16-MAY-23
79261|Bitter Springs Group|Defn author|Authors: VJ Normington, N Donnellan.  Approved 20-NOV-2015.|16-MAY-23
79261|Bitter Springs Group|References|Barovich KM and Foden J, 2000. A Neoproterozoic flood basalt province in southern-central Australia: geochemical and Nd isotope evidence from basin fill. Precambrian Research 100, 213-234. **Camacho A, Hensen B and Armstrong R, 2002. Isotopic test of a thermally driven intraplate orogenic model, Australia. Geology 30, 887-890. **Close DF, Edgoose C and Scrimgeour IR, 2003. Hull and Bloods Range, Northern Territory. 1: 100 000 geological map series explanatory notes 4748, 4848: in Survey NTG (editor). Darwin. **Edgoose C, 2013. Amadeus Basin: in Ahmad M and Munson TJ (editors) 'Geology and mineral resources of the Northern Territory; Special Publication 5', Northern Territory Government. **Glikson AY, Stewart AJ, Ballhaus CG, Clarke GL, Feeken EHJ, Leven JH, Sheraton JW and Shensu-Sun, 1996. Geology of the western Musgrave Block, central Australia with particular reference to  the mafic-ultramafic Giles Complex. Australian Geologlogical Survey Organisation Bulletin 239. **Grey K, Allen HJ, Hill AC and Haines PW, 2012. Neoproterozoic biostratigraphy of the Amadeus Basin 'Central Australian Basins Symposium III '. Alice Springs **Hill AC, 2005. Stable isotope stratigraphy, GSWA Lancer 1, Officer Basin in Mory AJ and Haines PW (editors) 'GSWA Lancer 1 well completion report (Interpretive papers), Officer and Gunbarrel basins, Western Australia.' Record 2005/4, Geological Survey of Western Australia, 1-11. **Hill AC, Cotter KL and Grey K, 2000. Nid-Neoproterozoic biostratography and isotope stratigraphy in Australia. Precambrian Research 100, 281-298. **Hill AC and Walter MR, 2000. Mid-Neoproterozoic (~830 - 750 Ma) isotope stratigraphy of Australia and global correlation. Precambrian Research 100, 181-211. **Jöklik, GF, 1955. The geology of the mica fields of the Harts Range, central Australia. BMR, Bulletin 26. Bureau of Mineral Resources of Australia. **Kennard JM, Nicoll RS and Owen M, 1986. Late Proterozoic and early Proterozoic depostional facies of the northern Amadeus Basin, central Australia. Sediments Down-Under. 12th International Sedimentological Congress, Canberra, Australia. 24 - 30 August 1986. Field Excursion 25B. **Kositcin N, Normington V and Edgoose C, 2014a. Summary of results. Joint NTGS - GA geochronology project: Amadeus Basin, July 2013 - June 2014. NTGS Record 2015-001, Northern Territory Geological Survey. **Kositcin N, Whelan JA, Hallett L and Beyer EE, 2014b. Summary of results. Joint NTGS-GA geochronology project: Amadeus Basin, Arunta Region and Murphy Province, July 2012 - June 2013. NTGS Record 2014-005. Darwin, Northern Territory Geological Survey. **Lindsay JF, Kruse PD, Green OR, Hawkins E, Braiser MD, Cartlidge J and Corfield RM, 2005. The Neoproterozoic-Cambrian record in Australia: A stable isotope study. Precambrian Research 143, 113-133. **Maidment DW, 2005. Palaeozoic high-grade metamorphism within the Centralian Superbasin, Harts Range region, central Australia, Australian National Univeristy Canberra. **Maidment DW, Williams IS and Hand M, 2007. Testing long-term patterns of basin sedimentation by detrital zircon geochronology, Centralian Superbasin, Australia. Basin Research 19, 355-360.|16-MAY-23
79261|Bitter Springs Group|References|Marshall TR, Dyson IA and Liu Keyu, 2007. Petroleum systems in the Amadeus Basin, central Australia: Were they oil prone?: in Munson TJ and Ambrose GJ (editors) 'Proceedings of the Central Australian Basins Symposium, Alice Springs, 16 - 18th August, 2005'. Alice Springs, Northern Territory Geological Survey, Special Publication 2, 136-146. **Munson TJ, 2014. Petroleum geology and potential of the onshore Northern Territory, 2014, Northern Territory Geological Survey, Report 22. **Normington VJ and Donnellan N, in prep. Characterisation of the Neoproterozoic stratigraphy of the northeast Amadeus Basin, Northern Territory. Record 2015-##, Northern Territory Geological Survey. **Nowland J, 2008. What caused the Rodinia breakup? Integrating basalt geochemisrty and sedimentology to assess the plume model for Rodinia breakup. BSc (Hons) thesis, James Cook University. **Prichard CE and Quinlan T, 1962. The geology of the southern half of the Hermannsburg 1:250 000 sheet. BMR Report No. 61. Bureau of Mineral Resources Geology and Geophysics. **Ranford LC, Cook PJ and Wells AT, 1965. The Geology of the central part of the Amadeus Basin, Northern Territory. BMR Report No. 86. Canberra, Bureau of Mineral Resources, Geology and Geophysics. **Schopf JW, 1968. Microflora of the Bitter Springs formation, late Precambrian, central Australia. Journal of Paleontology 42, 651-688. **Southgate PN, 1991. A sedimentological model for the Loves Creek Member of the Bitter Springs Formation, northern Amadeus Basin: in Korsch RJ and Kennard J (editors) 'Geological and geophysical studies in the Amadeus Basin, central Australia. ' Bulletin 236. Australia, Bureau of Mineral Resources, 113-126. **Thompson J, Meffre S, Goemann K and Zhukova I, 2015. CODES, ARC Centre of Excellence in Ore Deposits, University of Tasmania, Australia, unpublished report., 4. **Walter MR, 1972. Stromatolites and the biostratigraphy of the Australian Precambrian and Cambrian. Special Publication Palaeontology 11. **Zang W and Walter MR, 1992. Late Proterozoic and Cambrian microfossils and biostratigraphy, Amadeus Basin, central Australia. Association of Australasian Palaeontologists Memoir 12. **Zhao J, McCullouch MT and Korsch RJ, 1994. Characterisation of a plume-related ~800 Ma magmatic event and its implications for basin formation in central-southern Australia. Earth and Planetary Science Letters 121, 349-367. **Zhao JX and McCullouch MT, 1993. Sm-Nd isochron ages of Late Proterozoic dyke swarms in Australia: evidence for two distinctive events of mafic magmatism and crustal extension. Chemical Geology 109, 341-354. **Zhao JX, McCullouch MT and Bennett VC, 1992. Sm-Nd and U-Pb isotopic constraints on the provenance of sediments from the Amadeus Basin, central Australia; Evidence for REE fractionation. Geochemica et Cosmochimica Acta 56, 921-940.|16-MAY-23
1843|Black Stump Arkose|Name source|Black Stump Dam, Hay River 1:250 000 Geological Series sheet.|16-MAY-23
1843|Black Stump Arkose|Unit history|Part of the Field River Beds of Smith (1963).|16-MAY-23
1843|Black Stump Arkose|Type section locality|A composite section compiled from the observation of outcrops in the triangular fault block 0-4 km N by W of Hay River No. 7 (Adam Special 1:100 000 Geological Sheet).|16-MAY-23
1843|Black Stump Arkose|Extent|The formation is exposed on the Tobermory, Hay River and Mt Whelan 1:250 000 Sheet areas.|16-MAY-23
1843|Black Stump Arkose|Thickness range|An estimated minimum of 700 m in the type area, and a minimum of 500 m on the southern limb of the Desert  Syncline (northern Adam Special 1:100 000 Sheet area). Thicknesses are calculated from aerial photographs; in addition, use was made in calculating the thickness of the type section of a measured section in K.G. Smith's 1959 Hay River notebook. Thicknesses are unknown elsewhere.|16-MAY-23
1843|Black Stump Arkose|Lithology|Medium red-brown to dark purple-brown micaceous fine to very coarse-grained arkose, pebbly arkose, sandstone and laminated micaceous siltstone and shale.|16-MAY-23
1843|Black Stump Arkose|Relationships and boundaries|The unit disconformably overlies the Yardida Tillite (Walter, 1979). On the southern limb of the Desert Syncline and at Boat Hill (Tobermory 1:250 000 Sheet area) it rests on the dolomitic shale at the top of the tillite. Elsewhere (e.g. Hay River No. 7 drillhole the dolomitic shale has been eroded off and the Arkose overlies diamictite. The upper boundary is placed at the base of the first prominent dolomite bed of the Wonnadinna Dolomite 4.7 km NNE of Gnallan-a-gea Bore (Hay River 1:250 000 Geological Sheet; Adam Special 1:100 000 Geological Sheet). The upper boundary is considered to be gradational as red-brown arkose and dolomitic arkose are components of the Wonnadinna Dolomite.|16-MAY-23
1843|Black Stump Arkose|Age reasons|Adelaidean. Stratigraphic position and regional correlations strongly suggest equivalence to the upper of the two major late Proterozoic tillites.|16-MAY-23
1896|Blanche Creek Member|Name source|Blanche Creek in the Tennant Creek 1:250 000 Sheet area (latitude 19o02'S, longitude 134o09'E).|16-MAY-23
1896|Blanche Creek Member|Type section locality|Near GR 411885. At this locality the formation consists of poorly sorted pebbly sandstone and conglomerate, as described under Lithology. Pebbles 1-6 cm across account for up to 20 percent of the rock. Shows high angle ("torrential") cross-bedding.|16-MAY-23
1896|Blanche Creek Member|Extent|Scattered outcrops along the eastern side of the Whittington Range as far south as Hayward Creek. It is also found along the southern edge of the Short Range.|16-MAY-23
1896|Blanche Creek Member|Thickness range|Up to 150 m.|16-MAY-23
1896|Blanche Creek Member|Lithology|Poorly sorted pebbly lithic sandstone and conglomerate, consisting of 20-30 percent sub-rounded pebbles in a lithic sandstone matrix. The pebbles are predominantly of white quartz; about 10 percent are of black chert, red jasper, acid igneous rocks (quartz porphyries) and rarely dark red-purple siltstone and shale fragments.|16-MAY-23
1896|Blanche Creek Member|Relationships and boundaries|Overlies the Early Proterozoic Warramunga Group, locally with slight angular unconformity. It is the basal member of the Hayward Creek G Formation, and passes up conformably into this formation.|16-MAY-23
1896|Blanche Creek Member|Identifying features|Name of Host Formation: Hayward Creek Formation|16-MAY-23
1896|Blanche Creek Member|Age reasons|By assumed correlation of Tomkinson Creek Beds with Hatches Creek Group, late Early Proterozoic to Early Carpentarian.|16-MAY-23
1896|Blanche Creek Member|Proposed publication|See References under Mendum and Tonkin; Dodson and Gardener|16-MAY-23
1931|Blatherskite Quartzite Member|Name source|Mount Blatherskite (GR 38393726) in the Alice Springs 1:250 000 Sheet area.|16-MAY-23
1931|Blatherskite Quartzite Member|Unit history|The Heavitree Quartzite has been previously undivided (Wells & others, 1968) except informally in the Arltunga Nappe Complex (Shaw & others, 1971).|16-MAY-23
1931|Blatherskite Quartzite Member|Type section locality|Heavitree Gap (GR 3845 3745)|16-MAY-23
1931|Blatherskite Quartzite Member|Lithology|Well-sorted, very fine to medium-grained quartz sandstone with rare silty interbeds. A 28 m thick, poorly-sorted unit of sandstone occurs in the upper part. The unit is mainly medium to thick-bedded, but includes some thin beds in the lowermost and uppermost parts.|16-MAY-23
1931|Blatherskite Quartzite Member|Relationships and boundaries|The unit conformably overlies the Fenn Gap Conglomerate Member and is conformably overlain by the Bitter Springs Formation.|16-MAY-23
1931|Blatherskite Quartzite Member|Age reasons|Upper Proterozoic (see reverse side Temble Bar SS Member).|16-MAY-23
1931|Blatherskite Quartzite Member|Comments|Remarks: The boundary with the overlying Bitter Springs Formation is not exposed at Heavitree Gap, but elsewhere the base of the Bitter Springs Formation is taken to be the first appearance of a significant thickness (greater than 1 m) of siltstone.|16-MAY-23
36765|Bloods Range Formation|Name source|Bloods Range, northeastern Hull and northwestern Bloods Range 1:100 000 mapsheets.|16-MAY-23
36765|Bloods Range Formation|Unit history|Bloods Range beds, Bloods Range Beds (Forman 1966).|16-MAY-23
36765|Bloods Range Formation|Constituents|Nil|16-MAY-23
36765|Bloods Range Formation|Geomorphic expression|Footslopes below scarps of strike ridges of Dean Quartzite and Kulail Sandstone, rarely as isolated low hills.|16-MAY-23
36765|Bloods Range Formation|Type section locality|Upper and lower stratigraphic contacts exposed on southern slope of Bloods Range, 11 km west of Mount Harris at location 24o 38' 15.96" S, 129o 24' 22" E (WGS 84).|16-MAY-23
36765|Bloods Range Formation|Description at type locality|Lower contact is polymictic conglomerate with interlayered quartzose sandstone beds above weathered porphyritic rhyolite. Upper contact is interlayered red siltstone and quartz sandstone beds with a 50 cm top layer of leached clay below quartzofeldspathic sandstone beds. Thickness of section is approximately 80 m.|16-MAY-23
36765|Bloods Range Formation|Extent|Mount Berteaux region (northwestern Petermann ranges 1:250 000 mapsheet), Manananna Range, Mount Skene Range, Mount Hastie area, Bloods Range, Rowley Range (Hull and Bloods Range 1:100 000 mapsheets).|16-MAY-23
36765|Bloods Range Formation|Thickness range|Laterally variable, on average approximately 100 m.|16-MAY-23
36765|Bloods Range Formation|Lithology|Polymict pebble conglomerate (possible debris flows), quartzite-cobble conglomerate, immature sandstone, red and dark fine grained sandstone and siltstone, epiclastic and volcaniclastic rocks, rare tuffs. Thickness and presence/absence of these lithologies varies from outcrop to outcrop. Sediments are very locally derived, therefore sequence vary considerably with composition of the substrate source.|16-MAY-23
36765|Bloods Range Formation|Depositional environment|Fluvial and probably lacustrine environments contemporaneous with extrusive activity.|16-MAY-23
36765|Bloods Range Formation|Relationships and boundaries|Unconformably overlain by Kulail Sandstone and overlies Puntitjata Rhyolite, Mount Harris Basalt and Musgrave Block granites.|16-MAY-23
36765|Bloods Range Formation|Age reasons|Meso-Neoproterozoic. Older than Dean Quartzite (~850 Ma) and younger than Puntitjata Rhyolite (1075 +/- 2.5 Ma).|16-MAY-23
36765|Bloods Range Formation|Correlations|Originally correlated with Dixon Range beds (WA) which are defined by Forman (1966) as conformable beneath the Dean Quartzite. However redefinition precludes this correlation as the contact between the Bloods Range Formation and the Kulail Sandstone/Dean Quartzite in the Bloods Range region is defined by an erosional disconformity.|16-MAY-23
36765|Bloods Range Formation|Proposed publication|Close, D.F., Edgoose, C.J., Scrimgeour, I.R., 2002. Bloods Range and Hull 1:100 000 geological special, Northern Territory Geological Survey, Explanatory notes.|16-MAY-23
36765|Bloods Range Formation|Comments|Former name Bloods Range beds included parts of newly defined Tjuninanta Formation and Kulail Sandstones. The Bloods Range Formation forms the uppermost unit of the Tjauwata Group. True thickness of sequence difficult to measure due to both upper and lower stratigraphic contact rarely exposed in same section, and strong foliation development during the 570-530 Ma Petermann Orogeny.|16-MAY-23
36765|Bloods Range Formation|References|R087 -   Forman, D.J., 1966. The geology of the south-western margin of the Amadeus Basin, central Australia. Bureau of Mineral Resources, Australia. Report, 87.|16-MAY-23
24190|Boko Formation|Name source|Boko Bore on Mount Peake 1:250 000 sheet (AMG GR LS3409).|16-MAY-23
24190|Boko Formation|Unit history|Originally included in Central Mount Stuart beds at AMG GR LS508143 on Barrow 1:100 000 sheet, elsewhere incorrectly mapped as Archaean basement or granite (Smith & Milligan, 1964).|16-MAY-23
24190|Boko Formation|Geomorphic expression|Low rounded hills covered with loose cobbles.|16-MAY-23
24190|Boko Formation|Type section locality|10 km north of Junction Well on Barrow 1:100 000 sheet (AMG GR LS510200; latitude 21o31'05"S, longitude 133o33'30"E).|16-MAY-23
24190|Boko Formation|Extent|Known only from four outcrops in the northwestern corner of the Barrow 1:100 000 sheet.|16-MAY-23
24190|Boko Formation|Thickness range|Estimated preserved thickness 20 m at type locality (top not exposed).|16-MAY-23
24190|Boko Formation|Lithology|Massive diamictite interpreted as a tillite. Clasts, up to 2 m diameter, often faceted and striated. Clast types include quartzite, granite, and various volcanics and metamorphics. The rarely exposed matrix consists of red-brown poorly-lithified mudstone.|16-MAY-23
24190|Boko Formation|Relationships and boundaries|Unconformably overlies early Proterozoic crystalline basement and Late Proterozoic Amesbury Quartzite at type locality. Disconformably overlain by Tops Member of late Proterozoic Central Mount Stuart Formation at AMG GR LS552138.|16-MAY-23
24190|Boko Formation|Structure and Metamorphism|Generally horizontal to very gently dipping. Steeply dipping at AMG GR LS508143.|16-MAY-23
24190|Boko Formation|Age reasons|Late Proterozoic based on superposition.|16-MAY-23
24190|Boko Formation|Correlations|Correlated with similar unnamed diamictite lying below Central Mount Stuart Formation at AMG GR LR2861 on Alcoota 1:250 000 sheet (Shaw et al., 1975). Tentatively correlated with Marinoan late Proterozoic glacial episode of Adelaide Geosyncline. Hence, tentatively correlated with the Olympic Formation of Amadeus Basin and Mount Doreen Formation of Ngalia Basin.|16-MAY-23
35951|Bond Springs Gneiss|Name source|Bond Springs homestead, GR 5650-897960 Alice Springs 1:100 000 Sheet area.|16-MAY-23
35951|Bond Springs Gneiss|Type section locality|North of homestead along tributary of Todd River: GR 5650-897964 to 897973. Leucocratic gneiss and muscovite schist.|16-MAY-23
35951|Bond Springs Gneiss|Extent|Occur in an arc (about 9 km strike length by about 2 km width) in the northeast of the Alice Springs 1:100 000 Sheet area near Bond Springs homestead.|16-MAY-23
35951|Bond Springs Gneiss|Lithology|Leucocratic medium-grained quartzfeldspathic and garnet-muscovite gneiss and lesser amounts of banded biotite gneiss, amphibolite and muscovite schist; southern part of gneiss is partly migmatitic.|16-MAY-23
35951|Bond Springs Gneiss|Relationships and boundaries|Structurally overlain to the west and underlain to the east by unnamed gneiss; contacts are concordant with the foliation.|16-MAY-23
35951|Bond Springs Gneiss|Identifying features|Reason for proposed name: Distinctive unit of leucocratic gneiss; surrounding rocks are composed of darker-coloured gneiss.|16-MAY-23
35951|Bond Springs Gneiss|Age reasons|No direct evidence. Recrystallisation and metamorphic fabric of the unit may have occurred during the regional Chewings Phase of deformation which in Hermannsburg 1:100 000 Sheet area to the west has been dated by total-rock Rb-Sr at 1620+/-70 m.y.|16-MAY-23
35951|Bond Springs Gneiss|Proposed publication|Geological report on 1:100 000 scale mapping of southeastern Arunta Block, Alice Springs 1:250 000 Sheet area, Northern Territory by R.D. Shaw et al. BMR.  Microfiche report in prep.|16-MAY-23
28387|Bonya Metamorphics|Name source|Bonya Creek in vicinity of 624000mE, 7278000mN (in GDA94, Zone53), in central JERVOIS RANGE 1:100 000 Sheet area.|16-MAY-23
28387|Bonya Metamorphics|Unit history|First defined by RG Warren in 1979 as 'Bonya metamorphic complex' (with definition card). Later revised as 'Bonya Metamorphic Complex' by Stewart et al. (1980). Later redefined by RD Shaw in 1988 as 'Bonya Schist' based on Shaw et al. (1985). Variation of published name is 'Bonya Metamorphics', which was used by G Warren and R Thorpe in 1994 and Warren et al. (1995).|16-MAY-23
28387|Bonya Metamorphics|Geomorphic expression|Generally forms a steeply dipping succession of low rises and ridges with cm- to m-wide, sub-vertical plates and sheets, isolated rounded boulders and block-like outcrops. Sub-crop is common in recessive lithologies. In the Jervois mineral field and Bonya Hills area, the Bonya Metamorphics form hills that rise 50-100m above the surrounding Quaternary plains.|16-MAY-23
28387|Bonya Metamorphics|Type section locality|No single outcrop contains all informal subunits of the Bonya Metamorphics. Type localities of the subunits are (in latitude-longitude, and UTM GDA94, Zone 53):   Informal subunit porphyroblastic schists and mica-bearing metasandstones: An area around and north of the Marshall-Reward open pit of the Jervois mineral field (16.26634°E, 22.65705°S; 630109mE, 7493890mN). Access via public roads and private tracks. Informal subunit mica schists: An area ~1.5 km northeast of Marshall-Reward (136.27993°E, 22.63951°S; 631523mE, 7495820mN). Access via public roads and private tracks. Informal subunit calc-silicate rocks interlayered with informal subunit porphyroblastic schists: An area close to Tashkent tungsten occurrence (136.14255°E, 22.740840°S; 617334mE, 7488308mN). Access via public roads and private tracks. Informal subunit layered quartz-magnetite-hematite rocks: At locations south and east of the Jervois mineral field (136.29025°E, 22.68890°S; 632536mE, 7490343mN, and 136.24011°E, 22.71754°S; 627358mE, 7487216mN). Access via public roads. Informal subunit tourmalinites: At a location in the Jervois mineral field (136.27130°E, 22.64602°S; 630630mE, 7495107mN). Access via public roads and company tracks.|16-MAY-23
28387|Bonya Metamorphics|Description at type locality|The Bonya Metamorphics are a meta-sedimentary succession consisting of six informal and unnamed members of interlayered meta-mudstones, meta-sandstones and meta-carbonates, including minor occurrences of meta-exhalites and meta-porphyries.|16-MAY-23
28387|Bonya Metamorphics|Extent|Primary occurrence is in the JERVOIS RANGE 1:100 000 Sheet between the Charlotte Fault Zone in the west, the Lucy Creek Fault Zone in the east and north of the Delny Shear Zone, main outcrop areas are centred around 136.05166°E, 22.72084°S; 608000mE, 7487000mN (Bonya Hills) and 136.26535°E, 22.66510°S; 630000mE, 7493000mN (Jervois mineral field). A minor occurrence of possible Bonya Metamorphics has been found in the eastern JINKA 1:100 000 Sheet (135.87582°E, 22.63157°S; 590000mE, 7497000mN).|16-MAY-23
28387|Bonya Metamorphics|General description|The Bonya Metamorphics occur wide-spread in the central part of the 1:100 000 Jervois Range map sheet in the Jervois mineral field and Bonya Hills areas. In these areas the Bonya Metamorphics are the only metasedimentary rocks exposed. The informal subunits occur interlayered in the metre- to 100 metre scale, the porphyroblastic schists and mica schists are the most common in the Bonya Hills and the Jervois mineral field area. Variations occur in abundance of calc-silicate rocks (more abundant in the Bonya Hills), mica-bearing metasandstone (more abundant in the Jervois mineral field), and garnet schists, quartz magnetite-hematite rocks and tourmalinites have only been identified in the Jervois mineral field.|16-MAY-23
28387|Bonya Metamorphics|Thickness range|Sub-unit thicknesses range from decimetre- to 100 m-scale and lateral changes are common. In the type localities, the apparent thickness of the succession is in the 100 m- to 1000 m-scale. The thickness of original sedimentary units, or their stratigraphic order and an absolute younging direction could not be determined because of structural and metamorphic overprint. Thickness variations unknown due to abundant isoclinal folding. Apparent maximum thickness is 1-5 km. Apparent minimum thickness is decimetre. Average apparent thickness and typical regional variation is in the m¿km-scale.|16-MAY-23
28387|Bonya Metamorphics|Lithology|Porphyroblastic schists consist of interlayered: Medium- to fine-grained muscovite+/-biotite+/-plagioclase+/-K-feldspar+/-cordierite+/-andalusite schist with sub-mm- to cm-sized cordierite, andalusite, biotite, and/or K-feldspar porphyroblasts; minor fine-grained biotite-muscovite-cordierite-garnet schist; minor muscovite-biotite-cordierite-tourmaline schist with mm-sized tourmaline. Mica schists consist of interlayered: Fine- to coarse-grained, equigranular, partly chloritic biotite+/-muscovite+/-plagioclase+/-quartz schist; muscovite schist; very fine-grained, laminated quartz-muscovite-biotite meta-siltstone; and calcareous meta-mudstone. Calc-silicate rocks consist of: Compositionally layered para-amphibolite with mm- to cm-layers alternating between hornblende-rich and plagioclase-rich. Layers are microcrystalline to fine-grained, dynamically recrystallised calcic hornblende, plagioclase, quartz, calcite, clinopyroxene, K-feldspar, epidote, and biotite; massive impure marbles comprising calcite with minor dolomite, quartz, plagioclase, and garnet. Mica-bearing metasandstones consist of: Bright-grey layers of fine-grained, equigranular quartzite, locally with mm-layers of epidote, or magnetite/hematite; very fine- to medium-grained muscovite/sericite- or biotite-rich, schistose metasandstone; cm-layered, fine-grained quartz-muscovite+/-feldspar-biotite metasandstone schist; minor layered, equigranular quartz-rich rocks with variably abundant, up to cm-sized quartz and minor feldspar porphyroclasts (including meta-porphyries). Garnet schists consist of: Medium- to fine-grained quartz-rich garnet-muscovite schist; garnet-chlorite-quartz schist; garnet-cordierite schist with variably developed, euhedral garnet from <5 mm to 3 cm in diameter. Locally interpreted as meta-exhalites. Quartz-magnetite-hematite rocks and tourmalinites consist of: mm- to cm-wide, continuous and discontinuous compositional layering of alternating microcrystalline garnet-epidote-quartz layers and fine-grained to microcrystalline magnetite±quartz layers, with minor muscovite, hematite and tourmaline. Magnetite is commonly oxidised to hematite. Minor tourmalinites comprising irregular, mm- to cm-scale alternating quartz-rich and tourmaline-rich layers with minor muscovite, feldspar, apatite, and magnetite.|16-MAY-23
28387|Bonya Metamorphics|Depositional environment|Based on the presence of siliciclastic meta-sedimentary rocks interlayered with meta-carbonate rocks, a shallow marine or lacustrine water depositional environment is interpreted for the protoliths of the Bonya Metamorphics succession. Metamorphosed synsedimentary base metal mineralisation and metaexhalites in the Jervois mineral field are interpreted to have formed at or near the sediment-water interface as a Broken Hill-type mineral system (McGloin et al. in review). Boron isotope measurements of tourmaline in stratabound tourmalinites within the Bonya Metamorphics indicate a terrestrial (non-marine) boron source (McGloin et al. in review). Syn-depositional intrusion of bimodal igneous rocks yield a geochemical signature consistent with intrusion into a possibly-continental back-arc basin setting, supported by a stage of contemporaneous extensional deformation during the earliest deformation (Weisheit et al. in review).|16-MAY-23
28387|Bonya Metamorphics|Relationships and boundaries|The Bonya Metamorphics are the oldest exposed unit in the 1:100 000 Jervois Range map. Underlying basement to the Bonya Metamorphics is unknown and not exposed. Intruded syn-depositionally and prior to regional deformation and metamorphism by layer-parallel (sill) and rarely cross-cutting (dyke) Mascotte Orthogneiss, White Violet Orthogneiss, Kings Legend Amphibolite, Attutra Metagabbro, and Unca Granite. Xenoliths of Bonya Metamorphics occur in Jervois Granodiorite, Jericho Granite, Thring Granite, and Jinka Granite. Contacts to the Xanten and Cappocks granodiorites are not exposed, but interpreted as intrusive. The Bonya Metamorphics are also intruded by sills and dykes of the Samarkand Pegmatite and undivided pegmatite.Unconformably overlain by and locally faulted contact with various units of the Georgina Basin.|16-MAY-23
28387|Bonya Metamorphics|Identifying features|The Bonya Metamorphics are the only metasedimentary rocks of the Aileron Province that are exposed in the 1:100 000 Jervois Range map. All other units in that area are interpreted and observed to either intrude into the Bonya Metamorphics, to have a faulted contact, or to unconformably overlay the unit.|16-MAY-23
28387|Bonya Metamorphics|Structure and Metamorphism|Several ductile (Palaeoproterozoic) and brittle (Palaeozoic) deformation events including isoclinal folding with axial planar foliation (grain shape foliation, schistosity, compositional layering) and overprinting asymmetric, close to tight folding in the m- to 10m-scale with local development of crenulation and axial planar schistosity (eg Weisheit et al. 2015, 2016). Minor brittle fault movements occurred locally along pre-existing structures. Amphibolite facies conditions of up to 560-650 °C, 0.3-0.45 GPa during tectonothermal event between ca 1.79 and 1.71 Ga (Reno et al. 2015, 2017).|16-MAY-23
28387|Bonya Metamorphics|Age reasons|Deposition of the Bonya Metamorphics occurred between ca 1855 Ma (maximum depositional age) to ca 1786 Ma (minimum depositional age). Maximum depositional ages (Kositcin et al. 2015): A calc-silicate rock yielded a maximum depositional age of 1855 +/- 8 Ma (207Pb/206Pb SHRIMP zircon). This calc-silicate rock is interlayered with clastic meta-sandstone yielding a maximum depositional age of 1807 +/- 21 Ma (207Pb/206Pb SHRIMP zircon).  A porphyroblastic schist yielded a maximum depositional age of 1787 +/- 6 Ma (207Pb/206Pb SHRIMP zircon). Minimum depositional ages based on intrusive relationships with: Mascotte Orthogneiss (1789+/-3 Ma; 207Pb/206Pb SHRIMP zircon; Kositcin et al. 2011), White Violet Orthogneiss (1794+/-6 Ma; 207Pb/206Pb SHRIMP zircon; Kositcin et al. 2014), Attuttra Metagabbro (1786+/-4, 207Pb/206Pb SHRIMP zircon, Claoué-Long and Hoatson 2005).|16-MAY-23
28387|Bonya Metamorphics|Correlations|Possibly age equivalent to other metasedimentary rocks in the northeastern Aileron Province: Deep Bore Metamorphics: maximum depositional ages: 1822 +/- 9 Ma (Reno et al. 2018), 1805 +/- 7 Ma (Scrimgeour and Raith 2001), 1791 +/- 6 Ma (Kositcin et al. 2018a), 1769 +/- 25 Ma (Kositcin et al. 2018b). Cackleberry Metamorphics: minimum depositional age based on igneous crystallisation age of an unnamed biotite granite of 1805 +/- 4 Ma (Kositcin et al. 2011). Perenti Metamorphics:  minimum depositional age based on igneous crystallisation age of intruding Dneiper Granite (1771 +/- 6 Ma, Zhao and Bennett 1995)  and Mount Swan Granite (1713 +/- 7 Ma, Zhao and Bennett 1995). Kanandra Metamorphics: maximum depositional age 1804 +/- 10 Ma (Beyer et al. 2013). Utopia Quartzite: maximum depositional age 1820 +/- 15 Ma (Hollis et al. 2010). Ledan Schist: maximum depositional age ca 1810 Ma (Reno pers comm).|16-MAY-23
28387|Bonya Metamorphics|Alteration and Mineralisation|Locally host to syngenetic polymetallic base metal mineralisation (Jervois mineral field; eg McGloin and Weisheit 2015, McGloin et al. 2016). In the vicinity of the mineralisation the Bonya Metamorphics are altered to massive garnetites and skarn development in calc-silicate rocks is common (eg Peters et al. 1985). Locally host to epigenetic Cu-W mineralisation in the Bonya Hills (eg Belbin 2015) and the Jervois mineral field (eg Mayes 2016). Toumalinisation occurs locally at the contact to tourmaline-bearing pegmatites and veins (eg Reith et al. 2004). K-feldspar and quartz alteration, silicification, and hematitisation is common close to major structures. All outcrops of Bonya Metamorphics are weathered, including the formation of regolith horizons.|16-MAY-23
28387|Bonya Metamorphics|Geophysical Expression|Characterised by a layer-like geomagnetic signal of magnetic low and high trends that follow lithological layers outcropping at the surface, indicating regional-scale folding and faulting. Elevated susceptibility compared to adjacent igneous units. Meta-carbonate rocks within the Bonya Metamorphics have a distinct magnetic moderate-low signal with rare high trends. (eg Whiting 1987).  The gravity signal is moderately high compared to the distinct low signals of adjacent felsic igneous rocks. Radiometric high signals derive from metamudstone and metasandstone outcrops.|16-MAY-23
28387|Bonya Metamorphics|Defn author|Anett Weisheit, Barry Reno, Eloise Beyer (Department of Primary Industry and Resources, Northern Territory Geological Survey) 17-SEP-2018.|16-MAY-23
28387|Bonya Metamorphics|References|1. Beyer EE, Hollis JA, Whelan JA, Glass LM, Donnellan N, Yaxley G, Armstrong R, Allen CM and Schersten A, 2013. Summary of results. NTGS laser ablation ICPMS and SHRIMP U-Pb, Hf and O geochronology project: Pine Creek Orogen, Arunta Region, Georgina Basin and McArthur Basin; July 2008-May 2011, Northern Territory Geological Survey Record, 2012-007, 205p.  **Belbin W, 2015. Targeting High Grade Copper at Bonya: in 'Annual Geoscience Exploration Seminar (AGES) 2015. Record of abstracts'. Northern Territory Geological Survey, Record 2015-002.  **Claoué-Long JC and Hoatson DM, 2005. Proterozoic mafic-ultramafic intrusions in the Arunta Region, central Australia. Part 2: event chronology and regional correlations. Precambrian Research 142, 134-158.  **Hollis JA, Beyer EE, Whelan JA, Kemp AIS, Schersten A and Greig A, 2010. Summary of results. NTGS laser U-Pb and Hf geochronology project: Pine Creek Orogen, Murphy Inlier, McArthur Basin and Arunta Region, July 2007-May 2008, Northern Territory Geological Survey Record, 2010-001, 142p.  **Kositcin N, Magee CW, Whelan JA and Champion DC, 2011. New SHRIMP geochronology from the Arunta Region: 2009-2010. Geoscience Australia, Record 2011/14.  **Kositcin N, Beyer EE and Whelan JA, 2014. Summary of results. Joint NTGS-GA SHRIMP geochronology project: Arunta Region, July 2013-June 2014. Northern Territory Geological Survey, Record 2014-008.  **Kositcin N, Reno BL and Whelan JA, 2015. Summary of results. Joint NTGS-GA geochronology project: Arunta Region, July 2014 - June 2015. Northern Territory Geological Survey, Record 2015-007.  **Kositcin N, Reno BL and Beyer EE, 2018a. Summary of results. Joint NTGS-GA geochronology project: Aileron Province, July 2015-June 2016. Northern Territory Geological Survey, Record 2018- 005.  **Kositcin N, McGloin MV, Reno BL, Weisheit A and Beyer EE, 2018b. Summary of results. Joint NTGS-GA geochronology project: Base metal and tungsten mineralisation, and skarn alteration in the Aileron Province, July 2017-June 2018. Northern Territory Geological Survey, Record 2018- 009.  **Maidment DW, Hand M and Williams IS, 2005. Tectonic cycles in the Strangways Metamorphic Complex, Arunta Inlier, central Australia: geochronological evidence for exhumation and basin formation between two high-grade metamorphic events, Australian Journal of Earth Sciences, 52(2), p205-215.  **Mayes K, 2016. Geophysical exploration and discovery at Jervois: in 'Annual Geoscience Exploration Seminar (AGES) Proceedings, Alice Springs, Northern Territory 15-16 March 2016'. Northern Territory Geological Survey, Darwin.  **McGloin M and Weisheit A, 2015. Base metal and tungsten mineralisation in the Jervois mineral field and Bonya Hills: characterisation, potential genetic models and exploration implications: in 'Annual Geoscience Exploration Seminar (AGES) 2015. Record of Abstracts'. Northern Territory Geological Survey, Record 2015-002.  **McGloin M, Maas R, Weisheit A, Meffre S, Thompson J, Zhukova I, Steward J, Hutchinson G, Trumbull R and Craser R, 2016. Palaeoproterozoic copper mineralisation in the Aileron Province: new findings on temporal, spatial and genetic features: in 'Annual Geoscience Exploration Seminar (AGES) Proceedings, Alice Springs, Northern Territory 15-16 March 2016'. Northern Territory Geological Survey, Darwin.  **McGloin MV, Weisheit A, Trumbull RB and Maas R, in review. Using tourmaline to indicate base metal and tungsten mineralising processes in the Jervois mineral field and Bonya Hills. Northern Territory Geological Survey, Darwin.  **Peters M, Kehrens P and van Gils H, 1985. Geology and Mineralisation of the Jervois Range, N.T., Australia, State University Utrecht.  **Raith JG, Riemer N and Meisel T, 2004. Boron metasomatism and behaviour of rare earth elements during formation of tourmaline rocks in the eastern Arunta Inlier, central Australia, Contributions to Mineralogy and Petrology, 147, 91-109.  **|16-MAY-23
28387|Bonya Metamorphics|References|2. Reno BL, Beyer EE, Weisheit A, Whelan JA, Kositcin N and Kraus S, 2015. Geological evolution of the Jervois Range 1:100.000 special map area: in 'Annual Geoscience Exploration Seminar (AGES) 2015. Record of Abstracts'. Northern Territory Geological Survey, Record 2015-002.  **Reno BL, Weisheit A, Beyer EE, McGloin MV and Kositcin N, 2017. Proterozoic tectonothermal evolution of the northeastern sector of the Aileron Province: in 'Annual Geoscience Exploration Seminar (AGES) 2017. Proceedings'. Northern Territory Geological Survey, Record 2017-002, 36-41.  **Reno BL, Beyer EE, Thompson JM and Meffre S, 2018a. NTGS laser ablation ICP¿MS zircon petrochronology project: Aileron Province, Jinka and Dneiper 1:100 000 mapsheets. Northern Territory Geological Survey, Record 2018-003.  **Scrimgeour IR and Raith J, 2001. Tectonic and thermal events in the northeastern Arunta Province. Northern Territory Geological Survey, Report 12.  **Shaw RD, Warren RG and Freeman MJ, 1985. Statigraphic definitions of named units in the Arunta Block, Northern Territory, 1979-82, Bureau of Mineral Resources, Australia, Report, 260.  **Stewart AJ, Shaw RD, Offe LA, Langworthy AP, Warren RG, Allen AR, and Clarke DB, 1980. Stratigraphic definitions of named units in the Arunta Block, Northern Territory, Bureau of Mineral Resources, Australia, Report, 216.  **Warren G and Thorpe R, 1994. Implications of Pb-isotope data for tectonostratigraphic correlations in the Proterozoic of central Australia, AGSO Research Newsletter, 20, p11-13.  **Warren RG, Thorpe RI, Dean JA and Mortensen JK, 1995. Pb-Isotope data from base-metal deposits in central Australia: Implications for Proterozoic stratigraphic correlations, AGSO Journal of Australian Geology and Geophysics, 15(4), p501-509.  **Weisheit A, Reno BL, Beyer EE and Whelan JA, 2015. Pulses of progressive shearing and reactivated fault structures: The 1.5 b.y. Palaeoproterozoic to Palaeozoic structural and metamorphic evolution of eastern Arunta Region, central Australia: in Siégel C, Verdel C, Rosenbaum G (editors). 'Riding the Wave: GSA Specialist Group in Tectonics and Structural Geology Conference, November 2015'. Geological Society of Australia Abstract 113, p 151.  **Weisheit A, Reno BL, Beyer EE, Whelan JA and McGloin M, 2016. Multiply reactivated crustal-scale structures and a long-lived counter-clockwise P-T path: New insights into the 1.5 billion year tectonothermal evolution of the eastern Arunta Region, central Australia: in 'Annual Geoscience Exploration Seminar (AGES) Proceedings, Alice Springs, Northern Territory 15¿16 March 2016'. Northern Territory Geological Survey, Darwin.  **Weisheit A, Reno BL and Beyer EE, in review. Jervois Range Special, Northern Territory. 1:100 000 geological map explanatory notes, 6152 and part 6252. Northern Territory Geological Survey, Darwin.  **Whiting TH, 1987. A study of the lithology and structure of the eastern Arunta Inlier based on aeromagnetic interpretation. PhD thesis, Department of Geology and Geophysics, University of Adelaide.  **Zhao JX and Bennett VC, 1995. SHRIMP U-Pb zircon geochronology of granites in the Arunta Inlier, central Australia: implications for Proterozoic crustal evolution. Precambrian Research 71, 17-43.|16-MAY-23
82055|Boomerang Formation|Name source|After Boomerang Creek, a seasonal meandering river channel in the Northern Territory that stretches from the Carrara Range (GDA 94 latitude 18degress40'50"S, longitude 137degrees44'00"E), where it hosts siliciclastic sedimentary rocks of the proposed Boomerang Formation, to the Barkly Tableland, where it links with Carrara Creek (GDA94 latitude 18degrees50'18"S, longitude 137degreeso48'18"E).|
82055|Boomerang Formation|Unit history|The Boomerang Formation is a new name to describe outcrop previously identified as Surprise Creek Formation in the MOUNT DRUMMOND 250K mapsheet in the Northern Territory (Rawlings et al, 2006, 2008). The Surprise Creek Formation is a siliciclastic sedimentary succession that was previously interpreted to stretch from Queensland into the Northern Territory. However, due to the large distance and lack of intervening outcrop between the type section in Queensland and the mapped exposures in MOUNT DRUMMOND, it is unclear whether the Surprise Creek Formation in Queensland is the same unit that outcrops in the Northern Territory. As a result of this uncertainty, and the lack of lithological similarity of the NT outcrops to any of the other siliciclastic units of the Carrara Range Group in this area, we have assigned exposures of the former Surprise Creek Formation in the Northern Territory to the new Boomerang Formation.|
82055|Boomerang Formation|Geomorphic expression|Forms ridges and local mesas throughout the Carrara Range.|
82055|Boomerang Formation|Type section locality|The type locality for the Boomerang Formation in MOUNT DRUMMOND is part of an existing type section for the defunct Musselbrook Formation, defined by Sweet et al (1984) as extending from 53K 760448 7938937 (137degrees28’7”E 18degrees37’29”S; base) to 53K 760389 7942299 (137degrees28’3”E 18degrees35’38”S; top). No new type section defined here. Unit reference area nominated in the vicinity of (GDA94) 18degrees37’24.7”E 137degrees24’57.9”S (Rawlings et al, 2008).|
82055|Boomerang Formation|Extent|The Boomerang Formation outcrops in the Carrara Range in MOUNT DRUMMOND, from Wild Cow Creek in the west (GDA 94 latitude 18degrees38'18"S, longitude 137degrees22'14"E) to Don Creek in the east (GDA 94 latitude 18degrees40'22"S, longitude 137degrees48'25"E).|
82055|Boomerang Formation|General description|Basal pebble to boulder conglomerate with clasts of quartz, quartzite and rhyolite in matrix of pink, medium- to coarse-grained sublithic sandstone; white to pink, thick- to very thick-bedded, medium- to coarse-grained, sublithic to quartz sandstone.|
82055|Boomerang Formation|Thickness range|The formation ranges from 300 m thick in the east, where there is no conglomerate, to 350–450 m in the central and western Carrara Range in MOUNT DRUMMOND. The thicker basal conglomerate beds, mapped out by Sweet et al (1984) as Pmb1a, range from 0 to 200 m-thick.|
82055|Boomerang Formation|Lithology|Consists of basal lenses and beds of pebble to boulder conglomerate, interbedded with and overlain by sublithic to quartz sandstone. The conglomerate consists of sub-rounded to rounded pebbles and cobbles, and scattered boulders of quartz, pink quartzite and quartz sandstone, set in a matrix of coarse-grained to granular lithic sandstone.|
82055|Boomerang Formation|Depositional environment|The basal conglomeratic rocks are proximal deposits, deposited in either a braided fluvial or alluvial fan setting. The sandstone component of the formation is probably a braided fluvial deposit, as it appears to grade up from the underlying conglomerates.|
82055|Boomerang Formation|Fossils|None.|
82055|Boomerang Formation|Relationships and boundaries|Unconformable between the underlying Top Rocky Rhyolite and overlying Drummond Formation of the Carrara Range Group.|
82055|Boomerang Formation|Identifying features|Basal pebble to boulder conglomerate. Base of the Boomerang Formation (formerly the Surprise Creek Formation) is a regional angular unconformity (Rawlings et al, 2008). The basal conglomeratic intervals of the Boomerang Formation are dominated by rhyolite clasts, with the proportion of rhyolite clasts to quartz clasts decreasing up section (Rawlings et al, 2008).|
82055|Boomerang Formation|Structure and Metamorphism|Extensively faulted and regionally folded.|
82055|Boomerang Formation|Age reasons|Maximum depositional ages derived from U-Pb SHRIMP dating of detrital zircons (Kositcin and Carson 2019):
1792 ± 13 Ma (GA sample number 2786178). 1743 ± 26 Ma (GA sample number 2786161). Magmatic crystallisation ages for the underlying Top Rocky Rhyolite of 1725 ± 3 Ma (Page et al 2000) further constrain the maximum depositional age for the Boomerang Formation to ca 1725 Ma.|
82055|Boomerang Formation|Correlations|The detrital zircon spectra for samples of the Boomerang Formation (Samples 2785623, 278616; Kositcin and Carson 2019), which was previously mapped by Rawlings et al (2006, 2008) as the ungrouped Surprise Creek formation, are comparable to Sample 2785622 of the Gator Sandstone. We propose that the Drummond Formation should be reattributed from the McNamara Group to the Carrara Range Group, despite the existence of multiple unconformities. The Boomerang Formation might be stratigraphically equivalent with the Surprise Creek Formation in Queensland.|
82055|Boomerang Formation|Alteration and Mineralisation|Mildly silicified.|
82055|Boomerang Formation|Geophysical Expression|Moderate to high magnetic response, possibly as a consequence of its stratigraphic proximity to highly magnetic volcanic units in the Carrara Range Group.|
82055|Boomerang Formation|Geochemistry|Geochemical datasets from Boomerang Formation are published in Carson et al (2020).|
82055|Boomerang Formation|Defn author|Jack Simmons, Ben Williams, Chris Carson, Charles Verdel (Northern Territory Geological Survey).  9-OCT-2020|
82055|Boomerang Formation|Comments|The definition of the Surprise Creek Formation should be retained for all outcrops mapped as such in Queensland. However, all outcrops of 'Surprise Creek Formation' in the Northern Territory should be redefined as Boomerang Formation. Standard series 1:250 000 sheet names are shown in upper case.|
82055|Boomerang Formation|References|Carson CJ, Jarrett AJM, Anderson JR, Champion DC and Henson PA, 2020. Exploring for the Future - Whole rock geochemistry data release of sedimentary and igneous rocks from the South Nicholson region, Northern Territory and Queensland Geoscience Australia, Record 2020/02.   **Carson, C. J., Kositcin, N., Anderson, J. R., and Henson, P. A. in prep. A revised Proterozoic tectono-stratigraphy of the South Nicholson region, Northern Territory, Australia  -  insights from SHRIMP U-Pb detrital zircon geochronology. Australian Journal of Earth Sciences  **Kositcin N and Carson CJ, 2019. New SHRIMP U-Pb zircon ages from the South Nicholson and Carrara Range regions, Northern Territory. Geoscience Australia, Record 2019/09.  **Page RW, Jackson MJ and Krassay AA, 2000. Constraining sequence stratigraphy in north Australian basins: SHRIMP U-Pb zircon geochronology between Mt Isa and McArthur River. Australian Journal of Earth Sciences 47(3), 431-459.  **Rawlings DJ, Sweet IP and Kruse PD, 2006. Mount Drummond, NT (Second Edition). 1:250 000 Geological Map, Sheet SE 53-12. Northern Territory Geological Survey, Darwin.  **Rawlings DJ, Sweet IP and Kruse PD, 2008. Mount Drummond, NT (Second Edition). 1:250 000 Geological Map Series Explanatory Notes, Sheet SE 53-12. Northern Territory Geological Survey, Darwin.  **Sweet IP, 1984. Carrara Range region, Northern Territory (First Edition). 1:100 000 geological map commentary, portions of 6360 and 6460. Bureau of Mineral Resources, Canberra.  **Sweet IP, Mond A and Stirzaker J, 1984. Carrara Range Region, Northern Territory. 1:100 000 Geological Map Series, Carrara 6460 and Mitchiebo 6360. Bureau of Mineral Resources (BMR).  **Carson, C. J., Kositcin, N., Anderson, J. R., and Henson, P. A. in prep. A revised Proterozoic tectono-stratigraphy of the South Nicholson region, Northern Territory, Australia - insights from SHRIMP U-Pb detrital zircon geochronology. Australian Journal of Earth Sciences.|
28156|Boothby Orthogneiss|Name source|Mount Boothby (5552-248019), northern part of Aileron 1:100 000 Sheet area.|16-MAY-23
28156|Boothby Orthogneiss|Type section locality|5552-270054, 1 km west of Prowse Gap, northern part of Aileron 1:100 000 Sheet area; ridge of well exposed augen gneiss with intrusive contact against Aileron metamorphics to north. A reference locality for the porphyritic granite variant is at 5552-260973, 5 km northwest of Aileron; hill shows clear exposures of flow-textured bands of granite alternating with bands of layered granulite of Aileron metamorphics.|16-MAY-23
28156|Boothby Orthogneiss|Extent|Northern part of Aileron 1:100 000 Sheet area; extends north in to southern edge of Tea Tree 1:100 000 Sheet area and east into western edge of Alcoota 1:250 000 Sheet area.|16-MAY-23
28156|Boothby Orthogneiss|Lithology|Coarse porphyroblastic granitic augen gneiss; small amount of porphyritic granite with euhedral phenocrysts. Augen and phenocrysts composed of microcline. Some small rapakivi feldspars also present. Normal granitic mineral assemblage, with sillimanite and garnet also in a few samples, and rarely andalusite.|16-MAY-23
28156|Boothby Orthogneiss|Relationships and boundaries|Intrudes Aileron metamorphics (q.v.), Nolans Dam metamorphics (q.v.), Weldon metamorphics, Tyson Creek granulite. Faulted against Napperby Gneiss.|16-MAY-23
28156|Boothby Orthogneiss|Identifying features|Reason for Proposed Name: Distinctive body of granitic gneiss, different in composition and texture from surrounding metamorphic rocks.|16-MAY-23
28156|Boothby Orthogneiss|Age reasons|L.P. Black (BMR, pers. Comm., 1977) has obtained preliminary Rb-Sr date of 1100 m.y. on Boothby Orthogneiss; late Middle Proterozoic.|16-MAY-23
28156|Boothby Orthogneiss|Proposed publication|Commentary on Reynolds Range-Aileron 1:100 000 Special Map|16-MAY-23
80341|Boundary Igneous Complex|Name source|Boundary Hill (656592mE 7484853mN; GDA94, Zone53) in western 1:250 000 TOBERMOREY mapsheet, Northern Territory|16-MAY-23
80341|Boundary Igneous Complex|Unit history|Eastern outcrops previously interpreted as Jervois Granite on the second edition 1:250 000 HUCKITTA mapsheet (Freeman et al 1986) and unnamed granite on the second edition 1:250 000 TOBERMORY mapsheet (Kruse et al 2002). Western outcrops in Bonya Hills not previously identified but possibly part of former Mascotte Gneiss Complex from the second edition 1:250 000 HUCKITTA mapsheet (Freeman et al 1986).|16-MAY-23
80341|Boundary Igneous Complex|Geomorphic expression|Bouldery rises and hillocks, scattered boulders, isolated low outcrops.|16-MAY-23
80341|Boundary Igneous Complex|Type section locality|(1) porphyritic biotite-bearing granite at 647592mE 7482441mN (GDA94, Zone53), access via the Plenty Highway; (2) leucogranite at 647604mE 7482459mN (GDA94, Zone53), access via the Plenty Highway; (3) biotite granodiorite at 611270mE 7482065mN (GDA94, Zone 53), access on foot.|16-MAY-23
80341|Boundary Igneous Complex|Extent|Scattered outcrops in 1:100 000 Jervois Range Special mapsheet: up to 7 km northwest to northeast of Mount Thring (606446mE 7476178mN; GDA95, Zone53), up to 10 km west to north of Mount Cornish Bore (648580mE 7478206mN), up to 8 km southwest to northwest of Boundary Hill (656592mE 7484853mN), about 10 km northeast of Coolibah Bore (645610mE 7466158mN).|16-MAY-23
80341|Boundary Igneous Complex|General description|Bouldery rises and hillocks of biotite granodiorite, and scattered boulders, isolated low outcrops of a variety of granites around the type localities; undeformed to moderately foliated; complex intrusive relationships between the igneous components of the complex are difficult to resolve because of  the generally poor exposure.|16-MAY-23
80341|Boundary Igneous Complex|Lithology|(1) porphyritic biotite-bearing granite: abundant <8 cm long K-feldspar phenocrysts in a fine- to medium-grained, inequigranular matrix of quartz-K-feldspar-plagioclase-biotite, 15% biotite, rare secondary muscovite; subordinate sparsely porphyritic variant; (2) leucogranite: fine- to medium-grained, equigranular to inequigranular assemblage of quartz-K-feldspar-plagioclase-biotite-muscovite, biotite-poor with <5% biotite; locally intruding (1); (3) biotite granodiorite: fine-to medium-grained inequigranular to equigranular quartz-plagioclase-K-feldspar-biotite, 10-15% biotite.|16-MAY-23
80341|Boundary Igneous Complex|Depositional environment|Continental margin environment, either arc cordillera or back arc basin, or derived from melting of pre-existing crust that formed in a continental margin environment.|16-MAY-23
80341|Boundary Igneous Complex|Relationships and boundaries|Contact relationships with other units not observed. Exact nature of unit boundary is not possible to define due to poorly exposed outcrop. Interpreted to intrude Thring Granite (contacts not exposed) and Jervois Granodiorite (xenoliths of the Jervois Granodiorite occur in leucogranite at 651466mE 7486605mN, GDA94, Zone53). Unconformably overlain by Mount Cornish Formaton of the Georgina Basin.|16-MAY-23
80341|Boundary Igneous Complex|Identifying features|Forms fresh bouldery outcrop on plains.|16-MAY-23
80341|Boundary Igneous Complex|Structure and Metamorphism|Undeformed to moderately foliated; weakly metamorphosed.|16-MAY-23
80341|Boundary Igneous Complex|Age reasons|(1) porphyritic biotite-bearing granite: magmatic crystallisation age of 1746±4 Ma (SHRIMP 207Pb/206Pb, Kositcin et all 2011); (2) leucogranite intruding the porphyritic granite: magmatic crystallisation age of 1753±4 Ma (SHRIMP 207Pb/206Pb, Cross et al 2005); (3) biotite granodiorite: magmatic crystallisation age of 1769 ± 14 Ma (LA¿ICP¿MS 207Pb/206Pb, Beyer et al 2018).|16-MAY-23
80341|Boundary Igneous Complex|Alteration and Mineralisation|Local sericitisation, secondary muscovite, chloritisation; no known mineralisation.|16-MAY-23
80341|Boundary Igneous Complex|Geophysical Expression|outcrops occur in magnetic low areas and varying gravity signals; outcrops too small and scattered to create a distinct radiometric signal.|16-MAY-23
80341|Boundary Igneous Complex|Geochemistry|I-type geochemistry; moderately to strongly peraluminous, calc-alkaline and low-K (tholeiitic) granodiorites; strongly metaluminous, high-K and shoshonitic monzogranites. Granodiorites characterised by moderate to high LREE enrichment, gently to moderately sloping HREE, and negative Eu anomalies. Monzogranites are characterised by enriched in LREE, have gently to moderately sloping HREE, and negative Eu anomalies.|16-MAY-23
80341|Boundary Igneous Complex|Defn author|Anett Weisheit, Barry Reno, Eloise Beyer (Department of Primary Industry and Resources, Northern Territory Geological Survey) 27-JUN-2018.|16-MAY-23
80341|Boundary Igneous Complex|References|Cross A, Claoué-Long JC, Scrimgeour IR, Ahmad M and Kruse PD 2005. Summary of results. Joint NTGS-GA geochronology project: Rum Jungle, basement to the Georgina Basin and eastern Arunta Region 2001-2003. Northern Territory Geological Survey Record 2005-006.  **Freeman MJ, Black LA, Offe LA, Senior BR, Shaw RD, Shergold JH, Simpson CJ, Walter MR, Warren RG, Donnellan N, Horsfall CJ, Laurie JR and Walley AM, 1986. Huckitta, Northern Territory (Second Edition). 1:250 000 geological map series, SF 53-11. Northern Territory Geological Survey, Darwin.  **Kositcin N, Magee CW, Whelan JA and Champion DC, 2011. New SHRIMP geochronology from the Arunta Region: 2009-2010. Geoscience Australia, Record 2011/14.  **Kruse PD, Brakel AT, Dunster JN and Duffett ML, 2002. Tobermory, Northern Territory (Second Edition). 1:250 000 geological map series explanatory notes, SF 53-12. Northern Territory Geological Survey, Darwin and Geoscience Australia, Canberra.|16-MAY-23
37730|Bowgan Sandstone|Name source|Bowgan Creek, in northwestern corner of MOUNT DRUMMOND. This creek appears on old 1:250 000-scale topographic and geological maps (Smith and Roberts 1963), but has been changed to Creswell Creek on new 1:250 000- and 1:100 000-scale topographic sheets. Name Bowgan Waterhole still used for a small waterbody on Creswell Creek in BRUNETTE DOWNS, at 18o6'S,136o15'E.|16-MAY-23
37730|Bowgan Sandstone|Unit history|Previously mapped within (ie not differentiated from) Constance Sandstone in First Edition MOUNT DRUMMOND (Smith and Roberts 1963).|16-MAY-23
37730|Bowgan Sandstone|Geomorphic expression|Mildly resistant and ridge forming with white phototones.|16-MAY-23
37730|Bowgan Sandstone|Type section locality|Narrow strike ridge at 17deg59'S, 137degE (705200mE 7999800mN) along Murphys Creek in Canyon Range, MOUNT DRUMMOND. Locality lies along main outcrop belt and is therefore most representative of formation, but difficult to access. In this area, Bowgan Sandstone overlies Buddycurrawa Volcanics of Benmara Group. Reference section: Narrow isolated strike ridge at 18deg5'S, 136deg56'E (712400mE 8009850mN) along Pandanus Creek in northern Canyon Range, MOUNT DRUMMOND. Outcrop adjacent to Benmara¿Wangalinji road and reasonably easy to access, but may not be representative of whole formation. At this locality, 50 m of Bowgan Sandstone overlies Breakfast Sandstone of Benmara Group, with basal lithified palaeoregolith.|16-MAY-23
37730|Bowgan Sandstone|Extent|Northwestern MOUNT DRUMMOND and southwestern CALVERT HILLS, in Canyon Range (name newly approved by Committee for Geographic Names in Australasia). Outcrop extends along north-northeasterly belt on eastern fringe of Canyon Range, from headwaters of Benmara Creek in south (695000mE 7982000mN in MOUNT DRUMMOND) to Pandanus Creek in north (705000mE 8012000mN in CALVERT HILLS).|16-MAY-23
37730|Bowgan Sandstone|Thickness range|Up to 100 m, but generally about 10 m.|16-MAY-23
37730|Bowgan Sandstone|Lithology|Maroon to pink or red-brown, variably ferruginous, lithic to sublithic, fine- to coarse-grained sandstone, with occasional laminae of quartz granules and small pebbles. In hand specimen, sandstone has notable `speckled¿ appearance, due to presence of white lithic fragments in pink ferruginous background. Unit medium to thickly bedded with planar bedding, a parting lineation, small-scale trough cross-beds and mudstone intraclasts. Subtle large bedforms may also be present. Chert pebbles and cobbles recognised near base at some localities (eg 702650mE 7992300mN). At 705200mE 8081800mN, a thin interval of polymict breccia is recognised at base of formation, comprising angular clasts of sandstone, claystone and ?chert in coarse-grained sandstone matrix.|16-MAY-23
37730|Bowgan Sandstone|Depositional environment|Braided fluvial to shallow-marine intertidal.|16-MAY-23
37730|Bowgan Sandstone|Relationships and boundaries|Parent units: Wild Cow Subgroup, South Nicholson Group. Unconformably overlies Murphy Metamorphics and Benmara Group. Base not exposed, but breccia with polymict clasts recognised at some localities. Contact either low-angle unconformity or layer-parallel fault. Latter could imply that Benmara and South Nicholson groups were once stratigraphically contiguous and conformable, and subsequently became structurally bound. Unconformity is favoured herein, based on consistent stratigraphic position of the discontinuity, and the different facies of the two groups (eg volcanic in Benmara Group but not in South Nicholson Group). Conformably overlain by Crow Formation, but contact not well exposed, due to recessive nature of rock types in transition zone. In most instances, contact marked by development of distinctive chert, secondary ironstone or clay-rich caliche, perhaps after sulfidic shale. At 701850E 7989650N, possible chertified digitate stromatolites are interbedded with white claystone and sandstone at contact.|16-MAY-23
37730|Bowgan Sandstone|Age reasons|Maximum age constrained only by underlying Cliffdale Volcanics basement (>1845 Ma; Page et al 2000). Immediately underlying Buddycurrawa Volcanics undated, but could potentially be in range 1725-1580 Ma. Minimum age is that of overlying late Neoproterozoic to Phanerozoic Georgina Basin. Based on correlation of South Nicholson Group with Roper Group, probable age range of 1500-1400 Ma can be proposed for South Nicholson Group, and hence for Bowgan Sandstone (Jackson et al 1999, Abbott et al 2001).|16-MAY-23
37730|Bowgan Sandstone|Correlations|Probably Playford Sandstone, which forms base of South Nicholson Group south and southeast of Benmara Fault in northwestern MOUNT DRUMMOND.|16-MAY-23
37730|Bowgan Sandstone|Defn author|Rawlings, D.J. [defn published 2008]|16-MAY-23
37730|Bowgan Sandstone|Comments|Age likely to be near older end of range for Roper Group (1500¿1400 Ma).|16-MAY-23
37730|Bowgan Sandstone|References|**ABBOTT S.T., Sweet I.P., Plumb K.A., Young D.N., Cutovinos A., Ferenczi P.A., Brakel A. and Pietsch B.A., 2001. Roper region: Urapunga and Roper River special, Northern Territory (Second Edition); 1:250 000 Geological Map Series, sheets SD53-10,11. Northern Territory Geological Survey-Australian Geological Survey Organisation (NGMA), Map and Explanatory Notes.  **JACKSON M.J., Sweet I.P., Page R.W. and Bradshaw B.E., 1999. The South Nicholson and Roper Groups: evidence for the early Proterozoic Roper Superbasin. In: Bradshaw B.E. and Scott D.L. (Eds.), Integrated basin analysis of the Isa Superbasin using seismic, well-log and geopotential data: an evaluation of the economic potential of the northern Lawn Hill Platform. Australian Geological Survey Organisation, Record 1999/19 (unpaginated).  **PAGE R.W., Jackson M.J. and Krassay A.A., 2000. Constraining sequence stratigraphy in north Australian basins: SHRIMP U-Pb zircon geochronology between Mt Isa and McArthur River. Australian Journal of Earth Sciences, 47, 3; 431-459.  **RAWLINGS D.J. Sweet I.P. and Kruse P.D., 2008. Mount Drummond, Northern Territory (Second Edition); 1:250 000 Geological Map Series, sheet SE53-12. Northern Territory Geological Survey, Map and Explanatory Notes.  **SMITH J.W. and Roberts H.G., 1963. Mount Drummond, N.T. (First Edition); 1:250,000 geological series, sheet SE53-12. Bureau of Mineral Resources, Geology and Geophysics, Map and Explanatory Notes.|16-MAY-23
84104|Boxer Member|Name source|Unit name derived from Boxer Creek, which flows through the western MOUNT DRUMMOND 1:250 000 mapsheet in the Northern Territory, and joins Fish Hole Creek at approximately (GDA94) 18°28’43”S 136°39’4”E.|
84104|Boxer Member|Unit history|Unit was mapped as an undivided part of the “Mullera Formation” in the First Edition MOUNT DRUMMOND 1:250 000 mapsheet (Smith and Roberts, 1963a, b).Unit was mapped as the “Tobacco Member” of the Crow Formation by Rawlings et al (2006, 2008) in the Second Edition MOUNT DRUMMOND 1:250 000 mapsheet.|
84104|Boxer Member|Geomorphic expression|The unit outcrops as a narrow, moderately resistant and banded strip in the Canyon Range area on the northwestern MOUNT DRUMMOND 1:250 000 mapsheet (Rawlings et al, 2008).|
84104|Boxer Member|Type section locality|There is no type locality nominated for this formation. A reference area is nominated in the northwestern MOUNT DRUMMOND 1:250 000 mapsheet, in the vicinity of (GDA94) 18°14’40”S 136°49’5”E (53K 692223mE 7981815mN).|
84104|Boxer Member|Extent|The Boxer Member outcrops in the northwestern MOUNT DRUMMOND 1:250 000 mapsheet (Canyon Range area) in the Northern Territory.|
84104|Boxer Member|Thickness range|Unit thickness varies between approximately 300 m and 500 m (Rawlings et al, 2008).|04-OCT-23
84104|Boxer Member|Lithology|The unit is predominantly a series of stacked sandstone units, mostly of the "shallow-water sandstone facies” of Rawlings et al (2008), interlayered with the “storm shelf facies”.  The shallow-water sandstone facies comprises white to red/brown/maroon, silicified, fine- to very coarse-grained quartzose to lithic sandstone, with local pebble trails and poorly sorted pebble-cobble conglomerate. Clasts consist of silicified sandstone, quartz, chert, quartzite and mudstone. Sandstone is locally ferruginous, micaceous to glauconitic. The storm shelf facies comprises flaggy white/fawn/red-brown/purple micaceous siltstone and fine- to medium-grained quartzose to sublithic (± micaceous) sandstone. Siltstone is locally ferruginous and contains minor beds of vuggy, mottled or spotted medium- to coarse-grained glauconitic sandstone. Sedimentary structures include planar, wavy and lenticular bedding, cross- and parallel-lamination, hummocky cross-stratification, and symmetric ripples.|
84104|Boxer Member|Depositional environment|Unit is interpreted as a shallow-water sandstone predominantly, with minor, more-fine-grained facies indicative of deposition in storm shelf conditions (Rawlings et al, 2008).|
84104|Boxer Member|Relationships and boundaries|The Boxer Member of the Mingabarri Formation conformably overlies the undivided lower sections of the parent Mingabarri Formation, and is conformably overlain by the Creswell Creek Formation.|
84104|Boxer Member|Identifying features|Outcrop has a distinctive, banded, white to pale-red brown appearance, and has a high background gamma ray signature (Rawlings et al, 2008).|
84104|Boxer Member|Age reasons|Maximum depositional ages derived from U-Pb SHRIMP dating of detrital zircons:
Creswell Creek Formation (stratigraphically overlies Boxer Member): GA sample 3305198 – 1625 ± 27 Ma (Kositcin et al, 2020).
Undivided Mingabarri Formation (stratigraphically underlies Boxer Member): GA sample 2785621 – 1649 ± 19 Ma (Kositcin and Carson, 2019).Therefore, the potential depositional age range for the Boxer Member can be considered to extend from ca. 1649 ± 19 Ma to 1625 ± 27 Ma.|
84104|Boxer Member|Correlations|The Boxer Member of the Mingabarri Formation, based on maximum depositional age estimates for the underlying and overlying units, can be correlated with the ungrouped Caulfield Formation and several formations of the McNamara Group, including the Shady Bore Quartzite, the Bullrush Conglomerate, the Plain Creek Formation, and the Lawn Hill Formation (Page et al, 2000; Kositcin and Carson, 2019). The Creswell Creek Formation may be correlative with components of the upper Glyde package to the lowermost Favenc package (Rawlings, 1999) of the McArthur Basin.|
84104|Boxer Member|Alteration and Mineralisation|Silicified in some areas (Rawlings et al, 2008).|
84104|Boxer Member|Geophysical Expression|Weak to moderate magnetic response.|
84104|Boxer Member|Defn author|Elliot Foley, Jack Simmons, Ben Williams, Charles Verdel (Northern Territory Geological Survey), Chris Carson (Geoscience Australia) 31-MAY-2023.|
84104|Boxer Member|Comments|Note: Standard series 1: 100 000 and 1: 250 000 mapsheet names are shown in uppercase.|
84104|Boxer Member|References|Carson, C. J., Kositcin, N., Anderson, J. R., and Henson, P. A. in prep. A revised Proterozoic tectono-stratigraphy of the South Nicholson region, Northern Territory, Australia - insights from SHRIMP U-Pb detrital zircon geochronology. Australian Journal of Earth Sciences. 
 **Kositcin N and Carson CJ, 2019. New SHRIMP U-Pb zircon ages from the South Nicholson and Carrara Range regions, Northern Territory. Geoscience Australia, Record 2019/09.  **Kositcin N, Carson CJ, Anderson JR, Doublier MP and Murr J, 2020. Exploring for the Future - New SHRIMP geochronology constraints on the basin evolution of the South Nicholson region. Geoscience Australia, Record 2020/025.  **Page RW, Jackson MJ and Krassay AA, 2000. Constraining sequence stratigraphy in north Australian basins: SHRIMP U-Pb zircon geochronology between Mt Isa and McArthur River. Australian Journal of Earth Sciences 47(3), 431-459.  **Rawlings DJ, 1999. Stratigraphic resolution of a multiphase intracratonic basin system: the McArthur Basin, northern Australia. Australian Journal of Earth Sciences 46(5), 703–723.  **Rawlings DJ, Sweet IP and Kruse PD, 2006. Mount Drummond, NT (Second Edition). 1:250 000 Geological Map, Sheet SE 53-12. Northern Territory Geological Survey, Darwin, Northern Territory.  **Rawlings DJ, Sweet IP and Kruse PD, 2008. Mount Drummond, NT (Second Edition). 1:250 000 Geological Map Series Explanatory Notes, Sheet SE 53-12. Northern Territory Geological Survey, Darwin, Northern Territory.  **Simmons JM, Williams B, Carson, C and Verdel C, 2023a. Mount Drummond, Northern Territory 1:250 000 Geological Map, Sheet SE 53-12 (Third Edition). Northern Territory Geological Survey, Darwin, Northern Territory.  **Simmons JM, Williams B, Carson, C and Verdel C, 2023b. Mount Drummond, Northern Territory 1:250 000 Geological Map Explanatory Notes, Sheet SE 53-12 (Third Edition). Northern Territory Geological Survey, Darwin, Northern Territory.  **Smith JW and Roberts HG, 1963a. Mount Drummond, NT (First Edition). 1:250 000 Geological Map Series Explanatory Notes, Sheet 53-12. Bureau of Mineral Resources, Canberra.  **Smith JW and Roberts HG, 1963b. Mount Drummond, NT (First Edition). 1:250 000 Geological Map Series, Sheet SE 53-12. Bureau of Mineral Resources, Canberra.|
2472|Bradshaw Complex|Name source|Port Bradshaw (~lat 12degrees 30'S, long.136degrees 45'E), south of Nhulunbuy in Arnhem Bay - Gove.|16-MAY-23
2472|Bradshaw Complex|Unit history|previously mapped as  Bradshaw Granite by Dunnet (1965). Defined as Bradshaw Complex by  Plumb and Roberts (1992). Redefinition is the result of rationalisation of component units.|16-MAY-23
2472|Bradshaw Complex|Constituents|Undivided Bradshaw Complex, Melville Bay Metamorphics and Drimmie Head Granite.|16-MAY-23
2472|Bradshaw Complex|Geomorphic expression|The main outcrop areas comprise rounded weathered tors and boulders, surrounded by low scrub.|16-MAY-23
2472|Bradshaw Complex|Type section locality|Type areas for constituent formations are presented in their respective formal definitions.|16-MAY-23
2472|Bradshaw Complex|Extent|Two northeast trending elongate belts beween Melville Bay and Grays Bay in Arnhem Bay - Gove, covering an area of approximately 50 by 80 km.|16-MAY-23
2472|Bradshaw Complex|Lithology|Pelitic, calcsilicate, psammitic and mafic gneiss, ranging from lower amphibolite to granulite facies; migmatiitic gneiss; granitic gneiss; garnetiferous granite and leucogranite.|16-MAY-23
2472|Bradshaw Complex|Relationships and boundaries|Overlain by Early Cretaceous siliciclastic rocks, Cainozoic and Quaternary coastal sediments and alluvium. Intruded by younger (~1840) Orosirian granites.|16-MAY-23
2472|Bradshaw Complex|Age reasons|The combined age of this formation, from analysis of single zircon grains by SHRIMP U-Pb geochronological techniques is ~1870 Ma (Page, pers. comm., 1995).|16-MAY-23
2472|Bradshaw Complex|Correlations|The Bradshaw  Complex is interpreted as  an inhomogeneously melted portion of a metamorphosed sedimentary protolith. Broad correlation with the Nimbuwah and Mirarrmina Complexes and high-grade metamorphic portions of the Pine Creek Inlier.|16-MAY-23
2472|Bradshaw Complex|Defn author|T. L. Madigan and D.J. Rawlings, 1997 (after Dunnet, 1965; Plumb and Roberts, 1992).|16-MAY-23
79781|Breaden Formation|Name source|Mount Breaden (133.0379deg E,  -24.6128deg S)|16-MAY-23
79781|Breaden Formation|Unit history|Part of former Winnall Beds Ranford et al (1965), Winnall beds (various authors) now redefined as Winnall Group.|16-MAY-23
79781|Breaden Formation|Geomorphic expression|Recessive, although typically deeply weathered and capped with ferricrete or silcrete.|16-MAY-23
79781|Breaden Formation|Type section locality|Around GDA94 53J 309702mE 7247490mN (133.1163deg E, -24.8579deg S) in along the axis of the Mill Ridge anticline in southeastern HENBURY 1:250 000 within HENBURY 1:100 000.|16-MAY-23
79781|Breaden Formation|Extent|Currently mapped in HENBURY 1:100 000, further extent unknown.|16-MAY-23
79781|Breaden Formation|General description|Probable cyclical association of red-brown and black (now white/leached where exposed) siltstones. May be in part calcareous. Generally recessive or where outcropping deeply weathered.|16-MAY-23
79781|Breaden Formation|Thickness range|Locally faulted and vertically dipping, the base is not exposed at the type locality which makes it difficult to estimate thickness. Thickness estimated to be a at least 70-100m to the west-northwest of Mount Breaden (133.0379deg E, -24.6128deg S) where it overlies Limbla Member or Aralka Formation and underlies Gloaming Formation.|16-MAY-23
79781|Breaden Formation|Lithology|Siltstone: thinly- and planar-bedded, or ripple cross-stratified. Chocolate-brown / dark red-brown but weathering orange, pinkish or white/pale cream. Locally chertifed to form finely banded 'ribbon-like' chert. Typically deeply weathered and capped with ferricrete or silcrete.|16-MAY-23
79781|Breaden Formation|Depositional environment|Probably shallow marine and variably red bed to darker-coloured and more organic-rich.|16-MAY-23
79781|Breaden Formation|Diastems or hiatuses|Unknown.|16-MAY-23
79781|Breaden Formation|Relationships and boundaries|Conformable with overlying Gloaming Formation, base not exposed but is an inferred unconformity with the Inindia beds.|16-MAY-23
79781|Breaden Formation|Identifying features|Contrasts with the thinly- to medium-bedded sandstones of the overlying Gloaming Formation that are characterised by abundant sedimentary structures (eg a variety of ripple types and cross-stratification).|16-MAY-23
79781|Breaden Formation|Structure and Metamorphism|Folded and faulted but apparently unmetamorphosed.|16-MAY-23
79781|Breaden Formation|Age reasons|Neoproterozoic and probably Ediacaran as it overlies the Pioneer Sandstone that locally represents the ca 640 Ma Elatina Glaciation and is overlain by rare probable Ediacaran fossil-bearing sandstones of the Winnall Group.|16-MAY-23
79781|Breaden Formation|Correlations|Probably correlates in part with Pertatataka Formation.|16-MAY-23
79781|Breaden Formation|Geophysical Expression|Generally linear, low total magnetic intensity typical of Winnall Group.|16-MAY-23
79781|Breaden Formation|Defn author|N Donnellan and VJ Normington, 28-Feb-2017.|16-MAY-23
79781|Breaden Formation|References|Ranford LC, Cook PJ and Wells AT, 1965. The geology of the central part of the Amadeus Basin, Northern Territory. Bureau of Mineral Resources, Australia, Report 86.|16-MAY-23
37732|Breakfast Sandstone|Name source|Breakfast Creek, around latitude 18o20'S longitude 137o00'E, a tributary to Buddycurrawa Creek in MOUNT DRUMMOND.|16-MAY-23
37732|Breakfast Sandstone|Unit history|Previously mapped within (ie not differentiated from) the 'Benmara beds' on the first edition of MOUNT DRUMMOND by Smith and Roberts (1963). Breakfast Sandstone was also partly mismapped as Constance Sandstone by the same authors.|16-MAY-23
37732|Breakfast Sandstone|Geomorphic expression|Mildly to strongly resistant and ridge forming with white banded phototones.|16-MAY-23
37732|Breakfast Sandstone|Type section locality|Strike ridge along small hill at latitude 18o9'S longitude 136o55'E in the headwaters of Whiterock Creek (newly approved by place names committee) in the Canyon Range in MOUNT DRUMMOND. Section runs from 703850E 7992050N (lower boundary) to 703500E 7991950N (upper boundary). At this section, 60 m of Breakfast Sandstone overlies Murphy Metamorphics.|16-MAY-23
37732|Breakfast Sandstone|Extent|Northwestern corner of MOUNT DRUMMOND and southwestern corner of CALVERT HILLS, in the Canyon Range (name newly approved by place names committee).|16-MAY-23
37732|Breakfast Sandstone|Thickness range|Up to 80 m.|16-MAY-23
37732|Breakfast Sandstone|Lithology|Comprises a resistant, banded strike ridge of white to maroon or pink, medium+/-coarse grained silicified sublithic sandstone. The lower few metres contains abundant quartz pebbles and lesser cobbles. The sequence tends to fine upwards, with small-scale (dm wavelength) trough cross-beds, planar bedding, symmetrical ripples, desiccation cracks and current lineation becoming increasingly common. Otherwise, it is medium- to thick-bedded with mudclasts, scattered quartz granules and small pebbles, and white angular silicified mudstone ('chert') clasts up to 5 cm diameter. The unit also contains rare laminae or thin beds of chertified mudstone and chertified carbonate with relict domal stromatolites. The depositional setting is interpreted to have been moderate to high energy braided fluvial and/or shallow marine.|16-MAY-23
37732|Breakfast Sandstone|Relationships and boundaries|Unconformably overlies Murphy Metamorphics and Connellys Volcanics. The base is rarely exposed, but at some localities the lower few metres contains abundant vein quartz pebbles, where it sits on the extensively quartz-veined Murphy Metamorphics. Conformably overlain by Buddycurrawa Volcanics, the boundary marked by a transition from relatively well-sorted quartzose sandstone into poorly-sorted ferruginous sandstone and ironstone. Parent unit: Benmara Group.|16-MAY-23
37732|Breakfast Sandstone|Age reasons|Constrained only by the underlying Cliffdale Volcanics basement (>1845 Ma; Page et al 2000) and overlying South Nicholson Group (maximum age ~1500 Ma; by correlation with Roper Group; Jackson et al 1999, Abbott et al 2001). Unable to date the conformably overlying Buddycurrawa Volcanics, which could potentially be in the range 1725 to 1580 Ma (Rawlings et al in prep).|16-MAY-23
37732|Breakfast Sandstone|Correlations|Uncertain.|16-MAY-23
37732|Breakfast Sandstone|Defn author|Rawlings, D.J. [approved 11-APR-2005]|16-MAY-23
37732|Breakfast Sandstone|Comments|Reference area: Area 1: Strike ridge along crest of small hill at 707300E 8000700N in the headwaters of Murphy's Creek in the Canyon Range in MOUNT DRUMMOND. At this locality, 80 m of Breakfast Sandstone overlies Murphy Metamorphics. Area 2: Narrow isolated strike ridge at latitude 18o5'S longitude 136o56'E (712400E 8009850N) along Pandanus Creek in the northern Canyon Range in MOUNT DRUMMOND. This outcrop is adjacent to the Benmara-Wangalinji road and reasonably easy to access. However, it is not representative of the formation. At this locality, 15 m of Breakfast Sandstone overlies Connellys Volcanics, but the base is not exposed. It is apparently overlain by Bowgan Sandstone of the South Nicholson Group (also a reference area). Note: All locations are based on the GDA94 geodetic datum. Standard series 1:250 000 sheet names are shown in upper case.|16-MAY-23
37732|Breakfast Sandstone|References|ABBOTT S.T., Sweet I.P., Plumb K.A., Young D.N., Cutovinos A., Ferenczi P.A., Brakel A. and Pietsch B.A., 2001. Roper region: Urapunga and Roper River special, Northern Territory (Second Edition); 1:250 000 Geological Map Series, sheets SD53-10,11. Northern Territory Geological Survey-Australian Geological Survey Organisation (NGMA), Map and Explanatory Notes.  **JACKSON M.J., Sweet I.P., Page R.W. and Bradshaw B.E., 1999. The South Nicholson and Roper Groups: evidence for the early Proterozoic Roper Superbasin. In: Bradshaw B.E. and Scott D.L. (Eds.), Integrated basin analysis of the Isa Superbasin using seismic, well-log and geopotential data: an evaluation of the economic potential of the northern Lawn Hill Platform. Australian Geological Survey Organisation, Record 1999/19 (unpaginated).  **PAGE R.W., Jackson M.J. and Krassay A.A., 2000. Constraining sequence stratigraphy in north Australian basins: SHRIMP U-Pb zircon geochronology between Mt Isa and McArthur River. Australian Journal of Earth Sciences, 47, 3; 431-459.  **RAWLINGS D.J. Sweet I.P. and Kruse P.D., in prep.[2008] Mount Drummond, Northern Territory (Second Edition); 1:250 000 Geological Map Series, sheet SE53-12. Northern Territory Geological Survey, Map and Explanatory Notes.  **SMITH J.W. and Roberts H.G., 1963. Mount Drummond, N.T. (First Edition); 1:250,000 geological series, sheet SE53-12. Bureau of Mineral Resources, Geology and Geophysics, Map and Explanatory Notes.|16-MAY-23
78970|Briggs Member|Name source|Good  exposures at Mount Briggs and in adjacent Daly River at 13.912130oS, 131.164417oE (MGA94 Zone 52: 733875mE, 8460929mN).|16-MAY-23
78970|Briggs Member|Unit history|None. New name.|16-MAY-23
78970|Briggs Member|Geomorphic expression|Restricted exposure due to widespread cover of Cretaceous rocks. Exposures form low hills with karst features, including pavements, caves, dolines, karren and kamenitza.|16-MAY-23
78970|Briggs Member|Type section locality|109.8-243.9 m depth in cored drillhole NTGS86/1, drilled at 14o09'50"S, 131o23'50"E (MGA94 Zone 52: 758890mE 8432980mN). Core stored at Northern Territory Geological Survey Core Library, Darwin.|16-MAY-23
78970|Briggs Member|Description at type locality|Fine to medium, crystalline pink-grey dolostone, ooid dolograinstone, stromatolitic doloboundstone, microbial dololaminite, fine-grained quartz dolostone and dolomitic quartz sandstone; minor intraformational flat-pebble breccia, quartz sandstone, and silty and shaly dolostone.|16-MAY-23
78970|Briggs Member|Extent|Area bounded by latitudes 13.771°S and 14.867°S and longitudes131.137°E and 132.228°E in central Daly Basin, extending a length of some 165 km northwest to southeast, with width about 39 km. Daly River transects this area.|16-MAY-23
78970|Briggs Member|Thickness range|134.1 m in type section; maximum recorded thickness 160.9 m 93km to the south east in waterbore RN7838 (MGA94 Zone 52: 183333mE 8371634mN) located close to Victoria Highway crossing of King River.|16-MAY-23
78970|Briggs Member|Depositional environment|Shallow marine above fair-weather wave base and subject to tidal currents; moderate energy conditions, eg offshore ooid shoals. Relatively remote from major sources of siliciclastic sediment; siliciclastic input decreased with time.|16-MAY-23
78970|Briggs Member|Fossils|None recorded.|16-MAY-23
78970|Briggs Member|Diastems or hiatuses|Numerous erosive surfaces are present but probably only of local extent.|16-MAY-23
78970|Briggs Member|Relationships and boundaries|Contact with underlying Jinduckin Formation conformable and transitional. Conformably overlain by King Member of Oolloo Dolostone. Boundary in type section marked by stromatolites overlying eroded surface on ooid dolograinstone; eroded surface considered to be a local feature probably not representing major time break. Rocks above contact are generally massive, whereas those below are well bedded. Neither contact exposed.|16-MAY-23
78970|Briggs Member|Identifying features|Characterised by finely crystalline dolomitic textures, well defined bedding, and common occurrence of ooids, which distinguish it from overlying King Member. Underlying Jinduckin Formation distinguished by being darker in colour and by presence of abundant dolomitic sandstone-siltstone.|16-MAY-23
78970|Briggs Member|Structure and Metamorphism|Flat lying to gently dipping towards the centre of the basin.|16-MAY-23
78970|Briggs Member|Age reasons|Unfossiliferous, but age broadly constrained by early middle Cambrian Tindall Limestone below and Early Ordovician Florina Formation above. Middle Cambrian age is considered most likely from presence of generally conformable contacts between units of Daly River Group, the lower part of which is securely dated as middle Cambrian, and from broad lithological correlations with Georgina Basin middle Cambrian succession.|16-MAY-23
78970|Briggs Member|Correlations|Camooweal Dolostone and possibly also Ranken Limestone of central Georgina Basin, based on lithological correlation of underlying Jinduckin Formation with Wonarah Formation of that region.|16-MAY-23
78970|Briggs Member|Alteration and Mineralisation|None recorded.|16-MAY-23
78970|Briggs Member|Geophysical Expression|Down-hole gamma log signature is typically noisy, and shows a cyclic pattern of more or less regularly spaced, thin shale intervals (higher gamma counts) at about 20 m intervals, separating thicker packages of dolostone. Main shale intervals can be correlated with moderate confidence between boreholes across extent of formation; many others are discontinuous and difficult to trace.|16-MAY-23
78970|Briggs Member|Geochemistry|Several major element and rare earth element analyses available (Tickell 2011[b?])|16-MAY-23
78970|Briggs Member|Defn author|Steven J Tickell, 3-OCT-2014|16-MAY-23
78970|Briggs Member|Comments|As a result of a relog of cored drillhole NTGS 86/1, the contact between the newly defined Daly Basin units, Briggs and King members (of the Oolloo Dolostone) has been changed (very slightly) for both type sections.  Tim Munson 23-APR-2015|16-MAY-23
78970|Briggs Member|References|Tickell SJ, 2002. Groundwater resources of the Oolloo Dolostone. Natural Resources Division, Northern Territory Department of Infrastructure, Planning and Environment, Technical Report 17/2002.***Tickell SJ, 2011a. Oolloo aquifer, 1:250,000 scale hydrogeological map. Natural Resources Division, Northern Territory Department of Infrastructure, Planning and Environment.***Tickell SJ, 2011b. Subsurface characteristics of the Oolloo Dolostone Natural Resources Division, Northern Territory Department of Infrastructure, Planning and Environment, Technical Report 28/2011.|16-MAY-23
21329|Brinkley Bluff Gneiss|Name source|Brinkley Bluff 133o23'E 23o43'S.|16-MAY-23
21329|Brinkley Bluff Gneiss|Unit history|Previously mapped as possible Burt Bluff Gneiss (Offe, 1981).|16-MAY-23
21329|Brinkley Bluff Gneiss|Geomorphic expression|Rubble-covered low hills.|16-MAY-23
21329|Brinkley Bluff Gneiss|Type section locality|South of the Waterhole beneath Brinkley Bluff near GR 334200 7376500 MacDonnell Ranges 1:100 000 Sheet area.|16-MAY-23
21329|Brinkley Bluff Gneiss|Extent|Crops out in the vicinity of Brinkley Bluff and along the northern Chewings Range as far west as Lovely Hill.|16-MAY-23
21329|Brinkley Bluff Gneiss|Lithology|Megacrystic granitic gneiss.|16-MAY-23
21329|Brinkley Bluff Gneiss|Relationships and boundaries|Intrudes Lovely Hill Schist, overlain by Chewings Range Quartzite, probably unconformably.|16-MAY-23
21329|Brinkley Bluff Gneiss|Structure and Metamorphism|Generally strongly foliated but locally only weakly foliated. Interleaved with the Chewings Range Quartzite as a result of thrusting (D2) of Chewings Orogeny. Metamorphosed at amphibolite facies.|16-MAY-23
21329|Brinkley Bluff Gneiss|Age reasons|Middle Proterozoic, younger than 1670 Ma (Age of Glen Helen Metamorphics in the Madderns Yard Metamorphic Complex, which underlies the Lovely Hill Schist), older than 1590 Ma (Age of metamorphism which affected the Iwupataka Metamorphic Complex).|16-MAY-23
21329|Brinkley Bluff Gneiss|Defn author|R.D. Shaw, 22 May 1991.|16-MAY-23
21329|Brinkley Bluff Gneiss|Comments|This 'definition' is missing the details of references mentioned in the synonymy and age, and shows no signs on the card of having been approved.|16-MAY-23
21342|Brumbreu Formation|Name source|Brumbreu Waterhole, lat. 19deg16'00"S, long.134deg52'12"E  (GR MU421695).|16-MAY-23
21342|Brumbreu Formation|Unit history|In large part equivalent to unit Ew4 of former Warramunga Group of Mendum and Tonkin (1976) and Mendum et al. (1978).|16-MAY-23
21342|Brumbreu Formation|Geomorphic expression|Low, rubbly and ferruginised rises and upstanding ridges flanking main Short and Whittington Ranges. Best exposures are to the west on SHORT RANGE where unit forms upstanding, rounded strike ridges separated by narrow recessive valleys of less resistant strata marking start of Short Range.|16-MAY-23
21342|Brumbreu Formation|Type section locality|From lat. 19deg19'19"S, long. 133deg55'00"E (GR LU862632) (base) for 900 m-updip to lat. 19deg18'38"S,  long. 133°55'21"E  (GR LU868644). Base of type section is a reference boundary stratotype. It is a sharp contact between deeply weathered, intermediate volcanic rocks of Wundirgi Formation and thin-bedded, fine-grained Brumbreu Formation sandstone.|16-MAY-23
21342|Brumbreu Formation|Extent|Crops out discontinuously on southern margin of Short Range and Whittington Range on SHORT RANGE and FLYNN, to east and west of Stuart Highway between Phillip Creek and Hayward Creek, and at base of low rises to north of Whippet Hill trigonometric station.|16-MAY-23
21342|Brumbreu Formation|Thickness range|About 900 m in type section.  A thickness of ~1450 m was measured by Mendum and Tonkin (1976) to north of Last Hope, but this is likely to involve fault repetition.|16-MAY-23
21342|Brumbreu Formation|Lithology|Lithic arenite, volcanic litharenite; magnetite/ heavy mineral-bearing quartz arenite; granule- and pebble-bearing sandstone; felsic tuff;  chert  (including a distinctive green variety which is silicified tuff and is a good marker horizon); and shale.|16-MAY-23
21342|Brumbreu Formation|Depositional environment|Marginal marine at base to fluviatile towards top. Detritus includes vitric and lithic tuff fragments suggesting epiclastic sedimentation, at least in part.|16-MAY-23
21342|Brumbreu Formation|Relationships and boundaries|Conformable basal contact with underlying Wundirgi Formation and transitional or locally erosional contact (e.g., lat. 19deg23'50"S,  long. 134deg09'46"E;   GR MU121855) with overlying Hayward Creek Formation. Contact between Brumbreu Formation and Hayward Creek Formation is often faulted (e.g., lat. 19deg53'07"S, long. 14deg09'58"E; GR MU127801). Local angular discordance between Wundirgi and Brumbreu Formations is attributed to disharmonic folding and not to regional unconformity. Intruded by diorite or dolerite. Conformably overlies Bernborough Formation. Top boundary stratotype: Transitional contact with  Hayward Creek Formation (first cobble conglomerate, as opposed to granule or pebble bed marking the onset of Hayward Creek Formation) at lat. 19deg18'38"S, long.  133deg55'21"E (GR LU868644 ). Bottom boundary stratotype: Sharp contact between thinly- bedded and rippled sandstone and siltstone of Wundirgi Formation and grey-green, indurated, medium- to thick-bedded and cross-bedded sandstone at base of the Brumbreu Formation at lat. 19deg07'17"S, long. 134deg09'50"E (GR MU863658).|16-MAY-23
21342|Brumbreu Formation|Structure and Metamorphism|Moderate to locally steeply  dipping, and folded into broad, open domes and basins with Tomkinson Creek Subgroup. Faulted. Local mesoscopic box folds (e.g., lat. 19deg53'07"S, long. 134deg09'27E; GR MU118801).|16-MAY-23
21342|Brumbreu Formation|Age reasons|Palaeoproterozoic. Conformably underlying Bernborough Formation is dated at 1833+/-4 Ma (Compston 1991) by U-Pb on zircon by ion microprobe; and revised to 1840+/-8 Ma and 1845+/-4 Ma by Compston  (1994).|16-MAY-23
21342|Brumbreu Formation|Correlations|Correlated  with Ooradidgee  Subgroup  in part (Blake 1984). It is correlated here more specifically with the Kurinelli Sandstone. Probably correlates with upper part of Junalki Formation which immediately underlies Unimbra Sandstone on southern margin of TENNANT CREEK.|16-MAY-23
21342|Brumbreu Formation|Defn author|Donnellan, N. 1995.|16-MAY-23
38038|Brumby Formation|Name source|A minor tributary of South Nicholson Creek, Brumby Creek, which drains north in the area around latitude 18o35'S, longitude 137o37'E in the MOUNT DRUMMOND.|16-MAY-23
38038|Brumby Formation|Unit history|A minor tributary of South Nicholson Creek, Brumby Creek, which drains north in the area around latitude 18o35'S, longitude 137o37'E in the MOUNT DRUMMOND.|16-MAY-23
38038|Brumby Formation|Geomorphic expression|Low hills and plains adjacent to the main ridges of the Carrara Range.|16-MAY-23
38038|Brumby Formation|Type section locality|Across strike ridges and valleys in central Carrara Range, from Latitude 18o37'33"S, Longitude 137o31'36"E to Latitude 18o37'11"S, Longitude 137o31'50"E [GR 766600 7938700 (base) to 767000 7939360 (top)].|16-MAY-23
38038|Brumby Formation|Extent|Confined to the Carrara Range and adjacent plains, in southeastern MOUNT DRUMMOND.|16-MAY-23
38038|Brumby Formation|Thickness range|350 m at the type section, thickening to the northwest and west to up to 800 m.|16-MAY-23
38038|Brumby Formation|Lithology|A heterogeneous unit including laminated and stromatolitic chert and possibly dolostone, chert-clast conglomerate and breccia, sandstone and granule conglomerate, and siltstone and shale.|16-MAY-23
38038|Brumby Formation|Depositional environment|Mainly shallow marine, ranging from supratidal to subtidal; some non-marine intervals - fluvial conglomerates and breccias, and in upper part of formation deeper marine, low energy environments.|16-MAY-23
38038|Brumby Formation|Relationships and boundaries|Conformable on the Drummond Formation, the contact being placed at the point where chert and fine siliciclastics become dominant over sandstone. The upper contact, with the Shady Bore Quartzite, is sharp but probably conformable; it is not exposed. Both upper and lower contacts correspond to marked topographic changes, which facilitates their mapping from air photographs. Parent unit: McNamara Group.|16-MAY-23
38038|Brumby Formation|Age reasons|Maximum age constrained by Top Rocky Rhyolite, dated at 1725+/-3 Ma (Page et al 2000); younger limit established by correlation with McNamara Group in Lawn Hill region to the east - eg, ages of 1658-1653 Ma for the Paradise Creek Formation (Page et al 2000), with which the Brumby Formation in part correlates with (see below).|16-MAY-23
38038|Brumby Formation|Correlations|On lithostratigraphic and sequence stratigraphic grounds, correlated with the Paradise Creek, Esperanza, and Lady Loretta Formations in the Lawn Hill region, 100 km to the east (Rawlings et al, in prep).|16-MAY-23
38038|Brumby Formation|Comments|Poor exposure makes detailed analysis of the internal stratigraphy of the formation very difficult. Note: All locations are based on the GDA94 geodetic datum. Standard series 1:250 000 sheet names are shown in upper case.|16-MAY-23
38038|Brumby Formation|References|**PAGE R.W., Jackson M.J. and Krassay A.A., 2000. Constraining sequence stratigraphy in north Australian basins: SHRIMP U-Pb zircon geochronology between Mt Isa and McArthur River. Australian Journal of Earth Sciences, 47, 3; 431-459.  **RAWLINGS D.J. Sweet I.P. and Kruse P.D., in prep.[2008] Mount Drummond, Northern Territory (Second Edition); 1:250 000 Geological Map Series, sheet SE53-12. Northern Territory Geological Survey, Map and Explanatory Notes.  **SMITH J.W. and Roberts H.G., 1963. Mount Drummond, N.T. (First Edition); 1:250,000 geological series, sheet SE53-12. Bureau of Mineral Resources, Geology and Geophysics, Map and Explanatory Notes.  **SWEET I.P., 1984. Carrara Range region, Northern Territory (First Edition); 1:100,000 geological series, portions of sheets 6460 and 6360. Bureau of Mineral Resources, Geology and Geophysics, Explanatory Notes.|16-MAY-23
37731|Buddycurrawa Volcanics|Name source|Buddycurrawa Creek, around latitude 18o10'S longitude 137o07'E, a tributary to the Nicholson River in MOUNT DRUMMOND.|16-MAY-23
37731|Buddycurrawa Volcanics|Unit history|Previously mapped within (ie not differentiated from) the 'Benmara beds' on the first edition of MOUNT DRUMMOND by Smith and Roberts (1963). Was also partly mismapped as Constance Sandstone by the same authors.|16-MAY-23
37731|Buddycurrawa Volcanics|Geomorphic expression|Recessive to mildly resistant with dark brown phototones.|16-MAY-23
37731|Buddycurrawa Volcanics|Type section locality|Along small low relief hill at latitude 18o8'S longitude 136o55'E in the headwaters of Whiterock Creek (newly approved by place names committee) in the Canyon Range in MOUNT DRUMMOND. Section runs from 703500E 7991950N (lower boundary stratotype) to approximately 702600E 7992200N (top).|16-MAY-23
37731|Buddycurrawa Volcanics|Extent|Northwestern corner of MOUNT DRUMMOND, in the Canyon Range (newly approved by place names committee).|16-MAY-23
37731|Buddycurrawa Volcanics|Thickness range|Ranges from 0 m to an estimated maximum of 300 m, implied from outcrop width and dip calculations. Basal ferruginous sandstone is 10-20 m thick.|16-MAY-23
37731|Buddycurrawa Volcanics|Lithology|Comprises an interval of ferruginous sandstone (basal unit), overlain by a mixed sequence of coherent trachyte, debris flow sandstone and conglomerate, mature sandstone, ferruginous siltstone/fine sandstone and minor but distinctive stromatolitic chert horizon(s).|16-MAY-23
37731|Buddycurrawa Volcanics|Relationships and boundaries|Rests conformably on Breakfast Sandstone, the boundary marked by a transition from relatively well-sorted quartzose sandstone into poorly-sorted ferruginous sandstone and ironstone. The volcanics are overlain by Bowgan Sandstone and, locally, Crow Formation of the South Nicholson Group. This contact is poorly exposed and relationships are speculative. Pinching out of the Benmara Group to the north near 705000E 8007000N is consistent with either an unconformity or a low-angle structural boundary (detachment) at the base of the South Nicholson Group. Rawlings et al (in prep) favour a slightly reactivated unconformity. Parent unit: Benmara Group.|16-MAY-23
37731|Buddycurrawa Volcanics|Age reasons|Constrained only by the underlying Murphy Metamorphics and Connellys Volcanics basement (>1845 Ma; Page et al 2000) and probable overlying South Nicholson Group (maximum age ~1500 Ma; by correlation with Roper Group; Jackson et al 1999, Abbott et al 2001). Unable to date the contained trachyte due to a lack of zircons and strong weathering (Rawlings et al in prep). The obvious interpretation is that the Buddycurrawa Volcanics are the same age as the Carrara Range Group and Peters Creek Volcanics (~1725 Ma), which also contain abundant felsic volcanics and shallow intrusives. However, an age closer to 1660-1580 Ma can be implied from their compositional similarity to magmatic rocks in the Coanjula area (Rawlings et al in prep).|16-MAY-23
37731|Buddycurrawa Volcanics|Correlations|Uncertain, but see discussion on age, above.|16-MAY-23
37731|Buddycurrawa Volcanics|Defn author|Rawlings, D.J. [approved 11-APR-2005]|16-MAY-23
37731|Buddycurrawa Volcanics|Comments|Note: All locations are based on the GDA94 geodetic datum. Standard series 1:250 000 sheet names are shown in upper case.|16-MAY-23
37731|Buddycurrawa Volcanics|References|ABBOTT S.T., Sweet I.P., Plumb K.A., Young D.N., Cutovinos A., Ferenczi P.A., Brakel A. and Pietsch B.A., 2001. Roper region: Urapunga and Roper River special, Northern Territory (Second Edition); 1:250 000 Geological Map Series, sheets SD53-10,11. Northern Territory Geological Survey-Australian Geological Survey Organisation (NGMA), Map and Explanatory Notes.  **JACKSON M.J., Sweet I.P., Page R.W. and Bradshaw B.E., 1999. The South Nicholson and Roper Groups: evidence for the early Proterozoic Roper Superbasin. In: Bradshaw B.E. and Scott D.L. (Eds.), Integrated basin analysis of the Isa Superbasin using seismic, well-log and geopotential data: an evaluation of the economic potential of the northern Lawn Hill Platform. Australian Geological Survey Organisation, Record 1999/19 (unpaginated).  **PAGE R.W., Jackson M.J. and Krassay A.A., 2000. Constraining sequence stratigraphy in north Australian basins: SHRIMP U-Pb zircon geochronology between Mt Isa and McArthur River. Australian Journal of Earth Sciences, 47, 3; 431-459.  **RAWLINGS D.J. Sweet I.P. and Kruse P.D., in prep.[2008] Mount Drummond, Northern Territory (Second Edition); 1:250 000 Geological Map Series, sheet SE53-12. Northern Territory Geological Survey, Map and Explanatory Notes.  **SMITH J.W. and Roberts H.G., 1963. Mount Drummond, N.T. (First Edition); 1:250,000 geological series, sheet SE53-12. Bureau of Mineral Resources, Geology and Geophysics, Map and Explanatory Notes.|16-MAY-23
2840|Bukalara Sandstone|Name source|Bukalara Plateau, eastern Bauhinia Downs 1:250 000 sheet area.|16-MAY-23
2840|Bukalara Sandstone|Unit history|Robinson Beds of Noakes (1956).|16-MAY-23
2840|Bukalara Sandstone|Geomorphic expression|Commonly plateau-forming; strongly jointed.|16-MAY-23
2840|Bukalara Sandstone|Type section locality|Boundary stratotypes: base at Mantungula 1:100 000 AMG229486 (latitude 15o50.5'S, longitude 135o12.9'E) unconformably overlying Middle Proterozoic Bessie Creek Sandstone; top at Mantungula 1:100 000 AMG 153514 (latitude 15o49.0'S, longitude 135o8.6'E) at base of conformably overlying Cox Formation, southwestern Mount Young 1:250 000 sheet area. Gently dipping, slightly folded type section lies between these two localities.|16-MAY-23
2840|Bukalara Sandstone|Extent|Hodgson Downs, Mount Young, Bauhinia Downs, Wallhallow, Robinson River, Tanumbirini, Calvert Hills and Mount Drummond 1:250 000 sheet areas.|16-MAY-23
2840|Bukalara Sandstone|Thickness range|Generally 30-100 m but 300 m in Bukalara Plateau (cf. Smith, 1964); estimated in range 200-450 m in type section.|16-MAY-23
2840|Bukalara Sandstone|Lithology|Red-brown thin- to thick-bedded, fine- to very coarse-grained quartz sandstone, often feldspathic; minor shale and conglomerate. Cross-bedding, ripples and slumping common.|16-MAY-23
2840|Bukalara Sandstone|Relationships and boundaries|Unconformable on various units of McArthur Basin, Murply Inlier and South Nicholson Basin. Conformably overlain by Cox Formation; presumed conformably overlain by Nutwood Downs Volcanics (Dunn, 1963); probably disconformably overlain by Top Springs Limestone (early Middle Cambrian).|16-MAY-23
2840|Bukalara Sandstone|Structure and Metamorphism|Horizontal to gently dipping, gently folded in places.|16-MAY-23
2840|Bukalara Sandstone|Age reasons|Trace fossil Skolithos indicates latest Precambrian or younger. Deemed to be Early Cambrian on basis of presumed conformity with putative Early Cambrian Nutwood Downs Volcanics. Unconformably beneath early Middle Cambrian Top Springs Limestone.|16-MAY-23
2840|Bukalara Sandstone|Correlations|Buckingham Bay Sandstone (Arafura Basin).|16-MAY-23
21356|Bukudal Granite|Name source|Bukudal Outstation (AMG PF750658,  Arnhem Bay - Gove)|16-MAY-23
21356|Bukudal Granite|Unit history|Outcrop now mapped as this unit was previously mapped as the central and southern areas of the 'Caledon Granite' and as the 'Myaoola Complex' by Dunnet (1965) and Plumb and Roberts (1992). These two names have now been abandoned.|16-MAY-23
21356|Bukudal Granite|Geomorphic expression|The main outcrop comprises islands, hills, pavements, tors and boulders.|16-MAY-23
21356|Bukudal Granite|Type section locality|Entire outcrop area, centred on lat. 13degrees 58'30"S, long.136degrees 35'30"E, west of Bukadal Outstation.|16-MAY-23
21356|Bukudal Granite|Extent|30 by 17 km in southeastern part of Arnhem Bay - Gove, centred around Caledon and Trial Bays and 35 by 25 km in the northeastern part of Blue Mud Bay - Port Langdon, around Myaoola Bay.|16-MAY-23
21356|Bukudal Granite|Relationships and boundaries|Intrudes the Bradshaw Complex at PF865942 and is probably coeval with the Garrthalala Granite around that locality. It is unconformably overlain by Coast Range Sandstone along the Coast Range (Haines and others, 1997) and elsewhere by Cretaceous and Cainozoic sediments and Quaternary alluvium. Swarms of microgranite/aplite dykes locally intrude the Bukudal Granite.|16-MAY-23
21356|Bukudal Granite|Age reasons|The Bukudal Granite has an Orosirian age based on three SHRIMP U-Pb zircon age determinations (Page, pers. comm., 1996). These are 1835, 1836 and 1837 (all +/-4) Ma, determined from samples collected from AMG PF716612, PF558462 and PF565522.|16-MAY-23
21356|Bukudal Granite|Correlations|Probably comagmatic with the Giddy, Dhalinybuy and Garrthalala Granites, which may in fact connect at depth. Regionally, may correlate with granites of the Pine Creek Inlier (Cullen Batholith) and Murphy Inlier (Nicholson Granite).|16-MAY-23
21356|Bukudal Granite|Defn author|T. L. Madigan and D.J. Rawlings, 1997.|16-MAY-23
29219|Bullion Schist|Name source|Named after the Home of Bullion mine (AMG GR MS126207) on the Home of Bullion 1:100 000 sheet (5754).|16-MAY-23
29219|Bullion Schist|Unit history|Originally mapped as undifferentiated Arunta Block (Smith and Milligan, 1964).|16-MAY-23
29219|Bullion Schist|Geomorphic expression|Low, undulating terrain with small strike ridges. Common vein quartz ridges.|16-MAY-23
29219|Bullion Schist|Type section locality|Near the Home of Bullion mine between AMG GR MS122203 (latitude 21o30'53"S, longitude 134o09'08"E) and GR MS124214 (latitude 21o30'19"S, longitude 134o09'16") on the Home of Bullion sheet (5754). Here most of the rock types described below are present except for the porphyritic felsic volcanics.|16-MAY-23
29219|Bullion Schist|Extent|Southeastern part of the Crawford 1:100 000 sheet area (5655), southern part of the Taylor 1:100 000 sheet area (5755), western part of the Home of Bullion 1:100 0000 sheet area (5754), and the northeastern part of the Barrow 1:100 000 sheets (5654).|16-MAY-23
29219|Bullion Schist|Thickness range|Unknown due to incomplete sections and structural complexities. About 2 km of section is exposed in the type area (no base or top exposed) provided that it contains no unrecognised isoclinal folding.|16-MAY-23
29219|Bullion Schist|Lithology|(In decreasing order of abundance): Metapelite: fine-grained quartz-muscovite schist and quartz-muscovite-biotite schist, fine-grained quartz-sericite/muscovite+andalusite schist; fine chlorite common, common opaque minerals, elongate aggregates of sericite and chloritoid (up to 30 mm diameter) at AMG GR LS762328 and near Home of Bullion mine may be retrograde alteration of cordierite or staurolite(?); thinly bedded.  Meta-arenite to wacke: fine- to coarse-grained quartz + plagioclase/microcline-muscovite and/or biotite schist, common opaque minerals; rare sillimanite; some fine chlorite; very fine- to fine-grained quartz-tourmaline and quartz-muscovite-tourmaline rock near Barrow Creek Granite Complex; thinly bedded (e.g. at AMG GR LS905317 and GR MS112239).  Quartz-mica schist: fine- to coarse-grained, quartz-biotite (sometimes retrogressed to chlorite)-sericite/muscovite+andalusite+microcline/plagioclase+cordierite+anthophyllite+garnet+opaques (e.g. at the Home of Bullion mine).  Metamorphosed porphyritic felsic volcanics (e.g. at AMG GR MS043244).  Amphibolite: generally coarse tremolite/actinolite, altered plagioclase and fine opaque accessories, common secondary quartz and chlorite (e.g. at AMG GR LS767279).|16-MAY-23
29219|Bullion Schist|Relationships and boundaries|The base is never exposed. Unconformably overlain by the Hatches Creek Group as suggested by geophysics, although the contact is not exposed. Unconformably overlain by late Proterozoic strata. Intruded by the Barrow Creek Granitic Complex. Considered to be part of the Arunta Block.|16-MAY-23
29219|Bullion Schist|Structure and Metamorphism|Tightly to isoclinally folded, faulted.|16-MAY-23
29219|Bullion Schist|Age reasons|Early Proterozoic or older as it is overlain by the Hatches Creek Group, which is considered to have a maximum age of early Proterozoic (Blake and others, 1987).|16-MAY-23
29219|Bullion Schist|Correlations|May correlate with the Lander Rock beds (Stewart and others, 1980) on the basis of lithological similarity.|16-MAY-23
38039|Bullrush Conglomerate|Name source|From Bullrush Spring, a small spring in Little Cleanskin Creek, at latitude 18o41'S, longitude 137o53'E, in MOUNT DRUMMOND.|16-MAY-23
38039|Bullrush Conglomerate|Unit history|Previously mapped as Maloney Formation (South Nicholson Group) on the first edition of MOUNT DRUMMOND by Smith and Roberts (1963), and as lower Musselbrook Formation (McNamara Group) by Sweet (1985). Both Maloney and Musselbrook are now obsolete units, although the Bullrush Conglomerate is still included in the McNamara Group.|16-MAY-23
38039|Bullrush Conglomerate|Geomorphic expression|A series of ridges in the type section, narrowing to a single small ridge to the west.|16-MAY-23
38039|Bullrush Conglomerate|Type section locality|From south to north, base at GR 778030 7960060 (latitude 18o25'53"S longitude 137o37'55"E) in Maloney Creek, past the confluence with the South Nicholson River to GR 777630 7959010 (latitude 18o26'27"S longitude 137o37'42"E). The section is accessible via a rough track from Wangalinji Outstation, a small settlement 20 km west of the type section.|16-MAY-23
38039|Bullrush Conglomerate|Extent|Restricted to an area known (geologically) as the Maloney Creek Inlier (Sweet 1985), in eastern MOUNT DRUMMOND, in the headwaters of the South Nicholson River and one of its tributaries, Maloney Creek.|16-MAY-23
38039|Bullrush Conglomerate|Thickness range|From a maximum of 500 m, in the type section, to 50 m near Bullrush Spring, 10 km west of the type section.|16-MAY-23
38039|Bullrush Conglomerate|Lithology|Polymictic granule, pebble and cobble conglomerate in units up to 20 m thick, alternating with cross-bedded sandstone, minor silicified carbonates and reddish brown to fawn, fine-grained lithic sandstone and siltstone. The carbonate beds are altered to chert, with relict stratiform, domal, conical and digitate stromatolites, and parallel lamination.|16-MAY-23
38039|Bullrush Conglomerate|Depositional environment|Alluvial fan and fan delta, depositing into background sedimentation representing shallow marine and peritidal carbonate flat environments.|16-MAY-23
38039|Bullrush Conglomerate|Relationships and boundaries|Overlies the Drummond Formation and Top Rocky Rhyolite unconformably; contact is sharp and marked by an abrupt change to conglomerate. Overlain by the Plain Creek Formation, probably conformably. Parent unit: McNamara Group.|16-MAY-23
38039|Bullrush Conglomerate|Age reasons|Maximum age constrained by Top Rocky Rhyolite, dated at 1725+/-3 Ma (Page et al 2000); younger limit established by correlation with McNamara Group in Lawn Hill region to the east - eg, ages of 1647+/-8 and 1644+/-8 Ma for the Riversleigh Siltstone (Page et al 2000), which overlies the Shady Bore Quartzite, the probable Bullrush Conglomerate correlative (see Correlations).|16-MAY-23
38039|Bullrush Conglomerate|Correlations|Probable equivalent of the Shady Bore Quartzite in the Carrara Range to the south, and in the Lawn Hill region 100 km to the east (Rawlings et al, in prep).|16-MAY-23
38039|Bullrush Conglomerate|Defn author|Sweet, I. P. [approved 11-APR-2005]|16-MAY-23
38039|Bullrush Conglomerate|Comments|This facies is not present in McNamara Group in any other locality, and it is the stratigraphic position of the Bullrush Conglomerate, in roughly the middle of the McNamara Group and at the transition from dominantly carbonate environments below, to deeper marine siliciclastic-dominated environments above, which allows its correlation as described above. Note: All locations are based on the GDA94 geodetic datum. Standard series 1:250 000 sheet names are shown in upper case.|16-MAY-23
38039|Bullrush Conglomerate|References|  **PAGE R.W., Jackson M.J. and Krassay A.A., 2000. Constraining sequence stratigraphy in north Australian basins: SHRIMP U-Pb zircon geochronology between Mt Isa and McArthur River. Australian Journal of Earth Sciences, 47, 3; 431-459.  **RAWLINGS D.J. Sweet I.P. and Kruse P.D., in prep [2008]. Mount Drummond, Northern Territory (Second Edition); 1:250 000 Geological Map Series, sheet SE53-12. Northern Territory Geological Survey, Map and Explanatory Notes.  **SMITH J.W. and Roberts H.G., 1963. Mount Drummond, N.T. (First Edition); 1:250,000 geological series, sheet SE53-12. Bureau of Mineral Resources, Geology and Geophysics, Map and Explanatory Notes.  **SWEET I.P., 1985. Relationship of the Maloney Creek Inlier to other elements of the western Lawn Hill Platform Cover, northern Australia. BMR Journal of Geology and Geophysics, 9; 329-338.|16-MAY-23
23442|Bunghara Metamorphics|Name source|Bunghara Outstation 133o 22' 23o 16.5'.|16-MAY-23
23442|Bunghara Metamorphics|Unit history|Previously variously Mount Zeil granulite (informal, Glikson 1984) Adla Granulite (Offe 1983), unassigned metamorphic rocks (Offe & Shaw 1983).|16-MAY-23
23442|Bunghara Metamorphics|Geomorphic expression|Low rough hills.|16-MAY-23
23442|Bunghara Metamorphics|Type section locality|Approximately 2 to 2.5km southeast of No.15 Bore GR 236100 7415200 Glen Helen 1:100 000 Sheet area.|16-MAY-23
23442|Bunghara Metamorphics|Extent|Low Hills north of the MacDonnell Ranges, from Mount Solitaire (Alice Springs Sheet area) to Mount Heughlin, probably extend into the Mount Liebig Sheet area.|16-MAY-23
23442|Bunghara Metamorphics|Lithology|Granofels and migmatite ranging from mafic to felsic in composition, mafic granulite, quartzofeldspathic gneiss, metasediments.|16-MAY-23
23442|Bunghara Metamorphics|Relationships and boundaries|Intruded by Mount Zeil Granite, Forty Five Augen Gneiss.|16-MAY-23
23442|Bunghara Metamorphics|Structure and Metamorphism|Complexly deformed, metamorphosed to granulite facies grade, commonly overprinted by fabric of Redbank Thrust Zone.|16-MAY-23
23442|Bunghara Metamorphics|Age reasons|Middle Proterozoic: intruded by granite at 1760 Ma (Black & Shaw 1992)|16-MAY-23
23442|Bunghara Metamorphics|Correlations|Part of Narwietooma Metamorphic Complex, equated with Sliding Rock Metamorphics, possibly deformed to form Illyabba Metamorphics.|16-MAY-23
23442|Bunghara Metamorphics|Defn author|R.D. Shaw, R.G. Warren. Teyssier, G.A. Wakelin-King, 1 July 1991.|16-MAY-23
23442|Bunghara Metamorphics|Comments|This 'definition' is missing the details of references mentioned in the synonymy and age, and shows no signs on the card of having been approved.|16-MAY-23
3012|Bungitina metamorphics|Name source|Named after Bungitina Well (cba) on the upper reaches of Maude Creek, 9 km south of Mount Brassey in the northeastern part of the Riddoch 1:100 000 Sheet area.|16-MAY-23
3012|Bungitina metamorphics|Unit history|A group of lensic bodies of quartz feldspathic gneiss, referred to by Joklik (1955 p.43) as the Bungitina Granodiorite (R4787, R4588) are identical to many other quartzofeldspathic gneisses in the principal outcrop area, so Joklik's  unit has been extended to include all the quartzo feldspathic gneisses and subordinate mafic rocks that together had been mapped by Joklik as granitised Irindina Gneiss.|16-MAY-23
3012|Bungitina metamorphics|Type section locality|Reference Section: Florence Creek between GR 5851-847427 and 836381.|16-MAY-23
3012|Bungitina metamorphics|Extent|The principal outcrop area is a rugged belt of hills and ridges, some 3 km wide, which strike south-southwest from Mount Brassey in the Alice Springs 1:250 000 Sheet area. The metamorphics also crop out near the confluence of Florence and Maude Creeks, and between Muller Flat Dam and the junction of Florence Creek with the Hale River.|16-MAY-23
3012|Bungitina metamorphics|Lithology|The metamorphics consist mainly of a very fine grained quartzofeldspathic gneiss which is generally garnetiferous and subordinate amphibolite. Rarer rock types include clinopyroxene or hornblende bearing plagioclase rock, garnet quartzite, biotite schist, calc-silicate rock and megacrystic feldspar gneiss. An unusual Mg-rich unit noted for its basemetal content is present at the Oonagalabi Prospect. The Mg-unit includes anthophyllite rock and clinopyroxene rock. Informal subdivision of unit: The unit is informally subdivided into a presumed lower (pCsb2) and upper (pCsb1) units. The lower unit is more extensive, has a higher proportion of quartzofeldspathic gneiss, contains amphibolite bodies that are commonly discordant and lensic. The upper unit contains a more diverse group of rock types including the Mg-rich rock, the megacrystic feldspar gneiss, and a schistose garnetiferous biotite gneiss. Rock types common to both informal units include the distinctive quartzofeldspathic gneiss, amphibolite, hornblende- or clinopyroxene plagioclase rock and calc-silicate rock.|16-MAY-23
3012|Bungitina metamorphics|Relationships and boundaries|The metamorphics are assigned to the Strangways Metamorphic Complex. They are thought to be conformably overlain by the Cadney metamorphics and unconformably overlain by the Irindina gneiss which belongs to the Harts Range Group. The relationship between the Bungitina metamorphics and the Naringa calcareous member of the Irindina Gneiss which directly overlies it is obscured by a zone of tectonic disturbance which develops into a major tectonic slide. Locally, porphyroblastic K-feldspar gneiss assigned to the Baume Gneiss, also belonging to the Harts Range Group, overlies the Bungitina metamorphics (e.g. along Florence Creek upstream of its junction with Maude Creek). At the southwestern extremity of the principal outcrop area highly deformed Bungitina metamorphics pass progressively into the Gough Dam Schist Zone; the boundary being arbitrarily defined by the incoming of muscovite and, as such, is largely a reflection of metamorphic grade.|16-MAY-23
3012|Bungitina metamorphics|Age reasons|The age of the metamorphics in unknown. They are presumed to have been regionally metamorphosed at 1800 m.y. like other units of the Strangways Metamorphic Complex, but are thought to have undergone a later second metamorphism to account for the extremely fine recrystallised texture.|16-MAY-23
33171|Burash Sandstone|Name source|Burash Waterhole, in eastern part of Tanumbirini 1:250 000 sheet area (16o11'S, 134o50'E).|16-MAY-23
33171|Burash Sandstone|Unit history|Equivalent to the upper part of `Masterton Formation' mapped on Tanumbirini sheet (Paine, 1963).|16-MAY-23
33171|Burash Sandstone|Geomorphic expression|White resistant ridges.|16-MAY-23
33171|Burash Sandstone|Type section locality|Adjacent to Five Mile Spring around 16o07.5', 134o54.5'E. The 370 m thick type section runs from 489670E 8217180N (16o07.5'S, 134o54.2'E; base) to 487950E 8216250N (16o08.05'S, 134o53.2'E; top), the former also representing the lower boundary stratotype. No upper boundary stratotype is assigned.|16-MAY-23
33171|Burash Sandstone|Extent|Exposed only in the northeastern part of the Tanumbirini sheet area, along Eight Mile Creek, in the Tanumbirini Inlier.|16-MAY-23
33171|Burash Sandstone|Thickness range|>370 m.|16-MAY-23
33171|Burash Sandstone|Lithology|White to pink, silicified, cross-bedded, fine- to medium-grained quartzose sandstone, with minor coarse or granular intervals near top.|16-MAY-23
33171|Burash Sandstone|Depositional environment|High-energy shallow water environment.|16-MAY-23
33171|Burash Sandstone|Relationships and boundaries|Conformably overlies the Nyanantu Formation, the contact marked by a transition from pebbly lithic (volcanogenic) sandstone into medium-grained quartzose sandstone. Overlain by Roper Group, but contact not exposed.|16-MAY-23
33171|Burash Sandstone|Age reasons|Palaeoproterozoic. Maximum age constrained by SHRIMP U-Pb zircon date of ~1713 Ma for underlying Tanumbirini Rhyolite (Page and Sweet, 1998). Conformable relationship suggests Burash Sandstone is only marginally younger than this date.|16-MAY-23
33171|Burash Sandstone|Correlations|Possibly the Parson Range Group in eastern Arnhem Land.|16-MAY-23
33171|Burash Sandstone|Comments|The outcrops now assigned to the Burash Sandstone were initially assigned by Paine (1963) to the `Masterton Formation', a mixed volcanic and sedimentary package. Jackson et al. (1987) subsequently applied the name Masterton Sandstone to the sandstone units and assigned separate names to the volcanic components. The Masterton Sandstone is now known to be the basal unit of the McArthur Group. As the sandstones overlying the Tanumbirini Rhyolite in this area have greater affinity with the Tawallah Group, and can not be readily correlated with the Masterton Sandstone or any of the upper units of the Tawallah Group, a new name is required.|16-MAY-23
33171|Burash Sandstone|References|JACKSON M. J., MUIR M. D. & PLUMB K. A. 1987. Geology of the southern McArthur Basin, Northern Territory. Bureau of Mineral Resources, Australia, Bulletin 220, 173pp. **PAGE R. W. & SWEET I. P. 1998. Geochronology of basin phases in the western Mount Isa Inlier, and correlation with the McArthur Basin. Australian Journal of Earth Sciences 45, 219-232. **PAINE A. G. L. 1963. Tanumbirini, N.T.; 1:250,000 geological series, sheet SE53-2. Bureau of Mineral Resources, Geology and Geophysics, Map and Explanatory Notes.|16-MAY-23
27284|Burt Bluff Gneiss|Name source|Burt Bluff in Alice Springs 1:100 000 Sheet area GR5650-674714.|16-MAY-23
27284|Burt Bluff Gneiss|Type section locality|Along Jay Creek north of the Native Settlement.|16-MAY-23
27284|Burt Bluff Gneiss|Extent|Crops out between Chewings Range and Heavitree Quartzite Ridge extending westwards from near Burt Bluff to about 5 km west of Jay Creek Native Settlement (Iwupataka) in MacDonnell Ranges 1:100 000 Sheet area.|16-MAY-23
27284|Burt Bluff Gneiss|Lithology|Schistose augen gneiss and subordinate laminated even-grained granitic gneiss. Commonly the feldspar augen are up to 3 cm long and enclosed in a fine to medium-grained matrix of biotite-quartz-feldspar.|16-MAY-23
27284|Burt Bluff Gneiss|Relationships and boundaries|Interfingers with the Rungutjirba Gneiss (new name); this contact may be intrusive. Unconformably ;overlain by the Heavitree Quartzite and intruded by dolerite dykes of the Stuart Dyke Swarm (new name).|16-MAY-23
27284|Burt Bluff Gneiss|Identifying features|Reason for proposed name:  Distinctive unit quite different in rock type from neighbours.|16-MAY-23
27284|Burt Bluff Gneiss|Age reasons|Oldedr than Late Proterozoic Heavitree Quartzite which unconformably overlies it and the dolerite dykes which intrude it. Thought to be of equivalent metamorphic age as other units of the Iwupataka Metamorphic Complex (new name) i.e. about 1620 m.y.|16-MAY-23
27284|Burt Bluff Gneiss|Proposed publication|Geological report on the 1:100 000 scale mapping of southeastern Arunta Block, Alice Springs 1:250 000 Sheet area, Northern Territory by R D Shaw et al. BMR.  Microfiche report in prep.|16-MAY-23
21402|Bustard Subgroup|Name source|Bustard Island (GR PE500850) in BLUE MUD BAY.|16-MAY-23
21402|Bustard Subgroup|Unit history|Formerly mapped as part of the now abandoned 'Groote Eylandt beds' (Plumb and Roberts, 1965,1992).|16-MAY-23
21402|Bustard Subgroup|Constituents|In ascending order Erringkarri Rhyolite, Abarungkwa Sandstone, Bickerton Rhyolite, Milyakburra Formation, located on or adjacent to Bickerton Island. The Milyema Formation on northern Groote Eylandt and adjacent islands is probably a lateral equivalent of Milyakburra Formation.|16-MAY-23
21402|Bustard Subgroup|Type section locality|As for each component formation.|16-MAY-23
21402|Bustard Subgroup|Extent|Bickerton Island, Bustard Island and northern most islands north of Groote Eylandt.|16-MAY-23
21402|Bustard Subgroup|Thickness range|The composite maximum thicknesses is about 500m.|16-MAY-23
21402|Bustard Subgroup|Lithology|Sandstone, conglomerate and felsic volcanic rocks.|16-MAY-23
21402|Bustard Subgroup|Relationships and boundaries|Unconformably overlies the Grindall Formation. The Milyema Formation is disconformably overlain by the Alyinga Sandstone of the Alyangula Subgroup.|16-MAY-23
21402|Bustard Subgroup|Age reasons|Orosirian (Palaeoproterozoic). The Bickerton Rhyolite has been dated using SHRIMP single-zircon U-Pb techniques at ~1815 Ma (Pietsch, et al. 1994).|16-MAY-23
21402|Bustard Subgroup|Correlations|Possible correlative of Edith River Group.|16-MAY-23
83054|Cackleberry Metacarbonates|Name source|According to Shaw (1985), named after Cackleberry Bore (Bore Number RN001232 https://nrmaps.nt.gov.au/knowyourbore_desktop.html) in HUCKITTA 1:250 000 mapsheet (135.3564degreesE 22.5961degreesS).|16-MAY-23
83054|Cackleberry Metacarbonates|Unit history|The revised Cackleberry Metacarbonate member is a subset of the former Cackleberry Metamorphics (abandoned name: Reno et al 2018, 2020), which were first defined by Shaw et al (1985) as a unit consisting of metacarbonate, metamudstone and quartzofeldspathic rocks that outcrop in and west of the Mopunga Range in southwestern HUCKITTA (Freeman 1986, Weisheit et al in prep). Metamudstone and quartzofeldspathic rocks of former Cackleberry Metamorphics are now grouped with other units of Deep Bore Metamorphics.|16-MAY-23
83054|Cackleberry Metacarbonates|Geomorphic expression|Commonly blocky and boulder outcrops with typical dark-grey to brown weathering rind that highlights competent layers. Locally fresh and massive. Occurs in hills, ridges, and subcrop.|16-MAY-23
83054|Cackleberry Metacarbonates|Type section locality|No single outcrop contains all variations of the Cackleberry Metacarbonate. A type locality occurs on a ridge at 135.4551degreesE 22.6939degreesS (GDA2020). Reference localities include good exposures  in the eastern Mopunga Range at 135.5873degreesE 22.712degreesS and 135.5834degreesE 22.7112degreesS (GDA2020), and south of the Mopunga Range north of Halfway Dam (around 135.4527degreesE 22.692egreesS (GDA2020)) in southwestern and south-central HUCKITTA. Access to the outcrops are via public roads and private tracks. Some off-track driving/walking might be required.|16-MAY-23
83054|Cackleberry Metacarbonates|Description at type locality|The type locality is a ridge of microcrystalline to medium-grained calc-silicate rock and marble that is compositionally layered in the mm- to cm-scale, or massive with cm-scale egg-shaped calcite aggregates.|16-MAY-23
83054|Cackleberry Metacarbonates|Extent|The unit outcrops in the Deep Bore Domain north of the Delny Shear Zone, south of the Georgina Basin, between Little Frazer Creek and the Elua Range in south-central and western HUCKITTA (~135.2723-135.8282degreesE and ~22.5704-22.8034degreesS (GDA2020)).|16-MAY-23
83054|Cackleberry Metacarbonates|General description|Calc-silicate rocks and marble interlayered at the m- to 100 m-scale with other units of the Deep Bore Metamorphics. Commonly discontinuous layers and lenses, stretched, boudinaged and folded during regional deformation.|16-MAY-23
83054|Cackleberry Metacarbonates|Thickness range|1-100 m layers and lenses represent apparent thicknesses due to post-depositional shearing and folding.|16-MAY-23
83054|Cackleberry Metacarbonates|Lithology|Type locality includes microcrystalline to medium-grained calc-silicate rock and marble that is compositionally layered in the mm- to cm-scale, or massive with cm-scale egg-shaped calcite aggregates. The calcite aggregates are commonly rimmed by mm-scale hematite or magnetite, giving them an egg-like (cackleberry) appearance. Other phases include epidote, quartz, plagioclase, and garnet. Reference localities include microcrystalline to medium-grained calc-silicate rocks and marble that are massive or compositionally layered in the mm- to cm-scale, with local dm- to m-scale layering. Commonly epidote-altered quartz-calcite-dolomite-plagioclase-diopside-hornblende rocks and massive quartz-calcite rocks. Rare fine-grained, layered para-amphibolite.|16-MAY-23
83054|Cackleberry Metacarbonates|Depositional environment|Possibly indicating (shallow) marine conditions in a back-arc basin for the precursor sedimentary rock (see Deep Bore Metamorphics).|16-MAY-23
83054|Cackleberry Metacarbonates|Relationships and boundaries|Commonly interlayered with other constituent units of the Deep Bore Metamorphics. Intruded by and included as xenoliths in rocks of the Black Label Suite, Marshall Granite and possibly Dinkum Orthogneiss.|16-MAY-23
83054|Cackleberry Metacarbonates|Identifying features|The oldest and only metacarbonate unit north of the Delny Shear Zone and west of the Elua Fault Zone in HUCKITTA.|16-MAY-23
83054|Cackleberry Metacarbonates|Structure and Metamorphism|Commonly weakly to moderately foliated parallel to compositional layering; locally massive; locally gneissic, schistose, mylonitic. Stretching, boudinage, isoclinal folding are common. Amphibolite to granulite facies; retrogressed proximal to shear zones.|16-MAY-23
83054|Cackleberry Metacarbonates|Age reasons|Interlayered with other units of the Deep Bore Metamorphics that were dated to have been deposited between ca 1.82-1.79 Ga (see definition card of Deep Bore Metamorphics).|16-MAY-23
83054|Cackleberry Metacarbonates|Correlations|Interpreted to be age-equivalent to Bonya, Kanandra, and Perenti metamorphics of the Aileron Province.|16-MAY-23
83054|Cackleberry Metacarbonates|Alteration and Mineralisation|Commonly epidote-altered, locally biotite-muscovite altered. K-feldspar-quartz-epidote-garnet alteration common proximal to Marshall Granite. Around Molyhil W-Mo deposit, Cackleberry Metacarbonate are skarn altered and host to exogene epigenetic mineralisation (eg McGloin and Weisheit 2022).|16-MAY-23
83054|Cackleberry Metacarbonates|Geophysical Expression|No clear magnetic, gravity or radiometric character due to the lack of continuous outcrop and dominance of meta-igneous rocks in the area. However, locally associated with magnetic-high and rarely with magnetic-low trends.|16-MAY-23
83054|Cackleberry Metacarbonates|Defn author|Anett Weisheit, Barry Reno, Eloise Beyer, Pablo Farias (Department of Primary Industry and Resources, Northern Territory Geological Survey) 3-MAY-2022.|16-MAY-23
83054|Cackleberry Metacarbonates|References|Freeman MJ, Black LA, Offe LA, Senior BR, Shaw RD, Shergold JH, Simpson CJ, Walter MR, Warren RG, Donnellan N, Horsfall CJ, Laurie JR and Walley AM, 1986. Huckitta, Northern Territory (Second Edition). 1:250 000 geological map series, SF 53-11. Northern Territory Geological Survey, Darwin.  **McGloin MV and Weisheit A, 2021. Epigenetic copper and tungsten mineralisation in JINKA and JERVOIS RANGE, northeastern Aileron Province. Northern Territory Geological Survey, Record.  **Reno BL, Beyer EE, Thompson JM and Meffre S, 2018. NTGS laser ablation ICP-MS zircon petrochronology project: Aileron Province, Jinka and Dneiper 1:100 000 mapsheets. Northern Territory Geological Survey, Record 2018-003.   **Reno BL, Beyer EE, Weisheit A and PG Farias 2022. Jinka, Northern Territory. 1:100 000 geological map series explanatory notes, 6052. Northern Territory Geological Survey, Darwin.  **Reno BL, Weisheit A, Beyer EE, Thompson JM and Meffre S, 2020. Summary of results. NTGS laser ablation ICP?MS in situ monazite geochronology project: Aileron and Irindina Provinces, Jinka and Dneiper 1:100 000 map sheets. Northern Territory Geological Survey, Record 2020-008.  **Shaw, R.D., Warren, R.G., Freeman, M.J., 1985, Stratigraphic definitions of named units in the Arunta Block, Northern Territory, 1979-82., Bureau of Mineral Resources, Australia, Report, 260.  **Weisheit A et al, in prep. Huckitta, Northern Territory. 1:250 000 geological map series explanatory notes, SF53-11. Northern Territory Geological Survey, Darwin.|16-MAY-23
24806|Cahill Formation|Name source|Mount Cahill on the Cahill 1:100 000 Sheet area 5472, Northern Territory. Grid Ref. 507,765.|16-MAY-23
24806|Cahill Formation|Unit history|Dunn, 1962 included these rocks in his 'South Alligator Group' and suggested some exposures were Koolpin Formation.|16-MAY-23
24806|Cahill Formation|Type section locality|No surface exposure gives an adequate indication of the lithology of the unit due to deep weathering and cover of younger strata. The succession within the unit has been adequately established by rotary-percussion drill traverses in the Cahill and Jim Jim sheet areas (BMR Jim Jim Nos 1-70 inclusive, BMR Cahill Nos 15-77 inclusive, drill holes) and all exposures of the unit can be suitably correlated with the drill traverse data. Of the 3 traverses drilled, the Jabiru Traverse is the proposed type section, and the Koongarra and Mount Basedow Traverses are suitable reference sections. Full results of the drilling are given by Stuart-Smith & Hone, 1976. The drill traverses are shown graphically on continuation card no. 3. The best surface exposure is a road cutting on the Arnhem Highway at 398019 in the Cahill Sheet area - see continuation card no. 4. The dip of the beds in the type section varies from 0o to 90o with a predominance of dips between 35o and 45o.|16-MAY-23
24806|Cahill Formation|Extent|Throughout the Alligator Rivers Uranium field, east of the South Alligator River; from the south end of Mt Partridge Range in the southwest, to the Cooper Creek area in the north: southeast extent not known under younger station.|16-MAY-23
24806|Cahill Formation|Thickness range|Range 2000-3000 m.|16-MAY-23
24806|Cahill Formation|Lithology|A lower carbonate-carbonaceous schist sequence (pyritic carbonaceous mica schist, chloritized feldspathic quartzite, quartzschist, amphibole schist, dolomite, chert) and an upper feldspathic quartzite and quartz schist sequence (interlayered feldspathic quartzschist, feldspathic schist, feldspathic quartzite, minor amphibolite, mica schist and quartzo-feldspathic gneiss). In the centre of the uranium field exposure is mostly quartzite, and silicified carbonate. The metamorphic grade is generally staurolite-almandine sub-facies of the amphibolite facies; dominance of phyllite over schist in the Jim Jim Sheet area suggest a slightly low metamorphic grade in that area;; in the Oenpelli Sheet area in the northeast, the Cahill Formation is folded into the migmatite terrain of the Nimbuway Complex and gneiss and migmatite predominate - however, marble, quartzite and carbonaceous schist still identify the unit.|16-MAY-23
24806|Cahill Formation|Relationships and boundaries|Overlies (contact is sheared, probably unconformable) Lower Proterozoic Mount Partridge Formation and Archaean-Lower Proterozoic Nanambu Complex (metapsammite, phyllite; leucocratic gneiss and granite) (Needham et al., 1974). Carbonate rock types mostly indicate proximity of base. Transitionally (contact appears gradational) overlain by Lower Proterozoic Fisher Creek Siltstone (Walpole et al., 1968).|16-MAY-23
24806|Cahill Formation|Age reasons|Lower Proterozoic. Metamorphosed by ~1800 m.y. regional event, overlies Nanambu Complex mantled gneiss dome reactivated at ~2020 m.y. (Page, 1974).|16-MAY-23
24806|Cahill Formation|Correlations|The Cahill Formation represents broadly similar facies to the penecontemporaneous Koolpin and Golden Dyke Formations which were deposited in the western and southern parts of the Pine Creek Geosyncline.|16-MAY-23
24806|Cahill Formation|Proposed publication|To be presented at 25th IGC; to be published thereafter, title journal TBA|16-MAY-23
68909|Camooweal Dolostone|Name source|From town of Camooweal in western Queensland.|16-MAY-23
68909|Camooweal Dolostone|Unit history|Camooweal Dolomite of Öpik (1954, 1956a).|16-MAY-23
68909|Camooweal Dolostone|Geomorphic expression|Prominent hills to low rubbly outcrops; well exposed in dissected terrain; disoriented boulders on clay-rich soil plains.|16-MAY-23
68909|Camooweal Dolostone|Type section locality|Type section and lower boundary stratotype at 8.4-174.0 m depth in cored drillhole NTGS01/1 (eastern RANKEN; Kruse 2003). Lower boundary at conformable contact with Wonarah Formation, at sharp change from mid-grey dolomudstone below into thin mid-grey phosclast conglomerate above. Section terminates at base of overlying grey-black clay-rich soil. Reference area: Upper boundary reference area in vicinity of Lake Nash Anticline, where well exposed Camooweal Dolostone in Lake Nash Anticline (southeastern AVON DOWNS) is near moderate outcrop of similar rocks attributed to Arrinthrunga Formation about 10 km to the south in northeastern SANDOVER RIVER. Intervening contact area is concealed beneath Austral Downs Limestone and grey-black clay-rich soil.|16-MAY-23
68909|Camooweal Dolostone|Extent|Undilla Sub-basin in central Georgina Basin: URANDANGI, MOUNT ISA, CAMOOWEAL, LAWN HILL, AVON DOWNS, RANKEN, MOUNT DRUMMOND.|16-MAY-23
68909|Camooweal Dolostone|Thickness range|Drillhole thicknesses: 165.6+ m in type section, 186+ m in BMR Cattle Creek 1, 100-122+ m in Lake Nash 1.|16-MAY-23
68909|Camooweal Dolostone|Lithology|Dolostone; minor marl and quartz sandstone; basal intraclast, ooid and oncoid dolostone and quartz sandstone.|16-MAY-23
68909|Camooweal Dolostone|Depositional environment|Basal high-energy peritidal to shallow subtidal barrier, passing upward into restricted to epeiric back-barrier.|16-MAY-23
68909|Camooweal Dolostone|Relationships and boundaries|Conformable between Ranken Formation and Wonarah Formation below and apparently, Arrinthrunga Formation above. Laterally interdigitates with Age Creek Formation in CAMOOWEAL (Shergold et al 1985, Southgate and Shergold 1991). Parent unit: Barkly Group.|16-MAY-23
68909|Camooweal Dolostone|Age reasons|Middle Cambrian: latest Floran or early Boomerangian to notionally early Mindyallan. Lower age limit based on underlying fossiliferous Ranken Limestone and Wonarah Formation; upper age limit based on apparent conformity with overlying unfossiliferous, notionally Upper Cambrian Arrinthrunga Formation.|16-MAY-23
68909|Camooweal Dolostone|Correlations|Possibly Anthony Lagoon beds of Barkly Sub-basin; Age Creek Formation, V Creek Limestone, Mail Change Limestone, Devoncourt Limestone and/or Roaring Siltstone of Undilla Sub-basin; upper Arthur Creek Formation of southern Georgina Basin.|16-MAY-23
68909|Camooweal Dolostone|Comments|The nominated type section and upper boundary reference area together supersede the type area of Öpik (1954), along the Georgina River between Lake Mary and Lake Francis, respectively north and south of Camooweal, which includes neither an upper nor a lower boundary.|16-MAY-23
80604|Canefire Granite|Name source|Canefire Dam (135.3299degreesE 22.7232degreesS (GDA 2020)) in HUCKITTA 1:250 000 mapsheet, Northern Territory.|16-MAY-23
80604|Canefire Granite|Geomorphic expression|isolated hills, nubbins, and pavements.|16-MAY-23
80604|Canefire Granite|Type section locality|135.6193degreesE 22.7584degreesS (GDA2020); access via private tracks.|16-MAY-23
80604|Canefire Granite|Description at type locality|Fresh boulders and tors at the type locality are typical of the Canefire Granite in lower strain zones within the Delny Shear Zone. At this location, the granite consists of quartz-K-feldspar-plagioclase-biotite that is strongly porphyritic with abundant tabular to elongate K-feldspar megacrysts with aspect ratios of 1:2 to 1:5 and long axes ranging in length from 3-10 cm. The megacrysts are strongly aligned and define a penetrative structural fabric. Simple twins in K-feldspar are common, and concentric growth zoning is noted in some euhedral crystals. Biotite comprises around 10 vol% of the mineral mode. Aggregates of biotite form zones that anastomose around K-feldspar megacrysts and define a well-developed grain shape foliation that parallels aligned K-feldspars.|16-MAY-23
80604|Canefire Granite|Extent|Outcrops in the Kanandra Domain of southwestern HUCKITTA (Weisheit et al in prep) and possibly eastern ALCOOTA (Beyer et al in prep) 1:250 000 mapsheets, west of the abandoned Molyhil mine, north of Plenty and Marshall rivers and south of the Mopunga Range (west of 135.72degreesE and between 22.6323- 22.7678degreesS (GDA 2020)).|16-MAY-23
80604|Canefire Granite|General description|Canefire Granite is a fine- to coarse-grained, porphyritic biotite-granite to leucogranite. The unit is fresh to moderately weathered. It is locally migmatitic and commonly foliated to gneissic, and locally mylonitic. Rare pegmatitic gneiss and aplite are also included in the unit. It was formed by partial melting of the Kanandra Metamorphics. It is one of two granites of the Alkara Suite and distinguished from the Jamaica Granite by the lack of garnet.|16-MAY-23
80604|Canefire Granite|Lithology|Consists of quartz-K-feldspar-plagioclase-biotite that is strongly porphyritic with abundant tabular to elongate K-feldspar megacrysts with aspect ratios of 1:2 to 1:5 and long axes ranging in length from 3?10 cm. The megacrysts are strongly aligned and define a penetrative structural fabric. Simple twins in K-feldspar are common, and concentric growth zoning is noted in some euhedral crystals. Biotite comprises around 10 vol% of the mineral mode. Aggregates of biotite form zones that anastomose around K-feldspar megacrysts and define a well-developed grain shape foliation that parallels aligned K-feldspars.|16-MAY-23
80604|Canefire Granite|Depositional environment|Genesis: Canefire Granite, although lacking garnet, is classified as an S-type derived from a less fertile rock type. Interpreted to have formed via melting of thickened metasedimentary crust.|16-MAY-23
80604|Canefire Granite|Relationships and boundaries|Anatectic granite derived from partial melting of Kanandra Metamorphics, which occur as xenoliths in the granite. Intruded into Carmencita Metadolerite. Intruded by Jamaica Granite with diffuse contacts.|16-MAY-23
80604|Canefire Granite|Identifying features|Garnet-free, variably-deformed porphyritic biotite-granite.|16-MAY-23
80604|Canefire Granite|Structure and Metamorphism|Anatectic granite formed during a Palaeoproterozoic tectonothermal cycle. Commonly gneissic to locally undeformed; mylonitic in shear zones. Locally retrogressed to greenschist facies in shear zones.|16-MAY-23
80604|Canefire Granite|Age reasons|SHRIMP 207Pb/206Pb zircon age of 1735 +/- 4 Ma (Kositcin and Reno 2020).|16-MAY-23
80604|Canefire Granite|Correlations|Interpreted as co-magmatic and co-genetic with Jamaica Granite, a constituent unit of the Alkara Suite, based on similar geochemical and isotopic composition, and timing of structural fabric development.|16-MAY-23
80604|Canefire Granite|Alteration and Mineralisation|Isolated outcrops are commonly moderately to strongly weathered. Locally bleached, silicified, sericitised. No known associated mineralisation.|16-MAY-23
80604|Canefire Granite|Geophysical Expression|Correspond partly with magnetic high trends.|16-MAY-23
80604|Canefire Granite|Geochemistry|S-type monzogranite. ASI value of 1.05 indicating a composition that is moderately peraluminous. LREE-enrichment, negatively-sloping HREEs, and moderately negative Eu anomaly.|16-MAY-23
80604|Canefire Granite|Defn author|Barry Reno, Anett Weisheit, Eloise Beyer, Pablo Farias (NT Department of Industry, Tourism and Trade, Northern Territory Geological Survey) 3-MAY-2022.|16-MAY-23
80604|Canefire Granite|References|Beyer E et al, 2022. Alcoota, Northern Territory (Second Edition). 1:250 000 geological map series explanatory notes, SF53-11. Northern Territory Geological Survey, Darwin, Record 2022-007.  **Beyer EE and Whelan JA, 2021. Revising the igneous stratigraphy in the eastern Aileron Province: implications for geodynamic setting between ca 1.81-1.71 Ga. Annual Geoscience Exploration Seminar (AGES) Proceedings, Alice Springs, Northern Territory, 20-21 April 2021. Northern Territory Geological Survey, Darwin.  **Kositcin N and Reno BL, 2020. Summary of results. Joint NTGS?GA geochronology project: Aileron and Irindina provinces, Jinka and Dneiper 1:100 000 mapsheets, 2019. Northern Territory Geological Survey, Record 2020-001.  **Reno BL, Weisheit A, Beyer EE and PG Farias 2022. Jinka, Northern Territory. 1:100 000 geological map series explanatory notes, 6052. Northern Territory Geological Survey, Darwin.  **Weisheit A et al, in prep. Huckitta, Northern Territory (Third Edition). 1:250 000 geological map series explanatory notes, SF53-11. Northern Territory Geological Survey, Darwin.|16-MAY-23
24210|Canulgerra Sandstone|Name source|Canulgerra Rockhole on Yaddanilla Creek, at GR 650968, Hanlon 1:100 000 Sheet area, Frew River 1:250 000 Sheet are.|16-MAY-23
24210|Canulgerra Sandstone|Type section locality|4 km NW of Canulgerra Rockhole (latitude 20o49'30"S, longitude 135o37'30"E), Hanlon 1:100 000 Sheet area: from GR 615006, where the formation conformably overlies Lennee Creek Formation, to GR 632020, where it is overlain conformably by Vaddingilla Formation. Here the Canulgerra Sandstone is about 500 m thick, dips 15o-30oE, and is well exposed in strike ridges.|16-MAY-23
24210|Canulgerra Sandstone|Extent|Three outcrop areas, one in western Hanlon 1:100 000 Sheet area, the other two in eastern central Bonney and eastern central Davenport Range 1:100 000 Sheet areas, Bonney Well 1:250 000 Sheet area.|16-MAY-23
24210|Canulgerra Sandstone|Thickness range|Generally about 500 m.|16-MAY-23
24210|Canulgerra Sandstone|Lithology|Ridge-forming quartzose to feldspathic arenite and interbanded recessive friable arenite, micaceous siltstone, and mudstone; minor conglomerate.|16-MAY-23
24210|Canulgerra Sandstone|Relationships and boundaries|Conformable on recessive Lennee Creek Formation and overlain conformably by recessive Vaddingilla Formation; basal contact invariably concealed. Lower and upper contacts taken at abrupt topographic change from ridge-forming arenite of the Canulgerra Sandstone to recessive beds of underlying and overlying units.|16-MAY-23
24210|Canulgerra Sandstone|Age reasons|Younger than 1870 m.y. - U-Pb zircon age of volcanics in the Warramunga Group, which is overlain unconformably by the Hatches Creek Group. Older than 1640 m.y.-Rb-Sr wholerock approximate age of granite intruding the Hatches Creek Group.|16-MAY-23
24210|Canulgerra Sandstone|Comments|Relatively resistant (ridge forming) formation in between two recessive formations. Part of the Hanlon Subgroup of the Hatches Creek Group.|16-MAY-23
80337|Cappocks Granodiorite|Name source|Cappocks Waterhole (619581mE 7496951mN, GDA94, Zone 53) in Jervois Range 1:100 000 mapsheet, Northern Territory.|16-MAY-23
80337|Cappocks Granodiorite|Unit history|Previously unnamed biotite-hornblende granodiorite, and part of Mascotte Gneiss in second edition Huckitta 1:250 000 mapsheet (Freeman et al 1986).|16-MAY-23
80337|Cappocks Granodiorite|Geomorphic expression|Nubbins, isolated boulders, small pavements.|16-MAY-23
80337|Cappocks Granodiorite|Type section locality|South of the Johannsen Range at 612691mE 7495398mN (GDA94, Zone 53), access via private tracks.|16-MAY-23
80337|Cappocks Granodiorite|Extent|Between Twins Bore (605039mE 7495920mN) and Valley Bore (623280mE 7488944mN, GDA94, Zone 53) in Jervois Range 1:100 000 mapsheet.|16-MAY-23
80337|Cappocks Granodiorite|General description|Fine- to medium-grained, inequigranular granodiorite, subordinate diorite, and monzogranite; locally biotite-rich with approximately 15-30 vol% brown to red-brown to green-brown biotite, green to blue (sodic?) hornblende locally developed in association with biotite; rare occurrence of allanite and trace apatite; foliation defined by aligned biotite and hornblende (where present) and elongate quartz.|16-MAY-23
80337|Cappocks Granodiorite|Lithology|Massive grey granodiorite, generally fresh, <1 mm red-brown weathering rind, fine- to medium-grained, inequigranular quartz-plagioclase-K-feldspar-biotite, approximately 7 vol% brown biotite.|16-MAY-23
80337|Cappocks Granodiorite|Depositional environment|Continental margin environment, either arc cordillera or back arc basin, or derived from melting of pre-existing crust that formed in a continental margin environment.|16-MAY-23
80337|Cappocks Granodiorite|Relationships and boundaries|Interpreted to intrude Bonya Metamorphics possibly parallel to compositional layering with minor cross-cutting (contacts not exposed); inferred to intrude White Violet Orthogneiss and Mascotte Orthogneiss; intruded by Samarkand Pegmatite.|16-MAY-23
80337|Cappocks Granodiorite|Identifying features|Inequigranular granodiorite.|16-MAY-23
80337|Cappocks Granodiorite|Structure and Metamorphism|Moderately- to well-developed grain shape foliation in melanocratic parts, locally developed gneissic foliation characterised by mm-thick discontinuous biotite±hornblende-rich and quartz-plagioclase-rich bands; intruded prior to regional high-thermal-gradient amphibolite-facies metamorphism.|16-MAY-23
80337|Cappocks Granodiorite|Age reasons|Upper intercept age of 1773 ± 3 Ma interpreted as magmatic crystallisation (SHRIMP U-Pb, Kositcin et al. 2011); deformed by regional deformation dated at ca 1.76 Ga (LA-ICP-MS U-Pb monazite, Reno et al. 2016)|16-MAY-23
80337|Cappocks Granodiorite|Correlations|Interpreted to be comagmatic and cogenetic with constituent units of the Casper Suite, based on similar geochemical and isotopic composition, and timing of structural fabric development.|16-MAY-23
80337|Cappocks Granodiorite|Alteration and Mineralisation|Secondary magnetite and muscovite, chlorite alteration, sericitisation, local epidotisation. No known economic mineralisation.|16-MAY-23
80337|Cappocks Granodiorite|Geophysical Expression|Outcrops occur in an area of magnetic low signal and gravity low signal; radiometric high signal.|16-MAY-23
80337|Cappocks Granodiorite|Geochemistry|I-type; granodiorite, diorite, minor monzogranite; weakly metaluminous to strongly peraluminous compositions; low-K (tholeiitic), calc-alkaline and high-K (calc-alkaline) compositions. Steep to moderately sloping LREE, gently sloping to flat HREE, negative Eu anomalies.|16-MAY-23
80337|Cappocks Granodiorite|Defn author|Anett Weisheit, Barry Reno, Eloise Beyer (Northern Territory Geological Survey)  27-JUN-2018.|16-MAY-23
80337|Cappocks Granodiorite|Proposed publication|Weisheit A, Reno BL and Beyer EE, in review. Jervois Range Special, Northern Territory. 1:100 000 geological map explanatory notes, 6152 and part 6252. Northern Territory Geological Survey, Darwin.|16-MAY-23
80337|Cappocks Granodiorite|References|Freeman MJ, Black LA, Offe LA, Senior BR, Shaw RD, Shergold JH, Simpson CJ, Walter MR, Warren RG, Donnellan N, Horsfall CJ, Laurie JR and Walley AM, 1986. Huckitta, Northern Territory (Second Edition). 1:250 000 geological map series, SF 53-11. Northern Territory Geological Survey, Darwin.  **Kositcin N, Magee CW, Whelan JA and Champion DC, 2011. New SHRIMP geochronology from the Arunta Region: 2009-2010. Geoscience Australia, Record 2011/14.  **Reno BL, Whelan JA, Weisheit A, Kraus S, Beyer EE, Meffre S and Thompson J, 2016. Summary of Results. NTGS laser ablation ICP-MS in situ monazite and xenotime geochronology project: Arunta Region, Jervois Range 1:100 000 mapsheet. Northern Territory Geological Survey, Record 2016-004.|16-MAY-23
76181|Caramal Amphibolite|Name source|After Caramal uranium prospect (MODAT - NTGS Mineral Occurrences Database) GDA 94 53L 321417mE 8617558mN (-12°30'1"S 133°21'24"E) on Alligator River 1:250 000 mapsheet, boundary between Oenpelli and Howship 1:100 000 mapsheets, Nimbuwah Domain, Pine Creek Orogen, Northern Territory.|16-MAY-23
76181|Caramal Amphibolite|Unit history|Zamu Complex (in part; Stewart 1959 unpublished, as cited in Ferguson and Needham 1978, modified Bryan 1962 and Walpole 1962); Zamu Dolerite (in part; Ferguson and Needham 1978).|16-MAY-23
76181|Caramal Amphibolite|Geomorphic expression|Platform river-washed outcrop exposed in drainage systems, and as prominent boulder outcrops in Cahill 1:100 000 mapsheet.|16-MAY-23
76181|Caramal Amphibolite|Type section locality|River washed platform exposure of amphibolite in Caramal Inlier on Alligator River 1:250 000 mapsheet, Howship 1:100 000 mapsheet. GDA 94 53L 326382mE 8615913mN (-12°30'56"S  133°24'8"E).|16-MAY-23
76181|Caramal Amphibolite|Description at type locality|River-washed platform exposure. Amphibolite has equilibrium textures of granoblastic hornblende and plagioclase, and contains hornblende-bearing leucosomes that cross-cut and are deformed into north-south-trending foliation.|16-MAY-23
76181|Caramal Amphibolite|Extent|Constrained to the Nimbuwah Domain|16-MAY-23
76181|Caramal Amphibolite|General description|Exposed in creek beds in Caramal and Myra Falls Inliers in Oenpelli and Howship 1:100 000 mapsheets and also as prominent boulder outcrops in Cahill 1:100 000 mapsheet.|16-MAY-23
76181|Caramal Amphibolite|Thickness range|Not known.|16-MAY-23
76181|Caramal Amphibolite|Lithology|Fine- to coarse-grained amphibolite; olive-green to brown  hornblende and locally sericitised polysynthetic twinned plagioclase defines foliation.|16-MAY-23
76181|Caramal Amphibolite|Depositional environment|/Genesis: Probably originally an intrusive rock.|16-MAY-23
76181|Caramal Amphibolite|Relationships and boundaries|Contact relationships not observed, but occurs within Neoarchaean Kukalak Gneiss and Palaeoproterozoic Cahill Formation and Nourlangie Schist.|16-MAY-23
76181|Caramal Amphibolite|Identifying features|Displays weak foliation and has restricted occurrences within Neoarchaean Kukalak Gneiss and Palaeoproterozoic Cahill Formation. It comprises granoblastic hornblende and plagioclase and hornblende-bearing leucosomes that are cross-cut by foliation. It has chemical affinities similar to EMORB and shows extreme enrichment in both incompatible and compatible elements relative to Primitive Mantle (PM) and strong enrichment in the most incompatible elements relative to Normal Mid-Ocean Ridge Basalt (NMORB). It typically displays strong potassic enrichment. Compared to the Zamu Dolerite (Fergusson and Needham, 1978) the Caramal Amphibolite has much lower abundances of the Light Rare Earth Elements (LREE) La and Ce and the High Field Strength Elements (HFSE) Th and Hf.|16-MAY-23
76181|Caramal Amphibolite|Structure and Metamorphism|Amphibolite-facies metamorphism.|16-MAY-23
76181|Caramal Amphibolite|Age reasons|Not adequately constrained, but most likely Palaeoproterozic as occurs within Palaeoproterozoic Cahill Formation and Nourlangie Schist.|16-MAY-23
76181|Caramal Amphibolite|Correlations|None known.|16-MAY-23
76181|Caramal Amphibolite|Alteration and Mineralisation|Sericitisation of plagioclase feldspar.|16-MAY-23
76181|Caramal Amphibolite|Geophysical Expression|In Cahill 1:100 000 mapsheet, prominent outcrops are coincident with strong linear magnetic trend attributed to Cahill Formation.|16-MAY-23
76181|Caramal Amphibolite|Geochemistry|Mostly low-Ti tholeiitic composition, relatively flat Rare Earth Element (REE) pattern.|16-MAY-23
76181|Caramal Amphibolite|Defn author|Hollis JA and Glass LM, 2012|16-MAY-23
76181|Caramal Amphibolite|Proposed publication|Hollis JA and Glass LM, 2012. Howship and Oenpelli, Northern Territory. 1:100 000 geological map series explanatory notes, 5572, 5573. Northern Territory Geological Survey, Darwin.|16-MAY-23
76181|Caramal Amphibolite|References|Bryan R, 1962. Lower Proterozoic basic intrusive rocks of the Katherine-Darwin area, Northern Territory. Bureau of Mineral Resources, Australia, Record 1962/07.***Walpole BP, 1962. Mount Evelyn, Northern Territory, 1:250 000 Geological Series Explanatory Notes, SD53/5. Bureau of Mineral Resources, Australia, Canberra.***Ferguson J and Needham RS, 1978. The Zamu Dolerite: A lower Proterozoic preorogenic continental tholeiitic suite from the Northern Territory, Australia. Journal of the Geological Society of Australia 25(6), 309-322.|16-MAY-23
83559|Carmencita Metadolerite|Name source|Carmencita Bore in southwestern HUCKITTA 1:250 000 mapsheet, Northern Territory (135.1841degreesE 22.8453degreesS (GDA 2020)).|16-MAY-23
83559|Carmencita Metadolerite|Unit history|Previously included as the main constituent of the `Kanandra Granulite? of Shaw et al (1975) and Freeman (1986), which included felsic gneiss, mafic granulite, migmatitic paragneiss, and calc-silicate rocks. Reserved, and initally published as Carmencita Granulite.|16-MAY-23
83559|Carmencita Metadolerite|Geomorphic expression|Generally fresh or mildly weathered with a thin patina or weathering rind; rare intensely weathered reddish versions. Commonly forming piles of boulders, tors, hills, and ridges.|16-MAY-23
83559|Carmencita Metadolerite|Type section locality|Around Black Point in southwestern HUCKITTA (Weisheit et al in prep; 135.1361degreesE 22.7553degreesS (GDA2020)). Access to the outcrops are via public roads and private tracks. Some off-track driving/walking might be required.|16-MAY-23
83559|Carmencita Metadolerite|Extent|Central and western HUCKITTA and eastern ALCOOTA: north of the Plenty River, west of the Elua Range, south and southwest of the Mopunga Range and around Mount Swan.|16-MAY-23
83559|Carmencita Metadolerite|General description|Granulite-facies, migmatitic metamafic rocks: fine- to medium-grained clinopyroxene-orthopyroxene-plagioclase mafic granulites with variable amounts of primary and secondary hornblende and opaque oxides. The unit is commonly migmatitic with mm- to m-scale leucocratic segregations of fine- to coarse-grained plagioclase-quartz+/-pyroxene veins. Intruded into Kanandra Metamorphics as m?km-wide layers, commonly layer-parallel to the Kanandra Metamorphics (sills). Deformed into m- to 500 m-wide lenses and boudins within regional shear zones where they are also retrogressed to amphibolite facies. The unit is intruded by rocks of the Alkara Suite.|16-MAY-23
83559|Carmencita Metadolerite|Thickness range|Decimetre-scale to up to 300 m thick. Ranging from dm-thick up to 500 m wide layers, lenses and boudins.|16-MAY-23
83559|Carmencita Metadolerite|Lithology|Medium- to fine-grained, equigranular, granoblastic orthopyroxene-clinopyroxene-plagioclase mafic granulite. Fresh to weakly weathered; kaolinised plagioclase. Weak to strong alignment of minerals parallel to locally developed cm-thick plagioclase+/-quartz-rich and pyroxene-rich layers. Occurs as dm- to up to 300 m-thick layers and zones within Kanandra Metamorphics. Layering and foliation are parallel to compositional layering and gneissic foliation in Kanandra Metamorphics.|16-MAY-23
83559|Carmencita Metadolerite|Depositional environment|Genesis: Possible nascent continental rift setting where mafic melts interacted with crustal wall rock.|16-MAY-23
83559|Carmencita Metadolerite|Relationships and boundaries|Regionally interpreted to form sills that intruded into the Kanandra Metamorphics; possibly minor dykes; sills are up to 1-2 km long and 500 m wide; intruded by rocks of the Alkara Suite.|16-MAY-23
83559|Carmencita Metadolerite|Identifying features|It is the only mafic granulite in the Kanandra Domain in southwestern HUCKITTA and eastern ALCOOTA 1:250 000 mapsheet (Shaw et al 1975, Beyer et al 2022).|16-MAY-23
83559|Carmencita Metadolerite|Structure and Metamorphism|Commonly granoblastic with weak to moderate grain-shape foliation and local mylonitic foliation. Upper amphibolite to granulite facies; locally migmatitic. Commonly grading from granulite facies into amphibolite facies proximal to major shear zones.|16-MAY-23
83559|Carmencita Metadolerite|Age reasons|No absolute age constraints; intruded as early as 1.78 Ga based on a spread of concordant zircon 207Pb/206Pb LA-ICP-MS dates (Beyer et al 2013).|16-MAY-23
83559|Carmencita Metadolerite|Correlations|Intruded into Kanandra Metamorphics as interpreted sills; intruded by rocks of the Alkara Suite. Possibly age-equivalent to rocks of the Baikal Supersuite.|16-MAY-23
83559|Carmencita Metadolerite|Alteration and Mineralisation|Minor sericitisation; locally retrogressed and metasomatically altered in shear zones (garnet- and hornblende-bearing). No known association with mineralisation; speculated to be a source of Cu for locally occurring epigenetic Cu occurrences (McGloin and Weisheit 2021).|16-MAY-23
83559|Carmencita Metadolerite|Geophysical Expression|Anomalous magnetic low and high response; no characteristic gravity or radiometric response.|16-MAY-23
83559|Carmencita Metadolerite|Geochemistry|Whole rock geochemistry plots in Basalt/gabbro, basaltic andesite/gabbroic diorite fields; calc-alkaline, low-K (tholeiitic); weak to moderate LREE-enrichment, flat to weakly sloping HREE, weak to moderate negative Eu anomalies; transition between N-MORB and E-MORB.|16-MAY-23
83559|Carmencita Metadolerite|Defn author|Anett Weisheit, Barry Reno, Eloise Beyer, Pablo Farias (NT Department of Industry, Tourism and Trade, Northern Territory Geological Survey) 3-MAY-2022.|16-MAY-23
83559|Carmencita Metadolerite|References|Beyer E et al, 2022. Alcoota, Northern Territory (Second Edition). 1:250 000 geological map series explanatory notes, SF53-11. Northern Territory Geological Survey, Darwin, Record 2022-007.  **Beyer EE, Hollis JA, Whelan JA, Glass LM, Donnellan N, Yaxley G, Armstrong R, Allen C and S Schersten A, 2013. Summary of results. NTGS laser ablation ICPMS and SHRIMP U-Pb, Hf and O geochronology project: Pine Creek Orogen, Arunta Region, Georgina Basin and McArthur Basin, July 2008?May 2011. Northern Territory Geological Survey, Record 2012-007.  **Freeman MJ, Black LA, Offe LA, Senior BR, Shaw RD, Shergold JH, Simpson CJ, Walter MR, Warren RG, Donnellan N, Horsfall CJ, Laurie JR and Walley AM, 1986. Huckitta, Northern Territory (Second Edition). 1:250 000 geological map series, SF 53-11. Northern Territory Geological Survey, Darwin.  **McGloin MV and Weisheit A, 2021. Epigenetic copper and tungsten mineralisation in JINKA and JERVOIS RANGE, northeastern Aileron Province. Northern Territory Geological Survey, Record.   **Shaw RD, Warren RG, Kopras J and Green DE, 1975. Alcoota, Northern Territory (Second Edition). 1:250 000 geological map series explanatory notes, SF53-10. Northern Territory Geological Survey, Darwin.  **Weisheit A et al, in prep. Huckitta, Northern Territory. 1:250 000 geological map series explanatory notes, SF53-11. Northern Territory Geological Survey, Darwin.|16-MAY-23
80344|Casper Suite|Name source|After the Casper Fe-Ti-V prospect (640492 mE 7495058 mN, GDA94, Zone53) in Jervois Range 1:100 000 mapsheet, Northern Territory.|16-MAY-23
80344|Casper Suite|Constituents|White Violet Orthogneiss, Attutra Metagabbro, Kings Legend Metadolerite, Xanten Granodiorite, Cappocks Granodiorite, Jervois Granodiorite. Also contains a poorly exposed unnamed granodiorite.|16-MAY-23
80344|Casper Suite|Geomorphic expression|Generally poorly exposed; scattered outcrops; low, blocky or rounded outcrops; jointed pavements; bouldery hills, ridges, tors; sills and minor dykes.|16-MAY-23
80344|Casper Suite|Extent|Constituent units sporadically outcrop in the western and central area in the Jervois Range 1:100 000 mapsheet, north of the Marshall River and south and southeast of the Johannsen and Jervois ranges (between ca 7473000mN-7503000mN and 595000mE-657000mE, GDA94, Zone 53).|16-MAY-23
80344|Casper Suite|General description|Constituent units vary in composition: metagabbro, metadolerite, granodiorite with subordinate tonalite, diorite, quartz diorite, monzodiorite and quartz monzodiorite. All constituent units are deformed by a regional main foliation. Local concordant intrusive relationships with Bonya Metamorphics, locally contains xenoliths of Bonya Metamorphics; locally exposed intrusive relationships between the constituent units; intruded by Tarlton Granite, Boundary Igneous Complex and Samarkand Pegmatite; locally unconformably overlain by Oorabra Arkose and Grant Bluff Formation of the Georgina Basin; locally faulted contacts with various units of the Georgina Basin.|16-MAY-23
80344|Casper Suite|Depositional environment|Continental margin environment, either arc cordillera or back arc basin, or derived from melting of pre-existing crust that formed in a continental margin environment.|16-MAY-23
80344|Casper Suite|Structure and Metamorphism|All constituent units are overprinted by the regional main foliation ranging from weakly to strongly foliated (grain shape foliation) and gneissic, mafic rocks locally undeformed; locally overprinted by mylonitic foliation along and adjacent to fault zones; all constituent units deformed during regional high-thermal gradient amphibolite facies metamorphism but metamorphic overprint is not always apparent.|16-MAY-23
80344|Casper Suite|Age reasons|Crystallisation ages of constituent units vary between ca 1.79-1.77 Ga (LA-ICP-MS zircon U-Pb, Beyer et al 2018; SHRIMP 207Pb/206Pb, Claoue-Long and Hoatson 2005, Cross et al 2005, Kositcin et al 2011, 2014, 2018, Zhao and Bennett 1995); all constituent units are deformed by the regional deformation event that occurred at ca 1.76 Ga (LA-ICP-MS U-Pb monazite, Reno et al 2016).|16-MAY-23
80344|Casper Suite|Correlations|Interpreted as co-magmatic and co-genetic with Fosters Suite and Mascotte Orthogneiss of the Baikal Supersuite based on similar geochemical and isotopic composition, and timing of structural fabric development.|16-MAY-23
80344|Casper Suite|Alteration and Mineralisation|Local K-feldspar¿quartz alteration, hematitisation, silicification and brecciation, quartz and calcite veining is common close to shear zones; sporadic copper mineralisation in the Kings Legend Metadolerite and iron-titanium-vanadium mineralisation in the Attutra Metagabbro.|16-MAY-23
80344|Casper Suite|Geophysical Expression|When extensive enough the constituent felsic units are characterised by magnetic-low signals, often with a magnetic-high contact aureole; the constituent mafic units have a magnetic anomalously low signal; no clear gravity signal; felsic units are characterised by a radiometric high signal, mafic units show a radiometric low signal.|16-MAY-23
80344|Casper Suite|Geochemistry|I-type intrusives; dominantly peraluminous and less commonly metaluminous compositions, calc-alkaline to low-K compositions, enriched in LREE compared to HREE, negative Eu anomalies variably developed, juvenile to evolved Nd isotopic signatures.|16-MAY-23
80344|Casper Suite|Defn author|Anett Weisheit, Barry Reno, Eloise Beyer (Northern Territory Geological Survey) 01-MAY-2018|16-MAY-23
80344|Casper Suite|Proposed publication|Weisheit A, Reno BL and Beyer EE, in review. Jervois Range Special, Northern Territory. 1:100 000 geological map explanatory notes, 6152 and part 6252. Northern Territory Geological Survey, Darwin.|16-MAY-23
80344|Casper Suite|References|Beyer EE, Reno BL, Weisheit A, Whelan JA, Thompson JM, Meffre S and Woodhead JD, 2018. Summary of results. NTGS laser ablation ICP-MS U-Pb-Hf geochronology project: selected samples from JERVOIS RANGE 1:100 000 and TOBERMOREY 1:250 000 mapsheets, Aileron and Irindina provinces, January 2014 - December 2016. Northern Territory Geological Survey, Record 2018-001.  **Claoué-Long JC and Hoatson DM, 2005. Proterozoic mafic-ultramafic intrusions in the Arunta Region, central Australia. Part 2: event chronology and regional correlations. Precambrian Research 142, 134-158.  **Cross A, Claoué-Long JC, Scrimgeour IR, Ahmad M and Kruse PD 2005. Summary of results. Joint NTGS-GA geochronology project: Rum Jungle, basement to the Georgina Basin and eastern Arunta Region 2001-2003. Northern Territory Geological Survey Record 2005-006.  **Kositcin N, Magee CW, Whelan JA and Champion DC, 2011. New SHRIMP geochronology from the Arunta Region: 2009-2010. Geoscience Australia, Record 2011/14.  **Kositcin N, Beyer EE and Whelan JA, 2014. Summary of results. Joint NTGS¿GA SHRIMP geochronology project: Arunta Region, July 2013-June 2014. Northern Territory Geological Survey, Record 2014-008.  **Kositcin N, Reno BL and Beyer EE, 2018. Summary of results. Joint NTGS¿GA geochronology project: Aileron Province, July 2015-June 2016. Northern Territory Geological Survey, Record 2018-005.  **Reno BL, Whelan JA, Weisheit A, Kraus S, Beyer EE, Meffre S and Thompson J, 2016. Summary of Results. NTGS laser ablation ICP-MS in situ monazite geochronology project: Arunta Region, July 2013-June 2014. Northern Territory Geological Survey, Record.  **Zhao JX and Bennett VC, 1995. SHRIMP U¿Pb zircon geochronology of granites in the Arunta Inlier, central Australia: implications for Proterozoic crustal evolution. Precambrian Research 71, 17-43.|16-MAY-23
21470|Cato Volcanics|Name source|Cato River (AMG PG500390, Arnhem Bay 1:250 000 scale mapsheet area), a tidal- and fresh-water river which flows into the eastern side of Arnhem Bay.|16-MAY-23
21470|Cato Volcanics|Unit history|Previously undifferentiated "Spencer Creek Volcanics" of Dunnet (1965).|16-MAY-23
21470|Cato Volcanics|Geomorphic expression|Typically recessive outcrop of blocks, boulders and low rubbly rises.|16-MAY-23
21470|Cato Volcanics|Type section locality|At lat. 12o11'20''S, long. 136o30'E. Base of section is at AMG PG636512 (Arnhem Bay) and top is at PG618528 (Gove mapsheet area). However, as actual contacts are not exposed, no boundary stratotypes could be defined.|16-MAY-23
21470|Cato Volcanics|Extent|Outcrop is confined to a very small area 20 km northwest of Yanungbi outstation, adjacent to the Peter John River floodplain, in northeastern Arnhem Bay and northwestern Gove 1:250 000 scale mapsheet areas.|16-MAY-23
21470|Cato Volcanics|Thickness range|400 m at type section. To the north and south, the sequence has been removed by the unconformity at the base of the overlying Mount Bonner Sandstone.|16-MAY-23
21470|Cato Volcanics|Lithology|Pink, red or brown felsic igneous rock (rhyolite). It is porphyritic, with phenocrysts of K-feldspar, quartz, and minor plagioclase and pyroxene, set in a dark brown to black cryptocrystalline groundmass. Some of the fresher outcrop is very hard and has a notable sugary texture and sub-conchoidal fracture, suggesting it has been recrystallised. Possible relict pyroclastic textures in thin-section.|16-MAY-23
21470|Cato Volcanics|Depositional environment|Most likely extrusive (volcanic), possibly pyroclastic.|16-MAY-23
21470|Cato Volcanics|Relationships and boundaries|Upper igneous unit of the Spencer Creek Group. Apparently conformably or mildly disconformably overlying the Yuduyudu Formation and probably disconformably overlain by the Rorruwuy Sandstone. The contact with the underlying unit is poorly exposed and is interpreted as conformable on the basis of concordance, and the absence of unconformity-diagnostic features. The contact with the overlying Rorruwuy Sandstone is also poorly exposed, but is interpreted as disconformable... There is apparent concordance between the two units, and the basal sandstone beds are mature and free of conglomerate. Sandstone is also locally overturned (faulted?) adjacent to the contact, suggesting it may be partly faulted. Along strike, beyond the present exposures, the Cato Volcanics are probably unconformably overlain by Mount Bonner Sandstone.|16-MAY-23
21470|Cato Volcanics|Age reasons|Palaeoproterozoic (Statherian). The age of this formation, from analysis of single zircon grains by SHRIMP U-Pb geochronological techniques, is ~1710 Ma (Rawlings and others, in prep.).|16-MAY-23
21470|Cato Volcanics|Correlations|Rawlings and others (in prep.) and Rawlings (1994) suggest correlation with the upper parts of the Tawallah and Katherine River Groups in the southern and western McArthur Basin respectively. Locally, it correlates to the felsic igneous Fagan Volcanics in southern Arnhem Bay and northern Blue Mud Bay, and tentatively with the Gadabara Volcanics in eastern Blue Mud Bay mapsheet areas. These correlations are based on geochemical, petrological, lithostratigraphic and geochronological constraints, and the physical form of igneous units.|16-MAY-23
21470|Cato Volcanics|References|DUNNET, D., 1965- Arnhem Bay/Gove, Northern Territory - 1:250 000 Geological Series. Bureau of Mineral Resources, Australia, Explanatory Notes, SD53-3, 4. **RAWLINGS, D. J., 1994- Characterisation and Correlation of Volcanism in the McArthur Basin and Transitional Domain, N.T. Proceedings The AusIMM Annual Conference, Darwin 1994, pp. 157-160. **RAWLINGS, D. J. and others, in prep- Arnhem Bay - Gove, Northern Territory - 1:250 000 Geological Map Series.  National Geoscience Mapping Accord, Explanatory Notes, SD53 -3, 4.|16-MAY-23
37728|Caulfield beds|Name source|Caulfield Clay Flats, around latitude 18o20'S longitude 137o25'E, a group of perennial clay lakes 10 km north of Wangalingi Station in the Nicholson Land Trust in MOUNT DRUMMOND.|16-MAY-23
37728|Caulfield beds|Unit history|Previously mapped as 'Fickling beds' on the first edition of MOUNT DRUMMOND by Smith and Roberts (1963). These were subsequently revised to Fickling Group (Sweet 1984).|16-MAY-23
37728|Caulfield beds|Geomorphic expression|Recessive with dark moderately banded phototones.|16-MAY-23
37728|Caulfield beds|Type section locality|Recessive outcrop along Pandanus Creek in the western Bauhinia Dome around latitude 18o6'S longitude 137o23'E in MOUNT DRUMMOND. The best outcrops are between 749500E 7994400N and 749000E 7992800N.|16-MAY-23
37728|Caulfield beds|Extent|In the Bauhinia Dome of north-central MOUNT DRUMMOND, centred on 755000E 8000000N, which is drained by Norris and Little Pandanus Creeks.|16-MAY-23
37728|Caulfield beds|Thickness range|Up to 600 m.|16-MAY-23
37728|Caulfield beds|Lithology|Dominated by yellow to red/brown lithic micaceous coarse- to very coarse-grained pebble-bearing sandstone and pebble to boulder conglomerate. These are poorly sorted with very high lithic component and a dominantly metamorphic-felsic igneous provenance. They form 0.5-8 m thick benches/beds, generally lacking internal stratification. Interbedded with coarse facies is minor fine- to medium-grained lithic sandstone and micaceous siltstone with small to medium scale trough cross-beds, planar bedding, parting lineation and interference ripples. Also interbedded (or forming allochthonous blocks) within the sequence are sandy and pebbly dolarenite, dolorudite, dololutite and dolomitic-lithic sandstone. The top 100 m of the unit comprises chertified dolostone and yellow fine+/-medium grained, quartzose to sublithic, silicified, micaceous sandstone with small trough cross-beds, planar bedding and parting lineation. Also present is flaggy, slabby, platy or shaly outcrop of red/brown to green or yellow, micaceous siltstone, fine- to very fine-grained lithic sandstone and shale. Bedding is planar or lenticular with common parallel lamination.|16-MAY-23
37728|Caulfield beds|Depositional environment|Probably marine, possibly fan-delta debris-flow and submarine talus deposits.|16-MAY-23
37728|Caulfield beds|Relationships and boundaries|Basal relationship unknown, as underlying rocks are not exposed. Unconformably but concordantly overlain by Constance Sandstone of the South Nicholson Group.|16-MAY-23
37728|Caulfield beds|Age reasons|Maximum age constrained by a lack of metamorphism and deformation of Caulfield beds (therefore younger than nearby >1845 Ma Cliffdale Volcanics basement; Page et al 2000). Minimum age constrained by correlation of the overlying Constance Sandstone with the Mesoproterozoic Roper superbasin, which is 1500-1400 Ma (Jackson et al 1999, Abbott et al 2001). Rocks above the probable equivalent of the Constance Sandstone in the Roper Group yield a date of 1493+/-4 Ma, suggesting that the Caulfield beds are around, or greater than 1500 Ma in age.|16-MAY-23
37728|Caulfield beds|Correlations|Tentatively correlated with the Crow Formation (South Nicholson Group) because it contains similar coarse-grained gravity-flow facies in the Benmara-Canyon Range area. In addition, the contact with the overlying Constance Sandstone (a probable correlative of the Mittiebah Sandstone, South Nicholson Group) is essentially concordant, and may represent a relatively minor hiatus. Correlation with the Fickling and McNamara Groups appears less likely, because they only rarely contain similar facies. However, the middle to upper McNamara Group in the Maloney Creek Inlier includes mixed coarse-grained siliciclastic and carbonate facies (Sweet 1985), and correlation with this part of the McNamara Group cannot be ruled out.|16-MAY-23
37728|Caulfield beds|Defn author|Rawlings, D.J. [aproved 11-APR-2005]|16-MAY-23
37728|Caulfield beds|Comments|The age, relationships and absolute stratigraphic position are difficult to constrain, thus necessitating the status of 'beds'. Notes: All locations are based on the GDA94 geodetic datum. Standard series 1:250 000 sheet names are shown in upper case.|16-MAY-23
37728|Caulfield beds|References|**ABBOTT S.T., Sweet I.P., Plumb K.A., Young D.N., Cutovinos A., Ferenczi P.A., Brakel A. and Pietsch B.A., 2001. Roper region: Urapunga and Roper River special, Northern Territory (Second Edition); 1:250 000 Geological Map Series, sheets SD53-10,11. Northern Territory Geological Survey-Australian Geological Survey Organisation (NGMA), Map and Explanatory Notes.  **JACKSON M.J., Sweet I.P., Page R.W. and Bradshaw B.E., 1999. The South Nicholson and Roper Groups: evidence for the early Proterozoic Roper Superbasin. In: Bradshaw B.E. and Scott D.L. (Eds.), Integrated basin analysis of the Isa Superbasin using seismic, well-log and geopotential data: an evaluation of the economic potential of the northern Lawn Hill Platform. Australian Geological Survey Organisation, Record 1999/19 (unpaginated).   **PAGE R.W., Jackson M.J. and Krassay A.A., 2000. Constraining sequence stratigraphy in north Australian basins: SHRIMP U-Pb zircon geochronology between Mt Isa and McArthur River. Australian Journal of Earth Sciences, 47, 3; 431-459.   **SMITH J.W. and Roberts H.G., 1963. Mount Drummond, N.T. (First Edition); 1:250,000 geological series, sheet SE53-12. Bureau of Mineral Resources, Geology and Geophysics, Map and Explanatory Notes.  **SWEET I.P., 1984. Carrara Range region, Northern Territory (First Edition); 1:100,000 geological series, portions of sheets 6460 and 6360. Bureau of Mineral Resources, Geology and Geophysics, Explanatory Notes.  **SWEET I.P., 1985. Relationship of the Maloney Creek Inlier to other elements of the western Lawn Hill Platform Cover, northern Australia. BMR Journal of Geology and Geophysics, 9; 329-338.|16-MAY-23
3865|Central Mount Stuart Formation|Name source|The name is derived from Central Mount Stuart (Yard grid reference: 67000E, 2263000N), the highest point in the Johns Range in the southeastern part of the Mount Peake 1:250 000 Sheet area, and situated nearly at the geographical centre of Australia.|16-MAY-23
3865|Central Mount Stuart Formation|Type section locality|A lithologic type section has been measured in two parts at Central Mount Stuart; this was necessitated by the fact that the basal unconformity is exposed at one locality in the Johns Range, whereas the top of the sequence is situated at another locality 4 km from the first and separated by a northwest-trending fault. The top most bed of the lower part of the section was traced by airphoto interpretation along strike from the southwestern block across the fault into the northeastern block, and the upper part of the section measured from there to the summit of Central Mount Stuart. The base of the lower part of the type section is at yard grid reference 675500E, 2259000N, and its top at 675200E, 2265200N; the base of the upper part of the type section is at yard grid reference 677600E, 2261800N, and its top at the summit of Central Mount Stuart, yard grid reference 677000E, 2263000N. The sequence in the type section can be divided into two main parts, a pelitic and calcareous lower unit and a psammitic upper unit each about 400 m thick. The lower unit begins with about 4 m of tillite, followed by 25 m of interbedded pebble conglomerate and limestone without conglomerate. These rocks are overlain by 25 m of purple-brown calcareous quartz sandstone and green or purple shale. These are overlain by about 220 m of interbedded greenish-grey feldspathic non-calcareous quartz sandstone and purple silty shale. The upper unit consists of about 400 m of grey-red to purple, brown feldspathic quartz sandstone, fine to medium to coarse-grained, cross-bedded, and containing abundant granules of quartz and feldspar.|16-MAY-23
3865|Central Mount Stuart Formation|Extent|The Central Mount Stuart Beds crop out over an area about 100 km by 200 km, in the Mount Peake, Barrow Creek, Alcoota, and Napperby 1:250 000 Sheet areas.|16-MAY-23
3865|Central Mount Stuart Formation|Thickness range|The thickness measured in the type section totals 800 m; elsewhere in the Mount Peake Sheet area the thickness is less than this. In the Barrow Creek Sheet area, the average thickness is about 140 m, with a maximum of about 250 m (Smith & Milligan, 1964). In the Alcoota Sheet area, the thickness is 760 m at Mount Skinner and 445 m east of there (estimated from magnetic data, Shaw et al., in prep.) In the Napperby Sheet area, the thicknesses of the various outliers are estimated at about 150 m (Evans & Glikson, 1969).|16-MAY-23
3865|Central Mount Stuart Formation|Lithology|The Central Mount Stuart Beds are a dominantly red-bed sequence comprising several different rock-types. In the Mount Peake 1:250 000 Sheet area, it consists of either local tillite, or arkosic conglomerate, or calcareous pelite at the base, overlain respectively by grey or yellow pelite, grey arkose, or red-brown coarse feldspathic quartz sandstone. In the eastern part of the Mount Peake 1:250 000 Sheet ara, the Beds begin with a distinctive orthoquartzite (the Amesbury Quartzite Member; see attached submission) about 20 m thick, and this is overlain by feldspathic quartz sandstone. In the Barrow Creek 1:250 000 Sheet area, the Beds begin with brown silty sandstone, siltstone, and pebble conglomerate, followed by red arkose, sandstone, and greywacke, with interbeds of siltstone and rare dolomite (Smith & Milligan, 1964). In the Alcoota 1:250 000 Sheet area, the Beds comprise (i) a local basal unit of grey or white feldspathic quartz sandstone with lenses of conglomerate, (ii) a thick extensive unit of red lithic feldspathic quartz sandstone and shale with calcareous sandstone at the base and dolomite near the base, plus some grey sandstone and siltstone interbeds, and (iii) an upper unit of quartz sandstone and feldspathic quartz sandstone (Shaw et al., in prep.). In the Napperby 1:250 000 Sheet area, the Beds form a few isolated outliers, variously consisting of feldspathic quartz sandstone, conglomerate, tillite, and siltstone (Evans & Glikson, 1969).|16-MAY-23
3865|Central Mount Stuart Formation|Relationships and boundaries|In the Mount Peake and Napperby 1:250 000 Sheet areas, the Central Mount Stuart Beds rest unconformably on granite or amphibolite of the Arunta Block, and the unconformity is well exposed at numerous localities; no unit overlies the Beds in these Sheet areas, and the top of the Beds is eroded. In the Barrow Creek 1:250 000 Sheet area, the Central Mount Stuart Beds rest unconformably on granite and metamorphic rocks of the Arunta Block, and are conformably overlain by a formation which contains Early Cambrian fossils (Smith & Milligan, 1964). The nature of the lithological change and how it is distinguished in the field are not described by Smith & Milligan, nor by Smith (1972), and the area in question has not been visited by us; presumably the change in lithological characteristics from red thick-bedded arkose and medium-bedded sandstone and greywacke of the Central Mount Stuart Beds to brown, grey, or red glauconitic quartz sandstone and brown or white siltstone of the overlying formation is fairly apparent. The overlying unit was designated as Grant Bluff Formation by Smith & Milligan, but later work by Shaw et al. (in prep.) has shown that this unit is lithologically more similar to the Mount Baldwin Formation, which also contains Early Cambrian fossils and conformably overlies the Grant Bluff Formation in the Huckitta 1:250 000 Sheet area. Drilling near Mount Skinner in the Alcoota 1:250 000 Sheet area found that the Grant Bluff Formation underlies the Central Mount Stuart Beds. On the other hand, Shaw et al. state that the grey sandstones in the Central Mount Stuart Beds in the Alcoota Sheet area are not unlike similar beds in the Grant Bluff Formation, and we have noted that various rock types in the lower part of the Central Mount Stuart Beds and in the upper part of the Grant Bluff Formation (in the Elyuah Range of the Huckitta Sheet area) are lithologically similar to each other and to certain members of the Pertatataka Formation in the Amadeus Basin to the south. It thus appears that the lower part of the Central Mount Stuart Beds is a facies equivalent of the upper part of the Grant Bluff Formation. Shaw et al. also suggest that the boundary of the Central Mount Stuart Beds and Grant Bluff Formation may be time-transgressive, i.e., it rises up section to the south and brings the Grant Bluff Formation directly underneath the Mount Baldwin Formation. In the Alcoota 1:250 000 Sheet area, the Central Mount Stuart Beds are juxtaposed against the Upper Cambrian to Lower Ordovician Tomahawk Beds, but the contact is obscured by alluvium; a fault with a displacement of about 1.5 km may exist, but Shaw et al. believe that an unconformable on-lapping relationship of Tomahawk Beds on to Central Mount Stuart Beds is more likely.|16-MAY-23
3865|Central Mount Stuart Formation|Identifying features|Reason for proposed name: The unit was originally named the Central Mount Stuart Beds by Smith & Milligan (1964). However, field mapping in 1974 located several excellent exposures of the lower boundary of the Beds, and the upper boundary coincides with the base of a conformably overlying formation in the Barrow Creek 1:250 000 Sheet araea. Hence, we wish to redefine the Beds as the Central Mount Stuart Formation. Furthermore, a type section has been measured at Central Mount Stuart, where the base is well exposed, and a minimum thickness established there (the top being eroded).|16-MAY-23
3865|Central Mount Stuart Formation|Age reasons|The existence of tillite in the lower part of the Central Mount Stuart Beds indicates an Adelaidean age for this part of the formation, and the presence of worm burrows, bilobate tails, and other trace fossils in the upper part of the unit indicates a very early Cambrian age (Glaessner, 1969; Daily, 1974). Hence, the Central Mount Stuart Beds straddle the Precambrian-Cambrian boundary.|16-MAY-23
26298|Chabalowe Formation|Name source|After Chabalowe bore in Barrow Creek !:250 000 Sheet area at AMG reference MS619500.|16-MAY-23
26298|Chabalowe Formation|Unit history|Previously included in the Tomahawk beds by Smith and Milligan (1964 and 1966).|16-MAY-23
26298|Chabalowe Formation|Type section locality|Holostratotype: In NTGS BC5, from 166.90 to 327.43 m. The collar locality is AMG reference MS156765 in Barrow Creek 1:250 000 Sheet area (latitude 21o0'44"S, longitude 134o11'16"E). Shows 36 m of conglomerate and sandstone at the base, overlain by 160 m of typical lithology (sandstone, dolostone). The top is identified by gradation from sandstone-dominant to carbonate-dominant sequence, the base by unconformity on Proterozoic granite.  Parastratotype: In NTGS ELK7, 7A from 15.00 to 238.05 m. The collar locality is AMG reference NS 162052 in Elkedra (latitude 21o39.5'S, longitude 135o9.5'E). Top is not exposed, upper 153 m is similar to holostratotype, lower 95 m constitutes gypsum-rich beds and dolostone of the Hagen Member. Base is identified by gradation into dark carbonaceous and fossiliferous dolarenites and dolomitic siltstone of Arthur Creek Formation.  Reference locality: About 8.5 km south-southeast of Chabalowe bore around AMG reference MS657422 in Barrow Creek. Poorly exposed as low rises of ferruginised sandstone minor chert and very rare dolostone. No formation boundaries seen on the ground surface.|16-MAY-23
26298|Chabalowe Formation|Extent|Crops out over 90 km in distance between Chabalowe bore in Barrow Creek and Honeymoon bore on Elkedra; intersected in NTGS diamond drillholes ELK6, 7 and 7A and BC 3 and 3A and 5 (all core is stored in the NTGS core store in Alice Springs).|16-MAY-23
26298|Chabalowe Formation|Thickness range|The maximum known thickness is 300 m in NTGS DDH ELK6. The collar locality is AMG reference NR 051740.|16-MAY-23
26298|Chabalowe Formation|Lithology|The lithology of the holostratotype NTGS DDH BC5 is summarised below.  39.50 m (166.00-205.50m). Sandy dolarenite and dolomitic sandstone with minor interbeds of mudstone and dolomicrite.  85.03 m (205.5-290.53 m). Dolomitic sandstone, in party sandy dolostone and rare dolarenite; minor interbeds of dolomicrite, dololutite, algal dolostone, partly micaceous and carbonaceous siltstone and rare intraformational breccia.  24.24 m (290.53-314.77 m). Granule to pebble conglomerate with granitic, metavolcanic and metaquartzite clasts in a sandy dolostone to dolomitic arkose matrix, sandstone with minor dolomite in matrix, minor dolarenite.  12.66 m (314.77-327.43 m). Conglomerate with granitic pebble clasts and minor metasediment and metavolcanic clasts, the matrix is a lithic arenite. This rests unconformably on a poorly foliated coarse-grained Proterozoic granite.  The lithology of the parastratotype NTGS DDH ELK7, 7A is described below. ELK7 ends at a depth of 71.75 m and ELK 7A begins at 65.61 m. Open hole above 15m. 31.33 m (15-46.33 m) Interbedded in part dolomitic siltstone, claystone and fine-grained sandstone; minor medium- to coarse-grained sandstone.  31.48 m (46.33-77.81 m) Interbedded dolomite, claystone and siltstone; minor fine- to medium-grained sandstone and intraformational breccia.   35.84 m (77.81-113.64 m) Fine- to medium-grained, porous sandstone with a dolomitic matrix in part, dolomite with chert nodules, algal laminate, dolarenite, claystone, siltstone and intraformational breccia. 39.48 m (113.64-153.48 m) Dolarenite, algal laminate, dolomite with chert nodules, dololutite, fine-grained sandstone, intraformational breccia.  The Hagen Member of the Chabalowe Formation begins at 153.48 m and ends at 248.76 m.  15.83 m (153.48-169.31 m) Interbedded gypsum, gypsiferous siltstone and chert (silicified algal laminate), minor anhydrite.  3.89 m (169.31-173.20 m) Dolostone, algal laminate and fine-grained dolarenite; minor dololutite.  9.38 m (173.20-182.58 m) Massive gypsum (satin spar) interbedded with siltstone, chert and dolostone, minor anhydrite.  55.47 m (182.58-238.05 m) Dolostone, in part stromatolitic, dolorudite, dolarenite, dololutite, intraformational breccia.  10.71 m (238.05-248.76 m) Dolostone silty grainstone, dolomitic siltstone.  Below 248.76 m is the Arthur Creek Formation.|16-MAY-23
26298|Chabalowe Formation|Relationships and boundaries|Unconformable on Proterozoic granite and the Hatches Creek Group in Barrow Creek; in part laterally equivalent to and gradationally overlies the Templetonian Arthur Creek Formation in Elkedra; gradationally overlain by the Arrinthrunga Formation in Barrow Creek and Elkedra. In ELK6 and 7A contains a basal lensoidal grainstone shoal and sabkha unit defined as the Hagen Member.|16-MAY-23
26298|Chabalowe Formation|Age reasons|Middle Cambrian based on lateral relationship with the Templetonian Arthur Creek Formation.|16-MAY-23
27739|Chandler Formation|Name source|The name Chandler was first used by Ranford et al (1965) and although not specifically referred to it it thought to be derived from the Chandler Range which is 110 km southwest of Alice Springs.|16-MAY-23
27739|Chandler Formation|Unit history|Previously referred to as the Chandler Limestone by Ranford et al. (1965).|16-MAY-23
27739|Chandler Formation|Type section locality|This remains the same as inferred by Ranford et al. (1965), 10 kms north-east of Tempe Downs homestead (24o20'54" 132o29'50"). Its thickness can not be determined due to repetition of the sequence by thrust faulting and salt tectonics. An additional reference section occurs at Three Mile Waterhole on the Finke River, 10 km northwest of Henbury homestead (24o31'06" 133o13'03"). It has better access and exposure than the type section, and clearly shows the involvement of thrust faulting and salt tectonics typical of the unit.|16-MAY-23
27739|Chandler Formation|Extent|Originally it was mapped in the east and central-east parts of the basin (Wells et al. 1970). It has been extended to the central-west part of the Amadeus Basin in the Gardiner Range, West Petermann Creek and Parana Hill Anticlines (Bradshaw, in prep.). Previously this had been described as a lens at the base of the Tempe Formation (Ranford et al, 1965), but detailed studies and drilling (Hermannsburg #41) shows it to be continuous and separated by a disconformity and erosion surface from the Tempe Formation.|16-MAY-23
27739|Chandler Formation|Thickness range|In Camel Flat Syncline it is 670 m thick (Bluebush #1) with an average of 470 m, although it ranges up to >1000 m on seismic profiles (due to salt flowage). In Orange Creek Syncline it is 263 m thick (Gingo #2) with an average thickness of 225 m. In outcrop the carbonate lithofacies is only 5-10 m thick, although due to intense salt flowage and thrusting, the sequence is often repeated 5 or 6 times giving the appearance of a thick unit. This agrees with the central-west area where no salt is present and the carbonate is 15 m thick.|16-MAY-23
27739|Chandler Formation|Lithology|Petroleum drilling has shown that the "Chandler Formation" is dominated by evaporites (Camel Flat Syncline-Bluebush #1). The evaporite minerals are mostely halite (>95%), with minor gypsum and sulphur. In the Orange Creek Syncline the sequence is (approx. 225 m thick, comprising 185 m of halite and 40 m of red siltstone, shale and dark grey foetid carbonate. The carbonate (from which the unit was originally named) is a mixture of limestone and dolomite in the eastern and central-east part of the basin, and is completely dolomitised in the central west. The carbonate is the only lithology to crop out.|16-MAY-23
27739|Chandler Formation|Depositional environment|Bromine analysis of the halite suggests it was derived from a marine source. The foetid carbonate is subtidal, and has no shallow water indicators.|16-MAY-23
27739|Chandler Formation|Relationships and boundaries|In the central-west the Chandler Formation disconformably overlies the Arumbera Sandstone and Namatjira Formation, and unconformably overlies the Areyonga and Bitter Springs Formations. In the eastern part of the basin it overlies all of the older units in the basin. The contacts are all structurally modified (due to salt tectonics and dissolution), but are believed to be at least disconformable and often are an unconformable relationship.|16-MAY-23
27739|Chandler Formation|Age reasons|No fossils have been found, except for algal remains which are not age diagnostic. It is considered to be Early Cambrian in age.|16-MAY-23
3971|Chewings Range Quartzite|Name source|Chewings Range in Alice Springs, MacDonnell Ranges and Hermannsburg 1:100 000 Sheet areas; composed of the unit.|16-MAY-23
3971|Chewings Range Quartzite|Type section locality|Along Jay Creek in Alice Springs 1:100 000 Sheet area. GR 5650-512808 to 508819.|16-MAY-23
3971|Chewings Range Quartzite|Extent|Makes up the Chewings Range which extends from about Mt Lloyd in Alice Springs 1:100 000 Sheet area westwards to near Mt Giles in Hermannsburg 1:100 000 Sheet area.|16-MAY-23
3971|Chewings Range Quartzite|Lithology|Interlayered metaquartzite and muscovite-quartz schist, and a small amount of staurolite-garnet-mica schist.|16-MAY-23
3971|Chewings Range Quartzite|Relationships and boundaries|Unconformably overlain by Heavitree Quartzite. Underlain to the south by the Simpsons Gap Metasediments (new name). May be underlain to the north by orthogneiss. In MacDonnell Ranges 1:100 000 Sheet area the unit extends into the basement gneiss with apparent conformity. Dolerite dykes of the Stuart Dyke Swarm intrude the unit.|16-MAY-23
3971|Chewings Range Quartzite|Identifying features|Reason for proposed name: The term Chewings Range Quartzite has been published previously but never defined in the strict sense.|16-MAY-23
3971|Chewings Range Quartzite|Age reasons|Older than the Late Proterozoic Heavitree Quartzite which overlies it and the dolerite dykes which intrude it. Metamorphosed during the Chewings Phase of deformation at 1620 +/- 70 m.y.|16-MAY-23
3971|Chewings Range Quartzite|Proposed publication|Geological report on the 1:100 0000 scale mapping of southeastern Arunta Block, Alice Springs 1:250 000 Sheet area, Northern Territory by R.D. Shaw et al. BMR.  Microfiche report in prep.|16-MAY-23
79227|Chookla Member|Name source|Chookla Well (abandoned) in southwestern HENBURY 1:250 000 (WALLERA 1:100 000), 132.2586deg E, -24.8312deg S.|16-MAY-23
79227|Chookla Member|Geomorphic expression|Boulder fields of large pebbles, cobbles and boulders on hill and ridge slops and low-lying areas and associated rounded hills and flat-topped ridges where clast-supported conglomerate is typically exposed.|16-MAY-23
79227|Chookla Member|Type section locality|Type Area: eroded hills at GDA94 53J 231322 mE, 7235797 mN approximately 9.5 km SW of Angus Hill (GDA94 53J 236571 mE, 7242276 mN). Reference Area: small ridge of the southeastern Liddle Hills at GDA94 53J 229560 mE, 7242850 mN|16-MAY-23
79227|Chookla Member|Extent|Currently mapped in central and southwestern HENBURY 1:250 000. Its regional extent is not yet known but it likely extends at least into LAKE AMADEUS and BLOODS RANGE 1:250 000 mapsheets.|16-MAY-23
79227|Chookla Member|Thickness range|True thickness is not known due to poor exposure and erosion of the matrix allowing the gravitational transport of the clasts beyond the true extent of the unit. Where the unit is crudely stratified, such as in the type area, the unit is at least 100 m thick, however in the reference area the unit is estimated to be at least 30 m thick. So, apparent thickness from at least 100 m to 30 m in southwestern HENBURY 1:250 000.|16-MAY-23
79227|Chookla Member|Lithology|Type area: Conglomerate. Generally exposed as residual rounded pebbles, cobbles and small boulders of quartz arenite, subarkose and vein quartz without matrix. Coarse-grained to granular, poorly-sorted sandstone is locally exposed. Relict clay indicates a significant original feldspar content which indicates these sandstones are arkosic. A similar composition is inferred for the matrix to the conglomerate. At reference area, Chookla Member is observed in contact with Puna Kura Kura Formation. The clast-supported conglomerate has rounded pebbles, cobbles and small boulders of quartz arenite, subarkose and vein quartz within a poorly sorted matrix of  very coarse-grained purple-red sandstone with clay and Fe-oxide mineral cement. Occasional weathered mica and feldspar grains are also observed within the matrix.|16-MAY-23
79227|Chookla Member|Depositional environment|Molasse-type sedimentary rock potentially deposited in response to uplift  related to the 580-530 Ma Petermann Orogeny.|16-MAY-23
79227|Chookla Member|Diastems or hiatuses|Not known.|16-MAY-23
79227|Chookla Member|Relationships and boundaries|Overlies or partially incised into Puna Kura Kura Formation. Where apparent upper contact is poorly exposed, for example in the reference area, it is transitional with clasts become increasingly sparse and the sandstone matrix becoming increasingly stratified.|16-MAY-23
79227|Chookla Member|Identifying features|Abundant rounded, large boulders and cobbles of quartz arenite, subarkose and vein quartz are typically scattered on hill slopes and low lying areas. Exposures that are topographically above these boulder fields often contain sparse outcrop of clast-supported conglomerate amongst loose boulders and cobbles.|16-MAY-23
79227|Chookla Member|Structure and Metamorphism|Folded and faulted, but unmetamorphosed.|16-MAY-23
79227|Chookla Member|Age reasons|Potential correlation with other 580-530 Ma Petermann Orogeny molasse-type deposits suggests a late Ediacaran to Early Cambrian age.|16-MAY-23
79227|Chookla Member|Correlations|Probably correlates with Quandong Conglomerate of Ranford et al (1965), and in turn with the Arumbera Sandstone (Wells et al 1970). Edgoose et al (1993) correlated a thin interval of conglomerate in the early Cambrian succession in the Erldunda Range in KULGERA with Quandong Conglomerate. Inferred equivalence to the Mount Currie Conglomerate and Mutitjulu Arkose (cf Edgoose 2013) and also therefore likely with the Sir Frederick Conglomerate (cf Haines et al 2010).|16-MAY-23
79227|Chookla Member|Geophysical Expression|Generally linear, low total Magnetic intensity typical of Winnall Group.|16-MAY-23
79227|Chookla Member|Defn author|Donnellan N and Normington VJ, MAR-2017|16-MAY-23
79227|Chookla Member|References|Edgoose CJ, 2013. Amadeus Basin: in Ahmad M and Munson TJ (compilers). 'Geology and mineral resources of the Northern Territory', Northern Territory Geological Survey, Special Publication 5.***Edgoose CJ, Camacho A, Wakelin-King GA and Simons BA, 1993. Kulgera, Northern Territory, 1:250 000 geological map series explanatory notes, SG 53-05. Northern Territory Geological Survey, Darwin. ***Haines PW, Allen HJ and Grey K, 2010. Reassessment of the geology and exploration potential of the Western Australian Amadeus Basin. IN GSWA 2010 extended abstracts: promoting the prospectivity of Western Australia. Geological Survey of Western Australia, Record 2010/2, p27-29.  ***Ranford  LC, Cook PJ and Wells AT, 1965. The geology of the central part of the Amadeus Basin, Northern Territory. Bureau of Mineral Resources, Australia, Report 86. ***Wells AT, Forman DJ, Ranford LC and Cook PJ, 1970. Geology of the Amadeus Basin, Central Australia. Bureau of Mineral Resources, Australia, Bulletin 100.|16-MAY-23
21509|Coast Range Sandstone|Name source|Coast Range (latitude 13030'S, longitude 135o48'E), Blue Mud Bay 1:250 000 scale map sheet area.|16-MAY-23
21509|Coast Range Sandstone|Unit history|Formally mapped as part of the now abandoned 'Groote Eylandt Beds' (Plumb and Roberts, 1965).|16-MAY-23
21509|Coast Range Sandstone|Geomorphic expression|Prominent, joint-controlled, bare rocky outcrops.|16-MAY-23
21509|Coast Range Sandstone|Type section locality|Northern Coast Range at latitude 13o24'S, longitude 135o50'E, about 1 km east of the point where the only access track first meets the range. Lower boundary stratotype at AMG NF905180 and upper boundary stratotype top at AMG NG902180. This is the most accessible location with top and bottom exposed, and demonstrates all major subunits recognised in the area.|16-MAY-23
21509|Coast Range Sandstone|Extent|Eastern Blue Mud Bay 1:250 000 scale map sheet area. Crops out at Coast Range, Mount Grindall, Round Hill Island, unnamed peninsula west of Jalma Bay and near Gan Gan community.|16-MAY-23
21509|Coast Range Sandstone|Thickness range|Estimated to be about 30-40 m thick in the Mount Grindall area. About 20 m or less along Coast Range including type section. Locally removed by the unconformity at the base of the Jalma Formation near the southern end of Coast Range.|16-MAY-23
21509|Coast Range Sandstone|Lithology|White, medium- to coarse-grained, thick-bedded, quartz-rich sandstone. Local lower unit of pale brown, poorly sorted, coarse- to very coarse-grained sandstone and granule conglomerate at type section. Commonly pebbly, with a lenticular basal pebble or cobble conglomerate.|16-MAY-23
21509|Coast Range Sandstone|Depositional environment|Shallow marine, high energy, transgressive unit.|16-MAY-23
21509|Coast Range Sandstone|Relationships and boundaries|Not assigned to any group. Lies unconformably on the Grindall Formation, Bradshaw Complex, unnamed porphyritic felsic dykes, and unnamed felsic volcanic unit. Boundary picked at marked angular unconformity below basal conglomerate or pebbly sandstone. Inferred to overlie the Woodah Sandstone near Grindall Point (nature of contact unknown). Overlain unconformably by the Jalma Formation. Top picked below the sudden incoming of fine-grained, flaggy sandstone of the Jalma Formation (type section), or locally below basal cobble conglomerate of that formation (south end of Coast Range). Intruded by mafic dykes.|16-MAY-23
21509|Coast Range Sandstone|Age reasons|Probably late Palaeoproterozoic given tentative constraints provided by older and younger units. A maximum constraint is provided by the older porphyritic felsic dykes which are tentatively correlated on petrologic and geochemical grounds with the 1700-1710 Ma felsic suite of Rawlings (1994). The overlying Jalma Formation is tentatively correlated with the Balma Group, the top of which is dated at ~1600 Ma (Pietsch and others, 1994).|16-MAY-23
21509|Coast Range Sandstone|Correlations|Tentatively correlated with the Parsons Range Group based on lithology and stratigraphic position.|16-MAY-23
21509|Coast Range Sandstone|Proposed publication|Blue Mud Bay 1:250 000 Geological Map Series, Northern Territory, National Geoscience Mapping Accord, Explanatory Notes, SD 53-7 (Haines and others, in prep.).|16-MAY-23
37963|Cockroach Group|Name source|From Cockroach Waterhole and Cockroach Bore in central TOBERMORY, within the corridor of interdigitation of Tomahawk Formation and Ninmaroo Formation.|16-MAY-23
37963|Cockroach Group|Unit history|Ninmaroo Limestones and Ninmaroo Series of Whitehouse (1936); lower portion of Dulcie Sandstone of Joklik (1955) in part; Gola beds (Casey 1959) in part; major portion of Tomahawk beds of Smith (1964) in part.|16-MAY-23
37963|Cockroach Group|Constituents|Chatsworth Limestone, Ninmaroo Formation, Tomahawk Formation, Swift Formation.|16-MAY-23
37963|Cockroach Group|Extent|BARROW CREEK, ALCOOTA, ELKEDRA, HUCKITTA, SANDOVER RIVER, TOBERMORY, HAY RIVER, MOUNT WHELAN, GLENORMISTON, URANDANGI, BOULIA, DUCHESS.|16-MAY-23
37963|Cockroach Group|Relationships and boundaries|Chatsworth Limestone conformably and gradationally overlies Pomegranate Limestone of Narpa Group. Where Chatsworth Limestone is absent, Cockroach Group is disconformable on Arrinthrunga Formation, Georgina Limestone and Mungerebar Limestone of Narpa Group. Conformably to locally disconformably overlain by Kelly Creek Formation of Toko Group or where this is absent, unconformably overlain by Mesozoic sedimentary rocks (Casey 1959, Shergold et al 1976, 1985).|16-MAY-23
37963|Cockroach Group|Age reasons|Fauna (particularly of trilobites and conodonts) indicates medial Late Cambrian (medial Iverian) to early Early Ordovician (late Warendian) to possibly medial Early Ordovician (Bendigonian) (Skwarko 1968, Shergold and Nicoll 1992)|16-MAY-23
37963|Cockroach Group|Correlations|Upper Goyder Formation and Pacoota Sandstone of Amadeus Basin, Djagamara Formation of Ngalia Basin (Webby et al 1981, Shergold et al 1985).|16-MAY-23
37963|Cockroach Group|Comments|The Swift Formation is included in the group as it is regarded by Shergold et al (1976) and Druce et al (1982) as a subaerial regolith discordant on uppermost Ninmaroo Formation. The upper extent of the Cockroach Group is therefore diachronous: late Warendian or Bendigonian atop Ninmaroo Formation-Swift Formation to the east, but latest Late Cambrian (late Datsonian) atop Tomahawk Formation to the west (Shergold and Druce 1980:161, Jones et al 1971:21, Shergold and Nicoll 1992). A putative Early Ordovician fauna listed from Tomahawk Formation by Laurie (2000f) is stratigraphically below uppermost Tomahawk Formation limestone bearing Datsonian conodonts.|16-MAY-23
35509|Collara Subgroup|Type section locality|Type area: As for the whole Roper Group, most type sections for individual formations are in the URAPUNGA sheet in the Roper River area, although some (eg Mantungula Formation) are further to the south. The southern URAPUNGA area is the best studied and is therefore the most appropriate type area for the Subgroup. See the type sections of the constituent formations: Phelp Sandstone, Mantungula Formation, Limmen Sandstone, Mainoru Formation, Crawford Formation, Arnold Sandstone, Jalboi Formation and Hodgson Sandstone.|16-MAY-23
83006|Confusion Dam Formation|Name source|Confusion Dam Formation is named after Confusion Dam (GDA94, 53K, 637535mE, 7831020mN), approx. 10 km south of type intersection.|16-MAY-23
83006|Confusion Dam Formation|Geomorphic expression|No known outcrops.|16-MAY-23
83006|Confusion Dam Formation|Type section locality|Drillhole NDIBK04, down-hole depth from 236 m to 416 m. Drillhole location 635380mE 7839553mN (MGA94 zone 53) / 19.534200S 136.290361E. Drill core is stored at the NTGS core library in Alice Springs.|16-MAY-23
83006|Confusion Dam Formation|Description at type locality|Dark- to light-grey banded phyllite and massive graphitic phyllite. Schistose in parts. Minor intervals of carbonate. Banding is generally several mm thick, with the darker bands containing more graphite than the lighter bands. Lighter bands may also contain more quartz. Sulfides (pyrite and pyrrhotite) are locally abundant and, in some cases, occur along bedding planes but are more commonly associated with structural features (see below).|16-MAY-23
83006|Confusion Dam Formation|Extent|Unknown. Although the geophysical expression of this unit at the type intersection is distinct, particularly in magnetics imagery (see below), this reflects subsequent alteration that is not necessarily unique to this unit and therefore shouldn?t be used to determine the true extent of the Confusion Dam Formation as defined here. Other drillholes in the region intersect rocks that are younger than this unit, so its true extent is unconstrained, and it may extend widely underneath the Alroy Formation throughout the East Tennant region. Furthermore, undated lithologies in other drillholes in the region (e.g. in drillhole DD80 AL3 and carbonaceous intervals in drillhole DDH005) may be equivalent to the Confusion Dam Formation, which would demonstrate a more widespread extent for this unit.|16-MAY-23
83006|Confusion Dam Formation|General description|Only known in type interval. See description above.|16-MAY-23
83006|Confusion Dam Formation|Thickness range|180 m. Bottom of unit is not intersected and the total thickness of this unit is likely much greater than the value indicated here.|16-MAY-23
83006|Confusion Dam Formation|Lithology|Dark- to light-grey banded phyllite, massive graphitic phyllite, and subordinate carbonate rocks.|16-MAY-23
83006|Confusion Dam Formation|Depositional environment|Laminated carbonaceous sediments suggest that the Confusion Dam Formation was deposited under quiescent conditions in a restricted basin.|16-MAY-23
83006|Confusion Dam Formation|Relationships and boundaries|Any primary relationship between this unit and overlying Kerringnew Formation is difficult to determine due to deformation and metamorphism. Bottom of this unit is not exposed.|16-MAY-23
83006|Confusion Dam Formation|Identifying features|The banded graphitic character of this unit distinguishes it from most intersections of the Alroy Formation, although graphitic intervals are also present within the latter (e.g. in drillhole DDH005). Detrital zircon data from the Confusion Dam Formation, which are characterised by a single population of ca. 1970 Ma zircon, are strikingly different to all Alroy Formation detrital zircon spectra and are therefore also considered a distinguishing feature of the Confusion Dam Formation (see further discussion on the significance of this detrital zircon data in Age & Evidence and Comments below).|16-MAY-23
83006|Confusion Dam Formation|Structure and Metamorphism|Unit is steeply-dipping, folded and metamorphosed. The protolith of this unit is interpreted to have been a sequence of graphitic siltstone and mudstones. Folds are tight to isoclinal and associated with a well-developed foliation that parallels fold axial surfaces and dips steeply to the northwest. Hinges of folds are often sheared out along this foliation, resulting in the widespread development of a composite fabric comprising this shear foliation together with transposed bedding surfaces. Quartz veins, often associated with pyrite and/or pyrrhotite, are locally abundant. They locally cross-cut foliation, but are also boudinaged and sheared so that they are sub-parallel to, and help define this fabric. Sulfides are associated with bedding surfaces, veins, and the regional shear foliation. They are commonly present within the strain shadows of garnet porphyroclasts. Regardless of the origin of the sulfur, it has been significantly re-mobilised during deformation.  Common metamorphic minerals are muscovite, garnet, chloritoid, andalusite and biotite. Chloritoid and andalusite include a subtle foliation, but are also wrapped, along with garnet, by the main foliation, which is defined by dynamically recrystallised quartz, muscovite and biotite grains. Chlorite is present only as a rare, retrograde phase. These observations suggest that metamorphism occurred at lower amphibolite-facies conditions and was associated with significant deformation.The structures and metamorphic assemblages mentioned above are overprinted by less abundant close folds and brittle-ductile faults and veins. These structures are associated with minor Cu mineralisation in the type interval.|16-MAY-23
83006|Confusion Dam Formation|Age reasons|A sample from the Confusion Dam Formation returned a unimodal zircon U-Pb age population (nine analyses) with a U-Pb detrital zircon maximum deposition age of 1969 +/-10 Ma (Kositcin et al., in prep). The unimodal age population and absence of abrasion of zircon from the Confusion Dam Formation is interpreted to indicate a possible tuffaceous origin, with the maximum depositional age approaching the true depositional age of this unit (Kositcin et al., in prep.).|16-MAY-23
83006|Confusion Dam Formation|Alteration and Mineralisation|Cu mineralisation is known from this unit in drill core NDIBK04. The unit also contains locally abundant pyrite and pyrrhotite that is often associated with quartz veins and the dominant foliation described above.|16-MAY-23
83006|Confusion Dam Formation|Geophysical Expression|The only known drill-hole intersections of this unit is characterised by highly-elevated and variable magnetic susceptibilities in down-hole magnetic data due to the presence of pyrrhotite. This is the source of a large anomaly in regional magnetics imagery that extends for approximately 20 km along a regional structure, the Lamb Fault. However, these characteristics are the product of local alteration that is not characteristic of the unit more regionally.|16-MAY-23
83006|Confusion Dam Formation|Defn author|A.D. Clark 24-Mar-2022.|16-MAY-23
83006|Confusion Dam Formation|Proposed publication|Schofield and Clark et al., (in prep). Geology of the East Tennant area, Northern Territory, journal publication.|16-MAY-23
83006|Confusion Dam Formation|Comments|The Confusion Dam Formation is largely defined on the basis of relatively poor, but geologically significant detrital zircon U-Pb age data. Detrital zircon data from numerous samples of the Alroy Formation ubiquitously feature a dominant zircon age population at ca. 1870 Ma and various subordinate older populations into the Archean (Kositcin et al., in prep.). Although the population from the Confusion Dam Formation comprises only nine analyses and is also present in some samples of the Alroy Formation, it represents only a minor fraction (only 1?4 zircons) of the total zircon population in the Alroy Formation samples, which makes the nine analyses significant (Kositcin et al., in prep.). As noted above, the ca. 1970 Ma maximum deposition age for the Confusion Dam Formation is interpreted to approximate the timing of deposition of this unit (Kositcin et al., in prep). Detrital zircon from the overlying Kerringnew Formation also differ significantly from the Alroy Formation, with 85 analyses of zircon from a sample of the former defining a maximum deposition age of 1894 ? 3.4 Ma, with a single additional analysis overlapping with the ca. 1970 Ma age population from the Confusion Dam Formation (Kositcin et al., in prep.). Zircons from the Kerringnew Formation also showed little signs of sedimentary abrasion and are interpreted as potentially tuffaceous, which would also constrain the age of this unit to be older than the Alroy Formation (Kositcin et al., in prep.). The above information provides evidence that the basement rocks in drillhole NDIBK04 are significantly older than the Alroy Formation, and that it would be appropriate to name them as distinct stratigraphic units.|16-MAY-23
83006|Confusion Dam Formation|References|Kositcin, N., Cross A.J., et al., in prep. Geochronology of the East Tennant area, Geoscience Australia record.|16-MAY-23
24221|Coniston Schist|Name source|Coniston homestead (5453-448492), northwestern part of Reynolds Range 1:100 000 Sheet area.|16-MAY-23
24221|Coniston Schist|Unit history|Distinctive and easily mapped unit; referred to as Pine Hill Conglomerate by Australian Geophysical (1967); mapped as 'Precambrian Schist, metasediments, including marble' by Wells & others (1971).|16-MAY-23
24221|Coniston Schist|Type section locality|5453-652400, clear exposures in creek bed, 7 km southwest of Lander Bore.|16-MAY-23
24221|Coniston Schist|Extent|From Mount Thomas to northwestern end of Reynolds Range; small outcrops in Giles Range.|16-MAY-23
24221|Coniston Schist|Lithology|Small augen of quartz (with magmatic resorption embayments) and rare feldspar in fine-grained schistose matrix of muscovite and quartz.|16-MAY-23
24221|Coniston Schist|Relationships and boundaries|Lies between basal conglomerate and overlying main quartzite of Mount Thomas Quartzite; in places contains lenticular fragments up to 20 cm long of quartzite and sandstone.|16-MAY-23
24221|Coniston Schist|Age reasons|Middle Proterozoic or older|16-MAY-23
24221|Coniston Schist|Proposed publication|2. Commentary on geology of Reynolds Range Region (BMR).|16-MAY-23
68733|Connellys Volcanics|Name source|Connellys Waterhole, on Buddycurrawa Creek, near latitude 18o07'S longitude 137o08'E, a tributary to the Nicholson River in MOUNT DRUMMOND and CALVERT HILLS.|16-MAY-23
68733|Connellys Volcanics|Unit history|Previously mapped within (ie not differentiated from) the Murphy Metamorphics on the first editions of MOUNT DRUMMOND (Smith and Roberts 1963) and CALVERT HILLS (Roberts et al 1963).|16-MAY-23
68733|Connellys Volcanics|Geomorphic expression|Recessive with white or dark red/brown phototones.|16-MAY-23
68733|Connellys Volcanics|Type section locality|Type area: Low discontinuous exposures in the vicinity of latitude 18oS longitude 136o58'E (710000E 8007000N).|16-MAY-23
68733|Connellys Volcanics|Extent|Exposed in a small area near latitude 18oS longitude 136o58'E of the Canyon Range (newly approved by place names committee) at the boundary of northern MOUNT DRUMMOND and southern CALVERT HILLS.|16-MAY-23
68733|Connellys Volcanics|Thickness range|Unknown.|16-MAY-23
68733|Connellys Volcanics|Lithology|Red/brown 'brick' coloured, altered/weathered porphyritic rhyolite or rhyodacite, which generally has a mottled and highly weathered appearance that Rawlings et al (in prep) have termed 'redrock'.|16-MAY-23
68733|Connellys Volcanics|Relationships and boundaries|Field relationships cannot demonstrate an extrusive origin for the Connellys Volcanics and there are no preserved microscopic textures indicative of a pyroclastic or lava mode of emplacement.  The boundary of the Murphy Metamorphics and Connellys Volcanics is very poorly exposed, the best locality being 707400E 8009250N, where there is a juxtaposition of 'redrock' (Connellys Volcanics) and grey psammitic schist (Murphy Metamorphics). In the contact zone, 'redrock' becomes progressively more foliated westwards over a few tens of metres and grades into schist. The Connellys Volcanics are unconformably overlain by various units, including the Breakfast Sandstone (Benmara Group) and Bowgan Sandstone and Crow Formation (South Nicholson Group).|16-MAY-23
68733|Connellys Volcanics|Age reasons|Constrained only by the underlying Murphy Metamorphics (minimum age 1870 Ma; age of Barramundi Orogeny; Page and Williams 1988) and overlying South Nicholson Group (maximum age ~1500 Ma; by correlation with Roper Group; Jackson et al 1999, Abbott et al 2001). Most likely to be 1845-1860 Ma based on correlation with the Cliffdale Volcanics (dated by Page et al 2000).|16-MAY-23
68733|Connellys Volcanics|Correlations|Probably the Cliffdale Volcanics in CALVERT HILLS (Ahmad and Wygralak 1989).|16-MAY-23
68733|Connellys Volcanics|Defn author|Rawlings, D.J. [approved 11-APR-2005]|16-MAY-23
68733|Connellys Volcanics|Comments|Note: All locations are based on the GDA94 geodetic datum. Standard series 1:250 000 sheet names are shown in upper case.|16-MAY-23
68733|Connellys Volcanics|References|ABBOTT S.T., Sweet I.P., Plumb K.A., Young D.N., Cutovinos A., Ferenczi P.A., Brakel A. and Pietsch B.A., 2001. Roper region: Urapunga and Roper River special, Northern Territory (Second Edition); 1:250 000 Geological Map Series, sheets SD53-10,11. Northern Territory Geological Survey-Australian Geological Survey Organisation (NGMA), Map and Explanatory Notes.   **AHMAD M. and Wygralak A.S., 1989. Calvert Hills, Northern Territory (First Edition); 1:250 000 Metallogenic Map Series, sheet SE53-8. Northern Territory Geological Survey, Map and Explanatory Notes.**JACKSON M.J., Sweet I.P., Page R.W. and Bradshaw B.E., 1999. The South Nicholson and Roper Groups: evidence for the early Proterozoic Roper Superbasin. In: Bradshaw B.E. and Scott D.L. (Eds.), Integrated basin analysis of the Isa Superbasin using seismic, well-log and geopotential data: an evaluation of the economic potential of the northern Lawn Hill Platform. Australian Geological Survey Organisation, Record 1999/19 (unpaginated).   **PAGE R.W., Jackson M.J. and Krassay A.A., 2000. Constraining sequence stratigraphy in north Australian basins: SHRIMP U-Pb zircon geochronology between Mt Isa and McArthur River. Australian Journal of Earth Sciences, 47, 3; 431-459.  **PAGE R.W. and Williams I.S., 1988. Age of the Barramundi Orogeny in northern Australia by means of ion microprobe and conventional U-Pb zircon studies. In: Wyborn L.A.I. and Etheridge M.A. (Eds.), The early to middle Proterozoic of Australia. Precambrian Research, 40-41; 21-36.  **RAWLINGS D.J. Sweet I.P. and Kruse P.D., in prep [2008]. Mount Drummond, Northern Territory (Second Edition); 1:250 000 Geological Map Series, sheet SE53-12. Northern Territory Geological Survey, Map and Explanatory Notes.  **ROBERTS H.G., Rhodes J.M. and Yates K.R., 1963. Calvert Hills, N.T. (First Edition); 1:250,000 geological series, sheet SE53-8. Bureau of Mineral Resources, Geology and Geophysics, Map and Explanatory Notes.  **SMITH J.W. and Roberts H.G., 1963. Mount Drummond, N.T. (First Edition); 1:250,000 geological series, sheet SE53-12. Bureau of Mineral Resources, Geology and Geophysics, Map and Explanatory Notes.|16-MAY-23
78894|Conner Member|Name source|After Mount Conner (MGA94, 52J, 791349mN, 7177358mE), where this unit is exposed in the outer ridge of Mount Conner. Mount Conner is on the eastern most portion of AYERS ROCK 250k mapsheet.|16-MAY-23
78894|Conner Member|Unit history|The rocks surrounding Mount Conner, now recognised as the Conner Member were previously mapped as Inindia beds by Young et al 2002b. The Inindia beds are equivalent with the Areyonga to Julie formation succession recognised in the northeast of the Amadeus Basin.|16-MAY-23
78894|Conner Member|Geomorphic expression|Mostly continuous ridge of sandstone, with large cross beds. These cross beds weather to form a platy exposure. Mount Conner is a mesa approximately 300 m above the surrounding landscape, ridges comprised of several near-vertical cliffs surround the mesa. The Conner Member forms the outermost ridge of Mount Conner.|16-MAY-23
78894|Conner Member|Type section locality|Outer ridge on western side of Mount Conner (MGA94, 52J, 782684mN, 7176885mE), the ridge extends around most of Mount Conner.  The most complete exposure of the Conner Member crops out on the western to northwestern side.|16-MAY-23
78894|Conner Member|Extent|Outer ridge of Mount Conner, AYERS ROCK 250k mapsheet.|16-MAY-23
78894|Conner Member|General description|Red to orange sandstone resistant to weathering, often forming ridges.|16-MAY-23
78894|Conner Member|Thickness range|At least 400 m as seen in outcrop, however as the upper and lower boundaries are obscured the true thickness of the unit are unknown.|16-MAY-23
78894|Conner Member|Lithology|The unit is comprised of a medium grained, well-rounded and sorted, clean quartz sandstone overlying a lower sandstone that is massively bedded and well laminated. The sandstone has large angle cross beds with foresets of ~ 30°. These sedimentary structures weather to form flaggy surfaces.|16-MAY-23
78894|Conner Member|Depositional environment|Rounding and sorting of the sandstone as well as the nature of the cross beds indicate an aeolian depositional environment. It is possible that the deposition of the Conner Member was associated with the Sturtian glaciation when climatic conditions were dry and very cold (Rodríguez-López et al 2014).|16-MAY-23
78894|Conner Member|Relationships and boundaries|The Conner Member sits stratagraphically between exposures of diamictite of the Areyonga Formation and stromatolitic dolostone units of the Aralka Formation. The upper and lower contacts of the Conner Member are not exposed, as there is Cenozoic aeolian sands between the exposures of Conner Member and underlying the Areyonga Formation diamicities (which are small, discrete outcrops) and the overlying Areyonga Formation which is partially obscured. Due to the poor exposures (mostly obscured by Cenozoic aeolian sands) of the Areyonga Formation overlying the Conner Member exposures, it is difficult to determine the relationship of the Conner Member with its parent unit, the Areyonga Formation, however it is assumed that the member sits within the Areyonga Formation and does not cap the unit.|16-MAY-23
78894|Conner Member|Identifying features|Well rounded, well sorted sandstone which has large angle cross bedding and in foresets of 30°.|16-MAY-23
78894|Conner Member|Age reasons|Assumed Sturtian in age due to the stratigraphic position in the upper part of the Areyonga Formation. The Areyonga Formation are glacial sediments deposited during the Sturtian glaciation (Preiss et al 1978). The Sturtian glaciation is now considered to have lasted from about 720 to 660 Ma [this is within the Cryogenian period].|16-MAY-23
78894|Conner Member|Geophysical Expression|Some expression of the ridge in the 1VD magnetics and minor expression in ternary radiometrics.|16-MAY-23
78894|Conner Member|Defn author|VJ Normington, CJ Edgoose 10-DEC-2014.|16-MAY-23
78894|Conner Member|References|Preiss W, Walter M, Coats R and Wells A, 1978. Lithological correlations of Adelaidean glaciogenic rocks in parts of the Amadeus, Ngalia, and Georgina basins. BMR Journal of Australian Geology and Geophysics 3, 43-53. **Rodríguez-López JP, Clemmensen LB, Lancaster N, Mountney NP and Veiga GD, 2014. Archean to Recent aeolian sand systems and their sedimentary record: Current understanding and future prospects. Sedimentology.|16-MAY-23
26495|Copia Granite|Name source|After Copia Bore (GR 4615E, 74985N, AMG, metric) just southwest of outcrop area. Copia Bore is located adjacent to the Sandover stockroute in the central-eastern part of the Alcoota 1:250 000 Sheet area, SF53-10, Australian Map Grid.|16-MAY-23
26495|Copia Granite|Type section locality|In low cirque-like scarp about 7 km northeast of Copia Bore at GR 4660E, 75040N AMG - metric.|16-MAY-23
26495|Copia Granite|Description at type locality|Type exposure: Well foliated gneiss with distinct mafic and felsic layers. Medium grained.|16-MAY-23
26495|Copia Granite|Extent|From 5 km northeast of Copia Bore northwards as far as 10 km southwest of Western Watering Point, 'Delmore Downs' Station (GR. 4760E, 5191N).|16-MAY-23
26495|Copia Granite|Lithology|Coarse-grained gneissic biotite granite.|16-MAY-23
26495|Copia Granite|Relationships and boundaries|Gradational contact with Delny Gneiss over distances up to several metres. Boundary cross-cuts trends in Delny Gneiss on a broad scale. Intruded by Ida Granite.|16-MAY-23
26495|Copia Granite|Proposed publication|BMR Report|16-MAY-23
26495|Copia Granite|Comments|Strongly developed foliation. Intruded by maafic dykes that appear to be thermally metamorphosed.|16-MAY-23
4739|Coronation Sandstone|Name source|Coronation Hill, latitude 13o36'S, longitude 132o36'E, Stow 1:100 000 Sheet area.|16-MAY-23
4739|Coronation Sandstone|Unit history|Includes all outcrops previously referred to as the Coronation Member of the Edith River Volcanics, also some areas mapped as undifferentiated Edith River Volcanics (Walpole & others, 1968).|16-MAY-23
4739|Coronation Sandstone|Type section locality|3 km east-southeast from El Sherana, GR 341039 (bottom) to GR 332047 (top) STOW 1:100 000 Sheet area.|16-MAY-23
4739|Coronation Sandstone|Extent|Discontinuous outcrop in the South Alligator Valley between 10 km southeast of Big Sunday (STOW) and Rockhole Mine (MUNDOGIE 1:100 000 Sheet area). Minor scattered outcrop throughout northeastern STOW.|16-MAY-23
4739|Coronation Sandstone|Thickness range|Ranges up to 750 metres.|16-MAY-23
4739|Coronation Sandstone|Lithology|Valley-fill sequence of mixed sediments and volcanics, including coarse to pebbly quartz sandstone, polymictic pebble to boulder conglomerate, brown and purple shale, siltstone, sandy siltstone, micaceous greywacke, lithic tuff, ignimbrite, rhyolite, amygdaloidal basalt, andesite and dacite. Sandstone forms lenses up to 25 m thick; conglomerates are mostly associated with basal sandstone beds.|16-MAY-23
4739|Coronation Sandstone|Relationships and boundaries|Basal unit of the El Sherana Group. Unconformably overlies metamorphosed sediments of the Pine Creek Geosyncline (1800 m.y.). Conformably overlain by the Pul Pul Rhyolite. Unconformably overlain by the Kombolgie Formation (1650 m.y.)|16-MAY-23
4739|Coronation Sandstone|Age reasons|Late Early Proterozoic (1800-1730 m.y.) see above.  1730 m.y. youngest age as indicated by the 1780-1730 m.y. age of the Cullen Granite Complex which intrudes younger units of the El Sherana Group.|16-MAY-23
24230|Coulters Sandstone|Name source|Coulters Waterhole on the Frew River at GR 028781, Hatches 1:100 000 Sheet area, Frew River 1:250 000 Sheet area.|16-MAY-23
24230|Coulters Sandstone|Type section locality|2 km north of Coulters Waterhole (latitude 20o59'55"S, longitude 135o01'50"E) in southwestern Hatches 1:100 000 Sheet area; the base is at GR 027 800 and the section runs eastwards to the top at GR 034801. The formation here is 500 m thick, and consists predominantly of fine to medium-grained, cross-bedded quartz arenite; however, it is pebbly near base, contains a central band, 25 m thick of very fine-grained lithic arenite, and is medium to coarse-grained at top.|16-MAY-23
24230|Coulters Sandstone|Extent|Throughout the Davenport Province - eastern and central parts of Bonney Well, southwestern part of Frew River, northwestern part of Elkedra, and northeastern part of Barrow Creek 1:250 0000 Sheet areas.|16-MAY-23
24230|Coulters Sandstone|Thickness range|Ranges from about 300 m to at least 1000 m and possibly up to 3000 m (e.g., in the southeast of Hatches 1:100 000 Sheet area); is 500 m in type section.|16-MAY-23
24230|Coulters Sandstone|Lithology|Ridge-forming quartz arenite and slightly feldspathic or lithic quartz arenite; minor pebbly arenite and recessive friable kaolinitic or sericitic arenite, siltstone and altered basaltic? lava. Two recessive bands, up to about 100 m thick, present in the southeast, one near the centre of the formation, the other near the top. Arenites are mostly white, pale pink, or pale grey, well sorted, medium to coarse grained, medium to thick-bedded, and cross-bedded; ripple marks are common, particularly towards the top of the formation.|16-MAY-23
24230|Coulters Sandstone|Relationships and boundaries|Conformable on Arabulja Volcanics, conformable and probably disconformable on Newlands Volcanics, conformable and locally unconformable on Yeeradgi Sandstone; overlain conformably by Frew River Formation and, in northwest, by Kudinga Basalt. Lower and upper contacts taken at abrupt topographic break between ridge-forming Coulters Sandstone and recessive underlying and overlying formations.|16-MAY-23
24230|Coulters Sandstone|Age reasons|Younger than 1870 m.y. - U-Pb zircon age of volcanics in the Warramunga Group, which is overlain unconformably by the Hatches Creek Group. Older than 1640 m.y. - Rb-Sr whole-rock approximate age of granite intruding the Hatches Creek Group.|16-MAY-23
24230|Coulters Sandstone|Comments|Prominent ridge-forming unit. Part of the Wauchope Subgroup of the Hatches Creek Group.|16-MAY-23
24636|Cox Formation|Name source|Cox River, Mount Young 1:250 000 scale map sheet area.|16-MAY-23
24636|Cox Formation|Geomorphic expression|Low rubbly rises and small hills on top of plateau.|16-MAY-23
24636|Cox Formation|Type section locality|The area surrounding latitude 15o55'S, longitude 135o01'E. Basal contact exposed at latitude 15o56'00"S, longitude 135o02'00"E (AMG grid reference NC035385). Top contact with Cretaceous rocks at latitude 15o55'00"S, longitude 135o00'40"E (NC013402). No section can be specified due to the incomplete nature of outcrop.|16-MAY-23
24636|Cox Formation|Extent|Restricted to the top of a plateau in the southwest corner of the Mount Young and southeastern corner of the Hodgson Downs 1:250 000 map sheet areas. |16-MAY-23
24636|Cox Formation|Thickness range|The maximum preserved thickness is estimated to be about 50 m.|16-MAY-23
24636|Cox Formation|Lithology|Lower part: fine- to very fine-grained micaceous sandstone thinly interbedded with micaceous siltstone. Upper part: red and green finely laminated siltstone and shale predominate over minor fine-grained sandstone interbeds.|16-MAY-23
24636|Cox Formation|Depositional environment|Shallow marine subtidal setting.|16-MAY-23
24636|Cox Formation|Relationships and boundaries|Conformably overlies the Bukalara Sandstone. Basal contact picked where massive and cross-bedded sandstones of the Bukalara Sandstone give way to thinly bedded, fine-grained sandstones of the Cox Formation. Unconformably overlain by Cretaceous and Cainozoic deposits. Not assigned to any group.|16-MAY-23
24636|Cox Formation|Age reasons|No fossil evidence. Probably Early Cambrian based on the interpreted Early Cambrian age of the underlying Bukalara Sandstone (Pietsch and others, 1991).|16-MAY-23
24636|Cox Formation|Correlations|The Nutwood Downs Volcanics occupies the same stratigraphic position, i.e. conformably overlies the Bukalara Sandstone, in the western part of the Hodgson Downs 1:250 000 scale map sheet area (Dunn, 1963). The Raiwalla Shale (Arafura Basin) is also a probable correlative.|16-MAY-23
84107|Creswell Creek Formation|Name source|Unit name derived from Creswell Creek, which runs across parts of the BRUNETTE DOWNS, MOUNT DRUMMOND, and CALVERT HILLS 1:250 000 mapsheets in the Northern Territory. Creswell Creek rises at approximately (GDA94) 17°40’13”S 136°41’50”E on the CALVERT HILLS mapsheet.|
84107|Creswell Creek Formation|Unit history|Unit originally mapped as the “Mittiebah Sandstone” in the First Edition MOUNT DRUMMOND 1:250 000 mapsheet by Smith and Roberts (1963a, b). This nomenclature was retained in the Second Edition map of MOUNT DRUMMOND by Rawlings et al (2006, 2008). The “Mittiebah Sandstone” in the northwestern area of MOUNT DRUMMOND (Canyon Range) is redefined as the “Creswell Creek Formation” by Simmons et al (2023a, b).|
84107|Creswell Creek Formation|Geomorphic expression|The Creswell Creek Formation mainly outcrops as either a series of small, dome-shaped inliers, or resistant, banded ridges (Rawlings et al, 2008).|
84107|Creswell Creek Formation|Type section locality|No type locality defined. A reference area is nominated in the northwestern MOUNT DRUMMOND 1:250 000 mapsheet, in the vicinity of (GDA94) 18°16’S 136°36’E (53K 669142mE 7979571mN).|04-OCT-23
84107|Creswell Creek Formation|Extent|The Creswell Creek Formation mostly outcrops across the northwestern MOUNT DRUMMOND and northeastern BRUNETTE DOWNS 1:250 000 mapsheets, with isolated outcrops across the southern CALVERT HILLS and southeastern WALHALLOW 1:250 000 mapsheets.|
84107|Creswell Creek Formation|Thickness range|In the reference area in the north-western MOUNT DRUMMOND 1:250 000 mapsheet (Canyon Range), the Creswell Creek Formation varies in thickness from approximately 450 m to 1700 m thick (Rawlings et al, 2008).|
84107|Creswell Creek Formation|Lithology|The Creswell Creek Formation is mainly composed of pale yellow to pink, fine- to medium-grained (± coarse-grained), quartzose to lithic sandstone, with locally developed conglomerates, mainly comprised of chert, quartzite and quartz clasts. The sandstone is largely planar-bedded with large-scale planar and trough cross-beds. There is also one thin (<50 m-thick) recessive interval of red/brown siltstone (Rawlings et al, 2008).|
84107|Creswell Creek Formation|Depositional environment|Depositional setting likely alternated between storm-influenced shallow-marine and braided-fluvial environments (Rawlings et al, 2008).|
84107|Creswell Creek Formation|Relationships and boundaries|The Creswell Creek Formation conformably overlies the Mingabarri Formation (and the Boxer Member of the Mingabarri Formation where present), and is unconformably overlain by units of the South Nicholson Group.|
84107|Creswell Creek Formation|Identifying features|The Creswell Creek Formation contains scattered pebbles and cobbles of chert, quartzite and quartz up to 15 cm in diameter, especially in the basal 20 m of the unit (Rawlings et al, 2008).|
84107|Creswell Creek Formation|Age reasons|Maximum depositional age derived from U-Pb SHRIMP dating of detrital zircons: Wangalinji Member of the Playford Sandstone (stratigraphically overlies the Creswell Creek Sandstone): GA Sample 2785614 – 1600 ± 20 Ma (Kositcin and Carson, 2019). Creswell Creek Formation: GA sample 2676117 – 1658 ± 23 Ma (Anderson et al, 2019). Creswell Creek Formation: GA Sample 3305198 - 1625 ± 27 Ma (Kositcin et al, 2020). Therefore, the potential depositional age range for the Creswell Creek Sandstone can be considered to extend from ca. 1658 ± 23 Ma to 1625 ± 27 Ma.|
84107|Creswell Creek Formation|Correlations|The Creswell Creek Formation, based on similar maximum depositional age estimates with other units, can be correlated with the ungrouped Caulfield Formation and several formations of the McNamara Group, including the Shady Bore Quartzite, the Bullrush Conglomerate and the Plain Creek Formation (Kositcin and Carson, 2019). The Creswell Creek Formation may be correlative with components of the upper Glyde package to the lowermost Favenc package of the McArthur Basin (Rawlings, 1999).|
84107|Creswell Creek Formation|Geophysical Expression|Weak to moderate magnetic response.|
84107|Creswell Creek Formation|Geochemistry|One outcrop sample of the Creswell Creek Formation (formerly Mittebah Sandstone) (GA Sample No: 2678589) was analysed for major, minor and trace element geochemistry using X-ray fluorescence (XRF) and quadrupole inductively coupled plasma mass spectrometry (ICP-MS). (Carson et al, 2020).|
84107|Creswell Creek Formation|Defn author|Elliot Foley, Jack Simmons, Ben Williams, Charles Verdel (Northern Territory Geological Survey), Chris Carson (Geoscience Australia) 31-May-2023.|
84107|Creswell Creek Formation|Comments|Note: Standard series 1: 100 000 and 1: 250 000 mapsheet names are shown in uppercase.|
84107|Creswell Creek Formation|References|Anderson JR, Lewis CJ, Jarrett AJM, Carr LK, Henson P, Carson CJ, Southby C and Munson TJ, 2019. New SHRIMP U–Pb zircon ages from the South Nicholson Basin, Mount Isa Province and Georgina Basin, Northern Territory and Queensland. Geoscience Australia, Record 2019/10. 
 **Carson CJ, Jarrett AJM, Anderson JR, Champion DC and Henson PA, 2020. Exploring for the Future – Whole rock geochemistry data release of sedimentary and igneous rocks from the South Nicholson region, Northern Territory and Queensland. Geoscience Australia, Record 2020/02.  **Carson, C. J., Kositcin, N., Anderson, J. R., and Henson, P. A. in prep. A revised Proterozoic tectono-stratigraphy of the South Nicholson region, Northern Territory, Australia - insights from SHRIMP U-Pb detrital zircon geochronology. Australian Journal of Earth Sciences.  **Kositcin N and Carson CJ, 2019. New SHRIMP U-Pb zircon ages from the South Nicholson and Carrara Range regions, Northern Territory. Geoscience Australia, Record 2019/09.  **Kositcin N, Carson CJ, Anderson JR, Doublier MP and Murr J, 2020. Exploring for the Future - New SHRIMP geochronology constraints on the basin evolution of the South Nicholson region. Geoscience Australia, Record 2020/025.  **Rawlings DJ, 1999. Stratigraphic resolution of a multiphase intracratonic basin system: the McArthur Basin, northern Australia. Australian Journal of Earth Sciences 46(5), 703–723.  **Rawlings DJ, Sweet IP and Kruse PD, 2006. Mount Drummond, NT (Second Edition). 1:250 000 Geological Map, Sheet SE 53-12. Northern Territory Geological Survey, Darwin, Northern Territory.  **Rawlings DJ, Sweet IP and Kruse PD, 2008. Mount Drummond, NT (Second Edition). 1:250 000 Geological Map Series Explanatory Notes, Sheet SE 53-12. Northern Territory Geological Survey, Darwin, Northern Territory.  **Simmons JM, Williams B, Carson, C and Verdel C, 2023a. Mount Drummond, Northern Territory 1:250 000 Geological Map, Sheet SE 53-12 (Third Edition). Northern Territory Geological Survey, Darwin, Northern Territory.  **Simmons JM, Williams B, Carson, C and Verdel C, 2023b. Mount Drummond, Northern Territory 1:250 000 Geological Map Explanatory Notes, Sheet SE 53-12 (Third Edition). Northern Territory Geological Survey, Darwin, Northern Territory.  **Smith JW and Roberts HG, 1963a. Mount Drummond, NT (First Edition). 1:250 000 Geological Map Series Explanatory Notes, Sheet 53-12. Bureau of Mineral Resources, Canberra.  **Smith JW and Roberts HG, 1963b. Mount Drummond, NT (First Edition). 1:250 000 Geological Map Series, Sheet SE 53-12. Bureau of Mineral Resources, Canberra.|
26504|Crooked Hole Granite|Name source|After Crooked Hole Creek which has its headwaters in outcrop area, central Alcoota Sheet area, SF53-10, Australian map Grid.|16-MAY-23
26504|Crooked Hole Granite|Unit history|Previous informal name: Crooked Hole Creek Granite.|16-MAY-23
26504|Crooked Hole Granite|Type section locality|In low hills centred on GR 4350E, 7515N (AMG metric) and up to 2 km to east and west; area four km NNW of Arno Peak.|16-MAY-23
26504|Crooked Hole Granite|Description at type locality|Foliated gneiss with biotitic layers intruding Delny Gneiss.|16-MAY-23
26504|Crooked Hole Granite|Extent|In the headwaters of Crooked Hole Creek between Boomerang Bore (GR. 430E, 75145N, AMG) and Muller Bore (GR 448E, 7580N, AMG metric).|16-MAY-23
26504|Crooked Hole Granite|Lithology|Gneissic biotite granite, small amount of hornblende-bearing granite.|16-MAY-23
26504|Crooked Hole Granite|Relationships and boundaries|Intrudes Delmore Metamorphics and probably the Mapata Gneiss with sharp margins. Intruded by Woodgreen Granite Complex. Similar to Copia Granite. Intrudes Delny Gneiss.|16-MAY-23
26504|Crooked Hole Granite|Proposed publication|BMR Report|16-MAY-23
26504|Crooked Hole Granite|Comments|Strongly gneissic, pegmatites are developed in the country rock marginally around the granite.|16-MAY-23
37729|Crow Formation|Name source|Crow Creek, in western MOUNT DRUMMOND, near latitude 18o27'S longitude 136o50'E.|16-MAY-23
37729|Crow Formation|Unit history|Encompasses about half of the outcrop that was formerly mapped as Mullera Formation by Smith and Roberts (1963) in the western half of the first edition of MOUNT DRUMMOND. It also incorporates a narrow strip of moderately resistant outcrop at the southern edge of the Mittiebah Range that was formerly mapped by Smith and Roberts (1963) as Mittiebah Sandstone. This Mittiebah Range outcrop, plus a similar narrow strip of Crow Formation along the Canyon Range, are reassigned to a separate upper member of the Crow Formation - the Tobacco Member. Crow Formation also includes a small anticlinal outcrop area in the Canyon Range (710000E 7995000N) that was incorrectly mapped as 'Benmara beds' by Smith and Roberts (1963).|16-MAY-23
37729|Crow Formation|Constituents|Tobacco Member (separate definition and type area).|16-MAY-23
37729|Crow Formation|Geomorphic expression|Recessive with variably white to dark phototones.|16-MAY-23
37729|Crow Formation|Type section locality|North-striking valley of moderately resistant outcrop at latitude 18o5'S longitude 136o55'E in the headwaters of Murphy's Creek in the Canyon Range in MOUNT DRUMMOND. The section runs from 705200E 8000000N (lower boundary) to 702000E 8000600N (upper boundary). In this area, Crow Formation conformably overlies Bowgan Sandstone and is in turn conformably overlain by Mittiebah Sandstone. Tobacco Member has not been differentiated out of the Crow Formation at this locality, so the type section includes a correlative section of Tobacco Member. This is designated as a reference section for the Tobacco Member.|16-MAY-23
37729|Crow Formation|Extent|Widespread in the western half of MOUNT DRUMMOND, and a small part of the adjoining southwestern CALVERT HILLS.|16-MAY-23
37729|Crow Formation|Thickness range|Up to 2500 m. This is a gross estimate, because outcrop is poor and measurable dips are rare. There are also structural complications.|16-MAY-23
37729|Crow Formation|Lithology|Interbedded siltstone, sandstone, shale and lesser conglomerate, which can be divided into several facies. Shelf facies is present throughout the outcrop belt and comprises shaly to flaggy white clayey micaceous siltstone and fine- to medium-grained quartzose to sublithic (+/-micaceous) sandstone, red/brown to grey shale and leached chalky white or maroon mottled porcellanous claystone. Shale is interpreted to have a carbonaceous and/or pyritic component, based on the presence of mottled ferruginous and saprolitic weathering products, but this has not been demonstrated in outcrop or drilling. Bedding ranges from massive to parallel-laminated to 'tempestite' textured, including wavy and lenticular bedding, hummocky cross-stratification, flute molds, tool marks and current lineation.   Debris flow and sandstone turbidite facies is recognised almost only in the Canyon Range area and is composed of mottled white to brown, poorly-sorted, feldspathic, micaceous, ferruginous and lithic, medium- to very coarse-grained sandstone, pebbly sandstone and lesser matrix-supported polymict conglomerate. These constitute decimetre-scale beds that are massive or crudely parallel- or cross-laminated, graded or upward-graded with typical turbidite features. Shallow water sandstone facies occurs as discrete localised units within the Crow Formation, one of which is mapped informally (Psos). It entails a number of different but overlapping facies, most commonly white to maroon, fine- to very coarse-grained quartzose to lithic sandstone with locally abundant rounded pebbles and localised poorly-sorted pebble-cobble polymict conglomerate. Sandstone is locally ferruginous, micaceous and glauconitic. Bedding is medium to very thick with planar and trough cross-beds of various dimensions, planar bedding, current lineation, mudclasts, synaeresis cracks and hummocky cross-stratification.|09-OCT-23
37729|Crow Formation|Relationships and boundaries|Lies conformably on Bowgan Sandstone in the Canyon Range area, on the northwest side of the Benmara Fault. The base of the formation is poorly exposed and is locally covered by saprolite. Locally, Bowgan Sandstone is absent and Crow Formation sits directly on Benmara Group and Murphy Metamorphics (eg around 705000E 8008000N). South and east of Benmara Fault, the Crow Formation conformably overlies Playford Sandstone. In the Canyon and Mittiebah Ranges, the Crow Formation is conformably or disconformably overlain by Mittiebah Sandstone. Elsewhere, it is disconformably or unconformably overlain by Constance Sandstone. The Crow Formation pinches out immediately west of Mitchiebo Waterhole and along strike to the east near No Mans Creek (755000E 7944000N), due to erosion, depositional onlap and/or faulting. Parent Unit: Crow Formation is part of the Wild Cow Subgroup, South Nicholson Group.|16-MAY-23
37729|Crow Formation|Age reasons|Radiometric dating is currently unavailable for any part of the South Nicholson Group and its age is therefore internally unconstrained. The maximum age of 1595+/-6 Ma is that of the Lawn Hill Formation at the top of the underlying McNamara Group (Page and Sweet 1998). There are no minimum age constraints imposed by overlying units, apart from the late Neoproterozoic to Phanerozoic Georgina Basin. The interpreted age range of the Crow Formation of 1500 to 1400 Ma is based on correlation with the Roper Group of the southern McArthur Basin, which combined, make up the Roper superbasin (Jackson et al 1999, Abbott et al 2001).|16-MAY-23
37729|Crow Formation|Correlations|Tentatively, equivalent to part of the Mainoru Formation, Roper Group.|16-MAY-23
37729|Crow Formation|Defn author|Rawlings, D.J. [approved 11-APR-2005]|16-MAY-23
37729|Crow Formation|Comments|Reference areas: Area 1: recessive outcrop at latitude 18o39'S longitude 137o6'E (721500E 7937800N) along a small creek that feeds into Mitchiebo Waterhole in MOUNT DRUMMOND. This is adjacent to the Mittiebah-Wangalinji road and reasonably easy to access. However, it only covers a small portion of the sequence and is not fully representative of the formation. It conformably overlies Playford Sandstone and is in turn unconformably overlain by Constance Sandstone. Area 2: narrow strike ridge at latitude 18o30'S longitude 137o7'E (724000E 7952100N) 15 km north of Mitchiebo Waterhole in MOUNT DRUMMOND, containing the unnamed sandstone unit Psos. Note: All locations are based on the GDA94 geodetic datum. Standard series 1:250 000 sheet names are shown in upper case.|16-MAY-23
37729|Crow Formation|References|**ABBOTT S.T., Sweet I.P., Plumb K.A., Young D.N., Cutovinos A., Ferenczi P.A., Brakel A. and Pietsch B.A., 2001. Roper region: Urapunga and Roper River special, Northern Territory (Second Edition); 1:250 000 Geological Map Series, sheets SD53-10,11. Northern Territory Geological Survey-Australian Geological Survey Organisation (NGMA), Map and Explanatory Notes.  **JACKSON M.J., Sweet I.P., Page R.W. and Bradshaw B.E., 1999. The South Nicholson and Roper Groups: evidence for the early Proterozoic Roper Superbasin. In: Bradshaw B.E. and Scott D.L. (Eds.), Integrated basin analysis of the Isa Superbasin using seismic, well-log and geopotential data: an evaluation of the economic potential of the northern Lawn Hill Platform. Australian Geological Survey Organisation, Record 1999/19 (unpaginated).   **PAGE R.W. and Sweet I.P., 1998. Geochronology of basin phases in the western Mount Isa Inlier, and correlation with the McArthur Basin. Australian Journal of Earth Sciences, 45, 2; 219-232.    **SMITH J.W. and Roberts H.G., 1963. Mount Drummond, N.T. (First Edition); 1:250,000 geological series, sheet SE53-12. Bureau of Mineral Resources, Geology and Geophysics, Map and Explanatory Notes.|16-MAY-23
76183|Culaly Amphibolite|Name source|After Culaly Plain in East Alligator 1:100 000 mapsheet 5373 (Record ID - NT 12087) GDA 94 53L, 223877mE 8638815mN (12o18'5"S 132o27'41"E) on Alligator River 1:250 000 mapsheet, East Alligator 1:100 000 mapsheet, Nimbuwah Domain, Pine Creek Orogen, Northern Territory.|16-MAY-23
76183|Culaly Amphibolite|Unit history|Previously mapped as Zamu Complex (in part; Stewart 1959 unpublished, as cited in Ferguson and Needham 1978, modified Bryan 1962 and Walpole 1962); or Zamu Dolerite (in part; Ferguson and Needham 1978).|16-MAY-23
76183|Culaly Amphibolite|Geomorphic expression|Massive blocky exposures in drainage system, locally forming platforms.|16-MAY-23
76183|Culaly Amphibolite|Type section locality|Isolated exposure in Tin Camp Creek, in Myra Falls Inlier, Alligator River 1:250 000, Oenpelli 1:100 000 mapsheets. GDA94 53L 318292mE 8622008mN (-12o27'36"S 133o19'41"E).|16-MAY-23
76183|Culaly Amphibolite|Description at type locality|Forms large blocky river-washed platform exposures within Neoarchaean Kukalak Gneiss. Foliation trends east-west at this location.|16-MAY-23
76183|Culaly Amphibolite|Extent|Isolated river-washed blocky platform exposures restricted to southeast Myra Falls Inlier, Nimbuwah Domain, Pine Creek Orogen.|16-MAY-23
76183|Culaly Amphibolite|General description|Mafic amphibolite, locally garnet bearing, surrounded by Neoarchaean Kukalak Gneiss and adjacent to Palaeoproterozoic Kudjumarndi Quartzite.|16-MAY-23
76183|Culaly Amphibolite|Lithology|Mafic amphibolite, with foliation defined by ~1-3 mm anhedral plagioclase feldspar in amphibole (green-brown hornblende) matrix. Feldspars are often sericitised and associated with interstitial quartz. Locally garnet-bearing. Garnet has asymmetric tails (top direction to west) and is commonly poikilitic with encircling coronas composed of recrystallised feldspar.|16-MAY-23
76183|Culaly Amphibolite|Depositional environment|Intrusive, but contacts are obscured.|16-MAY-23
76183|Culaly Amphibolite|Relationships and boundaries|Contact relationships not observed, but occurs within Neoarchaean Kukalak Gneiss and is adjacent to Kudjumarndi Quartzite of the Kakadu Group, Pine Creek Orogen.|16-MAY-23
76183|Culaly Amphibolite|Identifying features|Dominantly high-Ti tholeiitic geochemical composition; garnet (where present) has asymmetric tails and corona rims of recrystallised feldspar.|16-MAY-23
76183|Culaly Amphibolite|Structure and Metamorphism|Amphibolite-facies metamorphism, east-west foliation defined by plagioclase feldspar. Garnet porphyroblasts (where present) have asymmetric tails (top direction to west) and are commonly poikilitic with encircling coronas composed of recrystallised feldspar.|16-MAY-23
76183|Culaly Amphibolite|Age reasons|Not adequately constrained; possibly Archaean as it occurs within Neoarchaean Kukalak Gneiss.|16-MAY-23
76183|Culaly Amphibolite|Alteration and Mineralisation|Some sericitisation of plagioclase feldspar.|16-MAY-23
76183|Culaly Amphibolite|Geophysical Expression|Too small to be depicted in geophysical imagery.|16-MAY-23
76183|Culaly Amphibolite|Geochemistry|Dominantly high-Ti primary compositions, hypersthene-normative tholeiite.|16-MAY-23
76183|Culaly Amphibolite|Defn author|LM Glass, JA Hollis, 2012|16-MAY-23
76183|Culaly Amphibolite|Proposed publication|Hollis JA and Glass LM, 2012. Howship and Oenpelli, Northern Territory. 1:100 00 geological map series explanatory notes, 5572, 5573. Northern Territory Geological Survey, Darwin.|16-MAY-23
76183|Culaly Amphibolite|References|Bryan R, 1962. Lower Proterozoic basic intrusive rocks of the Katherine-Darwin area, Northern Territory. Bureau of Mineral Resources, Australia, Record 1962/07.***Walpole BP, 1962. Mount Evelyn, Northern Territory, 1:250 000 Geological Series Explanatory Notes, SD53/5. Bureau of Mineral Resources, Australia, Canberra.***Ferguson J and Needham RS, 1978. The Zamu Dolerite: A lower Proterozoic pre-orogenic continental tholeiitic suite from the Northern Territory, Australia. Journal of the Geological Society of Australia 25(6), 309-322.|16-MAY-23
29771|Cumming Leucogabbro|Name source|Cumming Yard 133o04'E 23o42'S.|16-MAY-23
29771|Cumming Leucogabbro|Unit history|Previously unnamed mafic rocks (Marjoribanks, 1974; Offe, 1981).|16-MAY-23
29771|Cumming Leucogabbro|Geomorphic expression|Low dark rubbly rise.|16-MAY-23
29771|Cumming Leucogabbro|Type section locality|GR 301000 7379400 MacDonnell Ranges 1:100 000 Sheet area.|16-MAY-23
29771|Cumming Leucogabbro|Extent|Dismembered intrusion southeast of Fish Hole on Ellery Creek.|16-MAY-23
29771|Cumming Leucogabbro|Lithology|Tremolite- and actinolite-granofels, minor felsic veins.|16-MAY-23
29771|Cumming Leucogabbro|Relationships and boundaries|Cut by narrow mylonites of Alice Springs age and by wider Chewings High-strain Zones. Appears to intrude Chewings Range Quartzite.|16-MAY-23
29771|Cumming Leucogabbro|Structure and Metamorphism|It has undergone metamorphism at greenschist facies and is only weakly deformed.|16-MAY-23
29771|Cumming Leucogabbro|Age reasons|Mid Proterozoic: affected by latest regional metamorphism at about 1590 Ma, but later than Chewings Range Quartzite.|16-MAY-23
29771|Cumming Leucogabbro|Defn author|R.D. Shaw & G Wakelin-King, 1991.|16-MAY-23
29771|Cumming Leucogabbro|Comments|This 'definition' is missing the details of references mentioned in the synonymy, and shows no signs on the card of having been approved.|16-MAY-23
26509|Cyclops Member|Name source|The name is derived from Cyclops Bore (GDA 94 53K 432217mE 7389088mN)(Wells et al 1967), about 16 kilometres west of the Ross River Homestead; ALICE SPRINGS; UNDOOLYA, Amadeus Basin, Northern Territory.|16-MAY-23
26509|Cyclops Member|Unit history|The Cyclops Member was first defined by Wells et al (1967) as a part of the Pertatataka Formation and the unit has retained its position and name within the Pertatataka Formation after the redefinition of the Pertatataka Formation by Preiss et al (1978).|16-MAY-23
26509|Cyclops Member|Geomorphic expression|Exposures are typically ridges that can extend for several kilometres, although these ridges may be discontinuous.|16-MAY-23
26509|Cyclops Member|Type section locality|The proposed type area is located along the Ross Highway; isolated ridges of the unit run southwest to northeast in a similar orientation to the Heavitree Quartzite and Bitter Springs Group ridges. The best exposure within this area is approximately 1.3 m northwest of Cyclops Bore at GDA 94 53K 431692mE 7389785mN.|16-MAY-23
26509|Cyclops Member|Description at type locality|At the type area, fine to medium-grained, rhythmically bedded sandstone outcrops on the eastern side of the Ross Highway. This sandstone is flaggy, micaceous and contained occasional beds with ripple marks.|16-MAY-23
26509|Cyclops Member|Extent|The Cyclops Member is restricted to southeastern ALICE SPRINGS [1:250 000 sheet area].|16-MAY-23
26509|Cyclops Member|General description|The Cyclops Member is generally poorly exposed; exposures are typically discontinuous small ridges within flat-lying sand plains that likely cover Pertatataka Formation siltstone.|16-MAY-23
26509|Cyclops Member|Thickness range|Within the type area exposures are up to 3 m thick, however contacts with underlying and overlying strata is not observed. Wells et al (1967) define the Cyclops Member as about 50 m thick at Ross River but estimate that the member could be as thick as 75 m based on air-photograph interpretation.|16-MAY-23
26509|Cyclops Member|Lithology|The Cyclops Member is a platy sandstone with very thin beds and laminations; the beds are even and rhythmic. The sandstone is micaeous and fine-grained. This fine-grained, quartz sandstone is made up of up to 95 % interlocking quartz grains with mica flakes within a matrix with a composition which is likely a combination of micro quartz, clay minerals and Fe-oxide minerals.|16-MAY-23
26509|Cyclops Member|Depositional environment|The Cyclops Member was likely deposited during a eustatic rise triggered by the deglaciation of the Elatina ice sheet (Munson et al 2013), Walter et al (1995) suggested that the carbonate and siliciclastic rocks were deposited as a result of isostatic rebound. Wells et al (1967) postulated that the member was deposited in a shallow sea during a stable period with gentle subsidence and a regular supply of detrital material.|16-MAY-23
26509|Cyclops Member|Fossils|None known.|16-MAY-23
26509|Cyclops Member|Diastems or hiatuses|Nil.|16-MAY-23
26509|Cyclops Member|Relationships and boundaries|The contacts of the Cyclops Member are rarely exposed; it is likely that the recessive siltstone units of the Pertatataka Formation are both above and below the Cyclops Member.|16-MAY-23
26509|Cyclops Member|Identifying features|The unit is flaggy to fissile, thinly bedded and laminated micaeous sandstone. Bedding is rhythmic and even.|16-MAY-23
26509|Cyclops Member|Structure and Metamorphism|The member is typically horizontal or near-horizontal with little evidence for folding.|16-MAY-23
26509|Cyclops Member|Age reasons|The inferred depositional age of the Cyclops Member is ca 575 Ma (Maidment et al 2007). Recent detrital zircon grain analysis via U-Pb isotopic methods (SHRIMP) produced a maximum depositional age of 650 +/- 15 Ma (Kositcin et al 2015). This age is significantly younger than the maximum depositional age of ca 807 Ma determined by Maidment et al (2007) but is still considerably older than the inferred age of about 575 Ma of the Pertatataka Formation.|16-MAY-23
26509|Cyclops Member|Correlations|There are no known direct correlatives of the Cyclops Member due to the restricted distribution of the unit. The Pertatataka Formation is a correlative with the upper Inindia Beds in the central Amadeus Basin (Edgoose 2013).|16-MAY-23
26509|Cyclops Member|Alteration and Mineralisation|Petroleum: The Cyclops Member is included in the 3nd [rd?] Petroleum system of Marshall et al (2007); however, according to (Munson 2014), it is the siltstone of the Pertatataka Formation that is the potential source rock in this system, not the Cyclops Member.|16-MAY-23
26509|Cyclops Member|Geophysical Expression|Not known, unit is generally too small to be seen in regional geophysical imagery.|16-MAY-23
26509|Cyclops Member|Geochemistry|Not known.|16-MAY-23
26509|Cyclops Member|Defn author|VJ Normington, N Donnellan, 29-SEP-2015.|16-MAY-23
26509|Cyclops Member|References|Edgoose C, 2013. Amadeus Basin: in Ahmad M and Munson TJ (editors) 'Geology and mineral resources of the Northern Territory; Special Publication 5', Northern Territory Government.
Kositcin N, Normington V and Edgoose C, 2015. Summary of results. Joint NTGS¿GA geochronology project: Amadeus Basin, July 2013¿June 2014. NTGS Record 2015-001, Northern Territory Geological Survey.
Maidment DW, Williams IS and Hand M, 2007. Testing long-term patterns of basin sedimentation by detrital zircon geochronology, Centralian Superbasin, Australia. Basin Research 19, 355-360.
Marshall TR, Dyson IA and Liu Keyu, 2007. Petroleum systems in the Amadeus Basin, central Australia: Were they oil prone?: in Munson TJ and Ambrose GJ (editors) 'Proceedings of the Central Australian Basins Symposium, Alice Springs, 16 ¿ 18th August, 2005'. Alice Springs, Northern Territory Geological Survey, Special Publication 2, 136-146.
Munson TJ, 2014. Petroleum geology and potential of the onshore Northern Territory, 2014, Northern Territory Geological Survey, Report 22.
Munson TJ, Kruse PD and Ahmad M, 2013. Centralian Superbasin: in Ahmad M and Munson TJ (editors) 'Geology and mineral resources of the Northern Territory. NTGS Special Publication 5', Northern Territory Government.
Normington VJ and Donnellan N, in prep. Characterisation of the Neoproterozoic stratigraphy of the northeast Amadeus Basin, Northern Territory. Record 2015-##, Northern Territory Geological Survey.
Preiss WV, Walter MR, Coats RP and Wells AT, 1978. Lithological correlations of Adelaidean glaciogenic rocks in parts of the Amadeus, Ngalia, and Georgina basins. BMR Journal of Australian Geology and Geophysics 3, 43-53.
Walter MR, Veevers JJ, Calver CR and Grey K, 1995. Neoproterozoic stratigraphy of the Centralian Superbasin, Australia. Precambrian Research 73, 173-195.
Wells AT, Ranford LC, Stewart AJ, Cook PJ and Shaw R, 1967. Geology of the north-eastern part of the Amadeus Basin, Northern Territory BMR Report 113, Australia.|16-MAY-23
21611|Dalumbu Sandstone|Name source|Dalumbu Bay on southeastern side of Groote Eylandt, CAPE BEATRICE.|16-MAY-23
21611|Dalumbu Sandstone|Unit history|Formerly mapped as part of the now abandoned 'Groote Eylandt beds' (Plumb and Roberts, 1965, 1992).|16-MAY-23
21611|Dalumbu Sandstone|Geomorphic expression|Dissected palteau of joint-controlled, bare rocky outcrops.|16-MAY-23
21611|Dalumbu Sandstone|Type section locality|Lower boundary stratotype: Bluff Hill area (lat. 13o 59'S, long. 136o 44'E; GR PE877535), where the unit overlies Bartalumba Basalt. Approximately 80m of sandstone above the boundary. Reference area: Because of very gentle dips no single section through the formation exists. The nominated reference area comprises the main body of continuous outcrop of the unit on Groote Eylandt, an area of approximately 900km2, centred at about lat. 14o 05'S, long. 136o 35'E.|16-MAY-23
21611|Dalumbu Sandstone|Extent|Most outcrops on central and southern parts of Groote Eylandt. Also exposed on Connexion Island and southeastern Bickerton Island (PORT LANGDON, CAPE BEATRICE, BLUE MUD BAY and ROPER RIVER).|16-MAY-23
21611|Dalumbu Sandstone|Thickness range|Minimum thickness of ~500-1000m exposed on Groote Eylandt. No stratigraphic top has been recognised.|16-MAY-23
21611|Dalumbu Sandstone|Lithology|White to pink, medium- to coarse-grained, quartz-rich, pebbly (mainly quartz) sandstones with granule lensesl very weathered, ferriginous basalt lava.|16-MAY-23
21611|Dalumbu Sandstone|Depositional environment|Predominantly a braided fluviatile environment. Sand ridges preserved by a thin (<15m) basalt flow probably represent deposition on a shallow shelf during a brief marine incursion across a coastal plain.|16-MAY-23
21611|Dalumbu Sandstone|Relationships and boundaries|Concordantly overlies Bartalumba Basalt, although contact is not exposed. The top of the unit is eroded and overlain unconformably by Cretaceous and Cainozoic rocks and sediments. Based on aeromagnetic evidence, it is intruded by magnetic (probably mafic) dykes.|16-MAY-23
21611|Dalumbu Sandstone|Age reasons|Probably Statherian (Palaeoproterozoic). The Bickerton Rhyolite, low in the Groote Eylandt Group, has been dated by SHRIMP single-zircon U-Pb techniques at ~1815Ma (Pietsch et al. 1994).|16-MAY-23
21611|Dalumbu Sandstone|Correlations|May correlate with the Sly Creek Sandstone of the Tawallah Group.|16-MAY-23
5163|Daly River Group|Name source|Daly River, northwestern Northern Territory.|16-MAY-23
5163|Daly River Group|Unit history|Buldiva Series of Hossfeld (1937) in part, Daly River Limestones of Voisey (1939), Daly River Limestone Group of Noakes (1947).|16-MAY-23
5163|Daly River Group|Constituents|In ascending order Tindall Limestone, Jinduckin Formation, Oolloo Dolostone.|16-MAY-23
5163|Daly River Group|Type section locality|51.5-760.0 m in cored drillhole NTGS 86/1, northeastern Jinduckin 1:100 000, AMG 587327 (latitude 14o09'50"S, longitude 131o23'50"E). Core stored at NTGS Core Library, Darwin.|16-MAY-23
5163|Daly River Group|Extent|Outcrop in Pine Creek, Fergusson River, Katherine, Delamere, Larrimah 1:250 000; subcrop proven on inferred in Cape Scott, Hodgson Downs, Daly Waters, Tranumbirini 1:250 000.|16-MAY-23
5163|Daly River Group|Thickness range|708.5 m in type section; possibly attains 740 m in thickest parts of Daly Basin.|16-MAY-23
5163|Daly River Group|Age reasons|Middle Cambrian (Ordian) to Early Ordovician, based on trilobites and associated fauna of Tindall Limestone, and conodonts of Jinduckin-Oolloo boundary beds (Opik, 1956; Jones, 1971).|16-MAY-23
5163|Daly River Group|References|01/31581; B117; 47/040; B016; 01/31582.|16-MAY-23
5163|Daly River Group|Proposer|Kruse P.D.; originally Noakes (1949)|16-MAY-23
5163|Daly River Group|Status|1|16-MAY-23
21620|Dashwood Gabbro Complex|Name source|Dashwood Creek.|16-MAY-23
21620|Dashwood Gabbro Complex|Unit history|Previously unnamed, described by Glikson (1984).|16-MAY-23
21620|Dashwood Gabbro Complex|Geomorphic expression|Gabbro forms dark rubbly outcrops, felsic halo is a light-coloured recessive unit.|16-MAY-23
21620|Dashwood Gabbro Complex|Type section locality|9km north by east of Glen Helen homestead near GR 226500 7409500 Glen Helen 1:100 000 Sheet area.|16-MAY-23
21620|Dashwood Gabbro Complex|Extent|Large outcrop southwest of Mount Zeil, possibly smaller plugs south and southeast of Redbank homestead.|16-MAY-23
21620|Dashwood Gabbro Complex|Lithology|Zoned bodies of gabbro and dolerite rimmed by felsic rocks, retrogressed to greenschist or amphibolite facies.|16-MAY-23
21620|Dashwood Gabbro Complex|Relationships and boundaries|Intrudes Glen Helen Metamorphics.|16-MAY-23
21620|Dashwood Gabbro Complex|Structure and Metamorphism|Largely undeformed except for some deformation along one side the RTZ. Markedly hydrated under upper greenschist to lower amphibolite facies conditions.|16-MAY-23
21620|Dashwood Gabbro Complex|Age reasons|Younger than 1670 Ma (age of Glen Helen Metamorphics, Black & Shaw, 1992).|16-MAY-23
21620|Dashwood Gabbro Complex|Defn author|R.D. Shaw & R.G. Warren, 7 May 1992.|16-MAY-23
21620|Dashwood Gabbro Complex|Comments|This 'definition' is missing the details of references mentioned in the synonymy and age, and shows no signs on the card of having been approved.|16-MAY-23
35396|Dead Bullock Formation|Name source|Dead Bullock Soak, a small creek and waterhole on north side of Ditjiedoonkuna Hills (alternatively known as Schist Hills) at (GDA94) 20deg31'S, 129deg56'E, THE GRANITES.|16-MAY-23
35396|Dead Bullock Formation|Unit history|Mount Charles Beds and Nongra Beds (Blake et al 1975) in part; 'Schist Hills Formation', 'Schist Hills Iron Member', 'Seldom Seen Schist' and 'Orac Formation' of Lovett et al (1993); 'Lower Blake beds', 'Magpie schist', 'Callie boudin chert', 'Callie host unit', 'Davidson beds', 'Schist Hills formation', 'Orac formation', 'lower Orac chert', 'Dead Bullock member', 'Schist Hills iron member', 'Colgate schist', 'Manganiferous chert unit', 'Seldom Seen schist' and upper 'Blake beds' of Smith et al (1998); 'Schist Hill Formation' of Ferenczi and Ahmad (1998); MacFarlane Peak Group in part and Twigg Formation in part (Hendrickx et al 2000); 'Schist Hill Iron Member', 'Dead Bullock Member', 'Callie Formation' in Wygralak et al (2005).|16-MAY-23
35396|Dead Bullock Formation|Constituents|In ascending order Ferdies Member and Callie Member; these together account for all known outcrop of Dead Bullock Formation. Numerous informal subunits (above) described in detail from drilling and open pit mapping are here discounted.|16-MAY-23
35396|Dead Bullock Formation|Geomorphic expression|Discontinuous ferruginous strike ridges, low ferricrete rises, rubbly chert ridges.|16-MAY-23
35396|Dead Bullock Formation|Type section locality|Ferdies Member: rare outcrop of deformed feldspathic sandstone near Officer Hill at (GDA94) 20deg44'30''S, 129deg33'30''E, THE GRANITES; magnetic quartose psammite east of McFarlanes Peak Range at (GDA94) 20deg18'00''S, 129deg26'30''E, THE GRANITES. Callie Member: exposures at Dead Bullock Soak operations, centred on (GDA94) 20deg31'S, 129deg56'E, THE GRANITES; The Granites gold mine at (GDA94) 20deg32'S, 130deg19'E, THE GRANITES; outcrops referred to as 'Lightning Ridge' at (GDA94) 19deg48'S, 129deg18'E, TANAMI.|16-MAY-23
35396|Dead Bullock Formation|Type section locality|Apertawonga Range (GDA94) 20deg14'S, 129deg33'E, THE GRANITES provides good outcrop of contorted chert and siltstone of Callie Member. Greywacke of Killi Killi Formation crops out sporadically to northwest, appearing to overlie Dead Bullock Formation.|16-MAY-23
35396|Dead Bullock Formation|Extent|Widely distributed throughout THE GRANITES, western TANAMI, and western MOUNT SOLITARIE; similar rock types recognised in BILLILUNA.|16-MAY-23
35396|Dead Bullock Formation|Thickness range|No lower contact observed. Apertawonga Range exposures (type locality) consist of approximately 600 m of section. Minimum 400 m recognised at 'Lightning Ridge'. Exposures at Dead Bullock Soak are contained within an anticlinorium that has complications due to hinge thickening and layer-parallel intrusive rocks, but formation thickness on less-deformed northern limb is estimated to be 375 m, although lower Ferdies Member is folded out and not preserved. An estimate from logged drillcore at Dead Bullock Soak is approximately 500-510 m (Lambeck 2004).|16-MAY-23
35396|Dead Bullock Formation|Lithology|Outcrops commonly silicified to form massive and laminated chert (eg Apertawonga Range, 'Lightning Ridge'). Ferdies Member: sandy siltstone, siltstone, fine quartz sandstone and feldspathic sandstone, interbedded with shale and siltstone, occasional chert nodule-rich layers in siltstone; commonly contains magnetite. Callie Member: generally fine siliciclastic and chemical sedimentary rocks; buff to grey, massive to thinly bedded, laminated siltstone, black carbonaceous siltstone, thinly bedded chert, manganiferous chert, banded ironstone, nodular chert in siltstone; chert nodules more common near top.Amphibolite facies rocks at The Granites include amphibole-biotite schist, andalusite-biotite-almandine schist, hornblende-cummingtonite schist, massive almandine-cummingtonite schist, calc-silicate and chert bands and graphitic biotite-andalusite schist.|16-MAY-23
35396|Dead Bullock Formation|Depositional environment|Generally deep water with varying sediment input. Progression from Ferdies Member to Callie Member represents decrease in siliciclastic sediment supply in transgressive setting.|16-MAY-23
35396|Dead Bullock Formation|Relationships and boundaries|Lower boundary not observed. Upper boundary: siltstone of Dead Bullock Formation grades upward into alternating layers of fine greywacke and siltstone of Killi Killi Formation. At The Granites, first psammitic bed overlying graphitic schist determines upper stratigraphic contact with overlying Killi Killi Formation.|16-MAY-23
35396|Dead Bullock Formation|Age reasons|Orosirian. A tuff intercalated with Callie Member has a SHRIMP U-Pb zircon age of 1838 ± 4 Ma (Cross et al 2005). Youngest detrital zircon populations in samples of the overlying Killi Killi Formation suggest maximum deposition age of ~1840 Ma (Cross et al 2003). Dead Bullock Formation intruded by 1815 ± 4 Ma granodiorite ('Bunkers Granodiorite' of Smith (2001), now an unnamed granodiorite in Grimwade Suite, Bunkers pit, The Granites gold mine; Smith (2000)).|16-MAY-23
35396|Dead Bullock Formation|Correlations|May be coeval with parts of lower Ooradidgee Group of Tennant Region and Lander Rock beds of Arunta Region.|16-MAY-23
35396|Dead Bullock Formation|Proposed publication|Crispe AJ and Vandenberg LC, in press. Geology of the Tanami Region, Northern Territory. NTGS Report.|16-MAY-23
35396|Dead Bullock Formation|Comments|Formation is locally intruded by mafic sills that contribute to its distinct regional magnetic signature; intrusions appear extensive.|16-MAY-23
35396|Dead Bullock Formation|References|Blake DH, Hodgson IM and Smith PA, 1975. Geology of the Birrindudu and Tanami 1:250 000 sheet areas, Northern Territory. Bureau of Mineral Resources, Australia, Report 174.Cross A, Claoué-Long J and Crispe A, 2003. Summary of results. Joint NTGS-GA geochronology project: Tanami Region 2001-2002. Northern Territory Geological Survey, Record 2003-006.Cross AJ, Fletcher IR, Crispe AJ, Huston DL and Williams N, 2005. New constraints on the timing of deposition and mineralisation in the Tanami Group: in `Annual Geoscience Exploration Seminar (AGES) 2004. Record of abstracts.¿ Northern Territory Geological Survey, Record 2004-001.Ferenczi PA and Ahmad M, 1998. Geology and mineral deposits of The Granites-Tanami and Tennant Creek Inliers, Northern Territory. AGSO Journal of Australian Geology and Geophysics 17, 19-33.Hendrickx MA, Slater KR, Crispe AJ, Dean AA, Vandenberg LC and Smith JB, 2000. Palaeoproterozoic stratigraphy of the Tanami Region: regional correlations and relation to mineralisation ¿ preliminary results. Northern Territory Geological Survey, Record GS2000-13.Lambeck A, 2004. Sequence stratigraphic interpretation at Callie mine, Tanami Desert, Northern Territory. Geoscience Australia, Professional Opinion 2004/3.Smith JB, 2000. NTGS-AGSO Geochronology Project, Report 3. Geoscience Australia, Professional Opinion 2000/27.Smith JB, 2001. Summary of results. Joint NTGS-AGSO Age Determination Program 1999-2001. Northern Territory Geological Survey, Record 2001-007.Smith MEH, Lovett DR, Pring PI and Sando BG, 1998. Dead Bullock Soak gold deposits: in Berkman DA and Mackenzie DH (editors) `Australian and Papua New Guinean mineral deposits¿. Australasian Institute of Mining and Metallurgy, Monograph 22, 449-460.Wygralak AS, Mernagh TP, Huston DL and Ahmad M, 2005. Gold mineral system of the Tanami Region. Northern Territory Geological Survey, Report 18.|16-MAY-23
35396|Dead Bullock Formation|Parent|Tanami Group|16-MAY-23
35396|Dead Bullock Formation|Proposer|Marc Hendrickx, after Hendrickx et al (2000).|16-MAY-23
23539|Deep Bore Metamorphics|Name source|Deep Bore in southwestern HUCKITTA 1:250 000 mapsheet, Northern Territory (135.5828degreesE 22.6817degreesS (GDA 2020)).|16-MAY-23
23539|Deep Bore Metamorphics|Unit history|Previously Deep Bore Metamorphics metacarbonate and metamudstone unit of Shaw et al (1985) and Freeman et al (1986).|16-MAY-23
23539|Deep Bore Metamorphics|Constituents|Cackleberry Metacarbonate, Ledan Schist, Utopia Quartzite members.|16-MAY-23
23539|Deep Bore Metamorphics|Geomorphic expression|Weathered, isolated broad rises, low hills and ridges.|16-MAY-23
23539|Deep Bore Metamorphics|Type section locality|No single outcrop contains all informal and formal members. Access to the outcrops are via public roads and private tracks. Some off-track driving/walking might be required. Isolated outcrops of metagreywacke paragneisses (around 135.5855degreesE 22.7116degreesS (GDA2020)) are a type locality for the unit.  Reference localities include: mica-bearing metasandstones (around 135.5643degreesE 22.7111degreesS (GDA2020)); Cackleberry Metacarbonate (around 135.5834degreesE 22.7113degreesS (GDA2020)) in the eastern Mopunga Range in JINKA 1:100 000 mapsheet; low, isolated outcrops of Ledan Schist southwest of 9 Mile Bore (eg around 135.0579degreesE 22.5125degreesS (GDA2020)) and ridges; and, rises of Utopia Quartzite outcrop southeast of Dneiper Homestead (eg at 135.1979degreesE 22.6262degreesS (GDA2020)) in southwestern HUCKITTA (Weisheit et al in prep).|16-MAY-23
23539|Deep Bore Metamorphics|Extent|The unit outcrops in the Deep Bore Domain north of the Delny Shear Zone and south of the Georgina Basin in south-central and western HUCKITTA (~135.0388-135.9063degreesE and ~22.4984-22.8391degreesS (GDA2020)). Ledan Schist and Utopia Quartzite are recognised in northwestern ALCOOTA north of Delmore Downs homestead and possibly in BARROW CREEK.|16-MAY-23
23539|Deep Bore Metamorphics|General description|Constituent units include metagreywacke paragneisses, mica-bearing metasandstones, Cackleberry Metacarbonate, Ledan Schist, Utopia Quartzite (see individual definition cards for last three members). In the Mopunga Range area, the units (except Ledan Schist and Utopia Quartzite) are migmatitic, complexly interlayered and folded, and intruded by Palaeoproterozoic meta-igneous rocks. Further west, Ledan Schist and Utopia Quartzite also occur interlayered with paragneisses at the 10-100 m-scale. The metamorphic grade possibly decreases from east to west to amphibolite facies.|16-MAY-23
23539|Deep Bore Metamorphics|Thickness range|Not observed in type area. Estimated to be much less than 2 km; ranging in the 100 m-scale. The thickness of original sedimentary units, or their stratigraphic order and an absolute younging direction cannot be easily determined because of structural and metamorphic overprinting.|16-MAY-23
23539|Deep Bore Metamorphics|Lithology|Amphibolite- to granulite-facies, migmatitic metagreywacke paragneiss with less abundant aluminous metasandstones, metacarbonates, schists and quartzite. Locally retrogressed to amphibolite- and greenschist-facies rocks. See individual definition cards for named members. Unnamed members: The metagreywacke paragneisses subunit comprises layered, fine- to medium-grained cordierite-quartz-K-feldspar-biotite+/-plagioclase-garnet+/-orthopyroxene granulite facies migmatites; fine- to medium-grained, quartz-feldspar-biotite+/-garnet+/-sillimanite paragneisses; rare biotitites, sapphirine-bearing rocks, hornblendites interpreted as alteration products. The mica-bearing metasandstones comprises massive, microcrystalline quartzites and very fine- to fine-grained quartz-rich schists. Variable 5-20 vol% foliated biotite and muscovite. Rare quartz-plagioclase-K-feldspar-biotite gneiss tentatively interpreted as meta-volcaniclastic rock.|16-MAY-23
23539|Deep Bore Metamorphics|Depositional environment|Unimodal detrital zircon spectra indicate a metavolcaniclastic component to the Deep Bore Metamorphics. The youngest parts of the metasedimentary packages were deposited contemporaneously with intrusion of igneous rocks at ca 1.79 Ga indicative of a back-arc basin (Baikal Supersuite). Occurrence of metacarbonate rocks within a dominantly metamudstone, metasandstone succession indicate (shallow) marine conditions.|16-MAY-23
23539|Deep Bore Metamorphics|Relationships and boundaries|One of the oldest preserved rock units in HUCKITTA. Intruded by and included as xenoliths in rocks of the Black Label Suite, Baikal Supersuite, Marshall Granite. Locally overlain by and faulted against rocks of the Georgina Basin.|16-MAY-23
23539|Deep Bore Metamorphics|Identifying features|These are the only metasedimentary rocks in the Deep Bore Domain in HUCKITTA (north of the Delny Shear Zone and west of the Elua Range).|16-MAY-23
23539|Deep Bore Metamorphics|Structure and Metamorphism|Schistose to gneissic locally mylonitic and faulted, compositionally layered, migmatitic in the central and eastern occurrences, isoclinally folded at cm-scale. Amphibolite to granulite facies; retrogressed proximal to and within shear zones.|16-MAY-23
23539|Deep Bore Metamorphics|Age reasons|Deposition as early as ca 1.82 Ga, with some components as young as ca 1.79 Ga. Unimodal detrital zircon populations at 1822 +/- 9 Ma, 1819 +/- 9 Ma (LA-ICP-MS, Reno et al 2018), 1808 +/- 5 Ma (SHRIMP, Kositcin et al 2018), 1805 +/- 7 Ma (SHRIMP, Scrimgeour et al 2001). The youngest U-Pb zircon maximum depositional age is 1791 +/- 6 Ma (SHRIMP, Kositcin et al 2018) and the oldest metamorphic zircon growth was at 1787 +/- 11 Ma (LA-ICP-MS, Reno et al 2018).|16-MAY-23
23539|Deep Bore Metamorphics|Correlations|Interpreted to be age-equivalent to Bonya, Kanandra, and Perenti metamorphics of the Aileron Province.|16-MAY-23
23539|Deep Bore Metamorphics|Alteration and Mineralisation|Schists and gneisses are moderately to strongly weathered; quartzite is fresh to weakly weathered. Rare biotitites, sapphirine-bearing rocks and hornblendites may be alteration products. K-feldspar-quartz alteration and muscovitisation may occur at contacts with Marshall Granite. Silicification is common close to regional faults and shear zones. Around Molyhil W-Mo deposit, Cackleberry Metacarbonate is host to exogene epigenetic mineralisation (eg McGloin and Weisheit 2022).|16-MAY-23
23539|Deep Bore Metamorphics|Geophysical Expression|No clear magnetic, gravity or radiometric character due to the lack of continuous outcrop and dominance of meta-igneous rocks in the area. However, locally associated with magnetic low and high trends.|16-MAY-23
23539|Deep Bore Metamorphics|Defn author|Anett Weisheit, Barry Reno, Eloise Beyer, Pablo Farias (NT Department of Industry, Tourism and Trade, Northern Territory Geological Survey) 3-MAY-2022.|16-MAY-23
23539|Deep Bore Metamorphics|References|Freeman MJ, Black LA, Offe LA, Senior BR, Shaw RD, Shergold JH, Simpson CJ, Walter MR, Warren RG, Donnellan N, Horsfall CJ, Laurie JR and Walley AM, 1986. Huckitta, Northern Territory (Second Edition). 1:250 000 geological map series, SF 53-11. Northern Territory Geological Survey, Darwin.  **Kositcin N, Reno BL and Beyer EE, 2018. Summary of results. Joint NTGS-GA geochronology project: Aileron Province, July 2015-June 2016. Northern Territory Geological Survey, Record 2018-005.  **Reno BL, Beyer EE, Thompson JM and Meffre S, 2018. NTGS laser ablation ICP-MS zircon petrochronology project: Aileron Province, Jinka and Dneiper 1:100 000 mapsheets. Northern Territory Geological Survey, Record 2018-003.  **Scrimgeour IR, Smith JB and Raith J, 2001. Palaeoproterozoic high-T, low-P metamorphism and dehydration melting in metapelites from the Mopunga Range, Arunta Inlier, central Australia. Journal of Metamorphic Geology 19, 739-757.  **Shaw, R.D., Warren, R.G., Freeman, M.J., 1985, Stratigraphic definitions of named units in the Arunta Block, Northern Territory, 1979-82., Bureau of Mineral Resources, Australia, Report, 260.  **Weisheit A et al, in prep. Huckitta, Northern Territory. 1:250 000 geological map series explanatory notes, SF53-11. Northern Territory Geological Survey, Darwin.|16-MAY-23
26516|Delmore Metamorphics|Name source|After 'Delmore Downs' Station which covers part of outcrop area. Station is in central-eastern Alcoota 1:250 000 Sheet area, SF53-10, Australian map Grid.|16-MAY-23
26516|Delmore Metamorphics|Type section locality|Centred on 473E, 7518N AMG (metric) and up to 1.5 km away; to the east of Ledan Schist, type section; 8 km west of 'Delmore Downs' homestead.|16-MAY-23
26516|Delmore Metamorphics|Extent|Crops out from near Mount Ida northwards to beyond Western Watering Point, 'Delmore Downs' Station.|16-MAY-23
26516|Delmore Metamorphics|Lithology|Calc-silicate rock, microcline-bearing pelitic gneiss, epidote quartzite and anthophyllite-chlorite-cordierite rock, and rare epidosite both exposed in type area, but better exposed at GR4707E, 75132N.|16-MAY-23
26516|Delmore Metamorphics|Relationships and boundaries|Unconformably overlain by the Ledan Schist. Thought to possibly overlie the Delney Metamorphics although boundary not exposed. Intruded by the Copia, Ida and possibly the Mount Swan Granites.|16-MAY-23
26516|Delmore Metamorphics|Identifying features|High biotite content and dark grey appearance of exposures of pelitic units. In thin section characterised by generally high microcline content.|16-MAY-23
26516|Delmore Metamorphics|Correlations|Tentative correlations: Possibly equivalent to the upper part of the sequence in the Bonya Creek area of the Huckitta 1:250 000 Sheet area. Tentatively correlated with the Mount Stafford Beds.|16-MAY-23
26516|Delmore Metamorphics|Proposed publication|BMR Report|16-MAY-23
26516|Delmore Metamorphics|Name first published by|Shaw R.D., Warren R.G., Kopras J., Green D.E., 1975|16-MAY-23
5354|Delny Gneiss|Name source|After 'Delny' (GR 4813E, 7506N AMG metric) northeast of outcrop area. 'Delny' homestead has been abandoned. It is situated 11 km south of 'Delmore Downs' homestead, eastern Alcoota 1:250 000 Sheet area, SF53-10, Australian Map Grid.|16-MAY-23
5354|Delny Gneiss|Type section locality|Centred on 4665E, 7506N, AMG (metric) and up to 2 km to south.|16-MAY-23
5354|Delny Gneiss|Extent|Extends west and northwest from Dingo Creek near Delny Homestead to Boomerang Bore (GR 430E, 75145N, AMG, metric).|16-MAY-23
5354|Delny Gneiss|Lithology|Leucocratic biotite-muscovite-quartz-gneiss with clots of muscovite, biotite-muscovite and muscovite-biotite schists. Psammites and pelites, amphibolite, very minor calc-silicate gneiss. All exposed in type area.|16-MAY-23
5354|Delny Gneiss|Relationships and boundaries|Possibly overlies the Mapata Gneiss unconformably (suggested by marked change in lithology). Intruded by the Copia, Ida and Crooked Hole Granites and Woodgreen Granite Complex.|16-MAY-23
5354|Delny Gneiss|Identifying features|Most common leucocratic gneiss contains conspicuous muscovite clots.|16-MAY-23
5354|Delny Gneiss|Correlations|Tentative correlations: Possibly equivalent to the upper part of the sequence in the Bonya and Jervois areas.|16-MAY-23
5354|Delny Gneiss|Proposed publication|BMR Report|16-MAY-23
5354|Delny Gneiss|Name first published by|Shaw R.D., Warren R.G., Kopras J., Green D.E., 1975|16-MAY-23
79232|Denara Orthogneiss|Name source|After Denara Bore (630731mE 7460875mN, GDA94, Zone53) in Jervois Range 1:100 000 mapsheet, Northern Territory.|16-MAY-23
79232|Denara Orthogneiss|Unit history|Formerly pCd, Pzr, and Pg on second edition Huckitta 1:250 000 mapsheet (Freeman et al 1986).|16-MAY-23
79232|Denara Orthogneiss|Geomorphic expression|Scattered bouldery outcrops, some small hills and pavements.|16-MAY-23
79232|Denara Orthogneiss|Type section locality|Approximately 9 km northeast of Denara Bore, at 638358mE 7466068mN (GDA94, Zone53).Accessible via private tracks.|16-MAY-23
79232|Denara Orthogneiss|Extent|Dominant lithology in the southern portion of Jervois Range 1:100 000 mapsheet over an area of about 40 x 15km.|16-MAY-23
79232|Denara Orthogneiss|General description|Migmatitic orthogneiss with clearly developed migmatitic textures, locally overprinted by gneissic fabrics, common melanocratic and leucocratic zones, local biotite-rich schistose melanocratic zones, locally mylonitic and ultramylonitic.|16-MAY-23
79232|Denara Orthogneiss|Lithology|Migmatitic orthogneiss; preserves evidence for partial melting and melt accumulation. Outcrop comprises 1-10 cm-thick leucocratic and melanocratic bands of biotite-rich and biotite-poor orthogneiss, and leucocratic zones resultant from partial melting and melt migration within the orthogneiss.|16-MAY-23
79232|Denara Orthogneiss|Depositional environment|Continental margin environment, either arc cordillera or back arc basin, or derived from melting of pre-existing crust that formed in a continental margin environment.|16-MAY-23
79232|Denara Orthogneiss|Relationships and boundaries|Contacts with other units are not exposed. Interpreted to be source for unnamed granite, which forms a km-wide body in the subsurface within Denara Orthogneiss. Mylonitic versions occur in Delny Shear Zone, which is a bounding structure to Denara Orthogneiss. Mylonitic contact with Yambla Gneiss. Interpreted to be nonconformably overlain by possible Yackah beds.|16-MAY-23
79232|Denara Orthogneiss|Identifying features|Strongly foliated and compositionally layered quartzofeldspathic migmatite; multiple generations of leucosomes are both deformed and cross-cut deformation.|16-MAY-23
79232|Denara Orthogneiss|Structure and Metamorphism|Strongly gneissic, preserving at least 7 deformation fabrics that are locally developed. Preserves variably deformed migmatite structures related to syn-anatectic partial melt generation, migration, and accumulation.|16-MAY-23
79232|Denara Orthogneiss|Age reasons|Crystallisation of igneous protolith at 1779 ± 5 Ma (Kositcin et al 2015); metamorphic zircon growth at 1749 ± 4 Ma (Kositcin et al 2015); metamorphic monazite growth at 1749 ± 10 Ma and 1723 ± 4 Ma (Reno et al 2016). Unnamed granite emplacement and crystallisation by 1766 ± 14 Ma (Beyer et al 2018).|16-MAY-23
79232|Denara Orthogneiss|Correlations|Protolith emplacement coeval with rocks of the Baikal Supersuite.|16-MAY-23
79232|Denara Orthogneiss|Alteration and Mineralisation|Altered to biotite schist in locations associated with m-scale quartz veins related to fluid infiltration; local intensive K-feldspar-quartz alteration and hematitisation. No known economic mineralisation.|16-MAY-23
79232|Denara Orthogneiss|Geophysical Expression|Irregular magnetic high and low signals with irregular magnetic high trends; gravity high and low signals; radiometric high signal.|16-MAY-23
79232|Denara Orthogneiss|Geochemistry|Weakly to strongly peraluminous I-type syenogranite to monzogranite to granodiorite.|16-MAY-23
79232|Denara Orthogneiss|Defn author|Anett Weisheit, Barry Reno, Eloise Beyer (Northern Territory Geological Survey) 27-JUN-2018.|16-MAY-23
79232|Denara Orthogneiss|Proposed publication|Weisheit A, Reno BL and Beyer EE, in review. Jervois Range Special, Northern Territory. 1:100 000 geological map explanatory notes, 6152 and part 6252. Northern Territory Geological Survey, Darwin.|16-MAY-23
79232|Denara Orthogneiss|References|Beyer EE, Reno BL, Weisheit A, Whelan JA, Thompson JM, Meffre S and Woodhead JD, 2018. Summary of results. NTGS laser ablation ICP-MS U-Pb-Hf geochronology project: selected samples from JERVOIS RANGE 1:100 000 and TOBERMOREY 1:250 000 mapsheets, Aileron and Irindina provinces, January 2014 - December 2016. Northern Territory Geological Survey, Record 2018-001.   **Freeman MJ, Black LA, Offe LA, Senior BR, Shaw RD, Shergold JH, Simpson CJ, Walter MR, Warren RG, Donnellan N, Horsfall CJ, Laurie JR and Walley AM, 1986. Huckitta, Northern Territory (Second Edition). 1:250 000 geological map series, SF 53-11. Northern Territory Geological Survey, Darwin  **Kositcin N, Reno BL and Whelan JA, 2015. Summary of results. Joint NTGS-GA geochronology project: Arunta Region, July 2014 - June 2015. Northern Territory Geological Survey, Record 2015-007.  **Reno BL, Whelan JA, Weisheit A, Kraus S, Beyer EE, Meffre S and Thompson J, 2016. Summary of Results. NTGS laser ablation ICP-MS in situ monazite and xenotime geochronology project: Arunta Region, Jervois Range 1:100 000 mapsheet. Northern Territory Geological Survey, Record 2016-004.|16-MAY-23
5379|Depot Creek Sandstone|Unit history|This unit was first published by White and others (1963) and later more fully defined by Walpole and others (1968), as the Depot Creek Sandstone Member of the Buldiva Sandstone, Tolmer Group. As it is an extensive, individually mappable unit, its status is now elevated from member to formation, and the name Buldiva Sandstone is discarded.|16-MAY-23
5379|Depot Creek Sandstone|Type section locality|Walpole and others (1968) give a 'reference area' [assume this means 'type area']  as Depot Creek, NE of Douglas homestead, lat. 13deg 10' S, long.131deg 35'E. They also say 'better exposures in Umbrawarra Gorge and E. of Buldiva [?Reference areas].|16-MAY-23
5379|Depot Creek Sandstone|Proposed publication|Dundas D.L., Edgoose C.J., Fahey G.M., Fahey J.E., in prep - Explanatory Notes for Daly River (5070). Northern Territory Geological Survey 1:100 000 Geological Map Series (Darwin: Northern Territory Government Printer)|16-MAY-23
5379|Depot Creek Sandstone|References|Walpole, B.P., Crohn, P.W., Dunn, P.R., Randal, M.A., 1968. Geology of the Katherine-Darwin Region, Northern Territory. BMR Bulletin 82.|16-MAY-23
5434|Devils Marbles Granite|Name source|The Devils Marbles on the Stuart Highway 9 km northeast of Wauchope, GR 230260, Wauchope 1:100 000 Sheet area, Bonney Well 1:250 000 Sheet area.|16-MAY-23
5434|Devils Marbles Granite|Type section locality|The Devils Marbles on the Stuart Highway, where the unit forms piles of large spheroidal boulders: at latitude 20o34'S, longitude 134o15'E.|16-MAY-23
5434|Devils Marbles Granite|Extent|In vicinity of the Devils Marbles; outcrop area covers about 15 km2.|16-MAY-23
5434|Devils Marbles Granite|Lithology|Medium to coarse muscovite-biotite granite (adamellite) with slightly megacrystic feldspar (microcline).|16-MAY-23
5434|Devils Marbles Granite|Relationships and boundaries|Intrudes the Kurinelli Sandstone and Taragan Sandstone of the Ooradidgee Subgroup and Unimbra Sandstone of the Wauchope Subgroup, Hatches Creek Group.|16-MAY-23
5434|Devils Marbles Granite|Age reasons|Older than 1540 m.y. (K-Ar biotite age), and possibly similar in age to the Elkedra Granite, Rb-Sr whole rock age of which is approximately 1640 m.y.|16-MAY-23
5434|Devils Marbles Granite|Comments|Remarks: Well defined granite pluton which postdates the main folding of the Hatches Creek Group. Name used informally by Sullivan (BMR Bulletin 4, 1952).|16-MAY-23
5434|Devils Marbles Granite|Defn Reference|86/25362|16-MAY-23
5434|Devils Marbles Granite|Status|Previously named but not defined|16-MAY-23
21653|Dhalinybuy Granite|Name source|Dhalinybuy outstation (AMG PG500270), Arnhem Bay 1:250 000 scale map sheet area.|16-MAY-23
21653|Dhalinybuy Granite|Unit history|Outcrops now mapped as this unit were previously not differentiataed from the "Spencer Creek Volcanics" by Dunnet (1965).|16-MAY-23
21653|Dhalinybuy Granite|Geomorphic expression|The main outcrops comprise rounded weathered tors and boulders, surrounded by low scrub.|16-MAY-23
21653|Dhalinybuy Granite|Type section locality|A type area is assigned to entire outcrop, centred on latitude 12o17'15"S, longitude 136o26'30"E (AMG PG568412).|16-MAY-23
21653|Dhalinybuy Granite|Extent|Small area on the eastern margin of Arnhem Bay 1:250 000 scale map sheet area; specifically area 15 km northeast of Dhalinybuy outstation along small tributary creeks to Cato River.|16-MAY-23
21653|Dhalinybuy Granite|Lithology|Massive to foliated, pink to green, medium- to coarse-grained, equigranular to porphyritic, quartz-K-feldspar-biotite granite. Plagioclase and garnet are minor localised components. Localised mylonite lenses.|16-MAY-23
21653|Dhalinybuy Granite|Relationships and boundaries|It is inferred to intrude the Bradshaw Complex, and is overlain unconformably by the Yanungbi Volcanics and Gove Sandstone of the Spencer Creek Group. The contact with the Yanungbi Volcanics is notable for a relatively resistant linear ridge, comprised of banded and autobrecciated rhyolite adjacent to coarse-grained granite. Neither rock-type shows evidence of recrystallisation or metamorphism. This is interpreted as the base of a flow unit, sitting immediately above the granite with unconformity. Where the Yanungbi Volcanics is absent, the Dhalinybuy Grnaite is unconformably overlain by lithic sandstones of the Gove Sandstone.|16-MAY-23
21653|Dhalinybuy Granite|Age reasons|Palaeoproterozoic (Statherian). The maximum inferred age is that of the Bradshaw Complex, which it is thought to intrude. Minimum age constraint is the inferred age of the Yanungbi Volcanics, which are interpreted to be a comagmatic equivalent of the Latram Granite of ~1710 Ma (Rawlings and othes, in prep.). Also overlain by the Cato Volcanics of similar age.|16-MAY-23
21653|Dhalinybuy Granite|Correlations|Probably comagmatic with the Giddy and Bukudal Granites, which may in fact connect at depth.|16-MAY-23
21653|Dhalinybuy Granite|Proposed publication|Arnhem Bay-Gove 1:250 000 Geological Map Series, Northern Territory, National Geoscience Mapping Accord, Explanatory Notes (Rawlings and others, in prep.).|16-MAY-23
21653|Dhalinybuy Granite|Category|2|16-MAY-23
21653|Dhalinybuy Granite|Defn approved by|Brakel A.T./Haines P.W.|16-MAY-23
21653|Dhalinybuy Granite|Proposer|Rawlings D.J.|16-MAY-23
21653|Dhalinybuy Granite|Reserved? Yes/No|Yes|16-MAY-23
21654|Dhunganda Formation|Name source|Dhunganda outstation (AMG NF360753), Arnhem Bay 1 |16-MAY-23
21654|Dhunganda Formation|Unit history|Comprises the lower half of the "Ritarango beds" of Dunnet (1965) and Plumb and Roberts (1992).|16-MAY-23
21654|Dhunganda Formation|Geomorphic expression|Sandstone-dominated parts of the formation form resistant and upstanding ridges, while the igneous-mudstone-volcaniclastic association is typically recessive.|16-MAY-23
21654|Dhunganda Formation|Type section locality|The southwestern perimeter of Ritarango Gap, around latitude 12o58'S, longitude 135o32'E (Arnhem Bay mapsheet area). The base of the section is AMG NF560680 and the top is NF581663. Absolute base and top of sequence are not exposed, so no boundary stratotypes are indicated.|16-MAY-23
21654|Dhunganda Formation|Extent|Small area bordering on southern Arnhem Bay and northern Blue Mud Bay 1:250 000 scale mapsheet areas. Along with the Ritarango Formation, comprises the core of the Mitchell Range, centred on Ritarango Gap.|16-MAY-23
21654|Dhunganda Formation|Thickness range|>500 m.|16-MAY-23
21654|Dhunganda Formation|Lithology|Strongly deformed white fine- to coarse-grained quartzose sandstone and minor conglomeratic lithic sandstone, felsic and mafic igneous and associated volcaniclastic rocks, and mudstones. Sandstones are silicified, medium- to very thick-bedded, trough cross-bedded or rarely rippled. Conglomeratic sandstone is common near the base and contains pebbles and cobbles of massive quartz and lesser quartzite and felsic igneous rock. Felsic igneous rock is porphyritic K-feldspar-quartz-albite rhyolite, grading locally into dolerite and hybrid rock. Volcaniclastic rocks include primary and redeposited hyaloclastite and autoclastite breccia, and epiclastic sandstone and mudstone. Localised coarsening-upward cycles of mudstone and fine- to medium-grained sandstone, with common ripples and mudclasts and lesser hummocky cross-beds and tool marks. All rock-types are commonly sheared.|16-MAY-23
21654|Dhunganda Formation|Depositional environment|Lower part of sequence: high-energy, shallow water, fluviatile to deltaic sedimentary rocks. Upper part of sequence: volcanic and intrusive igneous rocks; moderately deep water to emergent sedimentary rocks.|16-MAY-23
21654|Dhunganda Formation|Relationships and boundaries|Basal formation of the Donydji Group. Apparently unconformably overlies the Mirarrmina Complex and is in turn unconformably? overlain by the Ritarango Formation. The lower contact is not exposed, but likely basal coarse-grained conglomeratic lithic sandstones of the Dhunganda Formation lie adjacent to granitic and metamorphic rocks of the Mirarrmina Complex at NF587912 and NF600858, with no evidence of a fault. The upper contact was not observed, but corresponds to a significant change in rock-types and structural characteristics, possibly related to a sedimentological break and period of tectonism. The Ritarango Formation comprises considerably coarser-grained and less-mature siliciclastic rocks with an apparently lower degree of deformation. The underlying Dhunganda Formation is made up of strongly-deformed interlayered sandstone, mudstone, volcaniclastic and bimodal igneous rocks. In most places this boundary has been intruded by a large mafic sill, obscuring the contact.|16-MAY-23
21654|Dhunganda Formation|Age reasons|Palaeoproterozoic (Statherian). The maximum age is poorly constrained by an inferred age of ~1870 Ma for the underlying Mirarrmina Complex (based on correlation with Bradshw Complex in eastern Arnhem Bay/western Gove mapsheet areas; Plumb and Roberts, 1992). Its minimum age is constrained by ~1710 Ma age determinations for concordant igneous units at the top of the Donydji Group (Rawlings and others, in prep.). Most likely correlation according to Rawlings (1994) is with lower Tawallah Group, suggesting the best estimate of this formations age is ~1800 Ma or slightly younger.|16-MAY-23
21654|Dhunganda Formation|Correlations|Rawlings and others (in prep.) and Rawlings (1994) suggest correlation with the lower parts of the Tawallah and Katherine River Groups in the southern and western parts of the McArthur Basin respectively. Similarly, it may well correlate with the Alyangula Subgroup of the Groote Eylandt Group. These correlations are based on geochemical, petrological, lithostatigraphic and geochronological constraints, and the physical form of igneous units.|16-MAY-23
21654|Dhunganda Formation|Proposed publication|Arnhem Bay-Gove 1:250 000 Geological Map Series, Northern Territory, National Geoscience Mapping Accord, Explanatory Notes (Rawlings and others, in prep.).|16-MAY-23
21654|Dhunganda Formation|Comments|The "Ritarango beds" of Dunnet (1965) and Plumb and Roberts (1965, 1992) were inadequately defined with no type section. The reference locality nominated was too broad to be useful. The need to subdivide them was brought about by the identification of significant mid-sequence changes in rock-type and structural characteristics, thought to be related to a significant sedimentological break and period of tectonism (unconformity). Most of the areas previously mapped as Ritarango beds are now mapped as Ritarango Formation, and a small mappable area of distinctly different (older) outcrop has been extracted and mapped as Dhunganda Formation.|16-MAY-23
21654|Dhunganda Formation|Category|2|16-MAY-23
21654|Dhunganda Formation|Defn approved by|Brakel A.T./Haines P.W.|16-MAY-23
21654|Dhunganda Formation|Reserved? Yes/No|Yes|16-MAY-23
21655|Dhupuwamirri Member|Name source|Dhupuwamirri Creek, a west-flowing fresh-water tributary of the Gulbuwangay River. The upper reaches of this creek cross-cut the member near AMG NF630900, at the northern tip of the Mitchell Range, Arnhem Bay 1:250 000 scale mapsheet area. Dhupuwamirri outstation (NF430995) lies to the south on Radalngarrmirri Creek.|16-MAY-23
21655|Dhupuwamirri Member|Unit history|Previously undifferentiated Fagan Volcanics. Equates roughly to the informal "members C and D" of Plumb and Roberts (1992).|16-MAY-23
21655|Dhupuwamirri Member|Geomorphic expression|Igneous units form recessive valleys adjacent to the more resistant ridges of the sedimentary units. Outcrop areas are typically highly vegetated.|16-MAY-23
21655|Dhupuwamirri Member|Type section locality|In Blue Mud Bay, outcrop in high-relief areas has been deeply incised by tributaries of the Koolatong River and many complete sections exist. Unfortunately, these are difficult to access without a helicopter. The type section follows the upper part of the river near latitude 13o30', longitude 135o30' between the lower boundary stratotype at NF550540 and the top boundary stratotype at NF540490. It comprises relatively abundant intrusive and hybrid rocks. Reference localities: Reference locality 1: A creek section at about NF580470 (Blue Mud Bay), which comprises a more diverse sedimentary-dominated succession than the type section. Reference locality 2: Easily accessible, but incomplete, outcrop adjacent to the Gove-Bulman road near NF600880 (Arnhem Bay) is representative of the local volcanic rocks.|16-MAY-23
21655|Dhupuwamirri Member|Extent|Outcrop occurs in two distinct areas in the northern and southern parts of the Mitchell Range, in both Arnhem Bay and Blue Mud Bay 1:250 000 scale mapsheet areas. The areas are separated by a considerable distance (~30 km).|16-MAY-23
21655|Dhupuwamirri Member|Thickness range|300-550 m|16-MAY-23
21655|Dhupuwamirri Member|Lithology|Sheet-like bodies of undeformed to mildly deformed porphyritic K-feldspar-quartz-albite rhyolite, locally associated with mafic igneous and hybrid rocks, and volcaniclastic and sedimentary rocks. Felsic igneous bodies are locally flow-banded and autoclastic and are sometimes associated with peripheral peperite breccia. Sedimentary units comprise white to maroon, fine- to medium-grained, thin- to thick-bedded, lithic sandstone, interbedded with massive to poorly-bedded, red-brown, micaceous and sandy mudstone. Sandstones are trough cross-bedded or rippled with locally common mudclasts. Bedded mudstones are rippled, wavy bedded, with shrinkage cracks and synsedimentary deformation structures. Volcaniclastic rocks include hyaloclastite and autoclastite breccia. All rock-types are locally sheared.|16-MAY-23
21655|Dhupuwamirri Member|Depositional environment|Sedimentary facies: shallow-water, low- to moderate-energy setting, perhaps fan-delta to fluvial. Igneous rocks: interpreted as flows and shallow sillts.|16-MAY-23
21655|Dhupuwamirri Member|Relationships and boundaries|Lies conformably between the sandstone-mudstone sequence of the Sheridan Member and the quartzose sandstones of the Parsons Range Group (Mattamurta Sandstone). A peperitic breccia is locally developed at the base of the lower felsic igneous unit of this member. In the southern part of the Mitchell Range, the upper contact is generally very sharp and is interpreted as a sequence (chronostratigraphic) boundary. The rock-type directly underlying the uniform medium-grained quartzose Mattamurta Sandstone varies considerably along strike, to include red-brown mudstone, lithic sandstone and igneous rocks. This variation is interpreted to be related to rapid lateral transitions in sedimentary facies, probably in response to emplacement of intrusive igneous bodies in the subsurface. Unfortunately, discontinuous outcrop does not allow this boundary to be traced into the northern part of the Mitchell Range where a similar type of boundary is not readily discernable. A lithostratigraphic boundary is mapped there, dividing igneous rock (Dhupuwamirri Member) from mudstone or sandstone (Mattamurta Sandstone). This boundary potentially occupies a marginally different chronostratigraphic position to the boundary in the south.|16-MAY-23
21655|Dhupuwamirri Member|Age reasons|Palaeoproterozoic (Statherian). Well constrained by single grain SHRIMP U-Pb geochronological techniques at ~1710 Ma (Rawlings and others, in prep.). The rhyolite porphyry sample used was collected from outcrop at NF544516.|16-MAY-23
21655|Dhupuwamirri Member|Correlations|Rawlings and others (in prep.) and Rawlings (1994) suggest correlation with the upper parts of the Tawallah and Katherine River Groups in the southern and western McArthur Basin respectively. More locally, it correlates to felsic igneous successions of the Spencer Creek Group in northeastern Arnhem Bay and tentatively with the Gadabara Volcanics in the eastern Blue Mud Bay mapsheet area. These correlations are based on geochemical, petrological, lithostratigraphic and geochronological constraints, and the physical form of igneous units.|16-MAY-23
21655|Dhupuwamirri Member|Proposed publication|Arnhem Bay-Gove 1:250 000 Geological Map Series, Northern Territory, National Geoscience Mapping Accord, Explanatory Notes (Rawlings and others, in prep.).|16-MAY-23
21655|Dhupuwamirri Member|Apprdate|16-MAR-1955|16-MAY-23
21655|Dhupuwamirri Member|Category|2|16-MAY-23
21655|Dhupuwamirri Member|Defn approved by|Brakel A.T./Haines P.W.|16-MAY-23
21655|Dhupuwamirri Member|Reserved? Yes/No|Yes|16-MAY-23
30418|Diamond Creek Volcanics|Name source|From Diamond Creek, in KATHERINE, which intersects the volcanic rocks around lat. 14o17?S, long. 133o04'E.|16-MAY-23
30418|Diamond Creek Volcanics|Unit history|The name Diamond Creek Member was introduced without formal definition by Ruker (1959) to describe a sequence of dolostone, sandstone, conglomerate and basic volcanics in WATERHOUSE - one of three members in the Kombolgie Formation. Randal (1963) introduced the Diljin Hill Formation to encompass the sequence overlying the Kombolgie Formation, and included the Diamond Creek Member in the Diljin Hill Formation. Walpole and others (1968) abandoned the Diljin Hill Formation and raised all three members within it to formation status. The oldest of these, the Diamond Creek Formation, was equated with the Cottee Formation, Shadforth Sandstone and McCaw Formation of Roberts & Plumb (1965) in MOUNT MARUMBA. Furthermore, it consists of two distinct units: a lower unit of dolostone, sandstone, conglomerate and probable fine-grained siliciclastic rocks directly comparable to the McCaw Formation, and an upper unit of vesicular basic lavas and associated pyroclastic rocks. The lower unit is here mapped as McCaw Formation, and the upper unit formally defined as Diamond Creek Volcanics. This is a more restricted use of the term than Ruker?s (1959) original conception.|16-MAY-23
30418|Diamond Creek Volcanics|Geomorphic expression|Recessive; poorly exposed, in valleys.|16-MAY-23
30418|Diamond Creek Volcanics|Type section locality|Adjacent to West Branch (Creek); base at lat. 14o11.4'S, long. 133o10.6'E (GR LE039304), top about 1 km southeast at lat. 14o11.5'S, long. 133o11.1'E (GR LE044299). The outcrop belt extending northeastward for 5 km from the type section contains the best exposures of the unit and is a reference area.|16-MAY-23
30418|Diamond Creek Volcanics|Extent|Waterhouse Syncline in northeastern KATHERINE and in adjacent parts of URAPUNGA.|16-MAY-23
30418|Diamond Creek Volcanics|Thickness range|230 m in type section; 100 m near Waterhouse Falls (lat. 14o27.5'S, long. 133o8'E); absent in southwestern WATERHOUSE 1:100 000 sheet area.|16-MAY-23
30418|Diamond Creek Volcanics|Lithology|Vesicular and amygdaloidal basic lavas (some autobrecciated) dominate. Tuff, fine- to coarse-grained volcaniclastic sandstone and coarse-grained lithic sandstone form minor intercalations. The lava, tuff and/or volcaniclastic sandstone locally also occur in breccia. The rocks are pervasively altered and weathered, and due to the relatively high contents of hematite (and limonite), colours range mostly between brick red, brown-red, red-brown and brown-grey. Original composition of the volcanic rocks is thought to range from andesite to basalt.|16-MAY-23
30418|Diamond Creek Volcanics|Depositional environment|Terrestrial to subaqueous environments.|16-MAY-23
30418|Diamond Creek Volcanics|Relationships and boundaries|Base of formation is at base of lowest volcanic rock (generally vesicular lava) above conglomerate and sandstone of the McCaw Formation. Outcrop is poor, the contact is rarely exposed, and the boundary is therefore generally drawn from aerial photographs, corresponding to a change to a more uniform, darker photopattern and colour. The contact is concordant and probably conformable. The top of the formation is at change from basic volcanics to sandstone of the Gundi Sandstone. The contact is sharp and probably unconformable, and the Gundi Sandstone locally rests directly on Kombolgie Formation.|16-MAY-23
30418|Diamond Creek Volcanics|Age reasons|Statherian Period of Palaeoproterozoic. The age is constrained only by the 1830 Ma age for parts of the underlying Edith River Group, and by the 1710 Ma age for the overlying West Branch Volcanics. The actual age is likely to be much closer to that of the West Branch Volcanics, as Diamond Creek volcanism appears to be an early phase of the activity which culminated in extrusion of the West Branch Volcanics.|16-MAY-23
30418|Diamond Creek Volcanics|Correlations|Upper Tawallah Group in central McArthur Basin, in part, particularly the Settlement Creek/Gold Creek Volcanics.|16-MAY-23
30418|Diamond Creek Volcanics|References|RANDAL, M.A., 1963 - KATHERINE, NT, 1:250 000 geological series. Bureau of Mineral Resources, Explanatory Notes, SD53-9. **RUKER, R., 1959 - The geology of the Diljin Hill, Black Cap, Waterhouse West and Canopy Rock West areas, Northern Territory. Bureau of Mineral Resources, Australia, Record 1959/67. **ROBERTS, H.G., & PLUMB, K.A., 1965 - MOUNT MARUMBA, NT, 1:250 000 geological series. Bureau of Mineral Resources, Explanatory Notes, SD53-6. **WALPOLE, B.P., CROHN, P.W., DUNN, P.R., & RANDAL, M.A., 1968 - Geology of the Katherine-Darwin Region, Northern Territory. Bureau of Mineral Resources, Australia, Bulletin 82, 304 pp.|16-MAY-23
80615|Dinkum Orthogneiss|Name source|Dinkum mica mine in JINKA 1:100 000 mapsheet, Northern Territory (135.5601degreesE 22.809degreesS (GDA 2020)).|16-MAY-23
80615|Dinkum Orthogneiss|Unit history|Reserved as Dinkum Gneiss in 2017.|16-MAY-23
80615|Dinkum Orthogneiss|Geomorphic expression|Poorly exposed; rises, rare hills, local fresh boulder fields. Strongly weathered, friable, disaggregated.|16-MAY-23
80615|Dinkum Orthogneiss|Type section locality|Eastern Mopunga Range at 135.6031degreesE 22.7224degreesS (GDA2020) in JINKA. Access via public roads and private tracks. Some off-track driving/walking might be required.|16-MAY-23
80615|Dinkum Orthogneiss|Description at type locality|Fresh boulder and blocky outcrop of migmatitic orthogneiss. Migmatitic layering with alternating cm-scale melanocratic bands including ~5 vol% biotite, leucocratic quartz-feldspar bands without biotite, and 1-10 cm wide cross-cutting bands of medium-grained K-feldspar-plagioclase-quartz veins interpreted as Marshall Granite.|16-MAY-23
80615|Dinkum Orthogneiss|Extent|Central-western HUCKITTA around the Mopunga Range (~135.2918-135.6524degreesE and ~22.5794-22.7319degreesS (GDA2020)).|16-MAY-23
80615|Dinkum Orthogneiss|General description|Commonly friable or disaggregated and strongly weathered outcrop with leached white feldspars, and an orange or pink weathered surface. Typically includes salmon pink K-feldspar, white or light coloured plagioclase, and grey quartz; rare accessory, mm- or sub-mm biotite. Commonly weakly to moderately gneissic and migmatitic (which may be obscured by strong weathering); locally mylonitic. Geochemical composition is monzogranite.|16-MAY-23
80615|Dinkum Orthogneiss|Lithology|Fresh boulder and blocky outcrop of migmatitic orthogneiss. Migmatitic layering with alternating cm-scale melanocratic bands including ~5 vol% biotite, leucocratic quartz-feldspar bands without biotite, and 1-10 cm wide cross-cutting bands of medium-grained K-feldspar-plagioclase-quartz veins interpreted as Marshall Granite.|16-MAY-23
80615|Dinkum Orthogneiss|Depositional environment|Genesis: Continental margin environment, either arc cordillera or back arc basin, or derived from melting of pre-existing crust that formed in a continental margin environment.|16-MAY-23
80615|Dinkum Orthogneiss|Relationships and boundaries|Leucosomes are interpreted to have pooled and formed the Marshall Granite during migmatitisation of the Dinkum Orthogneiss.|16-MAY-23
80615|Dinkum Orthogneiss|Identifying features|The only migmatitic orthogneiss north of the Delny Shear Zone in HUCKITTA 1:250 000 mapsheet (Weisheit et al in prep).|16-MAY-23
80615|Dinkum Orthogneiss|Structure and Metamorphism|Migmatitic to locally compositionally layered, gneissic. Intruded prior to regional granulite- to amphibolite-facies high-thermal-gradient metamorphism.|16-MAY-23
80615|Dinkum Orthogneiss|Age reasons|Crystallisation of the igneous protolith at 1793 +/- 4 Ma (LA-ICP-MS 207Pb/206Pb zircon age; Beyer et al 2022).|16-MAY-23
80615|Dinkum Orthogneiss|Correlations|Interpreted as co-magmatic and co-genetic with constituent units of the Molyhil, Fosters and Casper suites, Baikal Supersuite, based on similar geochemical and isotopic composition, and timing of structural fabric development.|16-MAY-23
80615|Dinkum Orthogneiss|Alteration and Mineralisation|Locally K-feldspar-quartz altered, chloritised and silicified; locally brecciated and intruded by quartz-veins. No known mineralisation.|16-MAY-23
80615|Dinkum Orthogneiss|Geophysical Expression|Commonly associated with magnetic high responses; no characteristic gravity response; radiometric high response.|16-MAY-23
80615|Dinkum Orthogneiss|Geochemistry|Metaluminous to weakly peraluminous I-type monzogranite. High LREE enrichment compared to MREE, and well developed negative Eu anomalies.|16-MAY-23
80615|Dinkum Orthogneiss|Defn author|Anett Weisheit, Barry Reno, Eloise Beyer, Pablo Farias (NT Department of Primary Industry and Resources, Northern Territory Geological Survey) 3-MAY-2022.|16-MAY-23
80615|Dinkum Orthogneiss|References|Beyer EE, Whelan JA, Reno BL, Weisheit A, Thompson J, Meffre S, Huang H, and Woodhead JD, 2022 Summary of results. NTGS laser ablation ICP-MS U-Pb-Hf geochronology project: selected samples from HUCKITTA 1:250 000 mapsheet, May 2011-October 2018. Northern Territory Geological Survey, Darwin, Record 2022-007.  **Weisheit A et al, in prep. Huckitta, Northern Territory. 1:250 000 geological map series explanatory notes, SF53-11. Northern Territory Geological Survey, Darwin.|16-MAY-23
24608|Dirty Water Metamorphics|Name source|Dirty Water Billabong (GM 678236) ;on the Koolpinyah 1:100 000 Sheet.|16-MAY-23
24608|Dirty Water Metamorphics|Unit history|Referred to as the Fish Creek Schists (informal) by R J Perring and L J Farra 1980 - EL1642 - Woolner, second annual report, Geopeko Limited. Northern Territory Department of Mines and Energy, Company Report 81/30 (unpublished). I S Williams and W Compston, 1983 - Ion microprobe U-Pb dating of zircons from granitoids recovered in core drill holes P4-10, P11-1, P12-11 and P14-1, Woolner, Northern Territory. In Mobil Energy Minerals Australia, 1983 - Annual report for EL3478 Woolner. Northern Territory Department of Mines and Energy, Company Report 83/231 (unpublished).|16-MAY-23
24608|Dirty Water Metamorphics|Type section locality|An approximately 800 m thick sequence of schist and gneiss as intersected in the following drill holes which form a composite section at the depths indicated; DDH P1-S1 (56-296 m), DDH P1-S2 (71-156 m), DH P1-6 (45-68 m) and DH P1-2 (46-48 m), drilled by Geopeko Limited. Type lithologies are presented by core from DDH P1-S1 and DDH P1-S2. The location of the drill holes is abetween co-ordinates GM604337 and GM613337. Core is stored at the Northern Territory Department of Mines and Energy Core Library, Darwin.|16-MAY-23
24608|Dirty Water Metamorphics|Extent|In the northeastern part of the Koolpinyah sheet area (sheet 5173) the unit is non-outcropping and concealed by 50 m to 70 m of Mesozoic and Cainozoic sediments.|16-MAY-23
24608|Dirty Water Metamorphics|Thickness range|Approximately 800 m. Lower Unit +500 m; Upper Unit .270 m.|16-MAY-23
24608|Dirty Water Metamorphics|Lithology|Lower Unit: (Apd1): Quartz feldspar-biotite gneiss; quartz-feldspar-mica gneiss; subordinate meta-arkose, hornblende-biotite schist and quartzite.  Upper Unit: (APd2): Chlorite-quartz-calcite schist; graphitic mica-quartz-calcite schist; subordinate magnetite-chlorite-quartz+/-calcite schist, hornblende-biotite schist, quartz-chlorite schist, banded magnetite pyrite metaquartzite, dolomite, quartzite.|16-MAY-23
24608|Dirty Water Metamorphics|Relationships and boundaries|Lower unit unconformably overlies the Woolner Granite. Upper unit is conformable and transitional with lower unit. Both are unconformably overlain by the Mount Partridge Group.|16-MAY-23
24608|Dirty Water Metamorphics|Age reasons|Archaean to Early Proterozoic. Reasons: 1) The Woolner Granite is Archaean (a date of 2675 +/- 14 m.y.) was determined using U/Pb isotopic ratios in zircon by Williams and Compston 1983); 2) The Mount Partridge Group is part of the Early Proterozoic sediments of the Pine Creek Geosyncline.|16-MAY-23
24608|Dirty Water Metamorphics|Proposed publication|Koolpinyah Explanatory Notes (Northern Territory Geological Survey)|16-MAY-23
24248|Don Creek Sandstone|Name source|From Don Creek, which drains part of the eastern Carrara 1:100 000 Sheet area (Sheet 6460), Northern Territory.|16-MAY-23
24248|Don Creek Sandstone|Unit history|Formerly an unnamed sandstone member within the Carrara Range Formation (now Group) of Smith & Roberts (1963).|16-MAY-23
24248|Don Creek Sandstone|Type section locality|South of the Carrara Range. The base is at grid ref. 833292, and the top is at grid ref. 835301. It consists of 420 m of pebbly quartz sandstone.|16-MAY-23
24248|Don Creek Sandstone|Extent|Scattered outcrops along the southern margin of the Carrara Range, in Carrara; total outcrop of about 10 km2.|16-MAY-23
24248|Don Creek Sandstone|Lithology|Massive, medium to coarse sandstone with scattered quartz granules and pebbles. Cross-bedded, irregularly silicified.|16-MAY-23
24248|Don Creek Sandstone|Relationships and boundaries|Basal formation of the Carrara Range Group. Overlies Murphy Metamorphics, probably  with angular unconformity - contact is a distinct metamorphic and structural discontinuity. Overlain conformably by Mitchiebo Volcanics - boundary is marked by abrupt lithological change, from sandstone to basalt or trachyte.|16-MAY-23
24248|Don Creek Sandstone|Age reasons|Proterozoic, Carpentarian - correlated with sequences of known Carpentarian age by Plumb & Derrick (1975) and Hutton & Sweet (1982, in press).|16-MAY-23
24248|Don Creek Sandstone|Defn approved by|Brakel A.T. (subject to Hutton & Sweet reference details being entered when available)|16-MAY-23
24248|Don Creek Sandstone|Defn Reference|83/23538|16-MAY-23
21680|Donydji Group|Name source|Donydji outstation (AMG NF510748), Arnhem Bay 1:250 000 scale map sheet area.|16-MAY-23
21680|Donydji Group|Unit history|The formations which now collectively make up the Donydji Group were informally referred to by Crohn (1956) as the "Mitchell Range" and "Cypress Creek Formations". This package of stratigraphy was later revised by Dunnet (1965) to include two new subdivisions, the "Ritarango beds" and Fagan Volcanics. These were subsequently formalised by Plumb and Roberts (1992).|16-MAY-23
21680|Donydji Group|Constituents|In ascending order; Dhunganda Formation, Ritarango Formation and Fagan Volcanics. Dhunganda Formation (new name) and Ritarango Formation (revised name) are new subdivisions of the "Ritarango beds" of Plumb and Roberts (1965). Fagan Volcanics were named by Dunet (1965) and formalised by Plumb and Roberts (1992).|16-MAY-23
21680|Donydji Group|Geomorphic expression|Sandstone-dominated formations form resistant and upstanding ridges, while the igneous-mudstone-volcaniclastic association is typically recessive.|16-MAY-23
21680|Donydji Group|Type section locality|Type localities and reference areas as defined for each constituent formation.|16-MAY-23
21680|Donydji Group|Extent|Small area bordering on southern Arnhem Bay and northern Blue Mud Bay 1:250 000 scale map sheet areas; comprises almost the entire Mitchell Range.|16-MAY-23
21680|Donydji Group|Thickness range|2000-3000 m|16-MAY-23
21680|Donydji Group|Lithology|Strongly to mildly deformed lithic to quartzose sandstone and conglomeratic sandstone, felsic and mafic igneous rocks, volcaniclastic rocks, and mudstone.|16-MAY-23
21680|Donydji Group|Depositional environment|Ranges from fluviatile to shallow- and moderate-depth water for the sedimentary facies; igneous rocks are volcanic and intrusive.|16-MAY-23
21680|Donydji Group|Relationships and boundaries|Probably unconformably overlies the metamorphic and granitic rocks of the Mirarrmina Complex and is in turn conformably overlain by the arenaceous rocks of the Parsons Range Group.|16-MAY-23
21680|Donydji Group|Age reasons|Palaeoproterozoic (Statherian). The maximum age is poorly constrained by an inferred age of ~1870 Ma for the underlying Mirarrmina Complex (based on correlation with Bradshaw Complex in eastern Arnhem Bay/western Gove mapsheet areas; Plumb and Roberts, 1992). Most likely correlation of the basal part of the sequence according to Rawlings (1994) is with the lower Tawallah Group (see correlatives), suggesting the maximum age is ~1800 Ma or slightly younger. The minimum age of the Donydji Group is well constrained by ~1710 Ma ages for concordant igneous units at the top of the group (Maidjunga and Dhupuwamirri Members of the Fagan Volcanics; Rawlings and others, in prep.).|16-MAY-23
21680|Donydji Group|Correlations|Rawlings (1994) first attempted regional correlation of the Donydji Group based on geochemical, petrological, lithostratigraphic and geochronological constraints, and the physical form of igneous units. The Donydji Group as an entity equates stratigraphically to parts of the Tawallah and Katherine River Groups in the southern and western parts of the McArthur Basin respectively. The upper part (Fagan Volcanics) correlates with the Spencer Creek Group in northwestern Gove 1:250 000 mapsheet area and tentatively with the Gadabara Volcanics in eastern Blue Mud Bay. Conversely, the lower part (Dhunganda Formation) may well correlate with the upper Groote Eylandt Group, depending on the difference in age between the Dhunganda and Ritarango Formations and Fagan Volcanics.|16-MAY-23
21680|Donydji Group|Proposed publication|Arnhem Bay-Gove 1:250 000 Geological Map Series, Northern Territory, National Geoscience Mapping Accord, Explanatory Notes (Rawlings and others, in prep.).|16-MAY-23
21680|Donydji Group|Comments|The Donydji Group is readily distinguishable from the Mirarrmina Complex below and Parsons Range Group above. It has a distinctive association of igneous and sedimentary rocks and structural characteristics which enables it to be differentiated as an entity. Similarly, there is enough internal variation to warrant subdivision into the component formations. The lower two formations are apparently divided by a significant structural and sedimentological break, but are contiguous with the overall tectonic evolutionary trend. This break is thought to have local significance but is subtle in a regional sense.|16-MAY-23
21680|Donydji Group|Category|2|16-MAY-23
21680|Donydji Group|Defn approved by|Brakel A.T./Haines P.W.|16-MAY-23
21680|Donydji Group|Proposer|Rawlings D.J.|16-MAY-23
21680|Donydji Group|Reserved? Yes/No|Yes|16-MAY-23
21695|Drimmie Head Granite|Name source|Drimmie Head on Drimmie Peninsula, Gove Harbour (AMG PG849473, Arnhem Bay-Gove).|16-MAY-23
21695|Drimmie Head Granite|Unit history|Outcrop now mapped as this unit was previously mapped as the 'Bradshaw Granite' by Dunnet (1965) and the 'Drimmie Head type' of the Bradshaw Complex by Plumb abd Roberts (1992), Madigan and Rawlings (1994) and Madigan and others (1995).|16-MAY-23
21695|Drimmie Head Granite|Geomorphic expression|The main outcrop occurs as small islands, bare pavements, tors and boulders, surrounded by low scrub.|16-MAY-23
21695|Drimmie Head Granite|Type section locality|Outcrop between Drimmie Head and McIntyre Point, centred on lat. 12degrees 13' 30"s, long.136degrees 42' 30"E (AMG PG846477).|16-MAY-23
21695|Drimmie Head Granite|Extent|Eastern and western sides of Melville Bay, northeastern Arnhem Bay-Gove.|16-MAY-23
21695|Drimmie Head Granite|Lithology|Garnetiferous leucogranite and granitic gneiss with abundant enclaves of metasedimentary and mafic rocks. Leucogranite, which dominates this unit, is medium-to coarse-grained and contains quartz, garnet, plagioclase, cordierite and K-feldspar. It has consertal granular texture with some recrystallised boundaries. Porphyritic pink and red garnet is up to 5cm across, severely fractured in part and has inclusions of quartz, biotite, magnetite, zircon and muscovite. Metasedimentary and mafic enclaves (up to 4 m long) include psammitic and pelitic gneiss, calcsilicate hornfels and mafic granulite.|16-MAY-23
21695|Drimmie Head Granite|Relationships and boundaries|Part of the Bradshaw Complex. It intrudes the Melville Bay Metamorphics of the Bradshaw Complex and is thought to be derived by partial melting from them. It is overlain by Cretaceous sediments, Cainozoic laterite and Quaternary coastal alluvium.|16-MAY-23
21695|Drimmie Head Granite|Age reasons|The age of this unit, which is generally taken as the peak metamorphic age of the Bradshaw Complex, is 1867+/-12 Ma (Page, pers. comm. 1995). This age was determined from analysis of single zircon granis by SHRIMP U-Pb geochronological techniques, utilising a sample of garnetiferous granite collected from AMG PG903516.|16-MAY-23
21695|Drimmie Head Granite|Correlations|The Drimmie Head Granite is a syn-metamorphic leucogranite suite hich was probably derived from the inhomogeneous melting of a metasedimentary protolith. Gneissic enclaves within the Drimmie Head Granite resemble the Melville Bay Metamorphics. Broad correlation with the Nimbuwah Complex and high-grade metamorphic portions of the Pine Creek succession.|16-MAY-23
21695|Drimmie Head Granite|Defn author|T. L. Madigan and D.J. Rawlings, 1997.|16-MAY-23
38037|Drummond Formation|Name source|From Mount Drummond, a prominent hill at the southern margin of the Carrara Range, at latitude 18o42'S longitude 137o36'E (within MOUNT DRUMMOND).|16-MAY-23
38037|Drummond Formation|Name source|Mount Drummond is a prominent hill at southern margin of Carrara Range (GDA94 latitude 18°42'S, longitude 137°36'E) in the Northern Territory, which hosts siliciclastic sediments of the Drummond Formation.|
38037|Drummond Formation|Unit history|Previously identified as undivided sandstone within Carrara Range Formation and Bluff Range beds (both superseded) by Smith and Roberts (1963) in the First Edition MOUNT DRUMMOND 1:250 000 mapsheet; the unit was also incorrectly mapped in places by Smith and Roberts (1963) as the Constance Sandstone; subsequently mapped by Sweet (1984) as part of the now superseded lower Musselbrook Formation (units LPmb1b to LPmb1f) in the CARRARA RANGE REGION First Edition 1:100 000 mapsheet; subsequently mapped by Rawlings et al (2006, 2008) who identified the sandstone as the Drummond Formation of the McNamara Group in the Second Edition MOUNT DRUMMOND 1:250 000 mapsheet.|
38037|Drummond Formation|Unit history|Mapped as undifferentiated sandstone within the 'Carrara Range Formation' and 'Bluff Range beds' (both superseded) by Smith and Roberts (1963) on the first edition MOUNT DRUMMOND sheet; mismapped as Constance Sandstone in places on that map; subsequently mapped as part of the now superseded lower Musselbrook Formation (units Pmb1b to Pmb1f on the first edition Carrara Range Region 1:100 000 sheet; Sweet 1984).|16-MAY-23
38037|Drummond Formation|Constituents|Informal units (Pcr1, Pcr2, Pcr3, Pcr4). Although informal members are recognisable in many outcrops, faulting and variable quality of outcrop preclude formal recognition.|
38037|Drummond Formation|Constituents|Four informal members recognised in the type area; identified from oldest to youngest as Pmd1 to Pmd4.|16-MAY-23
38037|Drummond Formation|Geomorphic expression|Forms many of the higher ridges and intervening valleys throughout Carrara Range; low hills in northern outcrops.|
38037|Drummond Formation|Geomorphic expression|Forms many of the higher ridges and intervening valleys throughout the Carrara Range; low hills in northern outcrops.|16-MAY-23
38037|Drummond Formation|Type section locality|Across a series of strike ridges in the Carrara Range in the MOUNT DRUMMOND 1:250 000 mapsheet, from south to north: base at (GDA94) 18°37.3'S, 137°28.0'E (Z53S 760262mE 7939244mN); top at (GDA94) 18°36.8'S, 137°28.0'E (Z53S 760275mE 7940166mN).|
38037|Drummond Formation|Type section locality|Across a series of strike ridges in the northwestern Carrara Range, from south to north: base at 18o37.3'S, 137o28.0'E (760262E 7939244N); top is at 18o36.8'S, 137o28.0'E (760275E 7940166N).|16-MAY-23
38037|Drummond Formation|Extent|Carrara Range, in southeastern MOUNT DRUMMOND, and to the north around Soak Creek and the headwaters of South Nicholson Creek.|16-MAY-23
38037|Drummond Formation|Extent|The Drummond Formation outcrops in the MOUNT DRUMMOND 1:250 000 mapsheet, in the Carrara Range, and to north around Soak Creek and headwaters of South Nicholson Creek.|
38037|Drummond Formation|Thickness range|460 m in the type section. It thickens to ~600 m to the west, and thins to 300 m to the east in the central Carrara Range. It is a minimum of 400 m thick 20 km north of the type section, in the Maloney Creek Inlier (Rawlings et al, in prep). Thickness ranges: Pmd1: 100 m; Pmd2: 50-200 m; Pmd3: 100-150 m; Pmd4: 40-200 m.|16-MAY-23
38037|Drummond Formation|Thickness range|460 m thick in type section. Thickens to 600 m thick to the west and thins to 300 m thick to the east in central Carrara Range. Minimum 400 m thick, 20 km north of type section, in Maloney Creek Inlier. Thickness ranges: Pcr1 = 100 m thick; Pcr2 = 50–200 m thick; Pcr3 = 100–150 m thick; Pcr4 = 40–200 m thick.|
38037|Drummond Formation|Lithology|Four informal unnamed members, from base to top Pcr1 to Pcr4. Pcr1: Thin polymictic conglomerate overlain by thin- to medium-bedded, fine-grained lithic sandstone, laminated siltstone, red beds of brown lithic dolomitic sandstone and silicified dolostone; cauliflower chert; dark grey medium-bedded pyritic coarse sandstone. Pcr2: White to brown, medium- to thick-bedded, fine- to medium-grained sublithic to quartzose sandstone; minor grey chert. Pcr3: Laminated kaolinised and silicified claystones (altered carbonate rocks?), fine ferruginous sandstone, siltstone, and stromatolitic chert; fine, sublithic siltstone and sandstone. Pcr4: White, medium- to thick-bedded, fine- to medium-grained sublithic to quartzose sandstone, with scattered coarse laminae and granules.|
38037|Drummond Formation|Lithology|Four readily mapped members, from base to top Pmd1 to Pmd4.  Pmd1: Thin polymictic conglomerate overlain by thin to medium bedded, fine-grained lithic sandstone, laminated siltstone, red beds of brown lithic dolomitic sandstone and chertified dolostone; cauliflower chert; dark grey medium bedded pyritic coarse sandstone.  Pmd2: White to brown, medium to thick bedded, fine to medium sublithic to quartzose sandstone; minor grey chert.  Pmd3: Laminated kaolinised and chertified claystones (altered carbonates?), fine ferruginous sandstone, siltstone, and stromatolitic chert; fine, sublithic siltstone and sandstone.  Pmd4: White, medium to thick bedded, fine to medium sublithic to quartzose sandstone with scattered coarse laminae and granules.|16-MAY-23
38037|Drummond Formation|Depositional environment|Shallow marine and fluvial; red beds and carbonates may be sabkha environments.|16-MAY-23
38037|Drummond Formation|Relationships and boundaries|Sharp lower contact, marked in places by conglomerate and angular discordance, and therefore unconformable on the Boomerang Formation (previously Surprise Creek Formation). Gradational conformable to unconformable contact with the overlying Brumby Formation. Overlain unconformably by the Bullrush Conglomerate in Maloney Creek Inlier.|
38037|Drummond Formation|Relationships and boundaries|Sharp lower contact, marked in places by conglomerate and angular discordance, and therefore unconformable on Surprise Creek Formation; gradational conformable contact with the overlying Brumby Formation. Overlain unconformably by the Bullrush Conglomerate in the Maloney Creek Inlier (Rawlings et al, in prep). Parent unit: Part of McNamara Group.|16-MAY-23
38037|Drummond Formation|Identifying features|Abundant ripples. Basal, matrix-supported conglomerate present in Pcr1. Pcr3 contains massive, stromatolitic chert (Rawlings et al, 2008).|
38037|Drummond Formation|Age reasons|Maximum age constrained by Top Rocky Rhyolite, dated at 1725+/-3 Ma (Page et al 2000); younger limit established by correlation with McNamara Group in LAWN HILL to the east - eg, ages of 1658-1653 Ma for the Paradise Creek Formation (Page et al 2000). The Drummond Formation is likely to be very close to this age.|16-MAY-23
38037|Drummond Formation|Age reasons|Maximum depositional ages derived from U-Pb SHRIMP dating of detrital zircons (Kositcin and Carson 2019): 1715 ± 30 Ma (GA sample number 2785617). 1792 ± 13 Ma (GA sample number 2786178).|
38037|Drummond Formation|Correlations|Detrital zircon spectra for samples of Drummond Formation (GA samples 2785617, 2786178; Kositcin and Carson 2019) are comparable to GA sample 2785622 of the Gator Sandstone of the Carrara Range Group, suggesting that the Drummond Formation should be reattributed from the McNamara Group to the Carrara Range Group.|
38037|Drummond Formation|Correlations|Equates to the upper Gunpowder Creek and lower Paradise Creek Formations in the Lawn Hill region, ie the Gun Supersequence (Rawlings et al, in prep).|16-MAY-23
38037|Drummond Formation|Alteration and Mineralisation|Mildly silicified.|
38037|Drummond Formation|Geophysical Expression|Moderate to high magnetic response, possibly as a consequence of its stratigraphic proximity to highly magnetic volcanic units.|
38037|Drummond Formation|Geochemistry|Geochemical datasets from Boomerang Formation are published in Carson et al (2020).|
38037|Drummond Formation|Defn author|Rawlings et al (2005).|05-OCT-23
38037|Drummond Formation|Defn author|Jack Simmons, Ben Williams, Chris Carson, Charles Verdel (Northern Territory Geological Survey). 09-OCT-2020. Drummond Formation first defined by Rawlings et al (2008).|
38037|Drummond Formation|Comments|Note: Standard series 1:100 000 and 1:250 000 sheet names are shown in upper case.|
38037|Drummond Formation|Comments|Although the informal members are recognisable in many outcrops, their thinness, faulting and variable quality of outcrop preclude formal recognition of them. Note: All locations are based on the GDA94 geodetic datum. Standard series 1:250 000 sheet names are shown in upper case.|16-MAY-23
38037|Drummond Formation|References|Carson CJ, Jarrett AJM, Anderson JR, Champion DC and Henson PA, 2020. Exploring for the Future – Whole rock geochemistry data release of sedimentary and igneous rocks from the South Nicholson region, Northern Territory and Queensland Geoscience Australia, Record 2020/02.   **Carson, C. J., Kositcin, N., Anderson, J. R., and Henson, P. A. in prep. A revised Proterozoic tectono-stratigraphy of the South Nicholson region, Northern Territory, Australia - insights from SHRIMP U-Pb detrital zircon geochronology. Australian Journal of Earth Sciences.   **Kositcin N and Carson CJ, 2019. New SHRIMP U-Pb zircon ages from the South Nicholson and Carrara Range regions, Northern Territory. Geoscience Australia, Record 2019/09.  **Page RW, Jackson MJ and Krassay AA, 2000. Constraining sequence stratigraphy in north Australian basins: SHRIMP U–Pb zircon geochronology between Mt Isa and McArthur River. Australian Journal of Earth Sciences 47(3), 431-459.  **Rawlings DJ, Sweet IP and Kruse PD, 2006. Mount Drummond, NT (Second Edition). 1:250 000 Geological Map, Sheet SE 53-12. Northern Territory Geological Survey, Darwin.  **Rawlings DJ, Sweet IP and Kruse PD, 2008. Mount Drummond, NT (Second Edition). 1:250 000 Geological Map Series Explanatory Notes, Sheet SE 53-12. Northern Territory Geological Survey, Darwin.  **Sweet IP, 1984. Carrara Range region, Northern Territory (First Edition). 1:100 000 geological map commentary, portions of 6360 and 6460. Bureau of Mineral Resources, Canberra.  **Sweet IP, Mond A and Stirzaker J, 1984. Carrara Range Region, Northern Territory. 1:100 000 Geological Map Series, Carrara 6460 and Mitchiebo 6360. Bureau of Mineral Resources (BMR).|
38037|Drummond Formation|References|**PAGE R.W., Jackson M.J. and Krassay A.A., 2000. Constraining sequence stratigraphy in north Australian basins: SHRIMP U-Pb zircon geochronology between Mt Isa and McArthur River. Australian Journal of Earth Sciences, 47, 3; 431-459.  **RAWLINGS D.J. Sweet I.P. and Kruse P.D., in prep [2008]. Mount Drummond, Northern Territory (Second Edition); 1:250 000 Geological Map Series, sheet SE53-12. Northern Territory Geological Survey, Map and Explanatory Notes.  **SMITH J.W. and Roberts H.G., 1963. Mount Drummond, N.T. (First Edition); 1:250,000 geological series, sheet SE53-12. Bureau of Mineral Resources, Geology and Geophysics, Map and Explanatory Notes.  **SWEET I.P., 1984. Carrara Range region, Northern Territory (First Edition); 1:100,000 geological series, portions of sheets 6460 and 6360. Bureau of Mineral Resources, Geology and Geophysics, Explanatory Notes.|05-OCT-23
83011|Duckling Granodiorite|Name source|Due to the lack of suitable nearby geographic names, we have named this unit following a theme of juvenile animals, given this unit?s parent unit, the Mount Lamb Suite.|16-MAY-23
83011|Duckling Granodiorite|Geomorphic expression|No known outcrops.|16-MAY-23
83011|Duckling Granodiorite|Type section locality|Drill hole NDIBK01, down-hole depth from 221.15 m to 223.64 m. Drillhole location 618060mE 7835505mN (MGA94 zone 53) / 19.571878S 136.125556E. Drill core is stored at the NTGS core library in Alice Springs.|16-MAY-23
83011|Duckling Granodiorite|Description at type locality|Pink-grey, medium- to coarse-grained granodiorite. Primary igneous minerals include plagioclase, potassium feldspar, quartz and accessory apatite, zircon and rutile.|16-MAY-23
83011|Duckling Granodiorite|Extent|This unit is interpreted as an elongate, homogeneously non-magnetic body, approximately 40 km long, in the vicinity of drillhole NDIBK01 (Clark et al, 2021).|16-MAY-23
83011|Duckling Granodiorite|General description|Only known in the type interval. See description above.|16-MAY-23
83011|Duckling Granodiorite|Thickness range|Approximately 2.5 m in nominated type section in drill hole NDIBK01. Several other intersections of this unit occur in drill core NDIBK01. These intersections are approximately one to three metres in length.|16-MAY-23
83011|Duckling Granodiorite|Lithology|Medium- to coarse-grained granodiorite. Primary igneous minerals include plagioclase, potassium feldspar, quartz and accessory apatite, zircon and rutile.|16-MAY-23
83011|Duckling Granodiorite|Relationships and boundaries|The unit intrudes foliated and metamorphosed rocks of the Alroy Formation. The lower boundary is broadly conformable to foliation in the Alroy Formation, whereas the upper boundary appears to cross-cut the same foliation. It is possible that the emplacement of this intrusive unit postdated the formation of the dominant foliation in the surrounding Alroy Formation.|16-MAY-23
83011|Duckling Granodiorite|Identifying features|Felsic composition and homogenous, medium-grained texture. The age of this unit is a key characteristic (see below).|16-MAY-23
83011|Duckling Granodiorite|Structure and Metamorphism|In thin-sections of the limited drill core available, this unit appears largely undeformed, with the exception of minor faulting and related vein formation. The unit has been affected by minor low-grade retrograde metamorphism, with chlorite and muscovite replacing biotite and amphibole. However, the interpreted elongate body of this intrusive unit, and the presence of cross-cutting structures in geophysical data, imply that this unit predates significant ductile deformation (Clark et al., 2001).|16-MAY-23
83011|Duckling Granodiorite|Age reasons|SHRIMP U-Pb analysis of this rock indicates that it was emplaced at 1851.6 +/-7.5 Ma (Kositcin and Cross et al., in prep).|16-MAY-23
83011|Duckling Granodiorite|Geophysical Expression|Appears as magnetically bland and slightly denser than rocks of the Alroy Formation in regional geophysical imagery.|16-MAY-23
83011|Duckling Granodiorite|Geochemistry|Based on limited data, the Duckling Granodiorite has a restricted, felsic compositional range (SiO2 = 72.8-74.5 wt.%). Like other constituents of the Mount Lamb Suite, it is high-K (K2O > 5.48 wt.%), peraluminous (ASI = ~1.25) and enrichment of light rare earth elements relative to medium and heavy rare earth elements (normalised La/Yb = 13-17) with relatively flat medium to heavy rare earth elements (normalisedGd/Yb = 1.5-1.8), although it lacks a pronounced negative Eu anomaly (Eu/Eu* = 0.76-0.88). Evolved whole rock Nd isotopic composition from a single sample (epsilonNd ~1851.6 Ma = -2.89).|16-MAY-23
83011|Duckling Granodiorite|Defn author|A.D. Clark 24-MAR-2022.|16-MAY-23
83011|Duckling Granodiorite|Proposed publication|Schofield and Clark et al., (in prep). Geology of the East Tennant area, Northern Territory, journal publication.|16-MAY-23
83011|Duckling Granodiorite|Comments|Geochemical characteristics and presence of hornblende suggest an I-type affinity, although this is somewhat at odds with peraluminous bulk rock compositions.|16-MAY-23
83011|Duckling Granodiorite|References|Kositcin, N., Cross A.J., et al., in prep. Geochronology of the East Tennant area, Geoscience Australia record.  **Schofield and Clark et al., (in prep). Geology of the East Tennant area, Northern Territory.  **Clark, A., Highet, L., Schofield, A., Doublier, M., 2021. Solid Geology map of the East Tennant region, dataset, Geoscience Australia.|16-MAY-23
21715|Durabudboi beds|Name source|Durabudboi River, Arnhem Bay-Gove 1:250 000 scale map sheet area.|16-MAY-23
21715|Durabudboi beds|Unit history|None. Dunnet (1965) did not previously differentiate this unit from surrounding Cretaceous and Cainozoic deposits.|16-MAY-23
21715|Durabudboi beds|Geomorphic expression|Very low rises and dissected country beneath laterite break-aways.|16-MAY-23
21715|Durabudboi beds|Type section locality|Reference locality: Small roadside quarry, and low hill immediately behind, on the main Nhulunbuy road 25 km east of the Gapuwiyak turn-off (latitude 12o45'S, longitude 136o01'E; AMG PF102900).|16-MAY-23
21715|Durabudboi beds|Extent|Central Arnhem Bay-Gove 1:250 000 scale map sheet area, near headwaters of  Durabudboi River.|16-MAY-23
21715|Durabudboi beds|Thickness range|Unknown as no stratigraphic base or top is exposed. Individual outcrops only display a few metres of section.|16-MAY-23
21715|Durabudboi beds|Lithology|Weathered and ferruginised mudstone, which was probably originally dolomitic. On the surface it is commonly dark red due to the ferruginisation, but when exposed in creek beds may be purple, white or yellow. Bedding is thin and flaggy, and the rock is finely laminated. Minor chert is also present. At the reference locality the main lithology is finely laminated, yellowish, blocky mudstone, with the appearance of having originally been dolomitic. On the hill behind the quarry, rubble of leached and silicified carbonates include relic intraclastic, arenitic, stromatolitic and evaporitic fabrics.|16-MAY-23
21715|Durabudboi beds|Relationships and boundaries|No contacts with other units seen. Regional structural interpretations suggest that these beds lie beneath the Roper Group, but this cannot be confirmed with complete confidence.|16-MAY-23
21715|Durabudboi beds|Age reasons|Uncertain, but probably late Palaeoproterozoic or early Mesoproterozoic.|16-MAY-23
21715|Durabudboi beds|Correlations|There are a number of potential correlatives including fine grained units in the Balma, Habgood, and Nathen Groups and the Jalma Formation. Alternatively the beds may correlate with units within the Roper Group, but this is considered unlikely.|16-MAY-23
21715|Durabudboi beds|Proposed publication|Arnhem Bay-Gove 1:250 000 scale Geological Map Series, Northern Territory, National Geoscience Mapping Accord, Explanatory Notes, SD 53-3, 4 (Rawlings and others, in prep.).|16-MAY-23
21715|Durabudboi beds|Comments|The unit remains informal due to considerable uncertainties regarding its stratigraphic relationships and correlatives.|16-MAY-23
21715|Durabudboi beds|Category|2|16-MAY-23
21715|Durabudboi beds|Defn approved by|Brakel A.T./Haines P.W.|16-MAY-23
33173|Echo Sandstone|Name source|Echo Gorge, near Redbank Mine, northeast Calvert Hills 1:250 000 sheet area (17o10'S, 137o43'E or 789500E 8098000N).|16-MAY-23
33173|Echo Sandstone|Unit history|Previously mapped as 'Masterton Formation' by Roberts et al. (1963) and Yates (1965), then as Masterton Sandstone by Jackson et al (1987) and Ahmad & Wygralak (1989). This definition for the Echo Sandstone also includes proximal rhyolite talus conglomerate that was assigned by Ahmad & Wygralak (1989) to the Hobblechain Rhyolite.|16-MAY-23
33173|Echo Sandstone|Constituents|Pungalina Member (separate definition and type section).|16-MAY-23
33173|Echo Sandstone|Geomorphic expression|Generally resistant, forming large flat-lying or gently-dipping karstically-weathered plateaux and mesas.|16-MAY-23
33173|Echo Sandstone|Type section locality|Due to discontinuous outcrop, a composite type section is nominated near Redbank Mine at 17o10'S, 137o44'E (Calvert Hills sheet). The lower part of the type section, which includes the lower mudstone-conglomerate portion of the Echo Sandstone (the Pungalina Member), runs between 795120E 8099030N (17o10.05'S, 137o46.44'E), where it unconformably overlies Gold Creek Volcanics, to 794720E 8098900N (17o10.05'S, 137o46.16'E), the top of the Pungalina Member. The second part of the type section, designated as the holostratotype, encompasses the sandstone-dominated upper Echo Sandstone. It is the cliffs adjacent to Masterton Cave, extending from 792500E 8099880N (17o10.01'S, 137o45.03'E; base) to 792150E 8100200N (17o09.84'S, 137o44.75'E; top). The bottom of this section contains the Pungalina Member-upper Echo Sandstone contact (but this is better exposed at 792940E 8099840N - 17o10.05'S, 137o45.25'E). REFERENCE AREAS/SECTIONS: The partly faulted outcrops in northern Foelsche Inlier near 16o55.5'S, 136o29.5'E (southeastern Bauhinia Downs sheet) provide a reference area for the Echo Sandstone and Pungalina Member. The upper unconformable contact with mudstone of the Mallapunyah Formation is well exposed at 658450E 8128970N. A nearby useful reference section is the drillhole intersection 580-745 m in DDH Wearyan 1 drilled at 656320E 8139820N (Bauhinia Downs). Drillcore is available for inspection at the NTGS Core Library, Darwin.|16-MAY-23
33173|Echo Sandstone|Extent|Exposed on the Wearyan Shelf (Plumb and Wellman, 1987), being constrained mostly to the Calvert Hills & Robinson River 1:250 000 sheet areas. It also includes a western extension into the Foelsche Inlier on Bauhinia Downs sheet.|16-MAY-23
33173|Echo Sandstone|Thickness range|>160 m.|16-MAY-23
33173|Echo Sandstone|Lithology|Dominantly pink to white, fine- to coarse-grained quartzose and lithic sandstone with locally scattered pebbles or cobbles. It is cross-bedded with symmetrical to slightly asymmetrical ripples, current lineation and rare mudclasts. Local lower unit (Pungalina Member) of cobble/boulder conglomerate, sandstone and mudstone.|16-MAY-23
33173|Echo Sandstone|Depositional environment|High-energy shallow water environment, with aeolian influences locally.|16-MAY-23
33173|Echo Sandstone|Relationships and boundaries|Locally includes the Pungalina Member, a lateral facies variant of the basal Echo Sandstone. The Echo Sandstone conformably to unconformably overlies the Gold Creek Volcanics, Hobblechain Rhyolite and locally, the Wollogorang Formation. It is in turn unconformably overlain by the Karns Dolomite in the east, the Mallapunyah Formation in the northern Foelsche Inlier, and Bukalara Sandstone and younger cover elsewhere.|16-MAY-23
33173|Echo Sandstone|Age reasons|Palaeoproterozoic. Constrained by SHRIMP U-Pb zircon dates of ~1725 Ma for underlying Hobblechain Rhyolite and ~1640 Ma for the overlying middle McArthur Group (Page and Sweet, 1998).|16-MAY-23
33173|Echo Sandstone|Correlations|Warramana Sandstone in the Batten Fault Zone.|16-MAY-23
33173|Echo Sandstone|Comments|The outcrops now assigned to the Echo Sandstone were initially defined as part of the 'Masterton Formation' by Roberts et al. (1963), which included various sedimentary and volcanic units on the Wearyan Shelf. The type area was adjacent to Masterton Cave near Redbank Mine (not far from the proposed type section of the Echo Sandstone). Jackson et al. (1987) suggested that the sandstone-dominated part should be separated as a discrete entity, the Masterton Sandstone. They nominated Archies Creek, near Mallapunyah Station, as the type section, even though it is a considerable distance from the place where the name `Masterton? was derived. Subsequently, the sandstone sequence exposed at Archies Creek has been found to contain a significant internal disconformity and hiatus, dividing distinctly different lower and upper sandstones. Correlation of the lower sandstone with the originally defined `Masterton Formation? is considered uncertain, and the upper part of the type section correlates with the Masterton Sandstone mapped at the base of the McArthur Group within the Batten Fault Zone by Jackson et al. (1987), Pietsch et al. (1991) and Haines et al. (1993). Consequently, to minimise confusion and retain consistency with recent published maps, the sandstone unit exposed widely on the Wearyan Shelf is renamed here the Echo Sandstone, and the sandstone unit at the base of the McArthur Group retains the name Masterton Sandstone.|16-MAY-23
33173|Echo Sandstone|References|AHMAD M. & WYGRALAK A. S. 1989. Calvert Hills, Northern Territory; 1:250 000 Metallogenic Map Series, sheet SE53-8. Northern Territory Geological Survey Map and Explanatory Notes. **JACKSON M. J., MUIR M. D. & PLUMB K. A. 1987. Geology of the southern McArthur Basin, Northern Territory. Bureau of Mineral Resources, Australia, Bulletin 220, 173pp. **HAINES P. W., PIETSCH B. A., RAWLINGS D. J. & MADIGAN T. L. 1993. Mount Young, Northern Territory; 1:250 000 Geological Map Series, sheet SD53-15. Northern Territory Geological Survey, Explanatory Notes. **PAGE R. W. & SWEET I. P. 1998. Geochronology of basin phases in the western Mount Isa Inlier, and correlation with the McArthur Basin. Australian Journal of Earth Sciences 45, 219-232. **PIETSCH B. A., RAWLINGS D. J., CREASER P. M., KRUSE P. D., AHMAD M., FERENCZI P. A. & FINDHAMMER T. L. R. 1991. Bauhinia Downs, Northern Territory; 1:250 000 Geological Map Series, sheet SE53-3. Northern Territory Geological Survey, Map and Explanatory Notes. **PLUMB K. A. & WELLMAN P. 1987. McArthur Basin, Northern Territory; mapping of deep troughs using gravity and magnetic anomalies. BMR Journal of Australian Geology and Geophysics 10, 243-251. **ROBERTS H. G., RHODES J. M. & YATES K. R. 1963. Calvert hills, N.T.; 1:250,000 geological series, sheet SE53-8. Bureau of Mineral Resources, Geology and Geophysics, Map and Explanatory Notes. **YATES K. R. 1965. Robinson River, N.T.; 1:250,000 geological series, sheet SE53-4. Bureau of Mineral Resources, Geology and Geophysics, Map and Explanatory Notes.|16-MAY-23
5978|Edith River Group|Name source|Edith River, Katherine 1:100 000 Sheet area.|16-MAY-23
5978|Edith River Group|Unit history|Includes all areas previously called Edith River Volcanics on the Katherine and Eva Valley 1:100 000 Sheet areas, and the former Plum Tree Creek Volcanic and Kurrundie Members of the Kombolgie Formation as mapped by Walpole & others (1968).|16-MAY-23
5978|Edith River Group|Constituents|Consists of a main volcanic unit (Plum Tree Creek Volcanics) conformably underlain by three separate discontinuous fluviatile sandstone sequences (the Kurrundie, Phillips Creek and Hindrance Creek Sandstones).|16-MAY-23
5978|Edith River Group|Extent|Extensive outcrops over an area about 5000 km2 between Katherine, Eva Valley and El Sherana (Ranford Hill, Mundogie, Katherine, Stow and Eva Valley 1:100 000 Sheet areas).|16-MAY-23
5978|Edith River Group|Thickness range|Ranges up to 1300 m.|16-MAY-23
5978|Edith River Group|Lithology|Predominantly a sequence of ignimbrite, rhyolite, basalt, dolerite, tuff with minor shale and sandstone (Plum Tree Creek Volcanics) with discontinuous basal fluviatile sequences of quartz sandstone, conglomerate, siltstone and shale (the Kurrundie, Phillips Creek and Hindrance Creek Sandstones).|16-MAY-23
5978|Edith River Group|Relationships and boundaries|Unconformably overlies metamorphosed rocks of the Pine Creek Geosyncline (1800 m.y.), the El Sherana Group and the Cullen Granite Complex (1780-1730 m.y.). Unconformably overlain by the Kombolgie Formation (1650 m.y.). Intruded by the Grace Creek Granite which may be cogenetic with the Plum Tree Creek Volcanics.|16-MAY-23
5978|Edith River Group|Age reasons|Early Proterozoic (1780-1650 m.y., see above).|16-MAY-23
5978|Edith River Group|Proposed publication|Geological map Commentary Mundogie 1:100 000 Sheet|16-MAY-23
5978|Edith River Group|Status|1|16-MAY-23
26302|Edmirringee Volcanics|Name source|Edmirringee Rockhole on Whistleduck Creek, GR 840210 (latitude 20o37'00"S, longitude 134o51'00"E), NE Davenport Range 1:100 000 Sheet area, Bonney Well 1:250 000 Sheet area.|16-MAY-23
26302|Edmirringee Volcanics|Type section locality|6 km NE of Edmirringee Rockhole. From base at GR 864282, the section extends SE for 3.5 km to top at GR 883224, Davenport Range 1:100 000 Sheet area. Here, a SE-ly dipping sequence of basaltic lavas with minor interlayered volcaniclastic arenite and siltstone overlies quartz-feldspar porphyry of the Epenarra Volcanics, and is overlain by, or faulted against, arenite of the Kurinelli Sandstone.|16-MAY-23
26302|Edmirringee Volcanics|Extent|Crops out in Skinner Pound, S and W of Kurundi homestead, and in plain immediately N of Edmirringee Rockhole, in Davenport Range and SW part of Ooradidgee 1:100 000 Sheet areas, Bonney Well 1:250 000 Sheet area.|16-MAY-23
26302|Edmirringee Volcanics|Thickness range|Ranges between 850 m and 2500 m.|16-MAY-23
26302|Edmirringee Volcanics|Lithology|Epidotised amygdaloidal porphyritic and non-porphyritic basalt (50-54% SiO2), scoriaceous basalt, and flow-margin breccia; some dacite and rhyolite; abundant volcaniclastic (largely basaltic) siltstone and arenite in outcrop area SW of Kurundi homestead.|16-MAY-23
26302|Edmirringee Volcanics|Relationships and boundaries|Conformably overlies and laterally interfingers with Epenarra Volcanics; interfingers with and conformably overlain by Kurinelli Sandstone, and by Unimbra Sandstone where Kurinelli Sandstone is absent. Bottom marked by sharp change from arenite or felsic volcanics of Epenarra Volcanics to basalt of Edmirringee Volcanics; top by sharp change from basalt to lithic arenite of Kurinelli Sandstone or quartz arenite of Unimbra Sandstone.|16-MAY-23
26302|Edmirringee Volcanics|Age reasons|Younger than 1870 Ma (U-Pb zircon date on volcanics of Warramunga Group unconformable below Hatches Creek Group) and older than 1640 Ma (Rb-Sr whole-rock approximate date on granite intruding Hatches Creek Group).|16-MAY-23
26302|Edmirringee Volcanics|Comments|Remarks: Part of the Ooradigee Subgroup of the Hatches Creek Group. Distinctive unit compositionally different from overlying arenite units and from felsic volcanic unit which laterally interfingers with it.|16-MAY-23
26302|Edmirringee Volcanics|Proposer|Stewart A.J.|16-MAY-23
24261|El Sherana Group|Name source|El Sherana, Latitude 13o31'S, Longitude 132o31'E Stow 1:100 000 Sheet area.|16-MAY-23
24261|El Sherana Group|Unit history|Previously mapped north of Latitude 13o45'S as Edith River Volcanics. Included in the Burrell Creek Formation in most of the Katherine, and all of the Eva Valley and Maranboy 1:100 000 Sheet areas by Walpole & Others (1968).|16-MAY-23
24261|El Sherana Group|Constituents|Scinto Breccia, Coronation Sandstone, Pul Pul Rhyolite, Big Sunday Formation and Tollis Formation.|16-MAY-23
24261|El Sherana Group|Extent|Well exposed around the base of the Mount Callanan and Edith Basins in the Mundogie, Ranford Hill, Katherine, Eva Valley, Maranboy and Stow 1:100 000 Sheet areas.|16-MAY-23
24261|El Sherana Group|Thickness range|Up to 2500 metres.|16-MAY-23
24261|El Sherana Group|Lithology|A conformable sequence of volcanic and sedimentary rocks consisting of a basal fluviatile valley fill sequence of sandstone, conglomerate and mixed felsic pyroclastic and sedimentary rocks (Coronation Sandstone); minor discontinuous basal breccias (Scinto Breccia); a massive rhyolite and ignimbrite sequence (Pul Pul Rhyolite); and an upper sequence of mixed greywackes, tuffs, rhyolite, ignimbrite and basalt (the Big Sunday and Tollis Formations).|16-MAY-23
24261|El Sherana Group|Relationships and boundaries|Unconformably overlies metamorphosed Early Proterozoic rocks of the Pine Creek Geosyncline (1800 m.y.), unconformably overlain by the Edith River Group. Intruded by the Cullen Granite Complex (1780-1730 m.y.)|16-MAY-23
24261|El Sherana Group|Age reasons|Late Early Proterozoic (1800-1730 m.y.)  See above.|16-MAY-23
24261|El Sherana Group|Proposed publication|Geological map Commentary Mundogie 1:100 000 Sheet area|16-MAY-23
24261|El Sherana Group|Proposer|Stuart-Smith P.G.|16-MAY-23
24261|El Sherana Group|Resdate|09-MAR-1983|16-MAY-23
26534|Elcho Island Formation|Name source|Elcho Island on boundary between Arnhem Bay and Wessel Islands 1:250 000 map sheet areas (latitude 12o00'S, longitude 135o40'E).|16-MAY-23
26534|Elcho Island Formation|Geomorphic expression|Rocky wave cut platforms and cliffs along the coast. Low hills inland.|16-MAY-23
26534|Elcho Island Formation|Type section locality|Plumb and Roberts (1992) only nominated a reference area (see below) and no boundary stratotypes. Lower boundary stratotype at AMG NG043313 (latitude 12o18'S, longitude 135o02'20"E), a sharp slightly erosive contact between white, medium-grained quartz-rich sandstone of the Marchinbar Sandstone below, and friable fine-grained, red-brown, flaggy sandstone of the Elcho Island Formation. Top stratotype at AMG NG223477 (latitude 12o14'S, longitude 135o12'20" E) on Banyan Island, considered to be approximately the top-most exposed beds of the formation. The actual contact with the Jigaimara Formation is not exposed, but the Jigaimara Formation outcrops to the west along ther same coast at a stratigraphically slightly higher position. There are no sections through the Elcho Island Formation, the type locality here nominated as the scattered outcrops between the boundary stratotypes (23 km apart and somewhat oblique to the outcrop trend). The sequence is considered to be uniformly dipping gently (average about 3o) north in this area.  Reference locality: As nominated by Plumb and Roberts (1992), the cliffs near Galiwinku (AMG NG615700) on Elcho Island, however other isolated outcrops on Elcho Island are now excluded. This is the most continuous outcrop of the unit, but is not considered representative of the entire formation.|16-MAY-23
26534|Elcho Island Formation|Extent|Wessel Islands, Arnhem Bay and Milingimbi 1:250 000 scale map sheet areas.|16-MAY-23
26534|Elcho Island Formation|Thickness range|A thickness of 650-700 m is estimated in the vicinity of the Woolen River area, just east of the type locality.|16-MAY-23
26534|Elcho Island Formation|Lithology|Fine- to coarse-grained, thin- to medium-bedded sandstone, generally interbedded with minor mudstone. Locally glauconitic and often ferruginised. The sequence is sometimes calcareous or dolomitic, and chert breccia and leached rocks after carbonates are present locally.|16-MAY-23
26534|Elcho Island Formation|Depositional environment|Shallow marine. Local evidence of evaporitic conditions and exposure.|16-MAY-23
26534|Elcho Island Formation|Relationships and boundaries|Overlies the Marchinbar Sandstone. Boundary picked where white, medium-grained, quartz-rich sandstone is succeeded by flaggy, brown, fine-grained sandstones and mudstones. The boundary seems to be regionally concordant, but at the only location where it is well exposed (lower boundary stratotype) it is slightly erosive and is possibly a sequence boundary. Overlain by the Middle Cambrian Jigaimara Formation with probable disconformity or unconformity. Boundary not exposed, but picked below fossiliferous chert and silicified calcareous siltstone. Top exposed beds of the Elcho Island Formation are sandstones. Overlain unconformably by Cretaceous and Cainozoic deposits.|16-MAY-23
26534|Elcho Island Formation|Age reasons|No fossils have been found. Units lower in the group contain Neoproterozoic fossils (Rawlings and others, in prep.), while the overlying (probably disconformable or unconformable) Jigaimara Formation is Middle Cambrian (Plumb and others, 1976). Probably Neoproterozoic.|16-MAY-23
26534|Elcho Island Formation|Defn author|Plumb K.A., 1965    RDEF Haines P.W.|16-MAY-23
26534|Elcho Island Formation|Proposed publication|Arnhem Bay-Gove 1:250 000 Geological Map Series, Northern Territory, National Geoscience Mapping Accord, Explanatory Notes (Rawlings and others, in prep.).|16-MAY-23
26534|Elcho Island Formation|Comments|This redefinition is considered necessary as the loose reference area nominated by Plumb and Roberts (1992) represents only a portion of the unit mapped by Dunnel (1965) as Elcho Island Formation, contains no boundary stratotypes, and includes younger rocks now separated as the Jigaimara Formation, i.e. the fossiliferous Middle Cambrian rocks identified by Plumb and others (1976).|16-MAY-23
26534|Elcho Island Formation|Defn approved by|Brakel A.T./Haines P.W.|16-MAY-23
25892|Elkedra Granite|Name source|Elkedra pastoral property, in the Elkedra 1:250 000 Sheet.|16-MAY-23
25892|Elkedra Granite|Type section locality|Vicinity of the Juggler mine, around GR 480250, Elkedra 1:100 000 Sheet area, where the main varieties of Elkedra Granite form tors, spheroidal boulders and rock pavements at latitude 21o29'00"S, longitude 135o28'30"E.|16-MAY-23
25892|Elkedra Granite|Extent|Confined to an area of about 12 km2 in SE corner of Elkedra and SW corner of George Creek 1:100 000 Sheet areas, Elkedra 1:250 000 Sheet area.|16-MAY-23
25892|Elkedra Granite|Lithology|Pale pink, medium to coarse, even-grained to slightly megacrystic, homogeneous leucogranite; minor medium-grained tourmaline granite, greisen, aplite, quartz+feldspar+/-tourmaline pegmatite, and quartz-tourmaline veins. The leucogranite consists of about equal amounts of quartz (variably strained), subhedral oligoclase, and perthitic microcline, and up to 10% muscovite and subordinate biotite (partly altered to chlorite).|16-MAY-23
25892|Elkedra Granite|Relationships and boundaries|Intrudes the Rooneys Formation of the Ooradidgee Subgroup of the Hatches Creek Group and a granophyre sill, and has a metamorphic aureole about 100 m wide; is cut by quartz veins and overlain by flat-lying Cambrian strata (Sandover beds). Intrusive roof and side contacts well exposed near the Juggler-mine.|16-MAY-23
25892|Elkedra Granite|Age reasons|About 1640 m.y. (Rb-Sr whole-rock approximate age).|16-MAY-23
25892|Elkedra Granite|Comments|Remarks: Mapped as unnamed granite by Smith & :Milligan (1966); named Elkedra Granite, but not defined, by Compston & Arriens (1968). Emplaced after the main deformation of the Hatches Creek Group had taken place.|16-MAY-23
6073|Elkera Formation|Name source|Elkera No. 1 Bore, Huckitta 1:250 000 Sheet area.|16-MAY-23
6073|Elkera Formation|Unit history|The upper part of the Grant Bluff Formation of Smith (1964) and part of the Central Mount Stuart Beads as shown on the Alcoota 1:250 000 Geological Series Sheet.|16-MAY-23
6073|Elkera Formation|Type section locality|Southwestern Jervois Range, on a section oriented NW-SE through Valley Bore (section 15 of Walter, 1979). Thicknesses are extrapolated from section 10 of Smith (1964).|16-MAY-23
6073|Elkera Formation|Extent|Huckitta, Alcoota and possibly Mt Peake 1:250 000 Sheet areas.|16-MAY-23
6073|Elkera Formation|Thickness range|220 m in the type section, 70 m in the SE Elyuah Range where the upper part of the formation has apparently been lost by erosion during the earliest Cambrian, 80-240 m elsewhere. Thickness variations seem mostly to be due to the level of sub-Cambrian erosion.|16-MAY-23
6073|Elkera Formation|Lithology|Interbedded siltstone, dolomite, sandstone and shale. The siltstone where fresh is green-grey, red-brown, and a very distinctive blue-grey to blue-green colour. The lower dolomites are medium to dark-brown, yellow or grey, and frequently contain poorly preserved columnar branching stromatolites. The upper dolomite is yellow-brown to pink, laminated and oolitic and contains the columnar stromatolite Georgina howchini Walter. The sandstone is light grey to red-brown and locally is identical to that in the underlying Grant Bluff Formation. The section identified as Elkera Formation in drill hole DDC 1 (cores stored by NT Geological Survey, Alice Springs) near Mt Skinner contains anhydrite, dolomite nodules after anhydrite, and carbonate pseudomorphs after gypsum; this facies has not been recognised in outcrop.|16-MAY-23
6073|Elkera Formation|Relationships and boundaries|The lower boundary is placed at the top of the ridge-forming sandstones of the Grant Bluff Formation (Walter, 1979). This is considered to be conformable. The upper boundary in the Huckitta 1:250 000 Sheet area is placed at the base of green and grey siltstone and sandstone at the base of the Mt Baldwin Formation (as redefined here) or, in the Mopunga Range, at the base of the archaeocyathan-bearing carbonates. In DDC 1 from near Mt Skinner the top is placed at the top of the highest prominant carbonate bed. The upper boundary is a disconformity in the Huckitta Sheet area but is conformable at Mt Skinner.|16-MAY-23
6073|Elkera Formation|Age reasons|Adelaidean. The unit correlates with the Julie Formation and the upper Pertatataka Formation of the Amadeus Basin.|16-MAY-23
6073|Elkera Formation|State(s)|NT (Georgina Basin)|16-MAY-23
24266|Ella Creek Member|Name source|Ella Creek; GR 265850; Noonamah 1:100 000 Sheet (5172).|16-MAY-23
24266|Ella Creek Member|Unit history|Malone 1962 included these beds in the now defunct Golden Dyke Formation.|16-MAY-23
24266|Ella Creek Member|Type section locality|10 m of well bedded massive ironstone containing quartz flake breccia and rare paraquartzite nodules in ridge 3 km north-east of Darwin River dam wall, GR 716585835; Bynoe 1:100 000 Sheet (5072).|16-MAY-23
24266|Ella Creek Member|Extent|The unit is exposed as a prominent EW ridge of up to 6 km in length in the central eastern part of the Bynoe 1:100 000 Sheet area (5072).|16-MAY-23
24266|Ella Creek Member|Thickness range|Range 2 to 10 metres.|16-MAY-23
24266|Ella Creek Member|Lithology|Massive goethitic ironstone with paraquartzite breccia; quartz flake breccia with rare quartz nodules in fine grained goethitic matrix; chert breccia with oolites or pisolites in ferruginous sandy matrix; rare ferruginous quartz greit, pebble and boulder conglomerate.|16-MAY-23
24266|Ella Creek Member|Relationships and boundaries|Unconformably overlies Wildman Siltstone (Needham and Stuart-Smith, 1978) and conformably overlain by siltstones and shales of Koolpin Formation (Walpole, 1962). Low angle unconformity exists between Koolpin Formation and Wildman Siltstone in Mary River Sheet area (5272) (Stuart-Smith et al., 1981). Variability of lithologies of this member of the Koolpin Formation prohibits defining lithologies characteristic of its base and top but all lithologies are ferruginous and distinctive from underlying and overlying lithologies.|16-MAY-23
24266|Ella Creek Member|Age reasons|Part of sedimentary sequence unconformably overlying granitic complexes having a minimum date of 2400 Ma (Page, 1980) and intruded by granites dated at c. 1750 Ma (Walpole et al., 1968). Therefore is Early Proterozoic in age.|16-MAY-23
24266|Ella Creek Member|Proposed publication|BMR Report; Rum Jungle Special 1st ed. 1:100 000 map|16-MAY-23
29773|Ellery Granitic Complex|Name source|Ellery Creek.|16-MAY-23
29773|Ellery Granitic Complex|Unit history|Previously mapped as possible Burt Bluff Gneiss and unassigned felsic rocks (Offe, 1981).|16-MAY-23
29773|Ellery Granitic Complex|Geomorphic expression|Rubble-covered ridges.|16-MAY-23
29773|Ellery Granitic Complex|Type section locality|(Reference localities): 1. Megacrystic granitic gneiss GR 31500 7383000; 2. granitic gneiss GR 3032 7380100; 3. hornblende granitic gneiss GR 312200 7383900; all in MacDonnell Ranges 1:100 000 Sheet area.|16-MAY-23
29773|Ellery Granitic Complex|Extent|North of the Chewings Range, from near Old Hamilton Downs homestead to northwest of Fish Hole on Ellery Creek, in a number of seperate plutons. South of the Chewings Range from west of Mount Conway to south of Mount Giles.|16-MAY-23
29773|Ellery Granitic Complex|Lithology|Megacrystic biotite-rich granitic gneiss, granitic gneiss, augen gneiss, leucocratic granitic gneiss, hornblende granitic gneiss.|16-MAY-23
29773|Ellery Granitic Complex|Relationships and boundaries|Intrudes Boggy Hole gneiss, Ryans Gap Metamorphics and Lovely Hill Schist, possibly also in part overlain by Lovely Hill Schist and Chewings Range Quartzite, and is intruded by unnamed granite (Considered equivalent to Old Hamilton Downs Gneiss in the Alice Springs Sheet area) and by dykes of Littlers Pegmatite.|16-MAY-23
29773|Ellery Granitic Complex|Structure and Metamorphism|Strongly foliated wide amphibolite facies conditions during the Chewings Orogeny. Minor migmatitised gneiss may represent older material.|16-MAY-23
29773|Ellery Granitic Complex|Age reasons|Middle Proterozoic: affected by regional metamorphism at about 1590 Ma.|16-MAY-23
29773|Ellery Granitic Complex|Correlations|Includes units equivalent to Ormiston Pound Granite, Burt Bluff Gneiss.|16-MAY-23
29773|Ellery Granitic Complex|Defn author|R.D. Shaw, R.G. Warren & G. Wakelin-King, 1991.|16-MAY-23
29773|Ellery Granitic Complex|Comments|This 'definition' is missing the details of references mentioned in the synonymy, and shows no signs on the card of having been approved.|16-MAY-23
6118|Elyuah Formation|Type section locality|Smith (1964), BMR Report 67, shows the location of the type section of the Elyuah Formation in fig.6, p21, but no co-ordinates are given and the figure is hard to correlate with the prelim. Huckitta 1:250k map inluded as Plate 8.|16-MAY-23
6118|Elyuah Formation|Identifying features|This formation was defined by Smith (1964) to include two members, an upper one predominantly of shale and siltstone, and a lower one predominantly of arkose. The lower member, the Oorabra Arkose, has been upgraded to a formation because an unconformity has been recognised between the two former members (Walter, 1979). The name Elyuah Formation is here restricted to the former upper, shale and siltstone, member (which was not originally separately named). The original type section of Smith (1964), X23, is retained. There the formation as now defined has a thickness of 36 m. Smith's (1964) definition of the top of the formation is retained. The base is taken at the base of a thin but persistent sandstone or pebbly arkose underlying the shale and siltstone of which the formation is mostly composed.|16-MAY-23
24269|Enbra Granulite|Name source|Enbra Hills, centred on 23o12'S, 133o82'E in the Alice Springs 1:250 000 Sheet area.|16-MAY-23
24269|Enbra Granulite|Unit history|Previously mapped by Wells & others (1968) as undivided Arunta Complex.|16-MAY-23
24269|Enbra Granulite|Type section locality|From Snake Well (GR 5651-856356) to a prominent hill 3 km to the south.|16-MAY-23
24269|Enbra Granulite|Extent|The unit is well exposed in an area of low hills immediately south of Snake Well in Burt 1:100 000 Sheet area.|16-MAY-23
24269|Enbra Granulite|Lithology|Dominantly mafic granulite but includes a small amount of felsic granulite. The mafic granulite is very homogeneous and consists of hypersthene, plagioclase, and hornblende.|16-MAY-23
24269|Enbra Granulite|Relationships and boundaries|Separated from the Erontonga metamorphics and the Sliding Rock metamorphics by Cainozoic cover sediments. However, magnetic data indicate that the unit is faulted against both of these bounding formations.|16-MAY-23
24269|Enbra Granulite|Age reasons|Middle Proterozoic or older. The unit is considered to be a basal member of the Strangways Metamorphic Complex, and as such was probably metamorphosed at 1800 m.y. (Black, 1975).|16-MAY-23
24269|Enbra Granulite|Defn Reference|80/20787|16-MAY-23
24269|Enbra Granulite|Proposer|Langworthy A.P. (in Shaw & others, in preparation)|16-MAY-23
29220|Endurance Sandstone Member|Name source|Endurance tungsten mine, GR 190914, Hatches 1:100 0000 Sheet area, Frew River 1:250 0000 Sheet area.|16-MAY-23
29220|Endurance Sandstone Member|Type section locality|1.5 km east of the Pioneer mine (latitude 20o52'10"S, longitude 135o11'00"E), from GR 200924 (base) to GR 202915 (top). Here typical rock types of the member - thinly interbedded greywacke and siltstone - sipping 45o southeast are intruded by dolerite/gabbro and overlain and underlain by feldspathic quartz arenite of undivided Kurinelli Sandstone.|16-MAY-23
29220|Endurance Sandstone Member|Extent|Southern central Hatches 100 000 Sheet area, near Hatches Creek.|16-MAY-23
29220|Endurance Sandstone Member|Thickness range|0 to about 500 m.|16-MAY-23
29220|Endurance Sandstone Member|Lithology|Recessive, thinly interbedded fine-grained micaceous greywacke and siltstone; minor variably feldspathic quartz arenite of undivided Kurinelli Sandstone type.|16-MAY-23
29220|Endurance Sandstone Member|Relationships and boundaries|Conformable lensoid unit within the Kurinelli Sandstone; intruded by gabbro/dolerite. Contacts with undivided Kurinelli Sandstone, which are generally poorly exposed, are taken at abrupt change in lithology from recessive greywacke and siltstone to ridge-forming arenite.|16-MAY-23
29220|Endurance Sandstone Member|Age reasons|Younger than 1870 m.y. - U-Pb zircon age of volcanics in the Warramunga Group unconformably below the Hatches Creek Group. Older than 1640 m.y. - Rb-Sr whole-rock approximate age of granite intruding the Hatches Creek Group.|16-MAY-23
29220|Endurance Sandstone Member|Comments|Remarks: Generally finer grained, more micaceous, and less quartzose than other parts of the Kurinelli Sandstone. The Kurinelli Sandstone is part of the Ooradidgee Subgroup of the Hatches Creek Group.|16-MAY-23
29220|Endurance Sandstone Member|Defn Reference|86/25362|16-MAY-23
29220|Endurance Sandstone Member|Proposer|Blake D.H.|16-MAY-23
29220|Endurance Sandstone Member|Resdate|07-OCT-1981|16-MAY-23
6195|Ennugan Mountains Granite|Name source|After Ennugan Mountains on NAPPERBY 1:250,000 mapsheet, Tea Tree 1:100 000 and Reynolds Range 1:100 000 mapsheets, and MOUNT PEAKE 1:250 000 mapsheet, Mount Peake 1:100 000 mapsheet, Aileron Province, Arunta Region, Northern Territory.|16-MAY-23
6195|Ennugan Mountains Granite|Unit history|The name 'Ennugan Mountains Granite' was first introduced by Blake et al (1991) (see Australian Stratigraphic Units Database http://dbforms.ga.gov.au/pls/www/geodx.strat_units.sch_full?wher=stratno=6195 ). The name has since been used in a number of publications including Smith (2001), Hussey (2003), Scrimgeour (2013), Kositcin et al (2013) and Beyer et al (2015).|16-MAY-23
6195|Ennugan Mountains Granite|Geomorphic expression|Forms the rugged terrain of the Ennugan Mountains with a maximum relief of approximately 100 m above the surrounding peneplain.|16-MAY-23
6195|Ennugan Mountains Granite|Type section locality|The proposed type locality is located at GDA94 53K 290342E 7554773N (22deg5'58"S 132deg58'4"E) in the southern Ennugan Mountains approximately 7 km east of White Tree Bore,Bore (which is also the site locality for SHRIMP zircon U-Pb geochronology of Kositcin et al 2013). Another two reference areas are nominated as examples of two further principal textural variants (see below), these are: (1) southwest Ennugan Mountains (GDA94 53K 284630E 7570802N, -21deg57'14"S 132deg54'52"E) and (2) northern Ennugan Mountains (GDA94 53K 286407E 7554201N, -22deg6'14"S 132deg55'46"E).|16-MAY-23
6195|Ennugan Mountains Granite|Description at type locality|Well exposed bouldery hills and pavements of fresh to moderately weathered grey porphyritic granite. A common feature at this site is the presence of abundant dark-coloured felsic microgranular enclaves up to a metre long.|16-MAY-23
6195|Ennugan Mountains Granite|Extent|The extent of the granite interpreted from outcrop and undercover using the regional magnetics data suggests that it is roughly ellipsoid with a northwest strike and a long axis of approximately 40 km and short axis of about 15 km.|16-MAY-23
6195|Ennugan Mountains Granite|General description|The porphyritic phase outcrops extensively in the southern and central Ennugan Mountains, the K-feldspar-rich granite is restricted to the southwest and the equigranular granite occurs in the northernmost outcrops, north of a major northwest-trending fault zone. Allanite-bearing granite outcrops locally in the southern Ennugan Mountains.|16-MAY-23
6195|Ennugan Mountains Granite|Lithology|Porphyritic biotite granite with abundant coarse-grained K-feldspar megacrysts up to 4 cm long in a fine-grained groundmass of quartz, K-feldspar, plagioclase and biotite; rare hornblende may be xenocrystic. Notable for the presence of cognate felsic microgranular enclaves, rafts of metasedimentary country rock and discrete zones of biotite schist (see Alteration and mineralisation). Less voluminous phases include strongly porphyritic biotite granite with up to 70% K-feldspar phenocrysts, fine- to medium-grained equigranular biotite +/- hornblende granite and fine-grained equigranular biotite granite with accessory allanite. Late stage dykes comprise biotite microgranite, aplite and quartz-feldspar porphyry. Pegmatite is generally absent.|16-MAY-23
6195|Ennugan Mountains Granite|Depositional environment|Igneous source with minimal crustal contamination, post-tectonic.|16-MAY-23
6195|Ennugan Mountains Granite|Relationships and boundaries|Interpreted to intrude metasedimentary rocks of the Palaeoproterozoic Lander Rock Formation. Contacts are not exposed but rafts of the country rock are recognised in the granite in its southern outcrops. The Vaughan Springs Quartzite of the Ngalia Basin is inferred to unconformably overlie the north eastern part of the granite.|16-MAY-23
6195|Ennugan Mountains Granite|Identifying features|The Ennugan Mountains Granite is distinguished from other Palaeoproterozoic granitoids in the area by its significantly younger age ie ca 1620 Ma compared to 1805-1790 Ma, and lack of the well-developed gneissosity typical of the orthogneiss units in the Reynolds Range to the south of the Ennugan Mountains (Scrimgeour 2013).|16-MAY-23
6195|Ennugan Mountains Granite|Structure and Metamorphism|Weak to moderate, steeply southwest dipping foliation defined by K-feldspar and biotite.|16-MAY-23
6195|Ennugan Mountains Granite|Age reasons|SHRIMP zircon U-Pb ages of 1622 +/- 7 Ma and 1621 +/- 5 Ma, (Smith 2001, Kositcin et al 2013), interpreted as the magmatic crystallisation age of the Ennugan Mountains Granite. A dyke of biotite microgranite in the southern Ennugan Mountains has a SHRIMP zircon U-Pb age of 1618 +/- 2 Ma and is interpreted as a late stage phase of the Ennugan Mountains Granite (Kositcin et al 2013).|16-MAY-23
6195|Ennugan Mountains Granite|Alteration and Mineralisation|Locally developed m-scale zones of biotite schist interpreted as metasomatised granite (Beyer 2017). The schists are anomalously enriched in a range of elements including U, Th, P, F and the rare earth elements.|16-MAY-23
6195|Ennugan Mountains Granite|Geophysical Expression|Variable magnetic signature from a low magnetic response with a smooth texture in the southern outcrops to a high-amplitude response in the north. Has a radiometric signature high in all three channels.|16-MAY-23
6195|Ennugan Mountains Granite|Geochemistry|High silica granite of I-type composition.|16-MAY-23
6195|Ennugan Mountains Granite|Defn author|E.E.Beyer, 10-FEB-2017|16-MAY-23
6195|Ennugan Mountains Granite|References|Beyer EE, 2017. Nature and prospectivity of high-heat-producing granites of the central Aileron Province, Northern Territory. Northern Territory Geological Survey, Record 2017-0XX***Beyer EE, Allen CM, Armstrong R and Woodhead JD 2015. Summary of results. NTGS laser ablation ICPMS U-Pb and Hf geochronology project: selected samples from NAPPERBY 1:250 000 mapsheet area, Arunta Region, July 2010-January 2012. Northern Territory Geological Survey, Record 2015- 009.***Blake D, Griffin T, Tyler I, Edgoose C, Young D, Shaw R, Black L and Warren G, 1991. National Geoscience Mapping Accord: Preliminary results of the Kimberley - Arunta project. BMR Research Newsletter, 14, 9-12.***Hussey KJ, 2003. Rare earth element mineralisation in the eastern Arunta Region. Northern Territory Geological Survey, Record 2003-004.***Kositcin N, Beyer EE, Whelan JA, Close DF, Hallett L and Dunkley DJ. 2013. Summary of results. Joint NTGS - GA geochronology project: Arunta Region, Ngalia Basin, Tanami Region and Murphy Province, July 2011- June 2012. Northern Territory Geological Survey, Record 2013-004.***Scrimgeour IR, 2013. Aileron Province: in Ahmad M and Munson TJ (compilers) 'Geology and mineral resources of the Northern Territory.' Northern Territory Geological Survey, Special Publication 5.***Smith J, 2001. Summary of results. Joint NTGS-AGSO age determination program. Northern Territory Geological Survey, Record 2001-007.|16-MAY-23
27287|Epenarra Volcanics|Name source|Epenarra homestead, GR 272394, Epenarra 1;100 0000 Sheet area, Frew River 1:250 000 Sheet area.|16-MAY-23
27287|Epenarra Volcanics|Unit history|Much of the formation was previously mapped partly as Warramunga Group and partly as granite or intrusive porphyry (e.g. Smith, 1970 - Bonney Well 1:250 000 Explanatory Notes).|16-MAY-23
27287|Epenarra Volcanics|Type section locality|Northeast of Cannagootchoo Rockholes (latitude 30o13'00"S, longitude 134o23'55"E) in the Murchison Range, Bonney 1:100 000 Sheet area, from GR 393659 (base) to GR 383659 (top). In this section th formation is about 550 m thick, dips about 35o west, and consists of iron-stained felsic lava flows and interlayered quartzose to volcaniclastic arenite, pebbly arenite, and conglomerate. It is unconformable on the Warramunga Group (actual contact is east-southeast), and is overlain conformably by the Unimbra Sandstone.|16-MAY-23
27287|Epenarra Volcanics|Extent|Restricted to northern part of the Davenport Province - Bonney, Ooradidgee and Davenport Range 1;100 000 Sheet areas, Bonney Well 1:250 000 Sheet area, and Epenarra and Hatches 1:100 000 Sheet areas, Frew River 1:250 000 Sheet area.|16-MAY-23
27287|Epenarra Volcanics|Thickness range|0 to possibly more than 3000 m.|16-MAY-23
27287|Epenarra Volcanics|Lithology|Generally recessive volcanics - felsic lava, ignimbrite, agglomerate, lappilli tuff, thin-bedded to laminated tuff, and minor possible mafic lava (very altered) - and interlayered, partly ridge-forming, quartzose to volcaniclastic arenite, pebbly arenite, and conglomerate. Rocks locally cleaved, commonly shades of purple or reddish-brown. Felsic lava contains small phenocrysts of feldspar (generally pseudomorphed) +/- partly resorbed quartz +/- pseudomorphed ferromagnesian minerals.|16-MAY-23
27287|Epenarra Volcanics|Relationships and boundaries|Unconformable on the Warramunga Group, intrusive feldspar porphyry unnamed leucogranite. Overlain conformably by, and locally interfingers with, thinly bedded greywacke and siltstone of the Rooneys Formation, basaltic lavas of the Edmirringee Volcanics, pale buff or grey feldspathic/lithic quartz arenite of the Kurinelli Sandstone, and white or pale pink quartzose arenite of the Unimbra Sandstone. Arenites of the Epenarra Volcanics are distinguished from those of adjacent formations by purplish or reddish-brown colour and volcaniclastic content. The formation is intruded by granophyre, microgranite, and dolerite, and is overlain unconformably by Cambrian and younger beds.|16-MAY-23
27287|Epenarra Volcanics|Age reasons|Younger than 1870 m.y. - U-Pb zircon age for volcanics in the Warramunga Group unconformably underlying the Hatches Creek Group. Older than 1640 m.y. - Rb-Sr whole-rock approximate age for granite intruding the Hatches Creek Group.|16-MAY-23
27287|Epenarra Volcanics|Comments|Remarks: Partly equivalent stratigraphically to, but separated geographically from, two lithologically distinct felsic volcanic units - Treasure Volcanics and Mia Mia Volcanics - which crop out to the south. Part of the Ooradidgee Subgroup of the Hatches Creek Group.|16-MAY-23
27287|Epenarra Volcanics|Defn Reference|86/25362|16-MAY-23
27287|Epenarra Volcanics|Proposer|Blake D.H.|16-MAY-23
27287|Epenarra Volcanics|Resdate|07-OCT-1981|16-MAY-23
21753|Erringkarri Rhyolite|Name source|Erringkarri (GR PE2480), an Aboriginal place name located on the North Bay, Bickerton Island, BLUE MUD BAY.|16-MAY-23
21753|Erringkarri Rhyolite|Unit history|Formerly mapped as part of the now abandoned 'Bickerton Volcanics' (Plumb and Roberts, 1965, 1992).|16-MAY-23
21753|Erringkarri Rhyolite|Geomorphic expression|Wave-cut platforms and cliffs along the coast beneath Abarungkwa Sandstone.|16-MAY-23
21753|Erringkarri Rhyolite|Type section locality|Upper boundary stratotype: Southern shoreline of North BAy on Bickerton Island (lat. 13o 45'S, long. 136o 10'E; GR PE260790), where approximately 20m of section is exposed.|16-MAY-23
21753|Erringkarri Rhyolite|Extent|Outcrop restricted to shore of North Bay on Bickerton Island, BLUE MUD BAY.|16-MAY-23
21753|Erringkarri Rhyolite|Thickness range|Known outcrops are almost 20m thick; the base is not exposed.|16-MAY-23
21753|Erringkarri Rhyolite|Depositional environment|Terrestrial, probably formed large domes and coulees.|16-MAY-23
21753|Erringkarri Rhyolite|Relationships and boundaries|No base exposed but probably lies unconformably on Grindall Formation. Overlain erosionally by Abarungkwa Sandstone at stratotype locality. Lowest unit of the Bustard Subgroup of the Groote Eylandt Group.|16-MAY-23
21753|Erringkarri Rhyolite|Age reasons|Probably Orosirian (Palaeoproterozoic). The similar Bickerton Rhyolite, a little higher in the succession, has been dated at ~1815 Ma (Pietsch et al. 1994).|16-MAY-23
21753|Erringkarri Rhyolite|Correlations|Considered to correlate with the ~1800-1840 Ma felsic volcanic suite widespread in northern Australia (Rawlings, 1994).|16-MAY-23
26303|Errolola Sandstone|Name source|Errolola Rockhole on Frew River, GR 043807, in SW of Hatches 1:100 000 Sheet araea, Frew River 1:250 000 Sheet area.|16-MAY-23
26303|Errolola Sandstone|Type section locality|Immediately E of Coulters Waterhole (latitude 20o59'55"S, longitude 135o01'50"E); base at GR 041780, top at GR 047780. Here the formation is about 500 m thick, dips E at about 70o, and forms a prominent ridge consisting mainly of white medium-bedded medium-grained quartz arenite; cross-bedding and ripple marks common.|16-MAY-23
26303|Errolola Sandstone|Extent|Crops out throughout Davenport Province, in E and central parts of Bonney Well, SW part of Frew River, NW part of Elkedra, and NE part of Barrow Creek 1:250 000 Sheet areas.|16-MAY-23
26303|Errolola Sandstone|Thickness range|Ranges between 100 m and 1200 m.|16-MAY-23
26303|Errolola Sandstone|Lithology|Ridge-forming cross-bedded quartz arenite and subordinate feldspathic/lithic/kaolinic arenite; sparse to abundant pebbles in a few beds, mainly near top and bottom.|16-MAY-23
26303|Errolola Sandstone|Relationships and boundaries|Conformably overlies Kudinga Basalt; conformably overlain by Alinjabon Sandstone. Base marked by change from recessive basalt to ridge-forming arenite; top is abrupt change from ridge-forming arenite to recessive basal beds of Alinjabon Sandstone.|16-MAY-23
26303|Errolola Sandstone|Age reasons|Between 1870 Ma (U-Pb date on zircon is volcanics of Warramunga Group, which is unconformable below Hatches Creek Group), and 1640 Ma (Rb-Sr whole-rock approximate date on granite intruding Hatches Creek Group).|16-MAY-23
26303|Errolola Sandstone|Comments|Remarks: Part of Hanlon Subgroup of Hatches Creek Group. Distinctive resistant clean arenite, readily distinguished from overlying unit of alternating arenite and recessive beds, and from underlying basaltic unit.|16-MAY-23
26303|Errolola Sandstone|Defn Reference|86/25362|16-MAY-23
26303|Errolola Sandstone|Proposer|Stewart A.J.|16-MAY-23
26303|Errolola Sandstone|Resdate|07-OCT-1981|16-MAY-23
70576|Esther Granite|Name source|After Mount Esther (53K 331375mE 7573200mN) in southwestern ANNINGIE.|16-MAY-23
70576|Esther Granite|Unit history|Mapped as unnamed Carpentarian granites Pg, Pgp on First Edition MOUNT PEAKE (Offe 1978). 'Esther Granite' (Donnellan in Cross et al 2005).|16-MAY-23
70576|Esther Granite|Geomorphic expression|Typically low whalebacks and bouldery nubbins.|16-MAY-23
70576|Esther Granite|Type section locality|At 312242mE 7595271mN (21o44'05"S 133o11'09"E) near Old Yards Well in ANNINGIE (which is also the sample site for SHRIMP single-crystal zircon U-Pb geochronology (Cross et al (2005)).  Reference areas: Three reference areas are nominated as examples of the further principal textural variants (see below); these are: (1) around Central Mount (318248mE 7573912mN); (2) north of Mt Esther (329249mE 7574747mN); and (3) near Amesbury Bore (at 314339mE 7596767mN) in ANNINGIE|16-MAY-23
70576|Esther Granite|Extent|Outcrops sporadically over an area of ~650 km2 in southern ANNINGIE from Mt Esther to Mt Judith, Central Mount, Amesbury Bore and Walabanba Hills. Airborne magnetic and regional gravity data indicate that the granite does not extend widely beyond the limits of these scattered outcrops, but suggests that it may extend locally into northeastern NAPPERBY, northwestern ALCOOTA and southwestern BARROW CREEK.|16-MAY-23
70576|Esther Granite|Lithology|Grey biotite granite, typically with K-feldspar megacrystic texture. At least four textural variants recognised. First variant (Pge) characterised by extremely large (up to 15 cm), elongate K-feldspar megacrysts. This variant outcrops around Old Yards Well and Walabanba Hills. Second textural variant (Pge1) has equidimensional K-feldspar megacrysts up to approximately 5 cm size and is represented around Mt Esther. Third variant (Pge2) well represented around Central Mount and characterised by inequidimensional, but much smaller (1.5-2 cm) K-feldspars. A fourth, minor variant is coarse to very coarse, equigranular or seriate porphyritic; this variant occurs in vicinity of Amesbury Bore but is not mapped separately. Pegmatite is an additional constituent.|16-MAY-23
70576|Esther Granite|Relationships and boundaries|Intrudes Lander Rock Formation; unconformably overlain by Boko, Grant Bluff and Central Mount Stuart Formations and by unnamed, probable Neoproterozoic basalt. Coarse andalusite porphyroblasts in Lander Rock Formation proximal to Esther Granite are attributed to probable contact metamorphism.|16-MAY-23
70576|Esther Granite|Age reasons|Statherian, based on SHRIMP single-crystal zircon U-Pb igneous crystallisation age of 1789 ± 6 Ma (Cross et al 2005).|16-MAY-23
70576|Esther Granite|Correlations|Unnamed granites Pg2 and Pg2m on Second Edition MOUNT PEAKE (Donnellan in prep, Donnellan and Johnstone in prep).|16-MAY-23
70576|Esther Granite|References|Cross A, Claoué-Long JC, Scrimgeour IR, Crispe A and Donnellan N, 2005. Summary of results. Joint NTGS-GA geochronology project: northern Arunta and Tanami regions 2000-2003. Northern Territory Geological Survey, Record 2005-003.Offe LA, 1978. Mount Peake, Northern Territory. 1:250 000 geological series explanatory notes, SF 53-5. Bureau of Mineral Resources, Australia, Canberra.|16-MAY-23
82060|Eurobra Gneiss|Name source|Eurobra Hill (135.825degreesE 22.8558degreesS (GDA2020)) in Jinka 1:100 000 mapsheet, Northern Territory.|16-MAY-23
82060|Eurobra Gneiss|Geomorphic expression|Prominent 20?40 m-high isolated hills, ridges, and patches of partially covered outcrop|16-MAY-23
82060|Eurobra Gneiss|Type section locality|No single outcrop contains all informal and formal subunits. Access to the outcrops are via public roads and private tracks. Some off-track driving/walking might be required. A type locality containing the most voluminous subunit of the Eurobra Gneiss occurs around 135.7824degreesE 22.9128degreesS (GDA2020) and is a small hill of metagreywacke migmatites. Reference localities include a ridge of impure quartzite around 135.7660degreesE 22.9606degreesS (GDA 2020), and isolated outcrop of calc-silicate rocks and marbles around 135.8378degreesE 22.9026degreesS (GDA 2020).|16-MAY-23
82060|Eurobra Gneiss|Description at type locality|Comprises abundant metagreywacke migmatites, The unit is equigranular or porphyroclastic biotite-plagioclase-quartz+/-K-feldspar-muscovite+/-garnet paragneiss, migmatitic with variable amounts of sub-mm to dm-scale leucocratic segregation and local mm-cm-scale compositional layering.|16-MAY-23
82060|Eurobra Gneiss|Extent|Isolated outcrops in southern HUCKITTA 1:250 000 mapsheet (Weisheit et al in prep) south of Anderson Creek and Elua Range, north of Arunta Creek and Harts Range. Possibly more widely distributed in the subsurface and extending into ILLOGWA CREEK.|16-MAY-23
82060|Eurobra Gneiss|General description|The unit contains abundant migmatitic metagreywacke, and is interlayered at the dm- to km-scale with metasandstones, calc-silicate rocks, and marbles. In HUCKITTA, the Eurobra Gneiss is distinguished from the Yambla Gneiss by the metagreywacke migmatites; however, the Yambla Gneiss is migmatitic elsewhere (eg in ILLOGWA CREEK). The Eurobra and Yambla gneisses also have distinct detrital zircon spectra and magnetic character.|16-MAY-23
82060|Eurobra Gneiss|Thickness range|Not observed in type area. The unit is possibly widespread in the subsurface; however, structural repetition is likely. The thickness of original sedimentary units, or their stratigraphic order and an absolute younging direction is difficult to determine because of structural and metamorphic overprint.|16-MAY-23
82060|Eurobra Gneiss|Lithology|Comprises abundant metagreywacke migmatites, with lesser mica-bearing sandstones, calc-silicate rocks, and marbles. Metagreywacke migmatites: equigranular or porphyroclastic biotite-plagioclase-quartz+/-K-feldspar+/-muscovite+/-garnet paragneiss, migmatitic with variable amounts of sub-mm to dm-scale leucocratic segregation; local mm-cm-scale compositional layering. Mica-bearing metasandstones: fine-grained impure quartzite with minor biotite, muscovite, and plagioclase; quartz-plagioclase-biotite gneiss, locally preserved mm- to cm-scale compositional layering. Calc-silicate rocks: fine-grained epidote-calcite-garnet calc-silicate rock, mm-cm-scale compositional layering, foliated.|16-MAY-23
82060|Eurobra Gneiss|Depositional environment|Possibly deposited contemporaneous with Neoproterozoic rocks of the Georgina Basin during a sag phase or in an extensional graben environment. Deformed and metamorphosed during extension followed by compression.|16-MAY-23
82060|Eurobra Gneiss|Relationships and boundaries|Structurally and possibly stratigraphically underlies Yambla Gneiss; intruded by Ghost Gum Granite, Riddock Metagabbro, and pegmatites; unconformably overlain by Cenozoic Waite Formation equivalent.|16-MAY-23
82060|Eurobra Gneiss|Identifying features|This is the only migmatitic metasedimentary succession in the Irindina Province north of the Harts Range and Entia Dome. It is commonly associated with the anatectic Ghost Gum Granite.|16-MAY-23
82060|Eurobra Gneiss|Structure and Metamorphism|North-dipping compositional layering. Faulted contact with overlying Yambla Gneiss. Common m?km-scale, inclined, asymmetric, isoclinal folding. Amphibolite-facies metamorphism, with migmatites occurring in metagreywacke compositions.|16-MAY-23
82060|Eurobra Gneiss|Age reasons|U-Pb zircon maximum depositional age of 1019 +/- 23 Ma SHRIMP (Kositcin and Reno 2020)|16-MAY-23
82060|Eurobra Gneiss|Alteration and Mineralisation|Fresh to strongly weathered.|16-MAY-23
82060|Eurobra Gneiss|Geophysical Expression|Magnetic response is dominantly moderately high with strong magnetic low and high trends; together with Ghost Gum Granite in an area of gravity high response; no characteristic radiometric response.|16-MAY-23
82060|Eurobra Gneiss|Defn author|Barry Reno, Anett Weisheit, Eloise Beyer, Pablo Farias (NT Department of Industry, Tourism and Trade, Northern Territory Geological Survey) 4-MAY-2022.|16-MAY-23
82060|Eurobra Gneiss|References|Kositcin N and Reno BL, 2020. Summary of results. Joint NTGS-GA geochronology project: Aileron and Irindina provinces, Jinka and Dneiper 1:100 000 mapsheets, 2019. Northern Territory Geological Survey, Record 2020-001.  **Reno BL, Weisheit A, Beyer EE and PG Farias, 2022. Jinka, Northern Territory. 1:100 000 geological map series explanatory notes, 6052. Northern Territory Geological Survey, Darwin.  **Weisheit A et al, in prep. Huckitta, Northern Territory (Third Edition). 1:250 000 geological map series explanatory notes, SF53-11. Northern Territory Geological Survey, Darwin.|16-MAY-23
34086|Fairy Glen Sandstone Member|Name source|From Fairy Glen, a small valley around a permanent waterhole on the Walker River, at lat. 13o23.7'S, long. 135o22.7'E, FLEMING 1:100 000 sheet (5971).|16-MAY-23
34086|Fairy Glen Sandstone Member|Unit history|The Fairy Glen Sandstone Member was not distinguished during previous mapping of the Parsons Range Group by Plumb & Roberts (1992), but was described in measured sections as an interval of ferruginous (hematitic) sandstone|16-MAY-23
34086|Fairy Glen Sandstone Member|Geomorphic expression|Forms a distinctive dark reddish-brown-coloured capping on a south- to east-dipping cuesta.|16-MAY-23
34086|Fairy Glen Sandstone Member|Type section locality|Sixteen kilometres northeast of Fairy Glen, the base is at lat. 13o18'20"S, long. 135o29'51.55"E; the top is at lat. 13o18'27"S, long. 135o29'54.88"E.|16-MAY-23
34086|Fairy Glen Sandstone Member|Extent|Outcrops all lie within the Parsons Range, from 4 km south of the headwaters of Matta Murta Creek, in an arcuate belt extending 65 km west, southwest and south, to the southern Parsons Range.|16-MAY-23
34086|Fairy Glen Sandstone Member|Thickness range|Maximum of 100 m in eastern Parsons Range, including at type locality, thinning to 50 m and less in the southwest.|16-MAY-23
34086|Fairy Glen Sandstone Member|Lithology|Medium-grained, swaley and hummocky cross-stratified medium-grained ferruginous sandstone; very fine- to fine-grained, slightly ferruginous, lithic, and clay-rich sandstones more common in central and southern Parsons Range outcrops.|16-MAY-23
34086|Fairy Glen Sandstone Member|Depositional environment|Shallow marine; probably lower to mid-shoreface, based on domination by swaley and hummocky cross-stratified sands.|16-MAY-23
34086|Fairy Glen Sandstone Member|Relationships and boundaries|Member of the Badalngarrmirri Formation, Parsons Range Group. Both lower and upper contacts, although relatively sharp, are believed to be conformable. Base is placed at the change from medium-grained quartz arenite (of informal unit 10a), to ferruginous, porous sandstone. The top is marked by an abrupt change of slope, coinciding with the change from ferruginous sandstone to laminated mudstone, the latter rarely exposed.|16-MAY-23
34086|Fairy Glen Sandstone Member|Age reasons|Palaeoproterozoic: maximum age is well constrained by the age of the uppermost formation of the Donydji Group, the Fagan Volcanics, at 1710 Ma; minimum age is less well constrained, but must be greater than 1620 Ma, the age of the Yarrawirrie Formation in the overlying Balma Group (Pietsch and others, 1994), and most likely older than 1640 Ma, the age of the Barney Creek Formation (Page & Sweet, in press), a correlative of the central Balma Group (Haines, 1994).|16-MAY-23
34086|Fairy Glen Sandstone Member|Correlations|No known correlatives.|16-MAY-23
34086|Fairy Glen Sandstone Member|References|HAINES, P.W., 1994 - The Balma and Habgood Groups, Northern McArthur Basin, Northern Territory: stratigraphy and correlations with the McArthur Group. In HALLENSTEIN, C.P. (Editor), 1994 - AusIMM Annual Conference: 'Australian Mining looks north - the challenges and choices'. Australasian Institute of Mining and Metallurgy, Melbourne, 135-138. **HAINES, P.W., RAWLINGS, D.J., SWEET, I.P., PIETSCH, B.A., PLUMB, K.A., MADIGAN, T.L., & KRASSAY, A.A., 1997 - Blue Mud Bay, 1:250 000 geological series. Northern Territory Geological Survey, Explanatory Notes, SD53 7. **PAGE, R.W., & SWEET, I.P., (in press) - Geochronology of basin phases in the western Mount Isa Inlier, and correlation with McArthur Basin. Australian Journal of Earth Sciences. **PIETSCH, B.A., PLUMB, K.A., PAGE, R.W., HAINES, P.W., RAWLINGS, D.J., & SWEET, I.P., 1994 - A revised stratigraphic framework for the McArthur Basin, N.T. In HALLENSTEIN, C.P. (Editor), 1994 - AusIMM Annual Conference: 'Australian Mining looks north - the challenges and choices'. Australasian Institute of Mining and Metallurgy, Melbourne, 135-138. **PLUMB, K.A., & ROBERTS, H.G., 1992 - The geology of Arnhem Land, Northern Territory. Bureau of Mineral Resources, Australia, Record, 1992/55, 193pp.|16-MAY-23
6584|Fenn Gap Conglomerate Member|Name source|Fenn Gap (GR 36023679) in the Alice Springs 1:250 000 Sheet area.|16-MAY-23
6584|Fenn Gap Conglomerate Member|Unit history|The Heavitree Quartzite has been previously undivided (Wells & others, 1968), except informally in the Arltunga Nappe Complex (Shaw & others, 1971).|16-MAY-23
6584|Fenn Gap Conglomerate Member|Type section locality|Heavitree Gap (GR 3845 3745).|16-MAY-23
6584|Fenn Gap Conglomerate Member|Extent|From Arltunga in central-eastern Alice Springs 1:250 000 Sheet area to Mangeraka Gorge, 43 km west-southwest of Haast Bluff in Mount Liebig 1:250 000 Sheet area.|16-MAY-23
6584|Fenn Gap Conglomerate Member|Thickness range|34 m.|16-MAY-23
6584|Fenn Gap Conglomerate Member|Lithology|Medium to thick-bedded, poorly sorted, argillaceous granule conglomerate and conglomeratic sandstone, which are commonly iron stained brown, pink, and purple, particularly near the base.|16-MAY-23
6584|Fenn Gap Conglomerate Member|Relationships and boundaries|The Member overlies the Temple Bar Sandstone with a local disconformity. On a regional scale this contact appears to be conformable. The Member is conformably overlain by the Blatherskite Sandstone Member.|16-MAY-23
6584|Fenn Gap Conglomerate Member|Age reasons|Upper Proterozoic (see reverse side Temple Bar SS Member).|16-MAY-23
6584|Fenn Gap Conglomerate Member|Proposed publication|Stewart & others (in preparation); Clarke in Wells, 1976 p.26)|16-MAY-23
6584|Fenn Gap Conglomerate Member|Defn Reference|80/20787|16-MAY-23
6584|Fenn Gap Conglomerate Member|Name first published by|Wells A.T., 1976|16-MAY-23
6584|Fenn Gap Conglomerate Member|Resdate|1970|16-MAY-23
24275|Fenton Granite|Name source|Fenton Airfield, a disused wartime airfield at AMG 530930, Tipperary 1:100 000.|16-MAY-23
24275|Fenton Granite|Unit history|Fenton Granite of Joplin (1957), Hurley and others (1961), Malone (1962), Walpole and others (1968), D'Addario and Pillinger (1985).|16-MAY-23
24275|Fenton Granite|Type section locality|A 2 km2 area of phase Pgfb some 5 km south of Plateau Point, aroung AMG 462892, Tipperary 1:100 000 sheet area (latitude 13o39'20"S, longitude 131o16'40"E).|16-MAY-23
24275|Fenton Granite|Extent|Two outcrop areas, one east of Plateau Point, the other west of Douglas homestead, together totalling some 120 km2 in northeastern Tipperary 1:100 000 Sheet area.|16-MAY-23
24275|Fenton Granite|Lithology|Three phases are recognised. Pgfa is a megacrystic foliated biotite-hornblende granite containing tabular perthitic microcline phenocrysts in a granular mass of anhedral biotite, hornblende, quartz, microcline and plagioclase. Accessory minerals are sphene, opaque minerals, zircon and apatite and rare epidote.  Pgfb is a medium- to coarse-grained granuloblastic to slightly porphyritic biotite granite with distinctive clear quartz crystals. Equal amounts of subhedral quartz and anhedral microcline occur as phenocrysts, or as equigranular crystals in the groundmass together with minor biotite and accessory hornblende, garnet, apatite and zircon. Biotite is commonly altered to sphene or chlorite.  Pgfc is a distinctively dark-coloured biotite-hornblende granite. The texture is sub- to anhedral granular, medium- to coarse-grained, of microcline, quartz, biotite and hornblende with some larger microcline and plagioclase laths up to 4 mm across. Hornblende and biotite are commonly altered to sphene, magnetite or epidote. Accessory minerals are apatite and zircon.|16-MAY-23
24275|Fenton Granite|Relationships and boundaries|All phases intrude the Mount Partridge Group, and Pgfb and Pgfc intrude the South Alligator Group (Early Proterozoic). Pgfa is faulted against Tolmer Group (Middle Proterozoic) and Jindare Formation (Early Cambrian), while Pgfb is faulted against South Alligator Group. All phases are overlain by Tindall Limestone (Middle Cambrian).|16-MAY-23
24275|Fenton Granite|Age reasons|Early Proterozoic. No isotopic dating available.|16-MAY-23
24275|Fenton Granite|Proposed publication|Tipperary 1:100 000 explanatory notes. NTGS.|16-MAY-23
24275|Fenton Granite|References|01/31584; 01/31583; GOLD1765; B082.|16-MAY-23
24275|Fenton Granite|Proposer|Whitehead B.R. (after Joplin, 1957)|16-MAY-23
72402|Ferdies Member|Name source|Ferdies Bore at (GDA94) 20deg34'S, 129deg23'E, THE GRANITES.|16-MAY-23
72402|Ferdies Member|Unit history|Mount Charles Beds (Blake et al 1975) in part, 'Lower Blake beds' (Smith et al 1998), MacFarlane Peak Group in part and Twigg Formation in part (Hendrickx et al 2000), basal 'Callie Formation' in Wygralak et al (2005).|16-MAY-23
72402|Ferdies Member|Geomorphic expression|Generally does not outcrop. Outcrops at northeastern McFarlane Peak Range are low and discontinuous; Officer Hill consists primarily of prominent Callie Member with subordinate Ferdies Member preserved.|16-MAY-23
72402|Ferdies Member|Type section locality|Magnetic quartzose psammite outcrops east of McFarlanes Peak Range at (GDA94) 20o18'00"S, 129o26'30"E, THE GRANITES.|16-MAY-23
72402|Ferdies Member|Type section locality|Outcrop of deformed feldspathic sandstone near Officer Hill at (GDA94) 20deg44'30''S, 129deg33'30''E, THE GRANITES in close association with Callie Member.|16-MAY-23
72402|Ferdies Member|Extent|Probably widely distributed throughout THE GRANITES and western two-thirds of TANAMI but outcrops poorly in comparison to overlying Callie Member of Dead Bullock Formation.|16-MAY-23
72402|Ferdies Member|Thickness range|Minimum 100 m thickness but likely to be significantly greater.|16-MAY-23
72402|Ferdies Member|Lithology|Sandy siltstone, siltstone, fine quartz sandstone and feldspathic sandstone, interbedded with shale and siltstone; occasional chert nodule-rich layers in siltstone; commonly contains magnetite.|16-MAY-23
72402|Ferdies Member|Depositional environment|Probable progression from shallow to deep marine (transgressive setting), with corresponding decrease in sediment supply.|16-MAY-23
72402|Ferdies Member|Relationships and boundaries|Inferred unconformity on gneissic or granitic basement, contact not observed. Uppermost fine arenite below siltstone and shale of Callie Member denotes top of Ferdies Member; contact corresponds with 865 m level of a composite drillcore log compiled by Lambeck (2004).|16-MAY-23
72402|Ferdies Member|Age reasons|Orosirian. Underlies Callie Member which has SHRIMP U-Pb zircon age of 1838+/- 4 Ma (Cross et al 2005). Detrital zircons in Ferdies Member suggest largely Archaean provenance; youngest detrital zircon population has age of 2.11 Ga (Cross et al 2005).|16-MAY-23
72402|Ferdies Member|Correlations|May be coeval with parts of lower Ooradidgee Group of Tennant Region and Lander Rock beds of Arunta Region. Cross et al (2005) suggested possible correlation with 1.91-1.88 Ga Saunders Creek Formation in Halls Creek Orogen.|16-MAY-23
72402|Ferdies Member|Proposed publication|Crispe AJ and Vandenberg LC, in press. Geology of the Tanami Region, Northern Territory. NTGS Report.|16-MAY-23
72402|Ferdies Member|Comments|Type and reference localities are the only known outcropping examples of Ferdies Member in THE GRANITES; not known to outcrop in TANAMI. One outcrop in MOUNT SOLITAIRE.Ferdies Member probably hosts dolerite of Groundrush deposit. Interlayered magnetite-bearing intervals impart a distinct aeromagnetic signature. Layer-parallel mafic intervals have been recognised from Groundrush deposit and in drillcore north of Rabbit Flat; these may represent coeval mafic volcanic rocks or dolerite sills.|16-MAY-23
72402|Ferdies Member|References|Blake DH, Hodgson IM and Muhling PC, 1975. The Granites, Northern Territory (First Edition). 1:250 000 geological series explanatory notes, SF 52-03. Northern Territory Geological Survey, Darwin.Cross AJ, Fletcher IR, Crispe AJ, Huston DL and Williams N, 2005. New constraints on the timing of deposition and mineralisation in the Tanami Group: in 'Annual Geoscience Exploration Seminar (AGES) 2004. Record of abstracts.' Northern Territory Geological Survey, Record 2004-001.Hendrickx MA, Slater KR, Crispe AJ, Dean AA, Vandenberg LC and Smith JB, 2000. Palaeoproterozoic stratigraphy of the Tanami Region: regional correlations and relation to mineralisation - preliminary results. Northern Territory Geological Survey, Record GS2000-13.Lambeck A, 2004. Sequence stratigraphic interpretation at Callie mine, Tanami Desert, Northern Territory. Geoscience Australia, Professional Opinion 2004/3.Smith MEH, Lovett DR, Pring PI and Sando BG, 1998. Dead Bullock Soak gold deposits: in Berkman DA and Mackenzie DH (editors) 'Australian and Papua New Guinean mineral deposits'. Australasian Institute of Mining and Metallurgy, Monograph 22, 449-460.Wygralak AS, Mernagh TP, Huston DL and Ahmad M, 2005. Gold mineral system of the Tanami Region. Northern Territory Geological Survey, Report 18.|16-MAY-23
72402|Ferdies Member|Proposer|Andrew Crispe, after Crispe and Vandenberg in Wygralak et al (2005).|16-MAY-23
6631|Fickling Group|Name source|That the Fickling Group now be extended to included the Fish River Formation. Former definition: The Fickling Group previously included only the Walford Dolomite, Mount Les Siltstone and Doomadgee Formation. Reasons for inclusion of Fish River Formation: The Fish River Formation, which unconformably overlies the Peters Creek Volcanics, marks the beginning of a major new cycle of sedimentation in the Westmoreland region of Queensland and adjacent parts of the Northern Territory. It is overlain conformably by the Walford Dolomite, which represents the beginning of widespread carbonate sedimentation after the initial clastic episode during transgression. The Fish River Formation had previously been excluded from the Fickling Group because it is not dolomitic. However, mapping of equivalent sequences in the Lawn Hill and Mount Isa areas show the same pattern of clastic, followed by dolomitic, sedimentation: ie, it is obviously a widespread sedimentation pattern, and the Fish River Formation is a part of it.|16-MAY-23
6631|Fickling Group|Name source|From Fickling Creek, a tributary of the Nicholson River in the southeastern part of the Nicholson River 1:100 000 Sheet area, Northern Territory (Sheet 6362).|16-MAY-23
6631|Fickling Group|Unit history|Mapped by Carter (1959) as Wollogorang Formation, a name now applied only to an older unit in the Tawallah Group in the McArthur Basin. Mapped by Roberts et al. (1963) as Fickling Beds. Name modified to Fickling Group as individual formations have now been recognised and named.|16-MAY-23
6631|Fickling Group|Constituents|Walford Dolomite, Mount Les Siltstone and Doomadgee Formation.|16-MAY-23
6631|Fickling Group|Extent|Exposed over an area of about 500 km2 in the southeastern Nicholson River, southeastern Seigal, southwestern Hedleys Creek, and northeastern Cleanskin 1:100 000 Sheet areas.|16-MAY-23
6631|Fickling Group|Thickness range|600-800 m.|16-MAY-23
6631|Fickling Group|Lithology|All units are predominantly shallow water sediments and contain dolomitic beds.|16-MAY-23
6631|Fickling Group|Relationships and boundaries|Conformable on Fish River Formation; overlain disconformably, and with angular unconformity, by the Constance Sandstone of the South Nicholson Group.|16-MAY-23
6631|Fickling Group|Age reasons|Proterozoic-Carpentarian.|16-MAY-23
6631|Fickling Group|Proposed publication|BMR Bulletin - Precambrian geology of the Westmoreland region, Northern Australia.|16-MAY-23
6631|Fickling Group|Proposed publication|BMR Report on geology of Hedleys Creek 1:100 000 Sheet area|16-MAY-23
6631|Fickling Group|Apprdate|24-JUN-1976|16-MAY-23
6631|Fickling Group|Apprdate|21-APR-1978|16-MAY-23
6631|Fickling Group|Defn approved by|Queensland Sub-Committee|16-MAY-23
6631|Fickling Group|Proposer|Sweet I.|16-MAY-23
6631|Fickling Group|State(s)|QLD|16-MAY-23
6631|Fickling Group|Status|1|16-MAY-23
6679|Fish Billabong Adamellite|Name source|Fish Billabong on the Daly River 1:100 000 sheet, AMG 750820|16-MAY-23
6679|Fish Billabong Adamellite|Unit history|Previously included in the Litchfield Complex (Walpole and others, 1968).|16-MAY-23
6679|Fish Billabong Adamellite|Type section locality|AMG 750705 (latitude 13o49'10", longitude 130o37'10"). Crops out as low, bouldery exposures on eluvial rises.|16-MAY-23
6679|Fish Billabong Adamellite|Extent|Outcrop covers about 40 km2 south of Fish Billabong.|16-MAY-23
6679|Fish Billabong Adamellite|Lithology|Varies from fine-through medium- to coarse-grained biotite adamellite, with poikilitic texture and minor myrmekite. Some aplite. Mineralogy: quartz, plagioclase, alkali feldspar and biotite; some quartz-adularia veins and rare fluorite.|16-MAY-23
6679|Fish Billabong Adamellite|Relationships and boundaries|Intrudes the Early Proterozoic Hermit Creek Metamorphics and Early Proterozoic Burrell Creek Formation (no contact exposed). Unconformably overlain by Early Cambrian sedimentary rocks and Antrim Plateau Volcanics.|16-MAY-23
6679|Fish Billabong Adamellite|Age reasons|Early Proterozoic. Undated, however the non-foliated texture and relationships (below) indicate that it is a probable late- to post-orogenic* intrusive, similar to others found in the Pine Creek Geosyncline and the Litchfield Block areas. (*1870 Ma - 1800 Ma orogeny in the Pine Creek Geosyncline (Needham and others, 1980).|16-MAY-23
6679|Fish Billabong Adamellite|Proposed publication|Explanatory Notes (for) Daly River (5070). Northern Territory Geological Survey 1:100 000 Geological Map Series. Northern Territory Government Printer, Darwin. Dundas D.L., Edgoose C.J., Fahey G.M., Fahey J.E. in prep.|16-MAY-23
6679|Fish Billabong Adamellite|Category|2|16-MAY-23
84109|Fish Hole Formation|Name source|Unit name derived from Fish Hole Creek, which joins Brunette Creek at approx. (GDA94) latitude 18°32’50”S longitude 136°13’06”E on the BRUNETTE DOWNS 1:250 000 mapsheet in the Northern Territory, and extends eastward into the MOUNT DRUMMOND 1:250 000 mapsheet. Fish Hole Creek rises at approximately (GDA94) latitude 18°33’14”S longitude 137°1’58”E in the MOUNT DRUMMOND 1:250 000 mapsheet area.|
84109|Fish Hole Formation|Unit history|Unit was originally mapped as an undivided part of the “Constance Sandstone” on the First Edition MOUNT DRUMMOND 1:250 000 mapsheet (Smith and Roberts, 1963a, b) and subsequently remapped as the “Playford Sandstone” on the Second Edition MOUNT DRUMMOND 1:250 000 mapsheet by Rawlings et al (2008). [Geochronology has shown the need to distinguish rocks in the hanging wall of the Mitchiebo-Maloney Fault, as a distinct, likely older unit than the rest of the Playford Formation.]|
84109|Fish Hole Formation|Geomorphic expression|Outcrops of low sandstone ridges with intervening valleys underlain by more fine-grained components.|
84109|Fish Hole Formation|Type section locality|There is no type locality nominated for this formation. A reference area is nominated in the western MOUNT DRUMMOND 1:250 000 mapsheet, in the vicinity of (GDA94) latitude 18°39’S longitude 136°46’E (53K 686350mE 7936980mN).|
84109|Fish Hole Formation|Extent|The Fish Hole Formation is exposed predominantly in the south western sector of the MOUNT DRUMMOND 1:250 000 mapsheet in the Northern Territory [north of the Mitchiebo-Maloney Fault].|
84109|Fish Hole Formation|Thickness range|Unit thickness is variable, but reaches in excess of 1450 m for the extent of former Playford Sandstone that has been redefined to the Fish Hole Formation (Rawlings et al, 2008).|
84109|Fish Hole Formation|Lithology|Waterfall Member (formerly the Wangalinji Member of the Playford Sandstone; Rawlings et al, 2008): Lower portions of member comprise white, thickly bedded, medium- to coarse-grained cross-bedded sandstone, with current ripples and lineations, mudstone intraclasts, and pebbly layers. Overlying upper portions of member comprise laminated shale with thinly bedded siltstone and very fine-grained lithic sandstone interbeds, interbedded with medium to thick beds of white, cross-bedded, sublithic, medium- to coarse-grained sandstone; some rare chert and carbonate rocks (Rawlings et al, 2008). Ten Mile Creek Member (formerly [included in] the Top Lily Sandstone Member of the Playford Sandstone) (Rawlings et al, 2008): White to pink/dark pink-red, thickly to very thickly bedded, very fine- to fine-grained, well-sorted lithic sandstone; scattered granules and pebbles, trough cross-bedded on large scale, current ripples and primary current lineations common (Rawlings et al, 2008).|
84109|Fish Hole Formation|Depositional environment|Shallow-marine shelf, mainly tide-dominated and nearshore, with some minor, more deep-water, storm-dominated facies (Rawlings et al, 2008).|
84109|Fish Hole Formation|Relationships and boundaries|The stratigraphic relationship between the Fish Hole Formation and the underlying units is not exposed. The Fish Hole Formation might unconformably overlie units of the Carrara Range Group. The Fish Hole Formation is conformably overlain by the Racecourse Formation (formerly the Crow Formation, McNamara Group).|06-OCT-23
84109|Fish Hole Formation|Identifying features|The lower Waterfall Member is quartzose, varies from very coarse-grained to granule-bearing, and has a distinctive white colour (Rawlings et al, 2008). The upper Ten Mile Creek Member is highly ferruginous and manganiferous in nature, and displays gossanous weathering crusts (Rawlings et al, 2008).|
84109|Fish Hole Formation|Age reasons|Maximum depositional age derived from U-Pb SHRIMP dating of detrital zircons: Wangalinji Member of the Playford Sandstone (stratigraphically overlies the Ten Mile Creek Member): GA Sample 2785614 - 1600 ± 20 Ma (Kositcin and Carson, 2019). Ten Mile Creek Member: GA sample 2786167 - 1656 ± 12 Ma (Kositcin and Carson, 2019). Ten Mile Creek Member: GA Sample 3305196 - 1641 ± 14 Ma (Kositcin et al, 2020). Drummond Formation of the Carrara Range Group (may stratigraphically underlie the Waterfall Member): GA Sample 2785617 - 1715 ± 30 Ma (Kositcin and Carson, 2019). Therefore, the potential depositional age range for the Fish Hole Sandstone can be considered to extend from ca. 1715±30 Ma to 1600±20 Ma.|
84109|Fish Hole Formation|Correlations|The Ten Mile Creek Member yielded similar maximum depositional ages to the ungrouped Caulfield Formation and several other formations of the McNamara Group, including the Shady Bore Quartzite, Bullrush Conglomerate and Plain Creek Formation (Kositcin and Carson, 2019). The Fish Hole Formation may be correlative with components of the upper Glyde package to the lowermost Favenc package (Rawlings, 1999) of the McArthur Basin.|06-OCT-23
84109|Fish Hole Formation|Geophysical Expression|Moderate to high magnetic response, due to the Fish Hole Sandstone including intervals containing ferruginous, very fine-grained sandstone, and hematitic siltstone to ironstone (Rawlings et al, 2008).|
84109|Fish Hole Formation|Defn author|Elliot Foley, Jack Simmons, Ben Williams, Charles Verdel (Northern Territory Geological Survey), Chris Carson (Geoscience Australia) 31-May-2023.|
84109|Fish Hole Formation|Comments|Note: All locations are based on the GDA94 geodetic datum. Standard series 1: 100 000 and 1: 250 000 mapsheet names are shown in uppercase.|
84109|Fish Hole Formation|References|Carson, C. J., Kositcin, N., Anderson, J. R., and Henson, P. A. in prep. A revised Proterozoic tectono-stratigraphy of the South Nicholson region, Northern Territory, Australia - insights from SHRIMP U-Pb detrital zircon geochronology. Australian Journal of Earth Sciences. 
 **Kositcin N and Carson CJ, 2019. New SHRIMP U-Pb zircon ages from the South Nicholson and Carrara Range regions, Northern Territory. Geoscience Australia, Record 2019/09.  **Kositcin N, Carson CJ, Anderson JR, Doublier MP and Murr J, 2020. Exploring for the Future - New SHRIMP geochronology constraints on the basin evolution of the South Nicholson region. Geoscience Australia, Record 2020/025.  **Rawlings DJ, 1999. Stratigraphic resolution of a multiphase intracratonic basin system: the McArthur Basin, northern Australia. Australian Journal of Earth Sciences 46(5), 703–723.  **Rawlings DJ, Sweet IP and Kruse PD, 2008. Mount Drummond, NT (Second Edition). 1:250 000 Geological Map Series Explanatory Notes, Sheet SE 53-12. Northern Territory Geological Survey, Darwin, Northern Territory.  **Simmons JM, Williams B, Carson, C and Verdel C, 2023a. Mount Drummond, Northern Territory 1:250 000 Geological Map, Sheet SE 53-12 (Third Edition). Northern Territory Geological Survey, Darwin, Northern Territory.  **Simmons JM, Williams B, Carson, C and Verdel C, 2023b. Mount Drummond, Northern Territory 1:250 000 Geological Map Explanatory Notes, Sheet SE 53-12 (Third Edition). Northern Territory Geological Survey, Darwin, Northern Territory.  **Smith JW and Roberts HG, 1963a. Mount Drummond, NT (First Edition). 1:250 000 Geological Map Series Explanatory Notes, Sheet 53-12. Bureau of Mineral Resources, Canberra.  **Smith JW and Roberts HG, 1963b. Mount Drummond, NT (First Edition). 1:250 000 Geological Map Series, Sheet SE 53-12. Bureau of Mineral Resources, Canberra.|
75722|Florina Formation|Name source|Florina pastoral lease [homestead: 14.453°S, 131.687°E (MGA94 Zone 52: 789730mE 8400660mN)].|16-MAY-23
75722|Florina Formation|Unit history|Previously identified as part of Jinduckin Formation and Oolloo Dolostone (eg Randal 1962, Jones 1971).|16-MAY-23
75722|Florina Formation|Geomorphic expression|Generally a recessive unit with limited exposures, mainly along Daly River banks and bed. Dolostone may form distinctive, small karstic towers. The bulk of the formation is covered by Cretaceous siliciclastic rocks. Exposures mainly restricted to Daly River and localised areas within 5 km of this watercourse. River exposures occur from junction with Katherine River, north to near junction with Bradshaw Creek. Isolated exposures occur north of Katherine River.|16-MAY-23
75722|Florina Formation|Type section locality|Type section is 17 km-long stretch of Daly and Katherine Rivers, downstream from 14.658862°S 131.709930°E,( MGA94 Zone 52: 791890mE 8377657mN; base) to 14.507198°S 131.676606°E (MGA94 Zone 52: 788496mE, 8394490mN; top); Fergusson River 1:250,000 mapsheet (SD 52-12), Bowman 1:100,000 mapsheet (5268). Section includes discontinuous, nearly flat-lying exposures of most but not all parts of succession; basal contact with Oolloo Dolostone is not exposed. Limited access via station tracks on Florina pastoral station, with best access by boat.  Reference section is in waterbore RN37043, air rotary drilled in 2010 by Northern Territory Department of Natural Resources, Environment, the Arts and Sport at 14.508413°S, 131.682907°E (MGA94 Zone 52: 789175mE, 8394342mN), accessible via station tracks on Florina pastoral lease. Section includes 167 m of Florina Formation overlying Oolloo Dolostone. Chip samples stored at Northern Territory Geological Survey Core Library, Darwin.|16-MAY-23
75722|Florina Formation|Description at type locality|Alternating dolostone, fine-grained glauconitic siliciclastic rocks and minor limestone. Siliciclastic intervals comprise 70% of type section and consist of distinctive yellow-brown to brown to maroon, glauconitic fine sandstone and minor shale. Carbonate intervals are distinctively bedded with decimetre-scale layering that forms benches; these are dominantly dolostone, but small areas of unaltered limestone occur.|16-MAY-23
75722|Florina Formation|Extent|Florina Formation occupies central part of Daly Basin, mostly in subsurface, and forms an elongated oval shape approximately 20 km by 70 km, with long axis trending northwest.|16-MAY-23
75722|Florina Formation|Thickness range|Impossible to estimate along type section due to very low and commonly undulating dip of beds, and discontinuous exposure. In waterbore RN37043 reference section, unit is 167 m thick and, in ascending order, comprises; dolostone 31.5 m, glauconitic sandstone 56 m, dolostone 20 m and glauconitic sandstone 59.5 m. An overlying dolostone interval at least 5 m thick outcrops in Daly River less than 1 km from reference section but is absent in borehole due to pre-Cretaceous erosion. Insufficient information available to determine thicknesses variations.|16-MAY-23
75722|Florina Formation|Depositional environment|Dominantly marine, peritidal mudflat to subtidal lagoonal.|16-MAY-23
75722|Florina Formation|Fossils|Undescribed trilobites, brachiopods, echinoderms, gastropods and hyoliths occur in middle and upper dolostone intervals. Trilobites and brachiopods from middle interval listed in Öpik (1968). Conodont fauna from middle dolostone interval listed in Jones (1971).|16-MAY-23
75722|Florina Formation|Diastems or hiatuses|None recognised.|16-MAY-23
75722|Florina Formation|Relationships and boundaries|In borehole RN37043 reference section, Florina Formation overlies karstified upper surface of King Member of Oolloo Dolostone; this relationship probably applies over entire extent of Florina Formation. Boundary in reference section marked by sharp change from coarsely crystalline, pink and cavernous dolostone below, to finely crystalline grey dolostone above. Bedding in both formations is essentially parallel but karstified surface indicates considerable time break. Contact has not been recognised in outcrop. Cretaceous sandstone, shale and claystone unconformably overlie Florina Formation. In type section, these directly overlie progressively younger parts of Florina Formation in downstream direction.|16-MAY-23
75722|Florina Formation|Identifying features|Glauconitic sandstone and well bedded grey carbonate intervals distinguish Florina Formation from other Daly Basin units. Overlying Cretaceous strata is softer and lacks carbonate rocks. Underlying King Member of Oolloo Dolostone is distinguished by its coarsely crystalline, massive pink dolostone.|16-MAY-23
75722|Florina Formation|Structure and Metamorphism|Flat-lying to near flat-lying. Unmetamorphosed.|16-MAY-23
75722|Florina Formation|Age reasons|Trilobites and brachiopods (Öpik 1968) and conodonts (Jones 1971) from a locality 4 km south southwest of Dorisvale Crossing of Daly River (Claravale area) dated as Early Ordovician (Tremadocian to Floian).|16-MAY-23
75722|Florina Formation|Correlations|Similar conodont fauna was reported by Jones (1971) from Ninmaroo Formation in southern Georgina Basin. Ninmaroo Formation interdigitates with Tomahawk Formation, a unit incorporating similarly distinctive quartz-glauconite sandstone. Possibly equivalent to poorly dated Hanson River beds of Wiso Basin.|16-MAY-23
75722|Florina Formation|Alteration and Mineralisation|None recorded.|16-MAY-23
75722|Florina Formation|Geophysical Expression|Down-hole gamma log signature is distinctive, with highly variable gamma counts in glauconitic sandstone and low counts in dolostone units.|16-MAY-23
75722|Florina Formation|Geochemistry|None available.|16-MAY-23
75722|Florina Formation|Defn author|Steven Tickell, Pierre Kruse and Tim Munson, 20 March 2015|16-MAY-23
75722|Florina Formation|Proposed publication|Defining publication: Tickell SJ, Kruse PD and Munson TJ, in prep. Revision of the Cambrian-Ordovician succession of the Daly Basin, Northern Territory. Australian Journal of Earth Sciences.|16-MAY-23
75722|Florina Formation|References|Kruse PD, Tickell SJ and Munson TJ, 2012. Florina Formation: a new Ordovician unit capping the Daly Basin succession, Northern Territory: in Ambrose GJ and Scott J (editors) 'Central Australian Basins Symposium (CABS) III'. Petroleum Exploration Society of Australia, Special Publication. **Jones PJ, 1971. Lower Ordovician conodonts from the Bonaparte Gulf Basin and the Daly River Basin, northwestern Australia. Bureau of Mineral Resources, Australia, Bulletin 117.**Opik AA, 1968. Early Ordovician at Claravale in the Fergusson River area, Northern Territory. Bureau of Mineral Resources, Australia, Bulletin 80, 163-165. **Randal MA, 1962. Fergusson River, Northern Territory (First Edition). 1:250 000 geological map series explanatory notes, SD 52-12. Bureau of Mineral Resources, Australia, Canberra. **Tickell SJ, 2010b Daly Basin Drilling, 2010. Water Resources Division, Northern Territory Department of Natural Resources Environment the Arts and Sport, Technical Report 24/2010.|16-MAY-23
24278|Fog Bay Metamorphics|Name source|Fog Bay; Fog Bay 1:100 000 Sheet 4972, Fog Bay 1:250 000 Sheet.|16-MAY-23
24278|Fog Bay Metamorphics|Unit history|Unit Pc of Hickey (1985); Fahey and Edgoose (1986); Pietsch (1986).|16-MAY-23
24278|Fog Bay Metamorphics|Type section locality|Represented in core from the following drill holes (Hole number, intersection and AMG co-ordinates are given): Pop 10 (75 m to 350 m), FL 588907; Pop 13 (59 m to 191 m), FL 583904; (Fog Bay 1:100 000 sheet area) both at approximately 12o44'42"S, 130o27'44"E. Holes drilled by Idemitsu Uranium Exploration Australia Pty Ltd, 1983. Core stored at Northern Territory Department of Mines and Energy Core Library, Darwin.|16-MAY-23
24278|Fog Bay Metamorphics|Extent|Eastern part of Fog Bay 1:100 000 Sheet and western part of Bynoe 1:100 000 Sheet. Unit is entirely subsurface, concealed by Mesozoic and Cainozoic sediments and intersected in 17 drillholes, as shown on Fog Bay 1:100 000 geological map sheet.|16-MAY-23
24278|Fog Bay Metamorphics|Thickness range|Unknown. Thickest core intersection is 275 m.|16-MAY-23
24278|Fog Bay Metamorphics|Lithology|Quartz-feldspar-biotite gneiss and schist commonly containing garnet and sillimanite; amphibolite; minor calc-silicate and marble.|16-MAY-23
24278|Fog Bay Metamorphics|Relationships and boundaries|Correlation with other Early Proterozoic units has not been made. Faulted against both Welltree Metamorphics and Two Sisters Granite to the east by Tom Turners Fault. Faulted to the west and south against Wagait Granite, dated at 1850 Ma. Northern extension obscured by Mesozoic sediments.|16-MAY-23
24278|Fog Bay Metamorphics|Age reasons|Early Proterozoic as: 1. Age of crustal formation of original components is 2280 40 Ma (Hickey, 1985).  2. Unit metamorphosed at 2002 42 Ma (Hickey, 1985).|16-MAY-23
24278|Fog Bay Metamorphics|Comments|Reserved, updated to YE 24/4/88|16-MAY-23
24278|Fog Bay Metamorphics|Category|2|16-MAY-23
24278|Fog Bay Metamorphics|Proposer|Pietsch B.A.|16-MAY-23
29775|Forty Five Augen Gneiss|Name source|45 Bore, Narwietooma Pastoral Lease.|16-MAY-23
29775|Forty Five Augen Gneiss|Unit history|Previously included in Redbank Hill porphyroblastic gneiss (informal, Glikson, 1984).|16-MAY-23
29775|Forty Five Augen Gneiss|Geomorphic expression|Rough boulder-strewn hill slopes.|16-MAY-23
29775|Forty Five Augen Gneiss|Type section locality|Southwestern part of Redbank Hill near GR 267600 7408900, Narwietooma 1:100 000 Sheet area.|16-MAY-23
29775|Forty Five Augen Gneiss|Extent|Southern part of the Redbank Hill massif.|16-MAY-23
29775|Forty Five Augen Gneiss|Lithology|Augen gneiss, mylonitic gneiss, granitic gneiss, microgranite.|16-MAY-23
29775|Forty Five Augen Gneiss|Relationships and boundaries|Intrudes Bunghara Metamorphics.|16-MAY-23
29775|Forty Five Augen Gneiss|Structure and Metamorphism|Includes phases that are both syn and post-tectonic with the Strangways Orogeny at 1760-1750 Ma. Also partly converted to Mylonite during Anmatjira Uplift Phase at about 1450 (Black and Shaw, 1992; Shaw and Black, 1991).|16-MAY-23
29775|Forty Five Augen Gneiss|Age reasons|1760 Ma (ion-microprobe of zircon, Black & Shaw, 1992).|16-MAY-23
29775|Forty Five Augen Gneiss|Defn author|R.D. Shaw & R.G. Warren, 3 July 1991.|16-MAY-23
29775|Forty Five Augen Gneiss|Comments|This 'definition' is missing the details of references mentioned in the synonymy and age, and shows no signs on the card of having been approved.|16-MAY-23
33651|Foster Cliff Granite|Name source|Foster Cliff, 25o35'8.9"S, 130o25'40"E, Petermann Ranges.|16-MAY-23
33651|Foster Cliff Granite|Unit history|Comprises part of the Olia Gneiss and unnamed metamorphosed granites of Forman (1966, 1972).|16-MAY-23
33651|Foster Cliff Granite|Constituents|Nill. Forms part of the Mantarurr Granite Suite.|16-MAY-23
33651|Foster Cliff Granite|Geomorphic expression|Low outcrops and rounded rocky hills. Rubbly slopes underlying quartzite scarps of Foster Cliff region and Butler Dome.|16-MAY-23
33651|Foster Cliff Granite|Type section locality|1.5 km west of Foster Cliff 25o35'9.6"S, 130o24'39.2"E.|16-MAY-23
33651|Foster Cliff Granite|Extent|Occurs extensively throughout Olia Chain, particularly in regions up to 10 km west and south of Stevenson Peak, in the vicinity of Foster Cliff and extending 10-15 km southwest of Foster Cliff and a 4 x 4 km region centred 6 km northeast of Butler Dome, Petermann Rangeas.|16-MAY-23
33651|Foster Cliff Granite|Lithology|Foliated biotite granite which is typically finely porphyritic with abundant small phenocrysts of K-feldspar 2-5 mm in diameter. Locally the granite is equigranular and fine to medium grained. The mineralogy typically comprises quartz, K-feldspar, plagioclase, biotite, sphene, ilmenite and epidote, with secondary muscovite and accessory allanite. This granite is locally intruded by fine to medium grained leucogranites, and leucocratic veins and pegmatites.|16-MAY-23
33651|Foster Cliff Granite|Relationships and boundaries|Has contacts with the Kulu Granite which range from being sharp and intrusive to being apparently gradational. Has sharp intrusive contacts with the Utanta and Wala Wuru Granites. No consistent timing relationships are evident, although the presence of a diffuse early fabaric suggests that this may be the oldest granite in the Mantarurr Granite Suite. Is intruded by mafic dykes of the 800 Ma Amata Dyke Swarm and possibly also the 1078 Ma Alcurra Dyke Swarm.|16-MAY-23
33651|Foster Cliff Granite|Age reasons|Mesoproterozoic. Correlated (on the basis of geochemical similarities) with Kulu Granite which has a SHRIMP U-Pb zircon age of c.1168 +/- 14 Ma (M Fanning, pers. comm.)|16-MAY-23
33651|Foster Cliff Granite|Correlations|Geochemically and mineralogically similar to the Utanta Granite, Wala Wuru Granite and Kulu Granite. Similar age, but geochemically distinct from the Pottoyu and Umutju Granite Suites and Walal Granite on Petermann Ranges.|16-MAY-23
33651|Foster Cliff Granite|Proposed publication|Petermann Ranges 1:250 000 geological mapsheet Explanatory Notes.|16-MAY-23
33651|Foster Cliff Granite|Comments|Deformed and metamorphosed at 5-6 kbars and ~600-650oC during the c.560 Ma Petermann Orogeny.|16-MAY-23
33651|Foster Cliff Granite|Category|2|16-MAY-23
33651|Foster Cliff Granite|Defn approved by|Beier P., Kruse P.D., Young D.N.|16-MAY-23
33651|Foster Cliff Granite|Proposer|Edgoose C.J., Close D.F., Scrimgeour I.R.|16-MAY-23
80343|Fosters Suite|Name source|After Fosters Bore (632970mE 7485970mN, GDA94, Zone53) in Jervois Range 1:100 000 mapsheet, Northern Territory.|16-MAY-23
80343|Fosters Suite|Geomorphic expression|Generally poorly exposed, scattered outcrops; irregular, sharp-crested and rubbly hills; low bouldery outcrops in lowlands.|16-MAY-23
80343|Fosters Suite|Type section locality|There is no single locality where all constituent units are exposed. See definition cards for description of constituent units.|16-MAY-23
80343|Fosters Suite|Extent|Constituent units sporadically outcrop in the western and central area of the Jervois Range 1:100 000 mapsheet, north of the Marshall River and south and southeast of the Johannsen and Jervois ranges (between 7473000mN-7503000mN and 595000mE-657000mE, GDA94, Zone 53).|16-MAY-23
80343|Fosters Suite|General description|Constituent units are mica-bearing leucogranites. All constituent units are deformed by a regional main foliation. Locally contains xenoliths of Bonya Metamorphics and Kings Legend Metadolerite. Interpreted to intrude White Violet and Mascotte orthogneisses. Intruded by Boundary Igneous Complex and Samarkand Pegmatite. Locally unconformably overlain by Oorabra Arkose and Grant Bluff Formation of the Georgina Basin; locally faulted contacts with various units of the Georgina Basin.|16-MAY-23
80343|Fosters Suite|Depositional environment|Continental margin environment, either arc cordillera or back arc basin, or derived from melting of pre-existing crust that formed in a continental margin environment.|16-MAY-23
80343|Fosters Suite|Structure and Metamorphism|All constituent units are overprinted by the regional main foliation ranging from weakly to strongly foliated and locally gneissic; locally overprinted by mylonitic foliation along and adjacent to fault zones; all constituent units deformed during regional high-thermal gradient amphibolite facies metamorphism but metamorphic overprint is not always apparent.|16-MAY-23
80343|Fosters Suite|Age reasons|Crystallisation age of suite is based on LA-ICP-MS 207Pb/206Pb zircon age of 1780 ± 4 Ma for the Jericho Granite (Beyer et al in prep).|16-MAY-23
80343|Fosters Suite|Correlations|Interpreted as co-magmatic and co-genetic with the Casper Suite and Mascotte Orthogneiss of the Baikal Supersuite based on similar geochemical and isotopic composition, and timing of structural fabric development.|16-MAY-23
80343|Fosters Suite|Alteration and Mineralisation|Local K-feldspar-quartz alteration, hematitisation, silicification and brecciation, quartz and calcite veining is common close to shear zones; no known mineralisation.|16-MAY-23
80343|Fosters Suite|Geophysical Expression|When extensive enough the constituent units are characterised by magnetic-low signals, often with a magnetic-high contact aureole; no clear gravity signal; radiometric high signal.|16-MAY-23
80343|Fosters Suite|Geochemistry|I-type intrusives; dominantly peraluminous and less commonly metaluminous compositions, high-K to shoshonitic compositions, enriched in LREE compared to HREE, well-developed negative Eu anomalies, juvenile to evolved Nd isotopic signatures.|16-MAY-23
80343|Fosters Suite|Defn author|Anett Weisheit, Barry Reno, Eloise Beyer (Northern Territory Geological Survey) 01-MAY-2018.|16-MAY-23
80343|Fosters Suite|Proposed publication|Weisheit A, Reno BL and Beyer EE, in review. Jervois Range Special, Northern Territory. 1:100 000 geological map explanatory notes, 6152 and part 6252. Northern Territory Geological Survey, Darwin.|16-MAY-23
80343|Fosters Suite|References|Beyer EE, Reno BL, Weisheit A, Meffre S, Thompson J and Woodhead JD, in prep. Summary of results. NTGS laser ablation ICP-MS U-Pb-Hf geochronology project: selected samples from Jinka and Jervois Range 1:100 000 mapsheets, Aileron and Irindina Provinces, Arunta Region, January 2016-December 2017. Northern Territory Geological Survey, Darwin.|16-MAY-23
83012|Francis Dam Granodiorite|Name source|Named after Francis Dam (GDA94, 53K, 583876mE, 7873683mN), approximately 38 km northwest of the type intersection of this unit in drill hole NDIBK09.|16-MAY-23
83012|Francis Dam Granodiorite|Geomorphic expression|No known outcrops.|16-MAY-23
83012|Francis Dam Granodiorite|Type section locality|Drill hole NDIBK09, down-hole depth from 161.58 m to 166.91 m. Drillhole location 608328 mE 7843609 mN (MGA94 zone 53) / 19.499208S 136.032320E. Drill core is stored at the NTGS core library in Alice Springs.|16-MAY-23
83012|Francis Dam Granodiorite|Description at type locality|Medium- to coarse-grained granodiorite comprising plagioclase, potassium feldspar, quartz and minor weakly oriented biotite, white mica and hornblende, with traces of apatite, zircon, titanite and rutile.|16-MAY-23
83012|Francis Dam Granodiorite|Extent|Poorly defined. Clark et al. (2021) interpreted this unit to extend within a ~10 km diameter area defined by a chaotic, or disrupted texture, in magnetics imagery and a subtle gravity low. However, a lack of distinctive geophysical properties relative to the surrounding rocks of the Alroy Formation, together with complexities due to overlying magnetic rocks of the Kalkarindji Suite, result in a unit that is extremely difficult to map undercover.|16-MAY-23
83012|Francis Dam Granodiorite|General description|This unit is only known from drillhole NDIBK09, where it is intersected numerous times. These intersections do not differ significantly in appearance from the type intersection described above.|16-MAY-23
83012|Francis Dam Granodiorite|Thickness range|The type section of this unit has a maximum thickness of only 5.5 m. However, the unit comprises around 90% of the ca. 200 m basement intersection of drill core NDIBK09.|16-MAY-23
83012|Francis Dam Granodiorite|Lithology|Medium- to coarse-grained granodiorite comprising plagioclase, potassium feldspar, quartz and minor weakly oriented biotite, white mica and hornblende, with traces of apatite, zircon, titanite and rutile.|16-MAY-23
83012|Francis Dam Granodiorite|Relationships and boundaries|The type intersection of this unit is bounded by intrusive rocks of the Quart Pot Granite. The Quart Pot Granite intrudes the Francis Dam Granodiorite.|16-MAY-23
83012|Francis Dam Granodiorite|Identifying features|More equigranular and older than the Quart Pot Granite, which makes up the only other known basement stratigraphy in the immediate vicinity of the type intersection of the Francis Dam Granodiorite.|16-MAY-23
83012|Francis Dam Granodiorite|Structure and Metamorphism|In thin sections of the limited drill core available, this unit appears largely undeformed, with the exception of minor faulting and related vein formation. A weak foliation may reflect either magmatic or solid-state processes. In regional geophysical imagery, magnetic lineaments in the Alroy Formation wrap the interpreted extent of this unit, suggesting that magmatic emplacement predated some ductile deformation (Clark et al., 2021).|16-MAY-23
83012|Francis Dam Granodiorite|Age reasons|SHRIMP U-Pb analysis of this rock indicates that it was emplaced at 1846.1 +/- 4.8 Ma (Kositcin and Cross et al., in prep). A minimum age constraint is also provided by cross-cutting rocks of the Quart Pot Granite (1839.9 +/-3.8 Ma). (Kositcin and Cross et al., in prep).|16-MAY-23
83012|Francis Dam Granodiorite|Alteration and Mineralisation|The unit has been affected by minor chlorite, calcite and white mica alteration.|16-MAY-23
83012|Francis Dam Granodiorite|Geophysical Expression|Very subtle. Appears to be characterised by a disrupted magnetic signature in regional magnetics imagery, and less dense than the surrounding Alroy Formation.|16-MAY-23
83012|Francis Dam Granodiorite|Geochemistry|Based on limited data, the Francis Dam Granodiorite has a restricted, felsic compositional range (SiO2 = 72.2?74.1 wt.%). Like other constituents of the Mount Lamb Suite, it is high-K (K2O > 4.89 wt.%), peraluminous (ASI = 1.11?1.26) and enrichment of light rare earth elements relative to medium and heavy rare earth elements (normallised La/Yb = 10?31) with relatively flat medium to heavy rare earth elements (normalised Gd/Yb = 1.36?3.03), and a pronounced negative Eu anomaly (Eu/Eu* = 0.38?0.68). Evolved whole rock Nd isotopic composition from a single sample (epsilonNd 1846.1 Ma = -5.55).|16-MAY-23
83012|Francis Dam Granodiorite|Defn author|A.D. Clark  24- MAR-2022.|16-MAY-23
83012|Francis Dam Granodiorite|Proposed publication|Schofield and Clark et al., (in prep). Geology of the East Tennant area, Northern Territory, journal publication.|16-MAY-23
83012|Francis Dam Granodiorite|Comments|Geochemical characteristics and presence of hornblende suggest an I-type affinity, although this is somewhat at odds with peraluminous bulk rock composition.|16-MAY-23
83012|Francis Dam Granodiorite|References|Kositcin, N., Cross A.J., et al., in prep. Geochronology of the East Tennant area, Geoscience Australia record.  **Clark, A., Highet, L., Schofield, A., Doublier, M., 2021. Solid Geology map of the East Tennant region, dataset, Geoscience Australia.|16-MAY-23
24280|Frew River Formation|Name source|Frew River, the main watercourse in the western part of the Hatches 1:100 000 Sheet area, Frew River 1:250 000 Sheet area.|16-MAY-23
24280|Frew River Formation|Type section locality|Along small creek 5 km northwest of Errolola Rockhole (latitude 20o58'35"S, longitude 135o02'25"E) in Hatches 1:100 000 Sheet area; from GR 008834, where the formation overlies Coulters Sandstone (gradational conformable contact, taken at foot of ridge formed of Coulters Sandstone) north to GR 011838, where the formation is overlain abruptly by basaltic lava of the Kudinga Basalt. In this section the formation is about 500 m thick, dips 50-60o north, and consists of about 50 m of generally recessive thinly bedded quartzose, feldspathic, and kaolinitic arenites and micaceous siltstone, which show ripple marks, mud-cracks, and rare halite casts, and an overlying sequence about 450 m thick of mainly carbonates - yellow, brown, and pink stromatolitic dolomite and ripple-marked dolomitic arenite, and grey limey beds. The stromatolites present include bulbous forms about 50 cm across, algal mats, and Conophyron.|16-MAY-23
24280|Frew River Formation|Extent|Central and southern parts of the Davenport Province - central part of Bonney Well, southwestern part of Frew River, northwestern part of Elkedra, and northeastern part of Barrow Creek 1:250 000 Sheet areas.|16-MAY-23
24280|Frew River Formation|Thickness range|0 to 500 m.|16-MAY-23
24280|Frew River Formation|Lithology|Recessive thinly bedded fine-grained kaolinitic arenite, micaceous siltstone, and mudstone which in the upper part of the formation are commonly dolomitic and/or calcareous; laminated and stromatolitic dolomite and silty dolomite; subordinate quartz arenite and feldspathic quartz arenite, mainly near base.|16-MAY-23
24280|Frew River Formation|Relationships and boundaries|Conformable on Coulters Sandstone, overlain conformably by Kudinga Basalt.|16-MAY-23
24280|Frew River Formation|Age reasons|Younger than 1870 m.y. - U-Pb zircon age for volcanics within the Warramunga Group, which is overlain unconformably by the Hatches Creek Group.  Older than 1640 m.y. - Rb-Sr whole-rock age of granite intruding the Hatches Creek Group.|16-MAY-23
24280|Frew River Formation|Comments|Remarks: Distinctive recessive, partly calcareous formation within the Wauchope Subgroup of the Hatches Creek Group.|16-MAY-23
24280|Frew River Formation|Defn Reference|86/25362|16-MAY-23
24280|Frew River Formation|Proposer|Blake D.H., Stewart A.J., Sweet I.P.|16-MAY-23
24280|Frew River Formation|Resdate|07-OCT-1981|16-MAY-23
79774|Froud Formation|Name source|Froud Creek in southeastern HENBURY 1:250 000 mapsheet. Froud Creek joins the Finke River at 133.4107deg E,  -24.7698deg S.|16-MAY-23
79774|Froud Formation|Unit history|Part of the former Winnall beds of Ranford et al (1965).|16-MAY-23
79774|Froud Formation|Geomorphic expression|Forms low hills and strike ridges.|16-MAY-23
79774|Froud Formation|Type section locality|GDA94 53J 286499mE 7276995mN (132.8919deg E,  -24.6039deg S) (lower contact) to GDA94 53J 285973mE 7276891mN (132.8860deg E, -24.6073deg S) (upper contact) situated immediately south of Dead Bullock Plain.  Reference Locality: GDA94 53J 331094mE 7256130mN (133.3290deg E,  -24.8003deg S)(base) to GDA94 53J 331449mE 7255587mN (133.3246deg E,  -24.8052deg S) in a range of hills paralleling the southern bank of the east-flowing Froud River.|01-JUN-23
79774|Froud Formation|Extent|Currently mapped in eastern HENBURY 1:250 000 mapsheet, likely extends into RODINGA (and possibly FINKE) 1:250 000 mapsheets.|16-MAY-23
79774|Froud Formation|General description|Laterally variable as described in other parts of this definition.|16-MAY-23
79774|Froud Formation|Thickness range|Thickens from 65 m in central HENBURY 1:250 000 mapsheet to >165 m in eastern HENBURY. Apparently, very thin or absent in western HENBURY. Approximately 65 m at type locality; and (2) at least 165 m (incomplete) at reference locality. To east, Froud Formation thickens, whereas Gloaming and Liddle formations apparently thin.|16-MAY-23
79774|Froud Formation|Lithology|Type locality (1)Thinly-bedded, grain-size-laminated sandstone becoming very thinly bedded and fissile with a good parting up-succession, where it is also locally interbedded with more medium-bedded, medium-grained and less well-sorted and well-rounded quartz arenite transitional to overlying Liddle Formation. Typically, fine- to medium-grained well-sorted and well-rounded quartz arenite and felspathic quartz arenite, showing grain-size lamination. The sandstone generally becomes increasingly finer-grained and more well-sorted and well-rounded up succession (but note medium-grained interbeds described above).  Reference locality (2) In the east, the Froud Formation thickens while the Gloaming and Liddle formations apparently thin. In the refernce locality, Froud Formation remains a mature, winnowed quartz arenite with well-developed parting lineation. It comprises thinly planar-bedded, internally laminated, flaggy to fissile medium-grained quartz arenite. Near base of the unit (as exposed), sandstones are intensely ferruginised, iron-oxide-rich, pale-coloured and interlayered on a 2-3 m-scale. Subordinate to rare interbeds of medium-bedded quartz arenite have alternating red-brown and pale-grey lamination. Basal sandstones also locally show low-angle 3-4 metre-scale trough cross-beds. Up-succession sandstone is locally ripple-marked with desiccation features and abundant weathered-out shale clasts; and is white and locally silicified or with pale orange/brown weathering. Towards top, quartz arenite becomes fine-grained, but remains well-sorted and well-rounded, and is medium to thickly-bedded with bi-directional cross-strata. Sandstones at top of the exposed succession are interlayered very thinly-, planar-bedded and medium- to thickly-bedded cross-stratified quartz arenite. All up-succession changes are gradual and transitional. Uppermost, interlayered, thinly-, planar bedded and medium- to thickly bedded and cross-stratified sandstones may be transitional to Liddle Formation although this formation is not exposed at reference locality.|16-MAY-23
79774|Froud Formation|Depositional environment|Inferred to be off-shore on the basis of the paucity of shallow-marine to intertidal sedimentary structures that characterise the underlying and partially laterally equivalent Breaden Formation.|16-MAY-23
79774|Froud Formation|Diastems or hiatuses|No substantial features observed.|16-MAY-23
79774|Froud Formation|Relationships and boundaries|Transitional lower and upper contacts with Gloaming and Liddle formations respectively. At type locality, thinly interbedded quartz arenite and vuggy-weathering arkose are indicative of a transitional contact with underlying Gloaming Formation. This is expressed as a progressive change in sandstone maturity from less to more mature, and an interlayering of less and more mature sandstone. Approximately 15 m of recessive siltstone, included in Froud Formation, occur between these interbedded sandstones and typical Gloaming Formation. Froud Formation sandstone is generally more mature than Gloaming Formation. There are very few moulds after weathered-out shale clasts. Elsewhere, shale clasts are locally common in Froud Formation. At type locality, medium beds of medium-grained quartz arenite within the very thinly-, to thinly-bedded sandstones and an interlayering of fine- and medium-grained, and less- and more- well-rounded and well-sorted sandstone are indicative of transition to overlying Liddle Formation.|16-MAY-23
79774|Froud Formation|Identifying features|Distinguished from underlying Gloaming Formation by greater sandstone maturity, ie quartz arenite and felspathic-quartz arenite as opposed to arkose; and by grey, or grey-green colour, as opposed to dark red-brown/chocolate brown of Gloaming Formation. Froud Formation also largely lacks wide range of sedimentary structures that typify Gloaming Formation. Froud Formation is generally more thinly-bedded than lower Liddle Formation, which is also distinuished by its orangy-red weathering and more massive outcrop characteristics.|16-MAY-23
79774|Froud Formation|Structure and Metamorphism|Folded and faulted, but apparently unmetamorphosed.|16-MAY-23
79774|Froud Formation|Age reasons|Inferred to be latest Neoproterozoic (to early Cambrian?) on the basis that it is locally laterally equivalent to Gloaming and Liddle formations which are respectively considered to correlate with Pertatataka Formation and Arumbera Sandstone.|16-MAY-23
79774|Froud Formation|Correlations|A discrete stratigraphic unit between Gloaming and Liddle formations in the west, but apparently a lateral equivalent of both these units further east where it thickens and partially or completely replaces them. Correlated in part with Pertatataka Formation and Arumbera Sandstone.|16-MAY-23
79774|Froud Formation|Geophysical Expression|Generally linear, low Total Magnetic Intensity as is typical of Winnall Group.|16-MAY-23
79774|Froud Formation|Defn author|N Donnellan, VJ Normington, FEB 2017.|16-MAY-23
79774|Froud Formation|References|Ranford LC, Cook PJ and Wells AT, 1965. The geology of the central part of the Amadeus Basin, Northern Territory. Bureau of Mineral Resources, Australia, Report 86.|16-MAY-23
21824|Gadabara Volcanics|Name source|Gadabara District, an aboriginal clan ara to the north of Grindall Point in the northeastern part of Blue Mud Bay 1:250 000 scale mapsheet area.|16-MAY-23
21824|Gadabara Volcanics|Unit history|Previously undifferentiated "Bickerton Volcanics" of Plumb and Roberts (1965).|16-MAY-23
21824|Gadabara Volcanics|Geomorphic expression|Outcrop is relatively resistant and comprises blocks, boulders and rubble.|16-MAY-23
21824|Gadabara Volcanics|Type section locality|At the southern tip of Round Hill Island (latitude 13o19'S, longitude 136o6'E; AMG PF181269). No specific section is nominated due to lateral variation in rocktypes. Lower boundary stratotype at AMG PF173284 (Blue Mud Bay) where volcanic breccia of Gadabara Volcanics overlies migmatitic gneisses of the Bradshaw Complex. The boundary with the overlying Coast Range Sandstone is not well exposed, and a top boundary stratotype is not defined.|16-MAY-23
21824|Gadabara Volcanics|Extent|Outcrop is confined to Round Hill Island, adjacent to Grindall Point in the northeastern part of Blue mud Bay 1:250 000 scale mapsheet area.|16-MAY-23
21824|Gadabara Volcanics|Thickness range|Approximately 50 m at type locality.|16-MAY-23
21824|Gadabara Volcanics|Lithology|Salmon pink, but sometimes orange or brown, altered felsic igneous rock (rhyolite?). About half of the exposure is made up of coherent pink rock, the other half by volcanic breccia. Coherent rock, which takes the form of dykes, sills and lava flows, is generally microcrystalline and aphyric to slightly porphyritic (small K-feldspar), with accessory fragments of sandstone and granite, and locally common amygdales. Abundant thin (<1 m) banded dykes intrude the Bradshaw Complex on the western side of the island (lower boundary stratotype), and the volcanic breccia on the other sides of the island. Lava flows locally exhibit contorted flow banding, which appears to dip steeply away from the centre of the island, the inferred pre-existing volcanic edifice. They also contain occasional large rafts of contorted sandstone, presumably derived from the underlying Woodah Sandstone. Volcanic breccia, which tends to underlie or is intruded by the coherent rock, ranges from fine-grained volcanic sandstone to block and boulder volcanic breccia. Clasts are almost exclusively angular- or pillow-shaped pink-orange rhyolite as described above, with a variable component of clasts derived from the basement. Mud-grade volcaniclastic material makes up the matrix. These breccias range from crudely stratified to unstratified.|16-MAY-23
21824|Gadabara Volcanics|Depositional environment|Volcanic and shallow intrusive igneous rocks associated with probable subaqueous volcaniclastic rocks.|16-MAY-23
21824|Gadabara Volcanics|Relationships and boundaries|Intrudes and overlies the Bradshaw Complex and Woodah Sandstone and is in turn overlain unconformably by the Coast Range Sandstone.|16-MAY-23
21824|Gadabara Volcanics|Age reasons|Palaeoproterozoic (Statherian). Not well constrained. They appear to intrude and lie stratigraphically above the Woodah Sandstone, indicating they are probably younger than the ~1810 Ma Bickerton Rhyolite to the south (Pietsch and others, in prep.). The unconformably overlying Coast Range Sandstone is tentatively correlated with the Parsons Range Group (Haines and others, in prep.), which has a minimum age of ~1640 Ma (the age of the overlying McArthur Group in the south; Haines, 1994). They are similar to the ~1710 Ma Yanungbi Volcanics in Arnhem Bay (Rawlings and others, in prep.), and occupy a similar stratigraphic position.|16-MAY-23
21824|Gadabara Volcanics|Correlations|Possibly the Yanungbi Volcanics (Arnhem Bay) and Fagan Volcanics (Arnhem Bay and Blue Mud Bay mapsheet areas). This is based on similar stratigraphic position and petrology (Rawlings and othes, in prep.; Rawlings, 1994).|16-MAY-23
21824|Gadabara Volcanics|Proposed publication|Blue Mud Bay 1:250 000 Geological Map Series, Northern Territory, National Geoscience Mapping Accord, Explanatory Notes (Haines and others, in prep.).|16-MAY-23
21824|Gadabara Volcanics|Comments|Outcrop now assigned to this formation was previously (Plumb and jDunet, 1965) mapped as "Bickerton Volcanics", formalised by Plumb and Roberts (1992). Pietsch and others (in prep.) were able to demonstrate that the various outcrops assigned to this formation are non-correlatives, and in many cases are significantly different in age. The name was subsequently abandoned by Pietsch and others (in prep.) and the various outcrops were remapped as a series of new formations, including the Gadabara Volcanics.|16-MAY-23
21824|Gadabara Volcanics|Category|2|16-MAY-23
21824|Gadabara Volcanics|Defn approved by|Brakel A.T., Haines P.W.|16-MAY-23
21824|Gadabara Volcanics|Proposer|Rawlings D.J.|16-MAY-23
21824|Gadabara Volcanics|Reserved? Yes/No|Yes|16-MAY-23
34083|Gali Member|Name source|From Gali Outstation, a small settlement on the banks of Badalngarrmirri Creek, lat. 12o44'36"S, long. 135o26'19"E, Mirrngadja 1:100 000 sheet (5972).|16-MAY-23
34083|Gali Member|Unit history|The Gali Member was not distinguished during previous mapping of the Parsons Range Group by Plumb & Roberts (1992).|16-MAY-23
34083|Gali Member|Geomorphic expression|Recessive relative to the quartz arenite members above and below, and therefore a narrow valley, but the upper part of the member forms rounded low hills as a result of the resistant clayey sandstone interbeds.|16-MAY-23
34083|Gali Member|Type section locality|16.5 km northeast of Mount Fleming, the base is at lat. 13o17'15"S, long. 135o29'45"E; the top is at lat. 13o17'32"S, long. 135o29'48"?E.|16-MAY-23
34083|Gali Member|Extent|Main outcrops lie within the Parsons Range, extending from 3km south of the headwaters of Matta Murta Creek in the eastern Parsons Range, in an arcuate belt 50 km west, southwest and south, to a point about 17 km south-southeast of Mount Fawcett (Fleming 1:100 000 sheet); only other outcrops are in the valley in which Gali Oustation lies (Mirrngadja 1:100 000 sheet).|16-MAY-23
34083|Gali Member|Thickness range|Maximum of 360 m in eastern Parsons Range, including at type section, thinning to 0 m in the southwest.|16-MAY-23
34083|Gali Member|Lithology|Laminated to thin- and wavily-bedded, and hummocky cross-stratified mudstone and fine to coarse siltstone; interbeds of thin to medium bedded, fine-grained clayey sandstone in the upper part.|16-MAY-23
34083|Gali Member|Depositional environment|Storm-dominated shelf: lower to upper shoreface.|16-MAY-23
34083|Gali Member|Relationships and boundaries|A member of the Badalngarrmirri Formation, Parsons Range Group. Lower contact is marked by an abrupt change from quartz arenite below, to mudstone. It is a sharp contact, but is presumed conformable. The upper contact is probably gradational, with interfingering relationship of the clayey sandstone beds with quartz arenite. The upper boundary is placed at the first resistant medium-grained quartz arenite bed.|16-MAY-23
34083|Gali Member|Age reasons|Palaeoproterozoic: As for the parent formation, the maximum age of the member is well constrained by the age of the uppermost formation of the Donydji Group, the Fagan Volcanics, at 1710 Ma; minimum age is less well constrained, but must be greater than 1620 Ma, the age of the Yarrawirrie Formation in the overlying Balma Group (Pietsch and others, 1994), and most likely older than 1640 Ma, the age of the Barney Creek Formation (Page & Sweet, in press), a correlative of the central Balma Group (Haines, 1994).|16-MAY-23
34083|Gali Member|Correlations|No known correlatives.|16-MAY-23
34083|Gali Member|References|HAINES, P.W., 1994 - The Balma and Habgood Groups, Northern McArthur Basin, Northern Territory: stratigraphy and correlations with the McArthur Group. In HALLENSTEIN, C.P. (Editor), 1994 - AusIMM Annual Conference: `Australian Mining looks north - the challenges and choices'. Australasian Institute of Mining and Metallurgy, Melbourne, 135-138. **HAINES, P.W., RAWLINGS, D.J., SWEET, I.P., PIETSCH, B.A., PLUMB, K.A., MADIGAN, T.L., & KRASSAY, A.A., - Blue Mud Bay, 1:250 000 geological series. Northern Territory Geological Survey, Explanatory Notes, SD53 7. **PAGE, R.W., & SWEET, I.P., (in press) - Geochronology of basin phases in the western Mount Isa Inlier, and correlation with McArthur Basin. Australian Journal of Earth Sciences. **PIETSCH, B.A., PLUMB, K.A., PAGE, R.W., HAINES, P.W., RAWLINGS, D.J., & SWEET, I.P., 1994 - A revised stratigraphic framework for the McArthur Basin, N.T. In HALLENSTEIN, C.P. (Editor), 1994 - AusIMM Annual Conference: `Australian Mining looks north - the challenges and choices'. Australasian Institute of Mining and Metallurgy, Melbourne, 135-138. **PLUMB, K.A., & ROBERTS, H.G., 1992 - The geology of Arnhem Land, Northern Territory. Bureau of Mineral Resources, Australia, Record, 1992/55, 193pp.|16-MAY-23
77145|Galiwinku Dolerite|Name source|After the township of Galiwinku located in the Arnhem Shelf (see http://www.ga.gov.au/place-names/PlaceDetails.jsp?fctext=POPL&submit1=G527&fctext=LOCB&fctext=BLDG&fctext=BLDG&fctext=LOCB, Record ID NT G527) GDA94 Zone 53L 561500mE  8670281mN  (12° 1' 41" S, 135° 33' 54"E)|16-MAY-23
77145|Galiwinku Dolerite|Unit history|First informally named by Goldberg 2010 and chemically defined by Hollis and Glass 2012|16-MAY-23
77145|Galiwinku Dolerite|Geomorphic expression|Subsurface radial dyke swarm.|16-MAY-23
77145|Galiwinku Dolerite|Type section locality|Howship 1:100 000 geological mapsheet, Cameco Australia Pty Ltd drill hole PLD0001 (available for viewing at the Northern Territory Geological Survey, Core Library, Darwin). Grid Reference: GDA94 Zone 53L 335346m E 8591678m N (12.7351°S, 133.483°E) Hollis and Glass 2010).|16-MAY-23
77145|Galiwinku Dolerite|Description at type locality|Intrusive into Mamadawerre Sandstone of the Kombolgie Subgroup, McArthur Basin in southeast Howship 1:100 00 geological mapsheet.|16-MAY-23
77145|Galiwinku Dolerite|Extent|Dykes intrude McArthur Basin (onshore) and extend radially to the north offshore into the sedimentary rocks beneath the Arafura Sea.|16-MAY-23
77145|Galiwinku Dolerite|General description|Subsurface extent of northeast and northwest-trending radial dykes which intrude the Paleo-Mesoproterozoic recognised from magnetic response. Extensive under cover in Milingimbi, Arnhem Bay Gove, Wessel Islands Truant Island and Junction Bay 1:250 000 geological maphseets.|16-MAY-23
77145|Galiwinku Dolerite|Thickness range|Unknown.|16-MAY-23
77145|Galiwinku Dolerite|Lithology|Quartz normative and olivine normative dolerite.|16-MAY-23
77145|Galiwinku Dolerite|Depositional environment|Genesis: Intrusive dyke swarm, possibly related to rifting (Goldberg 2010).|16-MAY-23
77145|Galiwinku Dolerite|Relationships and boundaries|Intrusive into the Paleo- to Mesoproteroic McArthur Basin. Chilled margin contact to Kombolgie Subgroup onshore in southeast Howship 1:100 000 geological mapsheet.|16-MAY-23
77145|Galiwinku Dolerite|Identifying features|Distinctive alkaline "hawaiite" geochemistry, strong magnetic response for dyke swarm under cover.|16-MAY-23
77145|Galiwinku Dolerite|Structure and Metamorphism|Not metamorphosed.|16-MAY-23
77145|Galiwinku Dolerite|Age reasons|The Galiwinku Dolerite has a SIMS U-Pb baddeleyite age of 207Pb/206Pb age of 1329 +/- 55 Ma (95% confidence, n = 8, MSWD = 1.3; Whelan et al in press).|16-MAY-23
77145|Galiwinku Dolerite|Correlations|Geohemically correlated Maningkorrirr and Mudginberri phonolites in Milingimbi and Alligator River 1:250 000, respectively. The latter has a Rb-Sr age of 1316 +/- 40 Ma (Page et al 1980). The Galiwinku Dolerite has similar geochemical signature to outcropping dolerite in Wellington Range 1:100 000 map geological, Cobourg Peninsula 1:250 000 geological mapsheet (Hollis and Glass, 2012) and dolerite intruding the Arnhem Province in Gove 1:250 000, but further investigation is required to confirm these relationships. Furthermore, alkali gabbro intruding the Tomkinson Province is geochemically similar to the Galiwinku Dolerite and yielded a SHRIMP U-Pb baddeleyite age of 1295 +/- 14 Ma (Melville 2010).|16-MAY-23
77145|Galiwinku Dolerite|Alteration and Mineralisation|Some chloritisation of feldspars, unmineralised.|16-MAY-23
77145|Galiwinku Dolerite|Geophysical Expression|Strong magnetic response.|16-MAY-23
77145|Galiwinku Dolerite|Geochemistry|Chemical similarities to Oceanic Island Basalt (OIB) with potassic hawaiite geochemical signature, characterised by elevated High Field Strength Element (HFSE) abundances (Hollis and Glass 2012).|16-MAY-23
77145|Galiwinku Dolerite|Defn author|LM Glass and JA Hollis 11-FEB-2016|16-MAY-23
77145|Galiwinku Dolerite|References|Goldberg AS, 2010. Dyke swarms as indictors of major extensional events in the 1.9-1.2 Ga Columbia supercontinent. Journal of Geodynamics, 50, 176-190. **Hollis JA and Glass LM, 2012. Howship-Oenpelli, Northern Territory. 1:100 000 geological map series explanatory notes, 5572, 5573. Northern Territory Geological Survey, Darwin.  **Melville PM, 2010. Geophysics and drilling collaboration final report for drilling program, Lake Woods Project, EL23687, EL24520, EL25631, EL27317, EL27318. Northern Territory Geological Survey, Open File Report, CR2010-0226. **Page RW, Compston W and Needham RS, 1980. Geochronology and evolution of the late-Archaean basement and Proterozoic rocks in the Alligator Rivers uranium field, Northern Territory, Australia: in Ferguson J and Goleby AB (editors) Uranium in the Pine Creek Geosyncline: proceedings of the International Uranium Symposium on the Pine Creek Geosyncline. International Atomic Energy Agency, Vienna, 39¿68. **Whelan JA, Glass LM, Hollis JA, Bleeker W, Chamberlin K and Soderlund U and Ernst RE, in press. Summary of results. TIMS and SIMS U-Pb baddeleyite dating of the Oenpelli and Galiwinku dolerites. Northern Territory Geological Survey, Record|16-MAY-23
37734|Gator Sandstone|Name source|Gator Waterhole, around 18o29'S, 137o32'E, a permanent waterhole in George Creek, MOUNT DRUMMOND.|16-MAY-23
37734|Gator Sandstone|Unit history|Previously mapped within (ie not differentiated from) Carrara Range Formation in First Edition MOUNT DRUMMOND (Smith and Roberts 1963). Subsequently mapped by Sweet (1984) as upper sandstone part of Mitchiebo Volcanics in Carrara Range region; identified informally as LPcms on mapface.|16-MAY-23
37734|Gator Sandstone|Geomorphic expression|Strongly resistant and ridge forming with white phototones.|16-MAY-23
37734|Gator Sandstone|Type section locality|Narrow parallel strike ridges at 18o42'S, 137o43'E, along northern edge of Little Range Fault in headwaters of Boomerang Creek, MOUNT DRUMMOND. Section extends from 786200mE 7930950mN (base) to 786300mE 7931200mN (top).|16-MAY-23
37734|Gator Sandstone|Extent|Carrara Range in southeastern MOUNT DRUMMOND.|16-MAY-23
37734|Gator Sandstone|Thickness range|100-700 m, with gradual increase from east to west.|16-MAY-23
37734|Gator Sandstone|Lithology|Silicified, pink to purple, fine- to very coarse grained, quartzose to sublithic sandstone, with scattered quartz granules and pebbles up to 2 cm in diameter and minor local beds or laminae of mudstone intraclasts and brown oxidised ?basalt clasts 0.1-1 cm in diameter. Medium to very thickly bedded with planar bedding and low-angle planar and trough cross-beds 10-80 cm thick. Overall, succession tends to coarsen upwards. Locally, contains thin recessive volcanic interval with loose float of vesicular basalt and brown laminated lithic sandy mudstone (?volcaniclastic sandstone). In reference area, marginally different succession incorporates lower, white, resistant sandstone subunit and upper, dark, moderately recessive, ferruginous sandstone subunit. Lower sandstone subunit comprises thickly bedded, white to pink, fine- to medium grained quartzose sandstone with trough cross-beds. Upper subunit dominated by red-brown to pink, friable,fine-grained, ferruginous lithic sandstone, with thin to medium-bedding, trough cross-beds, symmetric ripples and mudclasts. Middle 20 m of succession distinctly muddier and more ferruginous than above and below, and contains chocolate brown sandstone interbedded with micaceous siltstone and mudstone. Mudstone intraclasts, desiccation cracks and cross-lamination with a 10 cm wavelength are prolific. Upper few dekametres of sandstone is pink and notably more silicified than below.|16-MAY-23
37734|Gator Sandstone|Depositional environment|Moderate- to high-energy braided fluvial and/or shallow marine.|16-MAY-23
37734|Gator Sandstone|Relationships and boundaries|Of Carrara Range Group. Conformable on Mitchiebo Volcanics; unconformably overlain by Top Rocky Rhyolite. Locally removed by erosion preceding Surprise Creek Formation.|16-MAY-23
37734|Gator Sandstone|Age reasons|Constrained by underlying Murphy Inlier basement (>1845 Ma; Page et al 2000) and overlying Top Rocky Rhyolite (SHRIMP U-Pb zircon date of 1725 +/- 3 Ma; Page et al 2000).|16-MAY-23
37734|Gator Sandstone|Correlations|Based on stratigraphic position and lithology, Gator Sandstone is correlated with Sly Creek Sandstone in southern McArthur Basin (Rawlings 1999), which also contains a local basalt interval (Haines et al 1993).|16-MAY-23
37734|Gator Sandstone|Defn author|Rawlings, D.J. [defn published 2008]|16-MAY-23
37734|Gator Sandstone|References|**HAINES P.W., Pietsch B.A., Rawlings D.J. and Madigan T.L., 1993. Mount Young, Northern Territory (Second Edition); 1:250 000 Geological Map Series, sheet SD53-15. Northern Territory Geological Survey, Explanatory Notes.  **PAGE R.W., Jackson M.J. and Krassay A.A., 2000. Constraining sequence stratigraphy in north Australian basins: SHRIMP U-Pb zircon geochronology between Mt Isa and McArthur River. Australian Journal of Earth Sciences, 47, 3; 431-459.  **RAWLINGS D.J., 1999. Stratigraphic resolution of a multi-phase intracratonic basin system: the McArthur Basin, northern Australia. Australian Journal of Earth Sciences, 46, 5; 703-723.  **RAWLINGS D.J. Sweet I.P. and Kruse P.D., 2008. Mount Drummond, Northern Territory (Second Edition); 1:250 000 Geological Map Series, sheet SE53-12. Northern Territory Geological Survey, Map and Explanatory Notes.  **SMITH J.W. and Roberts H.G., 1963. Mount Drummond, N.T. (First Edition); 1:250,000 geological series, sheet SE53-12. Bureau of Mineral Resources, Geology and Geophysics, Map and Explanatory Notes.  **SWEET I.P., 1984. Carrara Range region, Northern Territory (First Edition); 1:100,000 geological series, portions of sheets 6460 and 6360. Bureau of Mineral Resources, Geology and Geophysics, Explanatory Notes.|16-MAY-23
37623|Geolsec Formation|Name source|After the Geolsec phosphate prospect, 3 km WNW of Batchelor, Northern Territory.|16-MAY-23
37623|Geolsec Formation|Unit history|Crick (1984) previously mapped Geolsec Formation as Buckshee Breccia overlain by Depot Creek Sandstone. Sandstone has been observed interlayered with breccia, therefore both rock types are now considered part of the same formation. In the Castlemaine Hill area around the Geolsec prospect, and north of Whites mine, much of the Depot Creek Sandstone on Crick's (1984) map is breccia including massive sandstone layers. The name Buckshee Breccia is now abandoned in favour of Geolsec Formation.|16-MAY-23
37623|Geolsec Formation|Type section locality|Geolsec phosphate prospect, 717180 mE 8558000 mN (lat. 131degrees 0' E, long. 13degrees 2' S).|16-MAY-23
37623|Geolsec Formation|Extent|The Geolsec Formation occurs around the margins of the Waterhouse Dome and in the vicinity of Dysons, Whites and Browns deposits on the southern margin of the Rum Jungle Dome in BYNOE, BATCHELOR and REYNOLDS RIVER 1:100 000 sheets.|16-MAY-23
37623|Geolsec Formation|Thickness range|Unknown.|16-MAY-23
37623|Geolsec Formation|Lithology|Haematite quartzite breccia interbedded with massive haematitic sandstone, siltstone and mudstone. Mudstone and siltstone may be phosphatic. Proportion of massive sandstone increases up-section. Quartzite breccia fragments are either silicified dolostone or milky vein quartz, depending on proximity to underlying Coomalie Dolostone.|16-MAY-23
37623|Geolsec Formation|Relationships and boundaries|Unconformably overlies Coomalie Dolostone and Whites Formation. Lower boundary recognised as sudden change from steeply dipping Coomalie Dolostone or Whites Formation to gently to moderately dipping sandstone and haematitic quartzite breccia. No units were observed directly overlying the Geolsec Formation.|16-MAY-23
37623|Geolsec Formation|Identifying features|Breccia units comprise characteristic white, angular, small to large pebble-sized quartzite fragments within a red, fine-grained, haematitic silica matrix. Siltstone units at Geolsec and other phosphate prospects are phosphatic.|16-MAY-23
37623|Geolsec Formation|Age reasons|Younger than 1780 Ma, last regional metamorphism and folding of Pine Creek Orogen rocks (Needham et al 1988).|16-MAY-23
37623|Geolsec Formation|Correlations|Unknown.|16-MAY-23
24284|Georgina Gap granitic gneiss|Name source|Georgina Gap, GR 5751-410160, Laughlen 1:100 000 Sheet area.|16-MAY-23
24284|Georgina Gap granitic gneiss|Unit history|Previously mapped by Wells & others (1968) as undivided Arunta Complex.|16-MAY-23
24284|Georgina Gap granitic gneiss|Type section locality|Reference area: Markedly dissected region immediately south of Georgina Gap at GR 5751-408155 in the Laughlen 1:100 000 Sheet area.|16-MAY-23
24284|Georgina Gap granitic gneiss|Extent|The unit crops out over an area of about 10 km2 along and east of the track to Whistleduck Bore immediately south of Georgina Gap. An apophysis of the body is photointerpreted to extend for 6 km westwards from the southern tip of the main body along the edge of the Wigley Block.|16-MAY-23
24284|Georgina Gap granitic gneiss|Lithology|The granitic gneiss has a biotite content of up to 20 percent and is coarse-grained for the most part. It contains conspicuous megacrysts of K-feldspar. The gneissic layering is not markedly developed.|16-MAY-23
24284|Georgina Gap granitic gneiss|Relationships and boundaries|The granitic gneiss appears to intrude the Mulga Creek granitic gneiss, unassigned gneiss and amphibolite (pC), and the Laughlen metamorphics. It appears to be localised at the northeastern extension of the Redbank Deformed Zone (Marjoribanks & Black, 1974).|16-MAY-23
24284|Georgina Gap granitic gneiss|Age reasons|Middle Proterozoic or older. Its megacrystic nature and weak gneissic fabric suggest a lithological correlation with the Gum Tree Granite which is dated at about 1000 m.y. (Allen & Black, 1979).|16-MAY-23
24284|Georgina Gap granitic gneiss|Proposed publication|Stewart & others, in prep.|16-MAY-23
24284|Georgina Gap granitic gneiss|Defn Reference|80/20787|16-MAY-23
24284|Georgina Gap granitic gneiss|Proposer|Shaw R.D. (in Shaw & others, in preparation)|16-MAY-23
81845|Ghost Gum Granite|Name source|Ghost Gum Bore (135.8337degreesE 22.9031degreesS (GDA 2020)) in Jinka 1:100 000 mapsheet, Northern Territory.|16-MAY-23
81845|Ghost Gum Granite|Geomorphic expression|The unit is generally poorly exposed, occurring as small pavements, blocky hills, and low-lying outcrop.|16-MAY-23
81845|Ghost Gum Granite|Type section locality|135.871degreesE 22.8978degreesS (GDA2020); access via private tracks.|16-MAY-23
81845|Ghost Gum Granite|Description at type locality|Medium-grained, equigranular K-feldspar?plagioclase?quartz leucogranite with accessory biotite, and rare relict biotite schlieren gneissosity interpreted to represent palaeosomes originating from the Eurobra Gneiss.|16-MAY-23
81845|Ghost Gum Granite|Extent|Isolated outcrops in southern HUCKITTA 1:250 000 mapsheet (Weisheit et al in prep), south of Anderson Creek and Elua Range, north of Arunta Creek and Harts Range. Possibly more widely distributed in the subsurface and extending into ILLOGWA CREEK. So far, it has only been recognised north of the Harts Range and Entia Dome.|16-MAY-23
81845|Ghost Gum Granite|General description|Ghost Gum Granite, and occurs as metre- to hundred-metre-scale bodies within the Eurobra Gneiss, from which it is interpreted to be derived.|16-MAY-23
81845|Ghost Gum Granite|Thickness range|Unknown.|16-MAY-23
81845|Ghost Gum Granite|Lithology|Medium-grained, equigranular K-feldspar-plagioclase-quartz leucogranite with accessory biotite, and rare relict biotite schlieren gneissosity interpreted to represent palaeosomes originating from the Eurobra Gneiss.|16-MAY-23
81845|Ghost Gum Granite|Depositional environment|Genesis: Possibly formed at the latest stages of extension or the beginning of compression in the Irindina Province. Unit was formed by partial melting of the Eurobra Gneiss during the Palaeozoic.|16-MAY-23
81845|Ghost Gum Granite|Relationships and boundaries|Derived by partial melting of the Eurobra Gneiss. Interpreted as younger than Riddock Metagabbro based on field relationship with the Eurobra Gneiss. Intruded by undivided pegmatite of the Irindina Province.|16-MAY-23
81845|Ghost Gum Granite|Identifying features|The only anatectic granite associated with the Eurobra Gneiss in the Irindina Province.|16-MAY-23
81845|Ghost Gum Granite|Structure and Metamorphism|Contains rare relict biotite schlieren gneissosity. Occurs in diatexite migmatite structure with parent Eurobra Gneiss. Locally weakly to moderately foliated.|16-MAY-23
81845|Ghost Gum Granite|Age reasons|A SHRIMP 206Pb/238U age of 467 +/- 9 Ma (Kositcin and Reno 2020) from a diatexite migmatite of the Eurobra Gneiss records the timing of metamorphism and associated partial melting, and may record the timing of Ghost Gum Granite melt formation.|16-MAY-23
81845|Ghost Gum Granite|Alteration and Mineralisation|Moderately weathered at surface; no known mineralisation.|16-MAY-23
81845|Ghost Gum Granite|Geophysical Expression|Irregular magnetic high zones and layers; together with Eurobra Gneiss in an area of gravity high response; no characteristic radiometric response.|16-MAY-23
81845|Ghost Gum Granite|Geochemistry|One sample of monzogranite is strongly peraluminous at the boundary of shoshonite-high-K series.|16-MAY-23
81845|Ghost Gum Granite|Defn author|Barry Reno, Anett Weisheit, Eloise Beyer, Pablo Farias (NT Department of Industry, Tourism and Trade, Northern Territory Geological Survey) 3-MAY-2022.|16-MAY-23
81845|Ghost Gum Granite|References|Kositcin N and Reno BL, 2020. Summary of results. Joint NTGS-GA geochronology project: Aileron and Irindina provinces, Jinka and Dneiper 1:100 000 mapsheets, 2019. Northern Territory Geological Survey, Record 2020-001.  **Reno BL, Weisheit A, Beyer EE and PG Farias, 2022. Jinka, Northern Territory. 1:100 000 geological map series explanatory notes, 6052. Northern Territory Geological Survey, Darwin.  **Weisheit A et al, in prep. Huckitta, Northern Territory (Third Edition). 1:250 000 geological map series explanatory notes, SF53-11. Northern Territory Geological Survey, Darwin.|16-MAY-23
27414|Giddy Granite|Name source|From Giddy RIver, wich flows northwards into southern part of Melville Bay.|16-MAY-23
27414|Giddy Granite|Type section locality|Aound the upper reaches of Giddy River.|16-MAY-23
27414|Giddy Granite|Extent|Poorly exposed in scattered smal inliers, beneath Early Cretaceous rocks and Cainozoic soiland lateriente, over about 340 km2 inland from  south-west of Melville Bay, in Gove 1:250 000 sheet area. Exposures can be divided into two areas, one large reasonably continuous exposure about 16 km west=north-west of mouth of Giddy River, and a group of simller exposures around headwaters of the Giddy River. These two areas have different rock types.|16-MAY-23
27414|Giddy Granite|General description|The Giddy Granite is best described in two areas. In the area around the Giddy River the Granite is distinguished by the abundance of large porphyroblasts (up to 20 cms across) of alkali feldspar and the presence in the groundmass, of either hornblende-biotite or fayalite-pyroxene-hornblende-biotite. The rocks are calc-alkaline granites or adamellites. Local belts of cataclasis are prominent. North of the Cato Laterite Deposit the granite is a massive, even-grained leucocratic micrographic granite with occasional chloritised biotite. The rocks are noted for their lack of large alkali feldspar porphyroblasts and paucity of ferromagnesian minerals. One sample from each area has been chemically analysed (Table 4) and Rhodes (1966) has identified the alkali feldspars as monoclinic forms (Table 3) typical of sub-volcanic granites. The rocks from both areas are chemically very similar, except for higher FeO/MgO ratio and more lime in the Giddy sample, and are similar to the Caledon Granite.|16-MAY-23
27414|Giddy Granite|Lithology|Massive pink coarse-grained frequently porphyroblastic granite. Micrographic and granophyric intergrowths common. Grainsize appears to decrease towards margins of body.|16-MAY-23
27414|Giddy Granite|Relationships and boundaries|Only relationship directly observed is that Giddy Granite is unconformably overlain by Lower Cretaceous sediments and Tertiary laterites. Massive post-tectonic-type granite. Correlated with Caledon Granite on basis of petrology and isotopic age. The western group of Giddy Granite outcrops resemble in rock type, and appear to grade into,overlying Spencer Creek Volcanics and unconformably overlain by Mount Bonner Sandstone. Assigned to the widespread associated post-tectonic granites and acid volcanics, about 1800 Ma old, in northern Australia.|16-MAY-23
27414|Giddy Granite|Age reasons|Orosirian (Late Palaeoproterozoic). Replicate analyses of biotite from a single sample of Giddy Granite (D53/4/6 gave a K-Ar minimum age of 1760 Ma (McDougall et al., 1965); this is similar to the 1750 Ma age obtained for the Caledon Granite. A single biotite from the same Giddy sample was sufficiently enriched in Rb87 to define a Rb-Sr age of 1786 +/- 50 Ma; a single total-rock sample gives agreement with the biotite with an assumed initial Sr87/Sr86 ratio of 0.720, but replicate analyses of K-feldspar give an age of 1705 Ma for the same initial ratio, indicating slight discordance due to some geological effect.|16-MAY-23
27414|Giddy Granite|Defn author|Plumb and Roberts (1992).|16-MAY-23
32943|Gillen Formation|Name source|The Gillen Formation was named after Mount Gillen (GDA94 53K 379028mN, 7377436mN) in ALICE SPRINGS|16-MAY-23
32943|Gillen Formation|Unit history|The Gillen Member was proposed by Wells et al (1967) and has since been in use.|16-MAY-23
32943|Gillen Formation|Constituents|5 informal units, where identifiable.|16-MAY-23
32943|Gillen Formation|Geomorphic expression|Dolostone of the Gillen Formation can form prominent strike ridges that extend for 10s of kilometres; smaller rounded ridges are also common.|16-MAY-23
32943|Gillen Formation|Type section locality|Between GDA94 53K 514733mE 7350485mN (base) and 53K 512735mE 7349832mN (top) begins at the base of the  Heavitree Quartzite cliffs and continues southwest towards Ringwood-Numery Road, approximately 1.5 km northeast of Waldo Pedlar Bore, ILLOGWA CREEK|16-MAY-23
32943|Gillen Formation|Extent|The Gillen Formation is exposed throughout the MacDonnell Ranges (HERMANNSBERG, ALICE SPRINGS, ILLOGWA CREEK) to the south of the ridge of Heavitree Quartzite, outcrop on RODINGA and HALE RIVER is minimal. Gillen Formation forms small hills and ridges of dolostone which are often spinifex covered.|16-MAY-23
32943|Gillen Formation|General description|The Gillen Formation is generally characterised by disharmonic folding resulting from salt withdrawal. The type section described here is unusual in that there is no evidence for intense folding and therefore it represented the best exposed, undeformed section.|16-MAY-23
32943|Gillen Formation|Thickness range|In type section: Overall thickness: 1505 m, Informal member 1: ~ 689 m thick, Informal member 2: ~ 136 m thick, Informal member 3: ~ 263 m, Informal member 4: ~ 85 m thick, Informal member 5: ~ 235m thick.  There is approximately 790 m of Bitter Springs Group in the Ellery Creek section, where (Wells et al 1967) included stromatolitic dolostone and red argillaceous limestone of the Loves Creek and Johnnys Creek formations, which left approximately 390 m of Gillen Formation. Due to folding that has occurred in the Gillen Formation, it is difficult to ascertain thickness in some areas, however, the where the true thickness has been calculated and measured it appears that the thickness of the formation is quite variable.|16-MAY-23
32943|Gillen Formation|Lithology|The Gillen Formation comprises five informal members although the unit as a whole is predominantly dolostone and stromatolitic dolostone, cherty limestone (and dolostone?) generally with minor grey shale and cross-bedded sandstone. Sandstone locally thickens to mappable subunits in the northeast. The base of the unit is marked by black shale. Additional rock types are gypsiferous siltstone, micaceous green shale; cross-bedded sandstone, and granule conglomerate. Informal member 1: stromatolitic dolostone with occasional sandstone beds and recessive, calcrete intervals that are likely to be calcareous siltstone. Dolostone beds become more dominant towards top of informal member and stromatolites become more frequent. Informal member 2 comprises variably fine- to coarse-grained or granular, quartz sandstone, felspathic quartz sandstone and subarkose/arkose. Sandstones are typically planar bedded, and bed thickness varies from thin- (<0.1m) to thick (<<0.6m) -bedded , but is predominantly thin- (<0.1m) to medium-bedded (<0.3m). Beds are typically grain-size laminated. The thinner beds are generally more felspathic than the thicker ones. Sorting and rounding of grains is generally moderate to good.Informal member 3 is predominantly stromatolitic dolostone. The base of the member comprises scattered outcrop of planar laminated, thinly to medium-bedded siliciclastic-bearing carbonate rocks. Overlying these sandstones are silicified, apparently recrystallised coarse-grained dolostone. Informal member 4 is a sandstone unit that coarse-grained, well-rounded felspathic quartz-sandstone, in which feldspar now forms a clay matrix at least in surface outcrop. Sandstone is thinly bedded and laminated on the scale of 2-3 mm. Planar bedding is dominant, although there are also low angle trough crossbeds, and tabular crossbeds in medium bed sets. Thin interbeds of coarse-grained to granular quartz sandstone, and sandstone at the base of the interval are typically more felspathic ie subarkosic, with sinuous crested symmetric and truncated ripple marks.  Overlying the exposed sandstone is an interval of approximately 40 m of poorly exposed fine-grained, well-sorted and well-rounded felspathic quartz sandstone. Informal member 5 comprises thin- to medium-bedded carbonate rocks (Figure 16) that are probably interbedded limestone (pale grey, greenish grey and yellow weathering surface) and dolostone (brown weathering surface). The limestones are characterised by laterally persistent, very-thin to thin parallel laminations. Differential hardness between laminae may result from variable fine-grained siliciclastic content. This unit continues upwards with thin to medium, planar bedded laterally persistent silicified micritic dolostone.|16-MAY-23
32943|Gillen Formation|Depositional environment|The Gillen Formation is likely to have been deposited in a quiet, shallow water marine setting that enabled the formation of stromatolites or algal mats. Periods of terrestrial sediment influx resulted in variably thick sandstone beds. Deposition of more siliciclastic units may be the result of periods of increased erosion or high rainfall/flooding events.|16-MAY-23
32943|Gillen Formation|Fossils|Acritarch assemblage (planktonic phytomicrofossils) containing about 35 forms (Zang and Walter 1992). Columnar Tungussia erecta stromatolites (Walter 1972) are generally restricted to informal member 3, however, occasional stromatolites were observed in informal member 5.|16-MAY-23
32943|Gillen Formation|Relationships and boundaries|Within the type section, the contact between the Gillen Formation and the underlying Heavitree Quartzite is unconformable. The upper contact with the Loves Creek Formation appears to be conformable. In other areas, where tectonism has occurred, the overlying contact is unconformable or disconformable with the Areyonga Formation and Pioneer Sandstone.|16-MAY-23
32943|Gillen Formation|Identifying features|Typically, the Gillen Formation is characterised by disharmonic folding associated with salt withdrawal. The carbonate rocks of the formation are generally monotonous and textural evidence for primary sedimentary characteristics is poorly preserved. This is likely due to early diagenetic dolomitisation and silicification.|16-MAY-23
32943|Gillen Formation|Structure and Metamorphism|The Gillen Formation is significantly folded and faulted throughout the Amadeus Basin. Disharmonic folding and salt withdrawal makes it difficult to determine the true extent of faulting and some repetition may have occurred.|16-MAY-23
32943|Gillen Formation|Age reasons|The age of the Gillen Formation is currently constrained to ca 820 Ma on the basis of geochemical correlation of the basalts in the Johnnys Creek Formation with the Amata Dolerite of the Musgrave Province (Edgoose 2013). However as the Johnnys Creek Formation is stratigraphically higher than the Gillen Formation it is likely that the Gillen Formation is older than 820 Ma. New detrital zircon U-Pb dating carried out as part of this study yielded a maximum depositional age of 896 +/- 24 Ma for  detrital zircon U-Pb SHRIMP sampled from informal member 3  (Kositcin et al 2014). This is considerably older than the inferred deposition of 820 Ma of the Bitter Springs Group.|16-MAY-23
32943|Gillen Formation|Correlations|None known, the Bitter Springs Group is interpreted to be a correlative of the Pinyinna Beds in the west of the Amadeus Basin.|16-MAY-23
32943|Gillen Formation|Alteration and Mineralisation|Gypsum along with halite was been identified throughout the Amadeus Basin in the Gillen Formation. Evaporites mostly occur in the core of diapiric structures in silicified dolostone hosts (NTGS 2004).  Copper: Copper mineralisation has been intersected in drilling of the Undoolya Gap Cu Prospect (ALICE SPRINGS) (Youles 1966), as well as at the Haags Prospect (HENBURY) (Edgoose 2013). Petroleum: Marshall et al (2007) described the Gillen Formation as part of the first of five petroleum systems in the Amadeus Basin. The Gillen Member is recognised as a potential source rock and has fair to good potential to generate intraformational hydrocarbons, particularly in the southern parts of the basin (Munson 2014).|16-MAY-23
32943|Gillen Formation|Geophysical Expression|The Gillen Formation is clearly seen in seismic imaging due to the salt that is contained within the unit.|16-MAY-23
32943|Gillen Formation|Defn author|VJ Normington, N Donnellan 2-Sep-2015. Approved: Jo Whelan and Verity Normington 28-Sep-2015.|16-MAY-23
32943|Gillen Formation|References|Edgoose C, 2013. Amadeus Basin: in Ahmad M and Munson TJ (editors) 'Geology and mineral resources of the Northern Territory; Special Publication 5', Northern Territory Government. **Kositcin N, Normington V and Edgoose C, 2014. Summary of results. Joint NTGS-GA geochronology project: Amadeus Basin, July 2013¿June 2014. NTGS Record 2015-001, Northern Territory Geological Survey. **Marshall TR, Dyson IA and Liu Keyu, 2007. Petroleum systems in the Amadeus Basin, central Australia: Were they oil prone?: in Munson TJ and Ambrose GJ (editors) 'Proceedings of the Central Australian Basins Symposium, Alice Springs, 16 - 18th August, 2005'. Alice Springs, Northern Territory Geological Survey, Special Publication 2, 136-146. **Munson TJ, 2014. Petroleum geology and potential of the onshore Northern Territory, 2014, Northern Territory Geological Survey, Report 22. **Normington VJ and Donnellan N, in prep. Characterisation of the Neoproterozoic stratigraphy of the northeast Amadeus Basin, Northern Territory. : in Northern Territory Geological Survey R (editor). **NTGS, 2004. Mineral commodities of the Northern Territory: compliation of secen 1989 reports prepard by Eupene Exploration Enterpries Pty Ltd, Northern Territory Geological Survey Record 2004-009. **Oehler DZ, Oehler JH and Stewart AJ, 1979. Algal fossils from a late Precambrian, hypersaline lagoon. Science 205, 388-390. **Walter MR, 1972. Stromatolites and the biostratigraphy of the Australian Precambrian and Cambrian. Special Publication Palaeontology 11. **Wells AT, Ranford LC, Stewart AJ, Cook PJ and Shaw R, 1967. Geology of the north-eastern part of the Amadeus Basin, Northern Territory BMR Report 113, Australia. **Youles LP, 1966. Diamond Drill Report Undoolya Gap Copper Prospect NTGS Tecnical Report 1966-001: in Survey NTG (editor), Northern Territory Government  **Zang W and Walter MR, 1992. Late Proterozoic and Cambrian microfossils and biostratigraphy, Amadeus Basin, central Australia. Association of Australasian Palaeontologists Memoir 12.|16-MAY-23
7242|Gilruth Volcanic Member|Name source|Mount Gilruth 133o04'30"E 13o02'45" Mt Evelyn 1:250 000 Sheet area.|16-MAY-23
7242|Gilruth Volcanic Member|Type section locality|Small peak on Arnhem Land Plateau at 133o18'15"E, 12o52'30"S. Alligator River 1:250 000 Sheet area. Peak is medium to coarse quartz sandstone of the Kombolgie Formation with a prominent bench 10 m from top of peak developed at the base of the Gilruth Volcanic Member. Rubble on this bench contains weathered tuffaceous siltstone, rare amygdaloidal and vesicular purple and black basalt, and banded quartz jasper rock amongst laterite scree.|16-MAY-23
7242|Gilruth Volcanic Member|Extent|A meandering outcrop pattern with a surface width of generally 50 m extending from the headwaters of the Katherine River to the headwaters of the Goomader River; with an overall NE trend. Approx. 5 km2 surface exposure. Subsurface extent >5000 km2.|16-MAY-23
7242|Gilruth Volcanic Member|Thickness range|<5 m.|16-MAY-23
7242|Gilruth Volcanic Member|Lithology|Tuffaceous siltstone, amygdaloidal and vesicular basalt, banded jasper quartz rock. Unit ubiquitously covered in sandstone rubble from overlying unit. Litholotgies only apparent as rubble amongst nodular laterite scree on a prominent bench commonly marking the base of the member.|16-MAY-23
7242|Gilruth Volcanic Member|Relationships and boundaries|Interbedded in sandstone of the Carpentarian Kombolgie Formation, about 100 m above the Nungbalgarri Volcanic Member. Boundaries of Member not yet found exposed. Base appears to be predominantly tuffaceous siltstone, underlain by sandy siltstone which is the topmost part of the underlying sandstone member of the Kombolgie Formation.|16-MAY-23
7242|Gilruth Volcanic Member|Age reasons|1720-1200 m.y. (Page & Needham in prep.) interbedded in Carpentarian Kombolgie Formation.|16-MAY-23
7242|Gilruth Volcanic Member|Proposed publication|Journal of the Geological Society of Australia|16-MAY-23
7242|Gilruth Volcanic Member|Unit name|Gilruth Volcanic Member (of the Kombolgie Formation)|16-MAY-23
21856|Glen Helen Metamorphics|Name source|Glen Helen Pastoral Lease.|16-MAY-23
21856|Glen Helen Metamorphics|Unit history|Previously mapped as metamorphic lithological types (Glikson & Green, 1983). Included in the Dashwood migmatites (informal) of Glikson (1984).|16-MAY-23
21856|Glen Helen Metamorphics|Geomorphic expression|Low rubble-covered hills.|16-MAY-23
21856|Glen Helen Metamorphics|Type section locality|About 3km south to southwest of Glen Helen homestead, along the gas pipe line, and especially in Dashwood Creek near GR306200 7418100, Glen Helen 1:100 000 Sheet area.|16-MAY-23
21856|Glen Helen Metamorphics|Extent|West of Ormiston Pound, continuing west into the Mount Liebig Sheet area.|16-MAY-23
21856|Glen Helen Metamorphics|Lithology|Compositionally layered, banded quartzofeldspathic gneiss, granitic gneiss, biotite gneiss, amphibolite, calc-silicate rock, metasediments. Migmatites abundant in rocks of suitable composition.|16-MAY-23
21856|Glen Helen Metamorphics|Relationships and boundaries|Intruded by Teapot Granite Complex and by Stuart dykes.|16-MAY-23
21856|Glen Helen Metamorphics|Structure and Metamorphism|Complexly folded, deformed and metamorphosed during the Argilke Tectonic Event at about 1650-1680 Ma.|16-MAY-23
21856|Glen Helen Metamorphics|Age reasons|Middle Proterozoic: 1660 Ma (ion-microprobe age of zircon, also rare cores at 1730 Ma; Black and Shaw, 1992b). May include older rocks south of Madderns Yard.|16-MAY-23
21856|Glen Helen Metamorphics|Defn author|R.G. Warren & R.D. Shaw, 1 July 1991.|16-MAY-23
21856|Glen Helen Metamorphics|Comments|This 'definition' is missing the details of references mentioned in the synonymy and age, and shows no signs on the card of having been approved.|16-MAY-23
79224|Gloaming Formation|Name source|Mount Gloaming (133.5127deg E  -24.6143deg S) in central-eastern HENBURY.|16-MAY-23
79224|Gloaming Formation|Unit history|Formerly mapped as part of Winnall beds of Ranford et al (1965) now redefined as Winnall Group.|16-MAY-23
79224|Gloaming Formation|Type section locality|Type locality: GDA94 53J 308614mE 7276909mN (133.10952deg E, -24.61009deg S) ~5 km southwest of Henbury Meteorite Craters; and reference locality GDA94 53J 277095mE 7261395mN (132.79591deg E, -24.74587deg S) at the western end of the Seymour Range.|16-MAY-23
79224|Gloaming Formation|Description at type locality|Alternately, thinly- and medium- bedded, internally planar-parallel laminated, flaggy to fissile sandstone indicating cyclicity on the scale of a few metres. Beds are arranged in thick, planar cross-stratified sets that show good lateral persistence. The sandstone comprises fine- to medium-grained, generally well-sorted and well-rounded quartz arenite and subarkose. The unit is characterised by a high population density of small-scale sedimentary structures including a range of ripple marks, desiccation features, weathered-out shale clasts, and current/streaming lineation.|16-MAY-23
79224|Gloaming Formation|Extent|Throughout central-eastern HENBURY 1:250 000 and may extend to the east and southeast (into RODINGA and possibly FINKE), but unlikely to extend west into LAKE AMADEUS and BLOODS RANGE.|16-MAY-23
79224|Gloaming Formation|Thickness range|~ 170m minimum.|16-MAY-23
79224|Gloaming Formation|Lithology|Fine- to medium-grained, generally well-sorted and well-rounded quartz arenite and subarkose.|16-MAY-23
79224|Gloaming Formation|Depositional environment|Shallow marine to intertidal.|16-MAY-23
79224|Gloaming Formation|Fossils|Probable Bunyerichnus dalgarnoi.|16-MAY-23
79224|Gloaming Formation|Diastems or hiatuses|Not recognised, but indications for shallow-marine to intertidal sedimentation suggests breaks in deposition are common. Weathered-out shale clasts are the only evidence for possible intraformational erosion.|16-MAY-23
79224|Gloaming Formation|Relationships and boundaries|In part a lateral facies equivalent of the Breaden and Froud formations with which it has transitional contacts.|16-MAY-23
79224|Gloaming Formation|Identifying features|Thinly-bedded and flaggy to fissile, with a wide range of sedimentary structures, eg ripple marks, desiccation and syneresis cracks, rivularites (`elephant skin¿ texture), current lineation, weathered-out shale clasts. Dark red-brown colour when fresh.|16-MAY-23
79224|Gloaming Formation|Structure and Metamorphism|Folded and faulted, but apparently unmetamorphosed.|16-MAY-23
79224|Gloaming Formation|Age reasons|Correlation with the Waldo Pedlar Member of Pertatataka Formation suggests a post ca 578 Ma Ediacaran age based on Ediacaran Leiosphere Palynoflora assemblage zones described by Grey (2005) from the Pertatataka Formation.|16-MAY-23
79224|Gloaming Formation|Correlations|Probably correlates with Waldo Pedlar Member of Pertatataka Formation. Is in part laterally equivalent to the Breaden and Froud formations of Winnall Group.|16-MAY-23
79224|Gloaming Formation|Geophysical Expression|Generally linear, low total magnetic intensity typical of Winnall Group.|16-MAY-23
79224|Gloaming Formation|Defn author|N Donnellan, VJ Normington, 27-FEB-2017.|16-MAY-23
79224|Gloaming Formation|References|Grey K, 2005. Ediacaran palynology of Australia. Australian Association of Australasian Palaeontologists, Memoir 31, 1-439.***Ranford LC, Cook PJ and Wells AT, 1965. The geology of the central part of the Amadeus Basin, Northern Territory. Bureau of Mineral Resources, Australia, Report 86.|16-MAY-23
24291|Gnallan-a-gea Arkose|Name source|Gnallan-a-gea Bore, Hay River 1:250 000 Sheet area.|16-MAY-23
24291|Gnallan-a-gea Arkose|Unit history|"Quartz greywacke" of the Field River Beds of Smith (1963).|16-MAY-23
24291|Gnallan-a-gea Arkose|Type section locality|GEO707, Field River Syncline, Adam Special 1:100 000 Geological Sheet area (GR 53KQQ783281).|16-MAY-23
24291|Gnallan-a-gea Arkose|Extent|Hay River and Tobermory 1:250 000 Sheet areas.|16-MAY-23
24291|Gnallan-a-gea Arkose|Thickness range|This ranges from a minimum of 1450 m in the Bat Hills (where the top and bottom of the section are not exposed) to 10 m in the Keepera Ridges, with a minimum of 345 m in the type section (where the top of the section is not exposed).|16-MAY-23
24291|Gnallan-a-gea Arkose|Lithology|Light brown to grey fine to very coarse grained pebbly arkose, sandstone, siltstone and shale. The arkose and sandstone is frequently cross-stratified.|16-MAY-23
24291|Gnallan-a-gea Arkose|Relationships and boundaries|The lower boundary is placed at the base of the lowest pebbly arkose or sandstone above the Wonnadinna Dolomite. Regional correlations suggest that this boundary is a disconformity because a slight angular unconformity occurs at this position in the Mopunga Trough, and because of the abrupt change of lithology. The upper boundary is rarely exposed, but at Mt Winnecke and Mt Barrington (both in the Hay River 1:250 000 sheet area) it appears to be gradational with the Grant Bluff Formation, and in the Keepera Ridges the Elyuah Formation conformably overlies the Gnallan-a-gea Arkose. The upper boundary is placed at the top of the uppermost pebbly arkose.|16-MAY-23
24291|Gnallan-a-gea Arkose|Age reasons|Adelaidean. Correlated with the lower Pertatataka Formation of the Amadeus Basin.|16-MAY-23
21894|Gove Sandstone|Name source|Gove Peninsula (AMG PG950500) in the northeastern corner of Arnhem Land, Gove 1:250 000 scale mapsheet area.|16-MAY-23
21894|Gove Sandstone|Unit history|Previously undifferentiated "Spencer Creek Volcanics" of Dunnet (1965).|16-MAY-23
21894|Gove Sandstone|Geomorphic expression|Comprises white upstanding strike ridges of sandstone with a strong macroscopic conjugate joint set. Outcrop is slabby to bouldery with a pseudokarstic weathering pattern.|16-MAY-23
21894|Gove Sandstone|Type section locality|At latitude 12o11'40"S, longitude 136o31'20"E (AMG PG655515, Gove map sheet area), 10 km southeast of Mount Bonner. The base of the section is at PG662510 and the top boundary stratotype is at PG650517. Due to poor exposure, a lower boundary stratotype is not defined.|16-MAY-23
21894|Gove Sandstone|Extent|Outcrop occurs as a series of disconnected northeast-oriented strike ridges of white sandstone, stretching between the Cato River floodplain (PG550410, northeastern Arnhem Bay 1:250 000 scale map sheet area) and near Mount Bonner (PG670550, northwestern Gove 1:250 000 scale map sheet area).|16-MAY-23
21894|Gove Sandstone|Thickness range|310 m near type section. To the north and south, the sequence has been partly or completely removed by the unconformity at the base of the overlying Mount Bonner Sandstone.|16-MAY-23
21894|Gove Sandstone|Lithology|White to pink, fine- to very coarse-grained (mostly medium-grained) mature quartzose sandstone. Generally medium- to thick-bedded with low- to moderate-angle trough (and rarely planar) cross-beds or flat-bedding. Locally thin-bedded and rippled (mainly symmetrical) and less commonly, very thick-bedded and channelled with large-scale trough cross-beds. Rounded to angular quartz pebbles (up to 5 cm diameter) common at bottom and mid-way through the formation. In some areas, the basal 5 m of the unit is feldspathic or lithic, containing numerous quartz pebbles and pink felsic volcanic rock fragments. Mudstone intervals and intraclasts are rare and are restricted to the upper part (~ top 50 m) of the sequence. Outcrop exhibits characteristic surface silicification.|16-MAY-23
21894|Gove Sandstone|Depositional environment|Shallow water, low- to moderate-energy, possibly represented by fan-delta, with braided fluvial influences near the base.|16-MAY-23
21894|Gove Sandstone|Relationships and boundaries|Lower sandstone formation of the Spencer Creek Group. It lies disconformably upon the felsic igneous rocks of the Yanungbi Volcanics and is conformably overlain by the fine-grained siliciclastic rocks of the Yuduyudu Formation. The lower contact is not exposed but appears to be mildly erosional. The basal part of the Gove Sandstone is notably lithic and felspathic. Around PG570420, this erosion has completely removed the volcanics and the Gove Sandstone sits unconformably on the Dhalinybuy Granite. The contact with the overlying Yuduyudu Formation is poorly exposed at the top boundary stratotype, but appears to be a conformable gradation from white quartzose sandstone into ferruginous fine-grained sandstone and mudstone. North and south of the type section this formation has been partly or completely eroded prior to deposition of the unconformably overlying Mount Bonner Sandstone.|16-MAY-23
21894|Gove Sandstone|Age reasons|Palaeoproterozoic (Statherian). Constrained by the enclosing Yanungbi Volcanics/Latram Granite and Cato Volcanics, which are ~1710 Ma (Rawlings and others, in prep.).|16-MAY-23
21894|Gove Sandstone|Correlations|Rawlings and others (in prep.) and Rawlings (1994) suggest correlation with the upper parts of the Tawallah and Katherine River Groups in the southern and western McArthur Basin respectively. Locally, it correlates with the Fagan Volcanics in southern Arnhem Bay and northern Blue Mud Bay map sheet areas.|16-MAY-23
21894|Gove Sandstone|Proposed publication|Arnham Bay-Gove 1:250 000 Geological Map Series, Northern Territory, National Geoscience Mapping Accord, Explanatory Notes (Rawlings and others, in prep.).|16-MAY-23
21894|Gove Sandstone|Category|2|16-MAY-23
21894|Gove Sandstone|Defn approved by|Brakel A.T., Haines P.W.|16-MAY-23
21894|Gove Sandstone|Proposer|Rawlings D.J.|16-MAY-23
21894|Gove Sandstone|Reserved? Yes/No|Yes|16-MAY-23
7652|Grace Creek Granite|Name source|Named by Randal (1963) the Grace Creek Granite has been described by Stewart (1965) and Walpole & others (1968). Recent work has changed the extent, stratigraphic relationship and age of the unit (Needham & Stuart-Smith, in press).|16-MAY-23
7652|Grace Creek Granite|Type section locality|Hills 3 km north of Grace Creek tin prospect, latitude 14o6'S, longitude 132o52'E; red xenolithic xenocrystic fine to medium granite.|16-MAY-23
7652|Grace Creek Granite|Extent|Southeastern half of the triangular "Grace Creek Inlier" which is coextensive with the Katherine River basin upstream from Katherine Gorge. About 750 km2 of outcrop, mainly south of Ironbark Creek, with possibly about another 100 km2 concealed by Kombolgie Formation mainly east of the 'Grace Creek Inlier".|16-MAY-23
7652|Grace Creek Granite|Lithology|Reddish xenolithic and xenocrystic granite, roughly zoned into porphyritic microgranite near the margin, through porphyritic pink-grey and slightly porphyritic grey-green medium grained granite, to fine to medium grained equigranular light grey-pink biotite granite near the centre, around the Grace Creek tin prospect (Needham & Stuart-Smith, 1984). The microgranite is very similar to the reddish xenolithic ignimbrites of the Plum Tree Creek Volcanics which surround most of the Grace Creek Granite, but can be distinguished from them by the presence of corroded orthoclase xenocrysts up to 6 cm across. Both the granite/microgranite and the ignimbrite contain xenocrysts or phenocrysts of quartz, in places up to 1 cm across.|16-MAY-23
7652|Grace Creek Granite|Relationships and boundaries|Owing to the similarity between the microgranite and surrounding ignimbrite an accurate boundary cannot be established. They may indeed by coeval and comagmatic. The granite intrudes the Hindrance Creek Sandstone of the Edith River Group, and is unconformably overlain by Kombolgie Formation sandstone. It is cut by numerous NE-trending dolerite dykes which also cut the Kombolgie Formation.|16-MAY-23
7652|Grace Creek Granite|Age reasons|Leggo (in Walpole and others 1968) reported a Rb/Sr isochron age of 1470 Ma which is demonstrably incorrect in view of the granite's unconformity beneath ~1645 Ma Kombolgie Formation (Page & others, 1980). Field evidence suggests that the granite is coeval with the Plum Tree Creek Volcanics which have an age of 1803 +/- 10 Ma (Page R.W., pers. comm. 1984). Relationships with the Eva Valley Granite and Tollis Formation in the Yeuralba area are equivocal and provide no constraints on the age of the granite.|16-MAY-23
7652|Grace Creek Granite|Proposed publication|Needham & Stuart-Smith (in press) Australian Journal of Earth Sciences. Needham & Stuart-Smith (in press) BMR Journal|16-MAY-23
7652|Grace Creek Granite|Status|1|16-MAY-23
7690|Grant Bluff Formation|Name source|Grant Bluff located at lat.22deg 42' S, long 135deg 45' E, near the NW end of the Elyuah Range.|16-MAY-23
7690|Grant Bluff Formation|Type section locality|Smith (1964), BMR Report 67, shows the location of the type section of the Grant Bluff Formation in fig.11, p29 (as X3), but  the figure is hard to correlate with the prelim. Huckitta 1:250k map included as Plate 8. The site is described (p27) as 'located about 10 miles south-east of Grant Bluff' at 'Lat. 22deg 45'30" S, Long.135deg 53' E.|16-MAY-23
7690|Grant Bluff Formation|Identifying features|The definition of the grant Bluff Formation of Smith (1964) is here restricted to exclude the upper, recessively weathering sequence in the type section and elsewhere; i.e. to exclude the sequence from the 168 m level up to the base of the Mt Baldwin Formation in section 13 of Walter (1979) (which is the type section, designated X3 by Smith, 1964). The Grant Bluff Formation as redefined consists largely of thin-bedded sandstone in the Alcoota and Huckitta 1:250 000 Sheet area; in the northeastern Hay River Sheet area it is much thicker and includes thick interbeds of siltstone.  As redefined, the formation is 90 m thick in its type section. The base is as defined by Smith, at the base of the lowest thin-bedded sandstone above the shales of the Elyuah Formation. The top is defined here as the top of the uppermost thin-bedded sandstone below the recessively weathering shales, siltstones, dolomite and sandstone of the Elkera Formation.|16-MAY-23
7690|Grant Bluff Formation|References|Walter, M.R. 1980. BMR Report 214|16-MAY-23
21914|Grindall Formation|Name source|Grindall Point (PF130280) and nearby Mount Grindall and Grindall Bay in the Blue Mud Bay 1:250 000 scale map sheet area.|16-MAY-23
21914|Grindall Formation|Unit history|'Grindall Metamorphics' (Plumb and Roberts, 1965; 1992). Note that outcrops near Grindall Point mapped as 'Grindall Metamorphics' by Plumb and Roberts (1965) are now assigned to the Bradshaw Complex.|16-MAY-23
21914|Grindall Formation|Geomorphic expression|Low rubbly hills, wave cut platforms and cliffs along coasts.|16-MAY-23
21914|Grindall Formation|Type section locality|Plumb and Roberts (1992) nominate the eastern end of Morgan Island (latitude 13o28'S, longitude 136o06'E; AMG PF195103) as the type locality. Here the sequence is folded and mostly steeply dipping. A short distance to the west the formation is intruded by the Bukudal Granite and is overlain unconformably by flat-lying Woodah Sandstone (Groote Eylandt Group).|16-MAY-23
21914|Grindall Formation|Extent|Eastern Blue Mud Bay 1:250 000 scale map sheet area, specifically eastern flank of Coast Range, Morgan Island, Burney Island, northern Bickerton Island and small islands to the north of Bickerton Island.|16-MAY-23
21914|Grindall Formation|Thickness range|Unknown as the sequence is tightly folded and no stratigraphic base or top can be identified. Probably in excess of 1000 m thick.|16-MAY-23
21914|Grindall Formation|Lithology|Red-brown to grey-green, fine- to medium-grained, thin- to thick-bedded, lithic sandstone generally interbedded with mudstone. Discrete sandstone beds are typically sharp-based and often graded. Schist, phyllite and metasandstone locally present in the Coast Range area.|16-MAY-23
21914|Grindall Formation|Depositional environment|Considered to be, at least in part, a turbiditic sequence.|16-MAY-23
21914|Grindall Formation|Relationships and boundaries|Oldest known component of the Arnhem Inlier. No base exposed. Contact with younger units clearly marked by distinct angular unconformity commonly succeeded by a basal conglomerate. Overlain unconformably by various units of the Groote Eylandt Group and locally by the Jalma Formation and un-named volcanics along Coast Range. Intruded by the Bradshaw Complex, Bukudal Granite, and various mafic and felsic dykes.|16-MAY-23
21914|Grindall Formation|Age reasons|Probably Palaeoproterozoic, but constrained only by the minimum age of 1870 Ma provided by the oldest known intrusives, the Bradshaw Complex (Pietsch and others, 1994). Pietsch and others (1994) indicate it was deposited pre-Barramundi Oreogeny (1885-1870 Ma).|16-MAY-23
21914|Grindall Formation|Correlations|May correlate with other pre-McArthur Basin sedimentary and metasedimentary sequences in the Pine Creek Inlier, Mirarrmina Complex and the Murphy Inlier.|16-MAY-23
21914|Grindall Formation|Defn author|Haines P.W.|16-MAY-23
21914|Grindall Formation|Proposed publication|Groote Eylandt Region 1:250 000 Geological Map Series, Explanatory Notes (Pietsch and others, in prep.).|16-MAY-23
21914|Grindall Formation|Comments|The change of name from 'Grindall Metamorphics' is considered necessary to reflect the predominant lithology of the unit. Although locally metamorphosed, most outcrops do not warrant being termed metamorphic.|16-MAY-23
21914|Grindall Formation|Category|1|16-MAY-23
21914|Grindall Formation|Defn approved by|Braken A.T., Haines P.W.|16-MAY-23
21914|Grindall Formation|Name first published by|Plumb & Roberts 1965 as Grindall Metamorphics|16-MAY-23
21914|Grindall Formation|Proposer|Rawlings D.J., Haines P.W., Pietsch B.A. (after Plumb and Roberts, 1965; 1992)|16-MAY-23
21914|Grindall Formation|Reserved? Yes/No|Yes|16-MAY-23
33979|Groote Eylandt Group|Name source|Groote Eylandt, Northern Territory (lat. 14o 00'S, long. 136o 30'E).|16-MAY-23
33979|Groote Eylandt Group|Unit history|Largely comprised of the former 'Groote Enylandt beds' (Plumb and Roberts, 1965, 1992) with the addition of the old 'Bickerton Volcanics', most outcrops of which are now termed Bickerton Rhyollite.|16-MAY-23
33979|Groote Eylandt Group|Constituents|Subdivided into two subgroups and nine formations. Listed below in stratigraphic order up the page [from top to bottom]. Alyangul Subgroup: Dalumbu Sandstone, Bartalumba Basalt, Alyinga Sandstone = Woodah Sandstone (possible lateral equivalents).  Bustard Subgroup: Milyakburra Formation = Milyema Formation (possible lateral equivalents), Bickerton Rhyolite, Abarungkwa Sandstone, Erringkarri Rhyolite.|16-MAY-23
33979|Groote Eylandt Group|Type section locality|As for each component formation.|16-MAY-23
33979|Groote Eylandt Group|Extent|Groote Eylandt, Bickerton Island and adjacent smaller islands in Blue Mud Bay and minor occurences on nearby mainland coastal area in BLUE MUD BAY, PORT LANGDON, CAPE BEATRICE and ROPER RIVER.|16-MAY-23
33979|Groote Eylandt Group|Thickness range|The composite of all the maximum thicknesses is about 1650m.|16-MAY-23
33979|Groote Eylandt Group|Lithology|Volumetrically dominated by siliciclastic sedimentary rocks ranging from sandstone to boulder conglomerate. Interbedded with localised porphyritic rhyolite in the Bustard Subgroup and more consistent basaltic rocks in the Alyangula Subgroup.|16-MAY-23
33979|Groote Eylandt Group|Depositional environment|Predominantly fluviatile sedimentary components with subaerial volcanics. Some shallow marine intervals.|16-MAY-23
33979|Groote Eylandt Group|Relationships and boundaries|The group unconformably overlies the Grindall Formation and ~1840Ma granite. The top of the unit is eroded and unconformably overlain by Cretaceous and Cainozoic rocks and sediments. Intruded by mafic dykes.|16-MAY-23
33979|Groote Eylandt Group|Age reasons|Palaeoproterozoic|16-MAY-23
33979|Groote Eylandt Group|Correlations|Bustard Subgroup: Edith River Group which underlies the McArthur Basin in the Katherine region. Alyangula Subgroup: lower part of Tawallah and Katherine River Groups of McArthur Basin.|16-MAY-23
7866|Gum Ridge Formation|Name source|Gum Ridge, 27km eastnortheast of Tennant Creek township, TENNANT CREEK.|16-MAY-23
7866|Gum Ridge Formation|Geomorphic expression|Low, rubble-covered plateaux and rises.|16-MAY-23
7866|Gum Ridge Formation|Type section locality|84.4-234.9m depth in cored drillhole NTGS96/1 (GRMV214640 HELEN SPRINGS; lat. 18o24'55"S, long. 134o14'40"E). Core stored at NTGS Core Library, Darwin.|16-MAY-23
7866|Gum Ridge Formation|Extent|Presumed to underlie all or most of Barkly Sub-basin in western Georgina Basin; outcrop extensive in HELEN SPRINGS, TENNANT CREEK, BONNEY WELL and FREW RIVER.|16-MAY-23
7866|Gum Ridge Formation|Thickness range|150.5m in type section.|16-MAY-23
7866|Gum Ridge Formation|Lithology|Subsurface- grey, often partially dolomitised massive, ribbon, bioclast, lithoclast and minor onkoid limestone, minor cryptomicrobial dololaminite and grey siliciclastic mudstone; brown-maroon siltstone at base. At surface these are pervasively chertified and lateritised.|16-MAY-23
7866|Gum Ridge Formation|Relationships and boundaries|Rests disconformably on Helen Springs Volcanics. Disconformably overlain by strata assigned to Anthony Lagoon beds; boundary placed at sharp change from uppermost thick carbonate interval (thickness about 60m) upward into thin yellow-brown dolomitic-siliciclastic mudstone.|16-MAY-23
7866|Gum Ridge Formation|Structure and Metamorphism|Flat-lying to very gently dipping.|16-MAY-23
7866|Gum Ridge Formation|Age reasons|Ordian-early Templetonian (early Middle Cambrian) based on co-occurrence of trilobites Redlichia and Xystridura (Opik in Ivanac 1954:30-32,1970, 1975).|16-MAY-23
7866|Gum Ridge Formation|Correlations|Montejinni Limestone (Traves 1955) of Wiso Basin, Tindall Limestone (Randal 1962; Malone 1962) of Daly Basin, Linnekar Limestone (Traves 1955) and Panton Formation (Dow & Gemuts 1967) of Ord Basin, Top Springs Limestone (Plumb & Rhodes 1963, 1964) of northern Georgina Basin, based on closesimilarity of invertebrate fossil faunas (Kruse 1990, 1991, 1997).|16-MAY-23
7866|Gum Ridge Formation|References|DOW, D.B. & GEMUTS, I., 1967- 1:250000 geological series explanatory notes. Dixon Range, W.A. Bureau of Mineral Resources, Australia. **IVANAC, J.F., 1954- The geology and mineral deposits of the Tennant Creek gold-field, Northern Territory. Bureau of Mineral Resources, Australia, Bulletin 22, 164p., 44pls. **KRUSE, P.D., 1990- Cambrian palaeontology of the Daly Basin. Northern Territory Geological Survey, Report 7. **KRUSE, P.D., 1991- Cambrian fauna of the Top Springs Limestone, Georgina Basin. The Beagle, Records of the Northern Territory Museum of Arts and Sciences 8,  169-188. **KRUSE, P.D., 1997- Cambrian palaeontology of the eastern Wiso and western  Georgina Basins. Northern Territory Geological Survey, Report 9. **MALONE, E.J., 1962- 1:250 000 geological series explanatory notes. Pine Creek, N.T. Bureau of Mineral Resources, Australia. **OPIK, A.A., 1970- Redlichia of the Ordian (Cambrian) of northern Australia and  New South Wales. Bureau of Mineral Resources, Australia, Bulletin 114. **OPIK, A.A., 1975- Templetonian and Ordian Xystridurid trilobites of Australia.  Bureau of Mineral Resources, Australia, Bulletin 121. **PLUMB, K.A. & RHODES, J.M., 1963- Explanatory notes on the Wallhallow 1:250 000 geological sheet series SE53-7, Northern Territory. Bureau of Mineral Resources, Australia, Record 1963/116 (unpublished). **PLUMB, K.A. & RHODES, J.M., 1964- 1:250000 geological series explanatory notes.  Wallhallow, N.T. Bureau of Mineral Resources, Australia. **RANDAL, M.A., 1962- 1:250000 geological series explanatory notes. Fergusson River, N.T. Bureau of Mineral Resources, Australia. **TRAVES, D.M., 1955- The geology of the Ord-Victoria region, Northern Territory. Bureau of Mineral Resources, Australia, Bulletin 27.|16-MAY-23
84113|Gum Waterhole Member|Name source|Unit name derived from Gum Waterhole, situated on Crow Creek at approximately (GDA94) 18°25’49”S 136°50’30”E in the central MOUNT DRUMMOND 1:250 000 mapsheet area in the Northern Territory.|
84113|Gum Waterhole Member|Unit history|Outcrops of this unit were originally mapped as the “Mullera Formation” in the First Edition MOUNT DRUMMOND 1:250 000 mapsheet (Smith and Roberts, 1963a, b) and subsequently remapped as the “Tobacco Member” (in part) of the “Crow Formation” in the Second Edition MOUNT DRUMMOND 1:250 000 mapsheet (Rawlings et al, 2008). [That part of] the “Crow Formation” which contains the “Gum Waterhole Member” has itself been renamed to the “Racecourse Formation”.|
84113|Gum Waterhole Member|Geomorphic expression|Unit is moderately resistant in outcrop with well developed, banded white and dark brown phototones.|
84113|Gum Waterhole Member|Type section locality|There is no type locality nominated for this member. A reference area is nominated in the western MOUNT DRUMMOND 1:250 000 mapsheet, in the vicinity of (GDA94) 18°23’17”S 136°44’45”E (53K 684433mE 7965994mN).|
84113|Gum Waterhole Member|Extent|Unit outcrops in the north-western portion of the MOUNT DRUMMOND 1:250 000 mapsheet, Northern Territory, [NW of the Mitchiebo Fault].|
84113|Gum Waterhole Member|Thickness range|Unit thickness is variable, but about 300 m.|
84113|Gum Waterhole Member|Lithology|(i) medium to very thickly bedded, diffusely bedded, quartzose to lithic, locally ferruginous and micaceous (± glauconitic), fine- to medium-grained sandstone with amalgamated low-angle trough and hummocky cross-stratification; (ii) medium- to coarse-grained glauconitic sandstone, containing small red/brown mudstone flakes, pits after evaporites and trough cross-beds and; (iii) minor decimetre-scale beds of very coarse to granule-bearing, pebbly lithic sandstone, with parallel lamination. After Rawlings et al (2008).|
84113|Gum Waterhole Member|Depositional environment|Unit is interpreted as depositing in a shallow intertidal to shallow marine, storm-influenced shelf setting.|
84113|Gum Waterhole Member|Relationships and boundaries|The Gum Waterhole Member conformably overlies the undivided lower portion of the Racecourse Formation (formerly part of Crow Formation), and is unconformably overlain by the Playford Sandstone (South Nicholson Group).|
84113|Gum Waterhole Member|Identifying features|Highly feldspathic in outcrop in comparison to surrounding units.|
84113|Gum Waterhole Member|Age reasons|Maximum depositional age derived from U-Pb SHRIMP dating of detrital zircons: Top Lily Sandstone Member of the Playford Sandstone (stratigraphically overlies the Gum Waterhole Member): GA Sample 2785628 – 1546 ± 26 Ma (Kositcin and Carson, 2019). Gum Waterhole Member (formerly Tobacco Member): GA sample 3305197 – 1591 ± 7 Ma (Kositcin et al, 2020). Ten Mile Creek Member (formerly Top Lily Sandstone Member) of the Fish Hole Formation (formerly Playford Sandstone) (stratigraphically underlies the Gum Waterhole Member): GA Sample 2786167 – 1656 ± 12 Ma (Kositcin and Carson, 2019). Therefore, the potential depositional age range for the Gum Waterhole Member can be considered to extend from ca. 1591 ± 7 Ma to 1546 ± 26 Ma.|
84113|Gum Waterhole Member|Correlations|The Gum Waterhole Member of the Racecourse Formation, based on similar maximum depositional age estimates, can be correlated with Lawn Hill Formation, also within the McNamara Group (Kositcin and Carson, 2019). The Gum Waterhole Member may be correlative with components of the lower Favenc package (Rawlings, 1999) of the McArthur Basin.|
84113|Gum Waterhole Member|Geophysical Expression|Moderate radiometric response.|
84113|Gum Waterhole Member|Defn author|Elliot Foley, Jack Simmons, Ben Williams, Charles Verdel (Northern Territory Geological Survey), Chris Carson (Geoscience Australia) 31-MAY-2023.|
84113|Gum Waterhole Member|Comments|Note: All locations are based on the GDA94 geodetic datum. Standard series 1: 100 000 and 1: 250 000 mapsheet names are shown in uppercase.|
84113|Gum Waterhole Member|References|Carson, C. J., Kositcin, N., Anderson, J. R., and Henson, P. A. in prep. A revised Proterozoic tectono-stratigraphy of the South Nicholson region, Northern Territory, Australia - insights from SHRIMP U-Pb detrital zircon geochronology. Australian Journal of Earth Sciences. 
 **Kositcin N and Carson CJ, 2019. New SHRIMP U-Pb zircon ages from the South Nicholson and Carrara Range regions, Northern Territory. Geoscience Australia, Record 2019/09.  **Kositcin N, Carson CJ, Anderson JR, Doublier MP and Murr J, 2020. Exploring for the Future - New SHRIMP geochronology constraints on the basin evolution of the South Nicholson region. Geoscience Australia, Record 2020/025.  **Rawlings DJ, 1999. Stratigraphic resolution of a multiphase intracratonic basin system: the McArthur Basin, northern Australia. Australian Journal of Earth Sciences 46(5), 703-723.  **Rawlings DJ, Sweet IP and Kruse PD, 2008. Mount Drummond, NT (Second Edition). 1:250 000 Geological Map Series Explanatory Notes, Sheet SE 53-12. Northern Territory Geological Survey, Darwin, Northern Territory.  **Simmons JM, Williams B, Carson, C and Verdel C, 2023a. Mount Drummond, Northern Territory 1:250 000 Geological Map, Sheet SE 53-12 (Third Edition). Northern Territory Geological Survey, Darwin, Northern Territory.  **Simmons JM, Williams B, Carson, C and Verdel C, 2023b. Mount Drummond, Northern Territory 1:250 000 Geological Map Explanatory Notes, Sheet SE 53-12 (Third Edition). Northern Territory Geological Survey, Darwin, Northern Territory.  **Smith JW and Roberts HG, 1963a. Mount Drummond, NT (First Edition). 1:250 000 Geological Map Series Explanatory Notes, Sheet 53-12. Bureau of Mineral Resources, Canberra.  **Smith JW and Roberts HG, 1963b. Mount Drummond, NT (First Edition). 1:250 000 Geological Map Series, Sheet SE 53-12. Bureau of Mineral Resources, Canberra.|
27994|Gundi Sandstone|Name source|From Gundi Creek in KATHERINE, which intersects the formation at around lat. 14o24'S, long. 133o00'E.|16-MAY-23
27994|Gundi Sandstone|Unit history|Replaces the name "Gundi Greywacke"; see below under COMMENTS for discussion.|16-MAY-23
27994|Gundi Sandstone|Geomorphic expression|Resistant ridges and plateaux, deeply incised along joints, to give a highly distinctive rough surface.|16-MAY-23
27994|Gundi Sandstone|Type section locality|From lat. 14o13.5'S, long. 133o7.5'E (base) to 14o13.6'S, long. 133o8.1'E (top).|16-MAY-23
27994|Gundi Sandstone|Extent|The most southwesterly outcrops are in the Waterhouse Syncline in northeastern KATHERINE; more extensive outcrops are in MOUNT MARUMBA and southeastern MILINGIMBI 1:250 000 sheet areas.|16-MAY-23
27994|Gundi Sandstone|Thickness range|130 m in type section, but ranging from 80 m to 300 m within a few kilometres of that section on northwestern limb of Waterhouse Syncline.|16-MAY-23
27994|Gundi Sandstone|Lithology|Lithologically rather uniform, of medium- to very coarse-grained and minor pebbly sandstone. Monocrystalline and polycrystalline quartz comprises 70-80%, lithic fragments 5-15% and feldspar less than 5% (generally less than 3%) of grains. Sericite/illite is common, mainly as a constituent of lithic fragments, but to a lesser extent as an interstitial mineral. The interstitial mineral is clearly diagenetic, and rarely exceeds 1% by volume of the rock. Furthermore, it appears to have formed during late diagenesis as it postdates the quartz cement in many cases.|16-MAY-23
27994|Gundi Sandstone|Depositional environment|Mainly braided fluvial; may be minor shallow marine.|16-MAY-23
27994|Gundi Sandstone|Relationships and boundaries|The contact with the underlying Diamond Creek Volcanics is placed at the abrupt change from vesicular basic volcanic rocks to quartz arenite. The contact is sharp and presumed unconformable. The upper contact is placed at the upper limit of quartz arenite, with a change to the more lithic sandstone,  cobble to boulder conglomerate, and mafic volcanics of the overlying West Branch Volcanics. The contact is locally unconformable where conglomerate lies above sandstone, but may be conformable elsewhere.|16-MAY-23
27994|Gundi Sandstone|Age reasons|Statherian Period of Palaeoproterozoic. The age is constrained only by the 1830 Ma age for parts of the underlying Edith River Group, and by the 1710 Ma age for the overlying West Branch Volcanics. The actual age is likely to be much closer to that of the West Branch Volcanics, as Diamond Creek volcanism, which preceeded Gundi deposition, appears to be an early phase of the activity which culminated in extrusion of the West Branch Volcanics.|16-MAY-23
27994|Gundi Sandstone|Correlations|Upper Tawallah Group in central McArthur Basin (in part); particularly Warramana Sandstone.|16-MAY-23
27994|Gundi Sandstone|Comments|The Gundi Sandstone was mapped and described by Ruker (1959) as the Gundi Creek Greywacke Member of the Kombolgie Formation. Randal (1963) modified the name to Gundi Greywacke Member and assigned it to his newly erected Diljin Hill Formation. Roberts & Plumb (1965) raised the unit to formation rank as the Gundi Greywacke, and this conception was maintained by Walpole and others (1968). The published name is varied here because the unit is not a greywacke, but a relatively well sorted quartz arenite or sublitharenite with minor authigenic clay "pseudomatrix".|16-MAY-23
27994|Gundi Sandstone|References|RANDAL, M.A., 1963 - KATHERINE, NT, 1:250 000 geological series. Bureau of Mineral Resources, Explanatory Notes, SD53-9. **RUKER, R., 1959 - The geology of the Diljin Hill, Black Cap, Waterhouse West and Canopy Rock West areas, Northern Territory. Bureau of Mineral Resources, Australia, Record 1959/67. **ROBERTS, H.G., & PLUMB, K.A., 1965 - MOUNT MARUMBA, NT, 1:250 000 geological series. Bureau of Mineral Resources, Explanatory Notes, SD53-6. **WALPOLE, B.P., CROHN, P.W., DUNN, P.R., & RANDAL, M.A., 1968 - Geology of the Katherine-Darwin Region, Northern Territory. Bureau of Mineral Resources, Australia, Bulletin 82, 304 pp.|16-MAY-23
27064|Gwynne Sandstone|Name source|Mount Gwynne (AMG GR LS845978) on the Barrow 1:1000 000 sheet (5654).|16-MAY-23
27064|Gwynne Sandstone|Unit history|Originally mapped as undifferentiated Arunta Block (Smith and Milligan, 1964).|16-MAY-23
27064|Gwynne Sandstone|Geomorphic expression|Strike ridges with pale air photo tones and well defined bedding trends.|16-MAY-23
27064|Gwynne Sandstone|Type section locality|On the northwestern part of Taylor 1:100 000 sheet; base at AMG GR LS966579 (latitude 21o10'40"S, 134o00'14"E) and top at GR LS967580 (latitude 21o10'36"S, longitude 134o00'17"E).|16-MAY-23
27064|Gwynne Sandstone|Extent|Northern part of the Crawford 1:100 000 shet (5655), western and southwestern part of the Taylor 1:100 0000 sheet (5755), and the northern part of the Home of Bullion 1:100 000 sheet (5754).|16-MAY-23
27064|Gwynne Sandstone|Thickness range|Up to about 500 m on the Crawford 1:100 000 sheet. In the Taylor 1:100 000 sheet area the maximum thickness is about 150 m at the type section and decreases to about 40 m further south at AMG GR MS074451.|16-MAY-23
27064|Gwynne Sandstone|Lithology|(in decreasing order of abundance): Feldspathic/lithic/micaceous arenite: medium- to very coarse-grained, medium- to thick-bedded, cross-bedded, poorly sorted. Minor quartz arenite, fine arenite and siltstone interbeds, commonly gritty or pebbly. Pebbles up to 40 mm, principally of subangular vein quartz and fine arenite.|16-MAY-23
27064|Gwynne Sandstone|Relationships and boundaries|Represents the basal formation of the Wauchope Subgroup of the Hatches Creek Group in this area. Conformable or disconformable on the Ooradidgee Subgroup. Conformably overlain by the Strzeleckie Volcanics. In the northwest Crawford Range the Gwynne Sandstone is overlain by the Illoquara Sandstone with probable disconformity.|16-MAY-23
27064|Gwynne Sandstone|Structure and Metamorphism|Tightly to isoclinally folded, faulted.|16-MAY-23
27064|Gwynne Sandstone|Age reasons|The maximum age of the Hatches Creek Group is considered to be Early Proterozoic (Blake and others, 1987).|16-MAY-23
27064|Gwynne Sandstone|Correlations|Possibly correlates with the Unimbra Sandstone (Blake and others, 1985).|16-MAY-23
27064|Gwynne Sandstone|Proposed publication|Barrow Creek 1:250 000 Geol. Series, Explan. Notes, NT. Geological Survey|16-MAY-23
27064|Gwynne Sandstone|Category|2|16-MAY-23
80726|Haddon Volcanics|Name source|After the topographic feature Haddon Head GDA94 zone 53, 604100mE, 851500mN (135.9621degrees E, -13.4317degrees S)|16-MAY-23
80726|Haddon Volcanics|Unit history|Previously mapped and described as undifferentiated volcanics unnamed rhyolite (Pietsch et al 1998, Haines et al 1999).|16-MAY-23
80726|Haddon Volcanics|Geomorphic expression|Pavements and low outcrops comprising boulders.|16-MAY-23
80726|Haddon Volcanics|Type section locality|Pavement and low boulder outcrop occurring at the base of the Coast Range approximately 11 km south of its northern most extent. GDA94 zone 53, 588978mE, 8510538mN (135.8221deg E, -13.4717deg S).|16-MAY-23
80726|Haddon Volcanics|Description at type locality|Low outcrops comprising pavements and boulders of rust coloured porphyritic rhyolite.|16-MAY-23
80726|Haddon Volcanics|Extent|1.5 km strike length along the base of the Coast Range, beginning approximately 11 km south of the northernmost extent of the range.|16-MAY-23
80726|Haddon Volcanics|General description|The type location forms part of a series of low bouldery outcrops that extend for 1.5 km strike along the plain immediately adjacent to the Coast Range. First outcrops occur approximately 11 km south of the northern-most extend of the Coast Range.|16-MAY-23
80726|Haddon Volcanics|Thickness range|Typically <50 m, but locally up to 100 m thick.|16-MAY-23
80726|Haddon Volcanics|Lithology|Rust coloured porphyritic rhyolite consisting of K-feldspar, plagioclase and quartz phenocrysts set in a fine-grained groundmass of K-feldspar-plagioclase-quartz and iron-oxide minerals. Zircon and titanite are accessory phases, both occur as inclusions in K-feldspar phenocrysts and in the groundmass.|16-MAY-23
80726|Haddon Volcanics|Depositional environment|Extrusive or high level intrusive.|16-MAY-23
80726|Haddon Volcanics|Relationships and boundaries|Unconformably overlain by the Jalma Formation and Coast Range Sandstone of the McArthur Basin. Intrudes and is unconformable on the Grindall Formation and unnamed metaigneous rocks of the Arnhem Province.|16-MAY-23
80726|Haddon Volcanics|Identifying features|Strongly porphyritic containing abundant large (up to 3 cm length) K-feldspar phenocrysts.|16-MAY-23
80726|Haddon Volcanics|Age reasons|LA-ICP-MS U-Pb zircon dating yields a magmatic crystallisation age of 1712 ± 2 Ma (Whelan et al 2018).|16-MAY-23
80726|Haddon Volcanics|Correlations|On the basis of lithological, stratigraphic, chronologic and geochemical similarities the Haddon Volcanics are tentatively correlated with porphyritic rhyolites of the Fagan Volcanics of the Donydji Group and felsic volcanics of the Spencer Creek Group, both of the McArthur Basin. The Donydji Group is exposed in the Mitchell Ranges Fault Zone and the northern part of the Walker Fault Zone north-northwest of the Coast Range in the ARNHEM BAY 1:250 000 mapsheet. Two samples of rhyolite from the Maidjunga and Dhupuwamirri members of the Fagan Volcanics have previously been dated, yielding SHRIMP U-Pb zircon ages of 1707 ? 12 Ma and 1706 ? 10 Ma, respectively (Page 1992). The Spencer Creek Group is exposed east of the Mirarrmina Inlier and unconformably overlies the Arnhem Province in GOVE 1:250 000 mapsheet. A sample of rhyolite of the Yanungbi Volcanics and the comagmatic subvolcanic Latram Granite (both assigned to the McArthur Basin) have previously been dated, yielding SHRIMP U-Pb zircon ages of 1712 ? 5 Ma (Kositcin et al 2015) and 1712 ? 10 Ma (Page 1996), respectively.|16-MAY-23
80726|Haddon Volcanics|Alteration and Mineralisation|Chlorite and sericite are common alteration phases replacing K-feldspar phenocrysts and groundmass minerals.|16-MAY-23
80726|Haddon Volcanics|Geophysical Expression|Unit is too small to reconcile in available geophysical imagery.|16-MAY-23
80726|Haddon Volcanics|Geochemistry|Rhyolite to alkali rhyolite, SiO2 from 68.24 to 75.01 wt%, peraluminous (aluminium saturation index from 1.04-3.38), alkali-calcic to alkali.|16-MAY-23
80726|Haddon Volcanics|Defn author|Jo Whelan, Northern Territory Geological Survey 04-AUG-2018.|16-MAY-23
80726|Haddon Volcanics|Proposed publication|Whelan JA, Munson TJ, Weisheit A, Woodhead JD, Thompson J and Meffre S, 2018. Summary of Results NTGS LA-ICP-MS U-Pb-Hf program: Arnhem Province and McArthur Basin, July 2015-June 2016. Northern Territory Geological Survey, Record 2019-007.|16-MAY-23
80726|Haddon Volcanics|References|Haines PW, Rawlings DJ, Sweet IP, Pietsch BA, Plumb KA, Madigan TL and Krassy AA, 1999. Blue Mud Bay SD53-7 1:250 000 geological map series explanatory notes, Northern Territory Geological Survey, Darwin. **Kositcin N, Whelan JA and Edgoose CJ, 2015. Summary of results. Joint NTGS-GA geochronology project: McArthur Basin, July 2014-June 2015. Northern Territory Geological Survey, Record 2015-008.  **Page R, 1996. GA sample ID 91772241 Geoscience Australia's Geochron Delivery system. <http://www.ga.gov.au/geochron-sapub-web/geochronology/shrimp/search.htm> [accessed Aug 2018].  **Pietsch BA et al 1998. Blue Mud Bay, Second Edition (1:250 000 scale geological map) Northern Territory Geological Survey Darwin.|16-MAY-23
26306|Hagen Member|Name source|After Hagen's bore at AMG reference NS 158055 on Elkedra.|16-MAY-23
26306|Hagen Member|Type section locality|Holostratotype: In cored diamond drillhole ELK7A between 153.48 and 248.76 m. The collar locality is latitude 21o39.5'S and longitude 135o9.5'E (AMG reference NS 162052) in Elkedra. The core is stored in the NT Geological Survey core store at Alice Springs.|16-MAY-23
26306|Hagen Member|Extent|Intersected in NTGS cored drillholes ELK6 and ELK7A. No known outcrop.|16-MAY-23
26306|Hagen Member|Thickness range|In ELK7A is 95.28 m thick, in ELK6 (AMG reference NR051740) is about 115 m thick.|16-MAY-23
26306|Hagen Member|Lithology|The holostratotype is summarised below. Above 153.48 m in ELK7A is the upper part of the Chabalowe Formation. The top of the Hagen Member of the Chabalowe Formation is identified by the thick gypsum and anhydrite-rich bed, underlying the sandstone-dominant upper unit of the Chabalowe Formation. TOP: 15.38 m (153.48-169.31 m) Interbedded gypsum, gypsiferous siltstone and chert (silicified algal laminate); minor anhydrite. 3.89 m (169.31-173.20 m) Dolostone, algal laminate and fine-grained dolarenite; minor dololutite. 9.38 m (173.20-182.58 m) Massive gypsum (satin spar) interbedded with siltstone, chert and dolostone, minor anhydrite. 55.47 m (182.58-238.05 m) Dolostone in part stromatolitic, dolorudite, dolarenite, dololutite, intraformational breccia. 10.71 m (238.05-248.76 m) Dolostone, silty grainstone, dolomitic siltstone.  BOTTOM: Below 248.76 m is dark-coloured, carbonaceous and fossiliferous, dolomitic siltstone of the Arthur Creek Formation.|16-MAY-23
26306|Hagen Member|Relationships and boundaries|Lenticular and represents the basal section of the Chabalowe Formation in Elkedra; laterally equivalent to and partly overlies the Arthur Creek Formation. Unconformably overlies Proterozoic rocks in ELK6. The Hagen Member is distinguished from the upper part of the Chabalowe Formation by the abundance of evaporite minerals and significantly less terrigenous clastic material.|16-MAY-23
26306|Hagen Member|Age reasons|Middle Cambrian as inferred from its relationship with the Arthur Creek Formation which contains trilobite fauna of Templetonian age.|16-MAY-23
26306|Hagen Member|Category|2|16-MAY-23
26306|Hagen Member|Proposer|Morris D.G.|16-MAY-23
26306|Hagen Member|Unit name|Hagen Member of the Chabalowe Formation (Symbol: Cmh)|16-MAY-23
25689|Hale Formation|Name source|Hale Plain, which extends east-west between The Garden and Claraville homesteads, Alice Springs 1:250 000 Sheet area.|16-MAY-23
25689|Hale Formation|Unit history|The sediments of the Hale Plain have been referred to as Arltungan Series by Madigan (1932), Arltungan Formation by Madigan (1936), Arltunga Series by Hossfeld (1954), and Arltungan Beds by Joklik (1955). (The Arltunga Quartzite of Chewings (1928) is now mapped as part of the Heavitree Quartzite). Smith (1963(b)) revised the name to Arltunga Beds. The type locality of the Beds is in a separate basin from the Hale Formtion, and is located at the western end of Paddys Plain,   km west of Arltunga, where they comprise arenaceous limestone, silicified limestone, and pebbly sandstone. Hence the Arltunga Beds differ lithologically, and were deposited in a separate place from the Hale Formation, and the name Arltunga Beds is restricted to the sediments in Paddys Plain.|16-MAY-23
25689|Hale Formation|Type section locality|Diamond Drillhole BMR 2 at GR 240088 Alice Springs 1:250 000 Sheet area.|16-MAY-23
25689|Hale Formation|Extent|The unit crops out sporadically across the Hale Plain, but is better known in subcrop from extensive drilling information (Clarke).|16-MAY-23
25689|Hale Formation|Thickness range|10-75 m (approximate).|16-MAY-23
25689|Hale Formation|Lithology|Kaolinitic quartzose sandstone, siltstone, and mudstone grading locally at the margins of the basin into coarse-grained, poorly sorted boulder conglomerate. A thin horizon of lignite in subcrop is named the Ulgnamba Lignite Member.|16-MAY-23
25689|Hale Formation|Relationships and boundaries|The Formation is underlain in places by a laterite profile with well-developed ferruginous mottled and leached zones. It is overlain at one locality nortwest of Claraville homestead by a unit of greenish-grey siltstone and chalcedonic limestone (informal unit Tw). Elsewhere, the formation is overlain by unconsolidated Cainozoic deposits - mainly alluvium.|16-MAY-23
25689|Hale Formation|Age reasons|The lignite member is possibly Eocene. The underlying weathering profile is possibly Maastrichtian to Early Eocene (Idnurm & Senior, 1978). Younger intercalated silcrete is possibly Late Oligocene to Miocene.|16-MAY-23
25689|Hale Formation|Proposed publication|Stewart & others, in prep.|16-MAY-23
25689|Hale Formation|References|01/31585; 01/31586;B026; 01/31593; RC79/047; 98/29305; |16-MAY-23
25689|Hale Formation|Defn Reference|80/20787|16-MAY-23
25689|Hale Formation|Proposer|Shaw R.D., Senior B.R. (in Shaw & others, in prep.)|16-MAY-23
24304|Hanlon Subgroup|Name source|Hanlon 1:100 0000 Sheet area (Sheet 6056), Frew River 1:250 000 Sheet area, Northern Territory.|16-MAY-23
24304|Hanlon Subgroup|Unit history|None. Corresponds to the Upper Hatches Creek Group of Blake & Wyche (1983 - BMR Rec. 1983/18) and Blake & others (1982 - BMR Rep. 239, 1983 - BMR 83), except that it also includes the Errolola Sandstone (at its base).|16-MAY-23
24304|Hanlon Subgroup|Constituents|From base to top - Errolola Sandstone, Alinjabon Sandstone, Lennee Creek Formation, Canulgerra Sandstone, Vaddingilla Formation, Yaddanilla Sandstone.|16-MAY-23
24304|Hanlon Subgroup|Type section locality|Reference area: Western part of Hanlon 1:100 000 Sheet area, west of Vaddingilla Rockhole (GR 681996).|16-MAY-23
24304|Hanlon Subgroup|Extent|Nearly complete section of Subgroup exposed in western part of Hanlon 1:100 000 Sheet area; lower part preserved in keels of several synclines in the Hatches, Elkedra, Davenport Range, Bonney, and Murray Downs 1:100 000 Sheet areas (Frew River, Elkedrak, Bonney Well, and Barrow Creek 1:250 000 Sheet areas).|16-MAY-23
24304|Hanlon Subgroup|Thickness range|Maximum expoised is about 5200 m, in western part of Hanlon 1:100 000 Sheet area.|16-MAY-23
24304|Hanlon Subgroup|Lithology|Fine to medium-grained quartzose and feldspathic/lithic/kaolinitic arenites, siltstone, and shale; minor coarse arenite, pebbly conglomerate, calcareous beds, and mafic lava; cross-bedding, wave and current ripple marks and mudflakes common.|16-MAY-23
24304|Hanlon Subgroup|Relationships and boundaries|Conformably overlies the Wauchope Subgroup of the Hatches Creek Group. Unconformably overlain by Cambrian rocks.|16-MAY-23
24304|Hanlon Subgroup|Age reasons|Younger than 1870 m.y. - U-Pb zircon age of volcanics in the Warramunga Group unconformably overlain by the Hatches Creek Group. Older than 1640 m.y. - Rb-Sr whole-rock approximate age of granite intruding the Hatches Creek Group.|16-MAY-23
24304|Hanlon Subgroup|Comments|Discussion: The Hanlon Subgroup is the youngest of three subgroups making up the Hatches Creek Group. The 6 formations comprising the Hanlon Subgroup are probably all marine - the sandstones appear to have been lain down in nearshore, partly intertidal environments and the finer grained rocks in deeper, quieter water. The subgroup differs from the two older subgroups of the Hatches Creek Group in that it contains few volcanics and virtually no fluvial sediments.|16-MAY-23
24304|Hanlon Subgroup|Defn Reference|86/25362|16-MAY-23
24304|Hanlon Subgroup|Proposer|Sweet I.|16-MAY-23
24306|Harry Anorthositic Gabbro|Name source|Harry Bore (GR 5651-958295), in Burt 1:100 000 Sheet area (also synonymous with Harry Creek 23o16'S, 133o50'E Alice Springs 1:250 000 Sheet area).|16-MAY-23
24306|Harry Anorthositic Gabbro|Unit history|Previously mapped by Wells & others (1968) as undivided Arunta Complex.|16-MAY-23
24306|Harry Anorthositic Gabbro|Type section locality|3 km west-southwest of Johannsen's Phlogopite Mine at GR 5751-055292.|16-MAY-23
24306|Harry Anorthositic Gabbro|Extent|The unit crops out in an east-west belt, and forms an area of subdued relief in the foothills of the Utnalanama Range southwest of Johannsen's Phlogopite Mine (GR 5751-079306), Laughlen 1:100 000 Sheet area.|16-MAY-23
24306|Harry Anorthositic Gabbro|Lithology|The most common rock type of the unit is anorthositic gabbro in the classification of Buddington (1939 p.19), although rock types range from pyroxenitic to anorthositic end members. Ultramafic and mafic end members are less common than anorthositic rocks. The rock has been regionally metamorphosed, and only a few relict igneous patches survive.|16-MAY-23
24306|Harry Anorthositic Gabbro|Relationships and boundaries|The Gabbro appears to be a single body which intrudes, and is thought to be highly interfolded with, the Utnalanama granulite. The gabbro is truncated in the northeast by an interpreted unconformity separating it from the overlying Erontonga metamorphics. It is also truncated in the southwest by the Gumtree Granite, and in the south by the Harry Creek Deformed Zone.|16-MAY-23
24306|Harry Anorthositic Gabbro|Age reasons|Mid-Proterozoic or older. The granulite facies metamorphism which affects the unit has been dated at 1800 m.y. using 40Ar-39Ar methods (Allen & Stubbs, in press).|16-MAY-23
24306|Harry Anorthositic Gabbro|Proposed publication|Stewart & others in prep.|16-MAY-23
24306|Harry Anorthositic Gabbro|Comments|Note on rock type name: The adoption of igneous, rather than metamorphic, terminology follows international usage (e.g. in Greenland) for similar rocks.  Remarks: A R. Allen considers that because the Gabbro unconformably underlies the Erontonga metamorphics, it should not be included in the Strangways Metamorphic Complex.|16-MAY-23
24306|Harry Anorthositic Gabbro|Defn Reference|80/20787|16-MAY-23
24306|Harry Anorthositic Gabbro|Proposer|Shaw R.D., Allen A.R. (in Shaw & others, in prep.)|16-MAY-23
24307|Harverson Granite|Name source|Harverson Pass (276500E, 7528900N), lowest point in Reynolds Range and 2.5 km E. of nearest exposure of Harverson Granite, Reynolds Range 1:100 000 Sheet area.|16-MAY-23
24307|Harverson Granite|Type section locality|A group of large tors at 280600E, 7532800N, 4.5 km SSW of Lander Rock in Reynolds Range 1:100 000 Sheet area.|16-MAY-23
24307|Harverson Granite|Extent|An equant body about 8 km across which crops out between Lander Rock and Harverson Pass, in Reynolds Range 1:100 000 Sheet area.|16-MAY-23
24307|Harverson Granite|Lithology|Coarse porphyritic leucocratic grey granite, massive (structureless), consisting of tubby phenocrysts of microcline up to 7 cm long in groundmass of microcline, plagioclase, quartz, biotite, and muscovite (the last two interleaved in places). Deuterically altered.|16-MAY-23
24307|Harverson Granite|Relationships and boundaries|Intrudes and metamorphoses Lander Rock beds; is ;intruded by a large number of quartz veins (48 mapped), by a few dykes of aplite and pegmatite. Not intruded by basic dykes. Contact with adjoining Mount Airy Orthogneiss (q.v.) obscured by alluvium, but Mount Airy Orthogneiss is intruded by numerous basic dykes and therefore is probably intruded by Harverson grnaite after emplacement of basic dykes finished. |16-MAY-23
24307|Harverson Granite|Identifying features|Reason for proposed name:  Distinctive granite mass and different in texture and dyke abundance from neighbouring granites.|16-MAY-23
24307|Harverson Granite|Age reasons|No isotopic date available (sampled 1972 L.P. Black). Adjoining (and older?) Mount jAiry Orthogneiss is possibly a facies variant of or at least contemporaneous intrusion with Napperby Gneiss dated at 1800-1500 m.y. on muscovite and whole-rock Rb-Sr (L P Black, BMR, pers. comm., 1975). Therefore, Harverson Granite probably Middle Proterozoic.|16-MAY-23
24307|Harverson Granite|Proposed publication|1. 'Geology of NW Arunta Block, NT' - BMR Publication. 2. 'Stratigraphic definitions in the Arunta Block' - BMR microfiche Report.|16-MAY-23
24307|Harverson Granite|Defn Reference|80/20787|16-MAY-23
24307|Harverson Granite|Reserved? Yes/No|Yes|16-MAY-23
8139|Hatches Creek Group|Name source|Hatches Creek watercourse in the south of Hatches 1:100 0000 Sheet area, Frew River 1:250 000 Sheet area.|16-MAY-23
8139|Hatches Creek Group|Unit history|Named by Sullivan (1953 - Geology of Australian Ore Deposits, AIMM, 1, 322-6), and Hossfeld (1954 - Trans Roy. Soc. S.Aust, 77, 103-61); name retained, but usage slightly modified, by Smith & others (1961 - BMR Report 58) and Ryan (1961 - BMR Bulletin 6), whose usage is followed in this definition. However, the Hatches Creek Group has not previously been subdivided into formally named constituent units.|16-MAY-23
8139|Hatches Creek Group|Constituents|The Hatches Creek Group is subdivided into 3 new subgroups, 20 new formations, and 2 new members. 7 formations are assigned to the Ooradidgee Subgroup (lowest of the three subgroups) - Epenarra Volcanics, Edmirringee Volcanics, Rooneys Formation, Kurinella Sandstone, Taragan Sandstone, Treasure Volcanics, and Mia Mia Volcanics; 7 formations are assigned to the Wauchope Subgroup (the middle subgroup) - Unimbra Sandstone, Yeeradgi Sandstone, Newlands Volcanics, Arabulja Volcanics, Coulters Sandstone, Frew River Formation, and Kudinga Basalt; and 6 formations are assigned to the Hanlon Subgroup (uppermost) - Errolola Sandstone, Alinjabon Sandstone, Lennee Creek Formation, Canulgerra Sandstone, Vaddingilla Formation, and Yaddanilla Sandstone. The Kurinelli Sandstone of the Ooradidgee Subgroup includes two new members - Endurance Sandstone Member and Warnes Sandstone Member. Contacts between the formations are generally conformable, although some local unconformities have been recognised within the Hatches Creek Group. The Wauchope Subgroup contains 2 region-wide ridge-forming formations - the Unimbra Sandstone at the base, and the Coulters Sandstone in the middle - between the above which are relatively recessive formations. The formations of the Ooradidgee Subgroup, underlying the Unimbra Sandstone, are partly lateral facies equivalents of one another, and are not as extensive as those of the Wauchope Subgroup. The formations of the Hanlon Subgroup form a layer-cake stratigraphy, as do those of the Wauchope Subgroup, but have a more restricted distribution.|16-MAY-23
8139|Hatches Creek Group|Extent|Forms most of the Davenport and Murchison Ranges, cropping out in northern and central Bonney Well, southwestern Frew River, northeastern (and also northwestern) Barrow Creek, and northwestern Elkedra 1:250 000 Sheet areas.|16-MAY-23
8139|Hatches Creek Group|Thickness range|Maximum probably at least 10 000 m.|16-MAY-23
8139|Hatches Creek Group|Lithology|Ridge-forming cross-bedded quartz arenite, feldspathic/lithic quartz arenite, and minor conglomeratic arenite, and recessive basaltic and felsic lavas and pyroclastics, friable arenite, siltstone, shale and minor carbonates.|16-MAY-23
8139|Hatches Creek Group|Relationships and boundaries|Unconformable on the Warramunga Group in the north; base not seen elsewhere. Intruded by mainly sill-like bodies of dolerite/gabbro and granophyre (which may be comagmatic with volcanics within the Hatches Creek Group), and by plutons of Devils Marbles Granite, Elkedra Granite and unnamed granite which postdate the main deformation of the Hatches Creek Group.|16-MAY-23
8139|Hatches Creek Group|Age reasons|Younger than 1870 m.y. - U-Pb zircon age for volcanics in the unconformably underlying Warramunga Group. Older than 1640m.y. - Rb-Sr whole-rock approximate age for the Elkedra Granite, which intrudes the Hatches Creek Group.|16-MAY-23
8139|Hatches Creek Group|Defn author|Blake D.H., Stewart A.J., Sweep I.P., Wyche S., 1985|16-MAY-23
8139|Hatches Creek Group|Proposed publication|BMR Report 257|16-MAY-23
8139|Hatches Creek Group|Comments|Remarks: The Hatches Creek Group, as described by Hossfeld (1954), comprises rocks he had previously assigned to the Hatches Creek Series and the Top Series (in AGGSNA, 1941 - Rep. For period ended 31 December 1940). Smith & others (1961) extended the Group to include Hossfeld's Bottom Series which previously was considered to underlie the Hatches Creek Series unconformably (Hossfeld, 1954; AGGSNA, 1941), but was found by Smith & others to be part of the same concordant and generally conformable sequence. In the new stratigraphic nomenclature, Hossfeld's Bottom Series and Top Series are part of the Ooradidgee Subgroup, and his Hatches Creek Series corresponds to parts of both the Ooradidgee and Wauchope Subgroups.|16-MAY-23
8139|Hatches Creek Group|Defn Reference|86/25362|16-MAY-23
8139|Hatches Creek Group|Status|1|16-MAY-23
27290|Hayes Metamorphic Complex|Name source|John Hayes Rockhole in the northeast of Undoolya GR 5750-331978.|16-MAY-23
27290|Hayes Metamorphic Complex|Constituents|The Hayes Metamorphic Complex consists of an unnamed unit of metasediment, Emily Gap schist (new name), Teppa Hill metamorphics (new name), Sadadeen Range gneiss (new name) and an unnamed unit of calc-silicate rock.|16-MAY-23
27290|Hayes Metamorphic Complex|Type section locality|Type locality of each component of the Hayes Metamorphic Complex is given elsewhere.|16-MAY-23
27290|Hayes Metamorphic Complex|Extent|Crops out near Alice Springs in Alice Springs 1:100 000 Sheet area over an area about 35 km east-west by about 10 km north-south.|16-MAY-23
27290|Hayes Metamorphic Complex|Relationships and boundaries|The Complex is unconformably overlain by the Iwupataka Metamorphic Complex and the Heavitree Quartzite. Dolerite dykes of the Stuart Dyke Swarm intrude the Complex. The Alice Springs Granite (new name) and the Jessie Gap gneiss (new name) may intrude the Complex.|16-MAY-23
27290|Hayes Metamorphic Complex|Identifying features|Reason for proposed name: Crystalline basement to the Iwupataka Metamorphic Complex (new name).|16-MAY-23
27290|Hayes Metamorphic Complex|Age reasons|The Hayes Metamorphci Complex is older than the Late Proterozoic overlying Heavitree Quartzite and the intruding dolerite dykes. The Alice Springs Granite and the Jessie Gap gneiss may have been emplaced or partly intruded into the Hayes Metamorphic Complex at about 1080 m.y. (the age of the migmatite event which affects the southwestern Arunta Block). The component units of the Hayes Metamorphic Complex are thought to have been metamorphosed during the Chewings Phase of deformation at about 1620 +/- 70 m.y.|16-MAY-23
27290|Hayes Metamorphic Complex|Proposed publication|Geological report on 1:100 000 scale mapping of southeastern Arunta Block, Alice Springs 1:250 000 Sheet area Northern Territory, by R D Shaw et al.  BMR Microfiche report in prep.|16-MAY-23
27290|Hayes Metamorphic Complex|Defn Reference|80/20787|16-MAY-23
27290|Hayes Metamorphic Complex|Reserved? Yes/No|Yes|16-MAY-23
8199|Hayward Creek Formation|Name source|Hayward Creek in the Tennant Creek 1:250 000 Sheet area, latitude 19o12'S, longitude 134o09'E.|16-MAY-23
8199|Hayward Creek Formation|Type section locality|From GR 410883 to GR 408883. Here the pebbly lithic sandstone and conglomerate of the Blanche Creek Member passes upward into medium grained clean quartz sandstone (orthoquartzite) about 1000 m thick. The basal part of the quartz sandstone is torrentially cross-bedded on a small scale and shows a few symmetrical ripple marks. In the lower half of the sandstone there are a few pebbly beds, 15-30 cm thick, of subrounded white quartz and pink and grey silicified orthoquartzite, 3-4 cm across, in an orthoquartzite matrix; red jasper pebbles form about 1 percent of the rock. In the upper half, the grain size decreases; pebbles are less abundant and smaller, and the sandstone is fine to medium-grained. The topmost 2000 m at the type section locality consists of cream to red, silicified, clean quartz sandstone and feldspathic sandstone. It is thin to thick-bedded, flaggy to massive, and is commonly cross-bedded.|16-MAY-23
8199|Hayward Creek Formation|Extent|Constitutes a large part of the Whittington and the Short Ranges, Tennant Creek 1:250 000 Sheet area, and it also crops out in the northwest corner of the Sheet area. There is an isolated outcrop 8 km southwest of No. 11 Bore and others northeast and northwest of Meerie Waterhole.|16-MAY-23
8199|Hayward Creek Formation|Thickness range|Ranges from about 3000 m in the southern part of the Whittington Range to about 6000 m in the Short Range|16-MAY-23
8199|Hayward Creek Formation|Lithology|The formation consists of clean quartz sandstone (orthoquartzite) and feldspathic sandstone. The basal 500 m includes a few pebbly beds; in part it is cross-bedded and ripple-marked. The Blanche Creek Member of pebbly sandstone and conglomerate forms the base of the formation.|16-MAY-23
8199|Hayward Creek Formation|Relationships and boundaries|Overlies the Early Proterozoic Warramunga Group locally with slight angular unconformity, and is overlain conformably by the Whittington Range Volcanics.|16-MAY-23
8199|Hayward Creek Formation|Age reasons|By assumed correlation of Tomkinson Creek Beds with Hatches Creek Group, late Early Proterozoic to Early Carpentarian.|16-MAY-23
8199|Hayward Creek Formation|Proposed publication|see references under Mendum and Tonkin; Dodson and Gardener|16-MAY-23
8199|Hayward Creek Formation|Name first published by|Kennewell P.J., 1978|16-MAY-23
8223|Heavitree Formation|Name source|The Heavitree Formation was first named the Heavitree Quartzite after Heavitree Gap by Joklik (1955). The four formal members of the Heavitree Formation are named after Undoolya, Temple Bar and Fenn gaps, and Mount Blatherskite (Stewart et al 1980).|16-MAY-23
8223|Heavitree Formation|Unit history|Heavitree Gap Quartzite or No. 1 quartzite of Chewings (1928), No. 1 Ridge quartzite (Ward 1925) and Heavitree Range quartzite and Heavitree quartzite (Madigan 1932). These names are no longer in use. The change from Heavitree Quartzite to Heavitree Formation has been initiated due to the recognition that the rocks of the unit are silicified sandstone rather than a quartzite.|16-MAY-23
8223|Heavitree Formation|Constituents|Blatherskite Quartzite Member, Fenn Gap Conglomerate Member, Temple Bar Sandstone Member, Undoolya Siltstone Member.|16-MAY-23
8223|Heavitree Formation|Geomorphic expression|Prominent ridges that can extend for several 100s of kms.|16-MAY-23
8223|Heavitree Formation|Type section locality|The type Area includes the cliffs west of Ingwallumum Gap (Spring Gap) at GDA94 53K 524150mE 7247050mN in ILLOGWA CREEK|16-MAY-23
8223|Heavitree Formation|Extent|Heavitree Formation crops out over a distance of ~ 800 km east-west along the northern margin of the Amadeus Basin. The formation forms an upstanding erosional strike ridge particularly along the upturned edge of the MacDonnell homocline in the MacDonnell Ranges. The less silicified portion of the unit is isolated to the Limbla Cliffs.|16-MAY-23
8223|Heavitree Formation|General description|Heavitree Formation crops out almost continuously over a distance of ~ 800 km east-west along the contemporary northern margin of the Amadeus Basin, where it forms the majority of the prominent ridges.|16-MAY-23
8223|Heavitree Formation|Thickness range|100-300 m. Has been reported to be as thick as 440m at Ellery Creek, however, this is likely complicated by folding (Madigan 1932, Prichard and Quinlan 1962).|16-MAY-23
8223|Heavitree Formation|Lithology|Fine-, medium- or coarse-grained, planar and cross-bedded, variably feldspathic quartzose sandstone, pink, grey, pinkish-brown, purple or white weathering, and rare laminated mudstone or conglomerate intervals. Low angle sigmoidal cross-bed sets range from 1-10 m thick are distinctive and are characterised by three types of internal bedding: (a) primary erosional bedding surfaces; (b) sigmoidal foreset surfaces with (c) steeper cross-bed surfaces within them (Lindsay 1999). Large-scale planar and trough cross-beds area also common. Additional sedimentary structures include a variety of ripple mark types, and occasional herringbone cross-stratification.|16-MAY-23
8223|Heavitree Formation|Depositional environment|High-energy, open shelf-like tidal setting in which currents were alternately asymmetric and unidirectional (Lindsay 1999). Alternatively, Plummer (2015) suggested that the depositional setting was predominantly a fluvial-dominated catchement cluster that discharged through a deltaic system into a central shallow depocentre. This depocentre had marine-influences via a narrow seaway.|16-MAY-23
8223|Heavitree Formation|Fossils|None observed in type area, however possible trace fossils similar to Skolithos were reported by Lindsay (1991) from probable tidally influenced sandstones from the Heavitree Formation in the northeast of the Amadeus Basin. These were interpreted by Lindsay (1999) to be 'burrow-like' structures which are inorganic and likely the result of water-escape.|16-MAY-23
8223|Heavitree Formation|Diastems or hiatuses|primary erosional bedding surfaces between cycles.|16-MAY-23
8223|Heavitree Formation|Relationships and boundaries|Conformable, gradational contact with the overlying Bitter Springs Group. Ingwallamum granite (Whelan et al in prep), granitic gneiss, migmatite and mafic schist of the Arunta Region basement are exposed within the section but an exposed contact with the overlying Heavitree Formation was not observed.|16-MAY-23
8223|Heavitree Formation|Identifying features|These massive sandstones in fact range from 1-10 m thick and comprise low-angle, sigmoidal cross-bed sets.|16-MAY-23
8223|Heavitree Formation|Structure and Metamorphism|Part of the type area is on the southern limb of a shallowly dipping, northwest plunging anticline and the section is cross-cut by a northwest-trending fault. This apparently resulted in a partial repetition of the succession. Overall the Heavitree Formation has been significantly folded and faulted throughout the basin causing varying degrees of silicification of the unit.|16-MAY-23
8223|Heavitree Formation|Age reasons|Detrital zircon analysis suggests a maximum depositional age of 1050 to 1000 Ma (Camacho et al 2002, Maidment 2005, Maidment et al 2007; Kositcin et al 2014). It is thought that the Heavitree Formation sits in the Cryogenian subdivision of the Neoproterozoic (e.g. Grey 2005).|16-MAY-23
8223|Heavitree Formation|Correlations|The sedimentary rocks exposed in the type area show little evidence of silicification compared the members at Heavitree Gap. It is therefore difficult to directly correlate the  sequences in the northeastern Amadeus with the  formally defined, but strongly silicified members. Lindsay (1999) divided the Heavitree Formation at Heavitree Gap into four sequences, these likely correlate with the four formal members recognised at Heavitree Gap. Heavitree Formation is interpreted to be correlative with the Dean Quartzite of the southwestern Amadeus Basin; Vaughan Springs Quartzite of the Ngalia Basin; Amesbury Quartzite and Yakah beds of the southwestern and southeastern Georgina Basin respectively and Stanovos Quartzite of Irindina Province, Arunta Region (Munson et al 2013 and references therein). Possibly correlates with the Kulail Sandstone, southwestern Amadeus Basin, in part.|16-MAY-23
8223|Heavitree Formation|Alteration and Mineralisation|Gold mineralisation within deformed Heavitree Formation in White Range area at the Arltunga Goldfield and Heavitree Formation/Bitter Springs Formation at Winneke goldfield. Gold mineralisation is mainly basement rocks of the Arunta Region however some is found in overlying Heavitree Formation (Edgoose 2013). The Heavitree Formation-Gillen Formation succession has also been identified as a petroleum system and has been proven as a sub-economic resource of gas/helium in Magee -1 (Marshall 2003).|16-MAY-23
8223|Heavitree Formation|Geophysical Expression|Not known.|16-MAY-23
8223|Heavitree Formation|Defn author|VJ Normington, N Donnellan 11-FEB-2016.|16-MAY-23
8223|Heavitree Formation|References|Camacho A, Hensen B and Armstrong R, 2002. Isotopic test of a thermally driven intraplate orogenic model, Australia. Geology 30, 887-890. **Chewings C, 1928. Further notes on the stratigraphy of central Australia. Transactions of the Royal Society of South Australia 52, 62-81. **Edgoose C, 2013. Amadeus Basin: in Ahmad M and Munson  TJ (editors) 'Geology and mineral resources of the Nothern Territory; Special Publication 5', Northern Territory Government. **Grey, K. 2005. Ediacaran palynology of Australia. Association of Australasian Palaeontologists, Memoir 31. **Jöklik GF, 1955. The geology of the mica fields of the Harts Range, central Australia. Bureau of Mineral Resources of Australia, Bulletin 26. **Kositcin N, Whelan JA, Hallett L and Beyer EE, 2014. Summary of results. Joint NTGS-GA geochronology project: Amadeus Basin, Arunta Region and Murphy Province, July 2012-June 2013. Northern Territory Geological Survey, Record 2014-005. **Lindsay JF, 1991. New evidence for ancient metazoan life in the Late Proterozoic Heavitree Quartzite, Amadeus Basin, central Australia: in Korsch RJ and Kennard JM (editors) 'Geological and geophysical studies in the Amadeus Basin, central Australia'. Bureau of Mineral Resources, Australia, Bulletin 236, 7-32. **Lindsay JF, 1999. Heavitree Quartzite, a Neoproterozoic (ca 800-760 Ma), high-energy, tidally influenced, ramp association, Amadeus Basin, central Australia. Australian Journal of Earth Sciences 46, 127-139. **Madigan CT, 1932. The geology of the western MacDonnell Ranges, central Australia. Quarterly Journal of the Geological Society of London 88, 672-711. **Maidment DW, 2005. Palaeozoic high-grade metamorphism within the Centralian Superbasin, Harts Range region, central Australia, Australian National Univeristy Canberra. **Maidment DW, Williams IS and Hand M, 2007. Testing long-term patterns of basin sedimentation by detrital zircon geochronology, Centralian Superbasin, Australia. Basin Research 19, 355-360. **Marshall T, 2003. Petroleum systems and source rocks in the Amadeus Basin, Northern Territory. Petroleum Exploration Society of Australia, Queensland Branch Symposium, 37-43. ** Munson TJ, Kruse PD and Ahmad M, 2013. Centralian Superbasin: in Ahmad M and Munson  TJ (editors) 'Geology and mineral resources of the Nothern Territory; Special Publication 5', Northern Territory Government. **Normington VJ, Donnellan N and Edgoose C, in prep. Characterisation of the Neoproterozoic stratigraphy of the northeast Amadeus Basin, Northern Territory. : in Northern Territory Geological Survey R . **Plummer P, 2015. Heavitree Quartzite, Amadeus Basin: it's within the Centralian Superbasin. Annual Geoscience Exploration Seminar (AGES) 2015. Record of abstracts. NTGS Record 2015-002. **Stewart AJ, Shaw RD, Langworthy AP, Warren RG, Allen AR and Clarke AB, 1980. Stratigraphic definitions of named units in the Arunta Block, Northern Territory, BMR Report 216, Bureau of Mineral Resources. **Prichard CE and Quinlan T, 1962. The geology of the southern half of the Hermannsburg 1:250 000 sheet. BMR Report No. 61. Bureau of Mineral Resources Geology and Geophysics. **Ward LK, 1925. Notes on the geological structures of South Australia. Transactions of the Royal Society of South Australia 49, 34-61. **Whelan JA, Webb G and Close DF, in prep. Limbla Special, Northern Territory. 1:100 000 geological map series 5950. Northern Territory Geological Survey, Darwin.|16-MAY-23
8256|Helen Springs Volcanics|Name source|Helen Springs property in north-central HELEN SPRINGS and south-central BEETALOO.|16-MAY-23
8256|Helen Springs Volcanics|Geomorphic expression|Bold mesa outcrops, low hills, creek-bed exposures and as pebble and cobble rubble.|16-MAY-23
8256|Helen Springs Volcanics|Type section locality|234.9-242.2m depth in cored drillhole NTGS96/1 (GRMV214640 HELEN SPRINGS; lat. 18'24'55"S, long. 134'14'40"E); see also Muckaty Sandstone Member (below). Core stored at NTGS Core Library, Darwin.|16-MAY-23
8256|Helen Springs Volcanics|Extent|Localised outcrop on Tennant Creek Inlier in TENNANT CREEK and HELEN SPRINGS; subsurface continuation probable in some adjoining sheet areas.|16-MAY-23
8256|Helen Springs Volcanics|Thickness range|At least 36m (exclusive of Muckaty Sandstone Member) in bore at Muckaty homestead (Randal 1973).|16-MAY-23
8256|Helen Springs Volcanics|Lithology|Intensely weathered and lateritised tholeiitic basalt; includes basal sandstone and conglomerate of Muckaty Sandstone Member (below).|16-MAY-23
8256|Helen Springs Volcanics|Relationships and boundaries|Undifferentiated volcanic portion of unit rests conformably on basal Muckaty Sandstone Member, which in turn overlies with angular unconformity a variety of folded Palaeo- and Mesoproterozoic units of the Tennant Creek Inlier. Volcanics disconformably overlain by Gum Ridge Formation and Montejinni Limestone.|16-MAY-23
8256|Helen Springs Volcanics|Structure and Metamorphism|Typically flat-lying.|16-MAY-23
8256|Helen Springs Volcanics|Age reasons|Early Cambrian or possibly slightly older, based on directly overlying early Middle Cambrian Gum Ridge Formation and Montejinni Limestone.|16-MAY-23
8256|Helen Springs Volcanics|Correlations|Antrim Plateau Volcanics (Traves 1955; modification of Antrim Plateau Basalts of David (1932)) beneath Ord, Daly and western Wiso Basins, Nutwood Downs Volcanics (Dunn 1963) beneath northern Georgina Basin; possibly Peaker Piker Volcanics (Smith & Roberts 1963) and Colless Volcanics (Carter et al. 1961; Carter & opik 1961) beneath northeastern Georgina Basin.|16-MAY-23
8256|Helen Springs Volcanics|References|CARTER, E.K., BROOKS, J.H. & WALKER, K.R., 1961- The Precambrian mineral belt of north-western Queensland. Bureau of Mineral Resources, Australia, Bulletin 51.  **CARTER, E.K. & OPIK, A.A., 1961- Lawn Hill - 4-mile geological series. Bureau of Mineral Resources, Australia. **DAVID, T.W.E., 1932- Explanatory notes to accompany a new geological map of the Commonwealth of Australia. Council for Scientific and Industrial Research, Sydney. **DUNN, P.R., 1963- 1:250000 geological series explanatory notes. Hodgson Downs, N.T. Bureau of Mineral Resources, Australia.**NOAKES, L.C. & TRAVES, D.M., 1954- Part III. Outline of the geology of the Barkly region. Commonwealth Scientific and Industrial Research Organization, Australia, Land Research Series 3, 34-41. **RANDAL, M.A., 1973- Groundwater in the northern Wiso Basin and environs, Northern Territory. Bureau of Mineral Resources, Australia, Bulletin 123.  **SMITH, J.W. & ROBERTS, H.G., 1963- 1:250000 geological series explanatory notes. Mount Drummond, N.T. Bureau of Mineral Resources, Australia. **TRAVES, D.M., 1955- The geology of the Ord-Victoria region, Northern Territory. Bureau of Mineral Resources, Australia, Bulletin 27.|16-MAY-23
8293|Hermit Creek Metamorphics|Type section locality|Auxiliary reference section: Good exposure along the base of an escarpment. The section lies in overturned, steeply dipping strata between 130o26'15"E, 14o11'09"S and 130o24'59"E, 14o12'02"S and typifies the known lithologies, although primary igneous textures are better preserved than is normally the case, and the section does not expose the entire sequence. A further reference locality for high grade metasediments illustrating preserved bedding lies at 130o33'35"E, 13o59'11"S, although outcrop at this site is poor.|16-MAY-23
8293|Hermit Creek Metamorphics|Extent|The unit's known distribution totals 60 km2 in limited areas of exposure south-southwest of Twin Peaks (Daly River 1:100 000 sheet area) as far as 2 km southwest of Buffalo Fly Hill (130o25'02"E, 14o11'30"S, Moyle 1:100 000 sheet area).|16-MAY-23
8293|Hermit Creek Metamorphics|Thickness range|The section totals approximately 2350 m. The lower sediment member is 700 m thick overlain by 850 m of basalts with basal dolerites, then a further 800 m of sediments. The total thickness of the unit is not known but it may be up to twice that of this section.|16-MAY-23
8293|Hermit Creek Metamorphics|Identifying features|Revision of old terms: This unit (defined by Walpole, Crohn, Dunn and Randall, 1968: Geology of the Darwin-Katherine region, Northern Territory, BMRGGA Bulletin No. 82) involves much less than was originally included in the unit, much of it now forming the Quartz Knob Metamorphics. This is essentially a division of the old unit also providing a good auxiliary section.|16-MAY-23
8293|Hermit Creek Metamorphics|Age reasons|The Buffallo Fly Hill granodiorite (informal name for 1840 Ma granitoid) intrudes the Hermit Creek Metamorphics subsequent to the second deformational event and it is therefore somewhat older than late lower Proterozoic. It may be coeval with some of the older units in the Pine Creek Geosyncline and is thought to be early or middle lower Proterozoic.|16-MAY-23
24310|Hill of Leaders Granite|Name source|Hill of Leaders tungsten mine at GR 630535, Ooradidgee 1:100 000 Sheet area, Bonney Well 1:250 000 Sheet area.|16-MAY-23
24310|Hill of Leaders Granite|Type section locality|In vicinity of the Hill of Leaders mine (latitude 20o18'00"S, longitude 134o28'00"E), around GR 630535, where the unit is well exposed as tors and spheroidal boulders.|16-MAY-23
24310|Hill of Leaders Granite|Extent|Northeastern part of Bonney Well 1:250 000 Sheet area (Bonney and Ooradidgee 1:100 000 Sheet areas).|16-MAY-23
24310|Hill of Leaders Granite|Lithology|Grey medium to coarse-grained muscovite-biotite granite containing abundant feldspar phenocrysts up to 5 cm across and angular to rounded fine-grained micaceous xenoliths; minor medium to coarse-grained even-grained granite, aplite, and greisen.|16-MAY-23
24310|Hill of Leaders Granite|Relationships and boundaries|Younger than 1870 m.y., the U-Pb zircon age for volcanics in the Warramunga Group. Older than 1400 m.y. - K-Ar biotite age obtained by Hurley & others (1961 - Geol. Soc. Amer. Bull. 72, 653-62).|16-MAY-23
24310|Hill of Leaders Granite|Defn author|Blake DL.H., 1985|16-MAY-23
24310|Hill of Leaders Granite|Comments|Remarks: Previously mapped as unnamed granite.|16-MAY-23
24310|Hill of Leaders Granite|Defn Reference|86/25362 p.32 Defined|16-MAY-23
26614|Hindrance Creek Sandstone|Name source|Hindrance Creek, latitude 14o11'S, longitude 132o50'E Eva Valley 1:100 000 Sheet area.|16-MAY-23
26614|Hindrance Creek Sandstone|Unit history|Previously called the Hindrance Creek Member of the Edith River Volcanics by Walpole & others (1968).|16-MAY-23
26614|Hindrance Creek Sandstone|Type section locality|Scattered outcrop centred on latitude 14o11'S, longitude 132o50'E from GR 660305 (bottom) to GR 683307 (top) Eva Valley 1:100 0000 Sheet area.|16-MAY-23
26614|Hindrance Creek Sandstone|Extent|Poorly exposed over an area about 20 km2 centred 8 km northeast of Eva Valley homestead (Eva Valley 1:100 000 Sheet area).|16-MAY-23
26614|Hindrance Creek Sandstone|Thickness range|500 m.|16-MAY-23
26614|Hindrance Creek Sandstone|Lithology|Pink medium to coarse, quartz sandstone, pebbly in places.|16-MAY-23
26614|Hindrance Creek Sandstone|Relationships and boundaries|Faulted or probable unconformable contact with underlying Tollis Formation (contact not exposed). Intruded and recrystallised by the Grace Creek Granite. Probably a basal unit of the Edith River Group, lithologically similar and probably equivalent to the Phillips Creek and Kurrundie Sandstones.|16-MAY-23
26614|Hindrance Creek Sandstone|Age reasons|Late Early Proterozoic (1780-1650 m.y.) as the Group unconformably overlies the Cullen Granite Complex (1780-1730 m.y.) and is older than nearby relatively flat-lying Kombolgie Formation (1650 m.y.) which postdates the Grace Creek Granite.|16-MAY-23
26614|Hindrance Creek Sandstone|Proposed publication|Geological map commentary GEOLOGY OF THE YEURALBA REGION 1:100 000 scale|16-MAY-23
83016|Hinkler Formation|Name source|The Hinkler Formation is named after the Hinkler Bore (GDA94, 53K, 612885mE, 7887171mN), which lies approximately 25 km to the northwest of the type intersection of this unit.|16-MAY-23
83016|Hinkler Formation|Geomorphic expression|No known outcrops.|16-MAY-23
83016|Hinkler Formation|Type section locality|Drillhole NDIBK07 from down-hole depth 86.5 to 151.42 m. Collar at 641523mE 7877108mN (MGA94 zone 53) / 19.194470S 136.346112E. Drill core is stored at the NTGS core library in Alice Springs.|16-MAY-23
83016|Hinkler Formation|Description at type locality|Lower interval (from 141.26 to 151.42 m down-hole depth) of sedimentary breccia with abundant angular quartz fragments and lesser intervals of pebble-cobble conglomerate overlain by an upper interval (from 86.5 to 141.26 m down-hole depth) of massive lithic arenite, arkose, and pebble-cobble conglomerate. The transition between these intervals is gradual over around 50 cm, from thickly bedded pebble conglomerate, with minor sandstone interbeds, to moderately bedded sandstone and gravel.|16-MAY-23
83016|Hinkler Formation|Extent|Unknown. Unlikely to extend to the southwest of the type intersection location, as it is absent in other boreholes in this direction, but may extend to the northwest, north, east, and southeast.|16-MAY-23
83016|Hinkler Formation|General description|Only known in type interval. See description above.|16-MAY-23
83016|Hinkler Formation|Thickness range|Approximately 65 metres (apparent thickness only, true thickness is uncertain) in Type intersection in Drillhole NDIBK07. Variations unconstrained due to insufficient data.|16-MAY-23
83016|Hinkler Formation|Lithology|Lower interval (from 141.26 to 151.42 m down-hole depth) of sedimentary breccia with abundant angular quartz fragments and lesser intervals of pebble-cobble conglomerate overlain by an upper interval (from 86.5 to 141.26 m down-hole depth) of massive lithic arenite, arkose, and pebble-cobble conglomerate.|16-MAY-23
83016|Hinkler Formation|Relationships and boundaries|Overlain by middle Cambrian Anthony Lagoon Formation of the Georgina Basin. Kalkarindji Suite is absent. Although the nature of this contact is unknown, as drill core was not obtained until 119.5 m down the hole, the significant time gap between the deposition of the Hinkler and Anthony Lagoon formations implies that an unconformity is likely to separate these two units. The Hinkler Formation overlies Bills Formation at a sharp boundary (unconformity?) at 151.42 m (down-hole depth) that separates underlying coarse-grained sandstone of Bills Formation from overlying pebble-cobble conglomerate of the Hinkler Formation.|16-MAY-23
83016|Hinkler Formation|Identifying features|This unit is predominantly distinguished by its relatively young detrital zircon maximum depositional age (see below) and unique detrital zircon age spectrum obtained from a sample of arkosic sandstone at 134.10-136.00 m down-hole depth (Kositcin, Cross, et al., in prep). Zircon ages from this sample define a unique spectrum dominated by age peaks at 1860 Ma, 2525 Ma and 2565 Ma (Kositcin, Cross, et al., in prep). The abundant angular quartz pebbles within the lower 10 m of the Hinkler Formation are characteristic of this unit and also distinguish it from the underlying Bills Formation.|16-MAY-23
83016|Hinkler Formation|Structure and Metamorphism|Little evidence of significant ductile deformation or metamorphism. Bedding in underlying unit is relatively flat-lying.|16-MAY-23
83016|Hinkler Formation|Age reasons|The sample from 134.10-136.00 m down-hole depth in drillhole NDIBK07 returned a 207Pb/206Pb zircon maximum deposition SHRIMP age of 1652 +/- 24 Ma, which provides a maximum age for this unit (Kositcin/Cross et al. in prep). The minimum age of this unit is poorly constrained by the overlying middle Cambrian Anthony Lagoon Formation.|16-MAY-23
83016|Hinkler Formation|Correlations|The U-Pb zircon maximum deposition age obtained from this unit is similar to that of the Roadhouse Formation in drillhole NDIBK10 (Rasch, 2021). The basal conglomerate of the Roadhouse Formation is also comparable with aspects of this unit's lithology. However, intervening drillholes failed to intersect either unit, which suggests that the units were not laterally continuous. Detrital zircon spectra from each of these units differ markedly. The sample from the Roadhouse Formation is characterised by a dominant age peak at ca. 1800 Ma, with second-order peaks at ca. 1650 Ma and 2400-2500 Ma (Rasch, 2021), whereas the Hinkler Formation sample contains dominant populations at 1860 Ma, 2525 Ma and 2565 Ma, with subordinate populations at ca. 1650 Ma and 2030 Ma (Kositcin et al., in prep). This suggests that these units were not originally continuous.|16-MAY-23
83016|Hinkler Formation|Alteration and Mineralisation|No evidence of significant alteration.|16-MAY-23
83016|Hinkler Formation|Geophysical Expression|Down-hole geophysical data indicate magnetic susceptibilities of ca. 0.5?1.5 x10-3 SI and conductivity of ca. 15 micro s. No density data are available, and conductivity values are only available to down-hole depths of ~119 m. The unit is not obviously mappable in existing regional geophysical data.|16-MAY-23
83016|Hinkler Formation|Defn author|A.D. Clark 24-MAR-2022|16-MAY-23
83016|Hinkler Formation|Proposed publication|Schofield and Clark et al., (in prep). Geology of the East Tennant area, Northern Territory, journal publication.|16-MAY-23
83016|Hinkler Formation|References|S. Rasch, 2021. Dating and characterising a newly discovered sedimentary basin in the East Tennant region, unpublished BSc Honours thesis, University of Adelaide.  ** Kositcin, N., Cross A.J., et al., in prep. Geochronology of the East Tennant area, Geoscience Australia record.|16-MAY-23
8468|Hooker Creek Formation|Name source|From Hooker Creek Native Settlement, latitude 18o35'S, longitude 130o37'E, Winnecke Creek SE 52-12 1:250 000 Sheet area.|16-MAY-23
8468|Hooker Creek Formation|Unit history|Chewings (1931) included the Formation in the Winnecke Creek Tableland Formation. Milligan, Smith, Nicholas and Doutch (1966) included the formation in the Merrina Beds.|16-MAY-23
8468|Hooker Creek Formation|Type section locality|In stratigraphic drillhole BMR Green Swamp Well 6, latitude 19o20'S, longitude 132o59'E, between 24.4 and 185.9 m (Kennewell and Huyleatt, in prep.). Four cores and cuttings at 3 m intervals farom this section are stored at the BMR Core and Cuttings Laboratory, Fyshwick, ACT. The log of the type section is as follows: 24.4 to 30.5 m: Calcareous siltstone, grey, few sand grains, grades to slightly calcareous in parts, siliceous matrix.  30.5 to 57.9 m: Sandstone, white, quartzose, very fine to fine grained, subangular to subrounded, dolomitic or siliceous matrix; interbedded with siltstone, red-brown, grey-green, or white-grey, micaceous or dolomitic in parts, siliceous.  57.9 to 86.8 m: Dolomite, buff brown, finely crystalline; interbedded with siltstone, dolomitic, red to grey, micaceous in parts. 86.8 to 137.5 m: Siltstone, dolomitic to slightly dolomitic, red-brown, red, pink, or grey, micaceous; rare interbeds of dolomite, cream, very fine grained. 137.5 to 146.9 m: Dolomite, grey-white, finely crystalline.  146.9 to 185.9 m: Siltstone, dolomitic, red or buff brown, micaceous.|16-MAY-23
8468|Hooker Creek Formation|Extent|The unit is exposed over large areas of Winnecke Creek SE 52-12 1:250 000 Sheet area and exteands in the subsurface under large parts of South Lake Woods SE 53-9, Green Swamp Well SE 53-13, and Tanami East SE 52-16 1:250 000 Sheet areas. Distribution in the north Wiso Basin is not known. Its extent cannot be defined exactly, as it is impossible to separate dolomites of this formation from the Montjinni Limestone in some areas.|16-MAY-23
8468|Hooker Creek Formation|Thickness range|Maximum recorded thickness is 161.5 m in the type section BMR Green Swamp Well 6.|16-MAY-23
8468|Hooker Creek Formation|Lithology|Siltstone, dolomitic, red, laminated, bioturbated, micaceous; dolomite, white finely crystalline, hard, algal structures in parts; rare sandstone, red-brown, fine grained, silty and clayey. Typical red-brown colour in outcrop probably due to weathering.|16-MAY-23
8468|Hooker Creek Formation|Relationships and boundaries|Conformably overlies the Montejinni Limestone with a gradational contact. Conformably overlain by the Lothari Hill Sandstone with a gradational contact. May form lateral equivalent of upper part of Montejinni Limestone.|16-MAY-23
8468|Hooker Creek Formation|Age reasons|Contains a fauna including Biconulites and hyolithids; Acrotreta, Acrothele, and linguloid brachiopods; echinoderm ossicles; and Redlichia and ptychopariid trilobites. Numerous small oncolites are also present (Huleatt, in prep.). The  fauna indicates an early :Middle Cambrian (Ordian) age (J Gilbert-Tomlinson, BMR, pers. comm., 1976).|16-MAY-23
8468|Hooker Creek Formation|Proposed publication|BMR Bulletin|16-MAY-23
36768|Hull Granite Suite|Name source|Hull River, central Hull 1:100 000 mapsheet.|16-MAY-23
36768|Hull Granite Suite|Unit history|unnamed Precambrian granites (Forman 1966).|16-MAY-23
36768|Hull Granite Suite|Constituents|Imbumbunna Granite, Rowley Granophyre, Walu Granite.|16-MAY-23
36768|Hull Granite Suite|Geomorphic expression|Low outcrops and rounded hills.|16-MAY-23
36768|Hull Granite Suite|Type section locality|Type localities for the constituent units are given in their respective formal definitions.|16-MAY-23
36768|Hull Granite Suite|Extent|Central eastern Hull 1:100 000 mapsheet and southeastern Bloods Range 1:100 000 mapsheet.|16-MAY-23
36768|Hull Granite Suite|Thickness range|n/a|16-MAY-23
36768|Hull Granite Suite|Lithology|Texturally variable granites ranging from medium grained, equigranular to coarsely porphyritic with euhedral K-feldspar phenocrysts up to 3 cm in size. Mineralogy comprises quartz, K-feldspar, plagioclase, biotite, muscovite with or without epidote and garnet.|16-MAY-23
36768|Hull Granite Suite|Depositional environment|Intrusive.|16-MAY-23
36768|Hull Granite Suite|Relationships and boundaries|The Walu Granite intrudes the Mount Harris Basalt. The Rowley Granophyre and Walu Granite are crosscut by mafic dykes interpreted to belong to the ~1078 Ma Alcurra Dyke Swarm. The Imbumbunna Granite unconformably underlies the ~850 Ma Dean Quartzite.|16-MAY-23
36768|Hull Granite Suite|Age reasons|Mesoproterozoic. Pb-Pb evaporation dating of zircon yielded an age of 1075 ? 2 Ma for the Rowley Granophyre and U-Pb SHRIMP date of zircon yields an age of 1084 ? 9 Ma for the Walu Granite (Close et al, 2002)..|16-MAY-23
36768|Hull Granite Suite|Correlations|Correlated with the 1071 +/- 5 Ma Angatja Granite on Petermann Ranges 1:250 000 mapsheet (Scrimgeour et al, 1999) and other 1080-1050 Ma granites documented in the western Musgrave Block by Sun et al (1996).|16-MAY-23
36768|Hull Granite Suite|Proposed publication|Close, D.F., Edgoose, C.J., Scrimgeour, I.R., 2002. Bloods Range and Hull 1:100 000 geological special, Northern Territory Geological Survey, Explanatory notes.|16-MAY-23
36768|Hull Granite Suite|Comments|Variably deformed during the 570-530 Ma Petermann Orogeny.|16-MAY-23
36768|Hull Granite Suite|References|Close, D.F., Edgoose, C.J., Scrimgeour, I.R., 2002. Bloods Range and Hull 1:100 000 geological special, Northern Territory Geological Survey, Explanatory notes. **Forman, D.J., 1966. Bloods Range Northern Territory 1:250 000 geological series explanatory notes. Sheet (SG53-3). Bureau of Mineral Resources, Australia. **Sun, S-S., Sheraton, J.W., Glickson, A.Y. and Stewart, A.J., 1996. A major magmatic event during the 1050-1080 Ma in central Australia and an emplacement age for the Giles Complex. AGSO Research Newsletter 24. **Scrimgeour, I.R., Close, D.F. and Edgoose, C.J., 1999. Petermann Ranges Northern Territory 1:250 000 geological series explanatory notes. Sheet (SG52-7). Northern Territory Geological Survey.|16-MAY-23
41844|Ikuntji Metamorphics|Name source|Ikuntji (Haasts Bluff) community 23o27' 00" S, 131o 52' 00" E, MOUNT LIEBIG.|16-MAY-23
41844|Ikuntji Metamorphics|Unit history|Previously included within undifferentiated gneiss, schist, amphibolite, quartzite, granite, dolerite and pegmatite of the Arunta Complex  (Ranford 1969)|16-MAY-23
41844|Ikuntji Metamorphics|Geomorphic expression|Low rounded hills|16-MAY-23
41844|Ikuntji Metamorphics|Type section locality|2 km west-southwest of Round Hill at 23o 25' 31.10" S, 131o 58' 43.62" E (WGS 84), MOUNT LIEBIG.|16-MAY-23
41844|Ikuntji Metamorphics|Description at type locality|Feldspathic biotite-muscovite-quartz schist, interlayered with more quartz-rich metapsammite.|16-MAY-23
41844|Ikuntji Metamorphics|Extent|In hills between Ikuntji (Haasts Bluff) community and Belt Range, eastern MOUNT LIEBIG. Some outcrops may extend into adjacent regions of HERMANNSBURG.|16-MAY-23
41844|Ikuntji Metamorphics|Thickness range|Unknown, but likely to be greater than 250 metres.|16-MAY-23
41844|Ikuntji Metamorphics|Lithology| Variably feldspathic to quartzose muscovite-biotite schist, with lesser quartz-muscovite schist, quartzite, metapelite, amphibolite and calc-silicate rock. Rare forsterite marble and tremolite schist. Grades up into massive crystalline quartzite.|16-MAY-23
41844|Ikuntji Metamorphics|Depositional environment|Probable marine environment|16-MAY-23
41844|Ikuntji Metamorphics|Relationships and boundaries|Interpreted to unconformably overlie migmatitic gneisses of the Glen Helen Metamorphics (Warren and Shaw 1995). Intruded by Stuart Pass Dolerite (Warren and Shaw 1995). Unconformably overlain by Heavitree Quartzite.|16-MAY-23
41844|Ikuntji Metamorphics|Age reasons|late Palaeoproterozoic. SHRIMP U-Pb detrital zircon dating from quartzite within the Ikuntji Metamorphics yielded a maximum deposition age of 1656 ? 40 Ma based on the youngest six analyses (Cross et al in prep). The unit was deformed and metamorphosed during the Chewings Orogeny at 1590-1570 Ma. A unit interpreted to be metavolcanic within the Iwupataka Metamorphic Complex in ALICE SPRINGS has an age of 1615 ? 11 Ma (Zhao and Bennett 1995).|16-MAY-23
41844|Ikuntji Metamorphics|Correlations|Correlated with Lizard Schist in MOUNT LIEBIG. Has strong lithological similarities with the Ryans Gap Metamorphics of the Iwupataka Metamorphic Complex in HERMANNSBURG (Warren and Shaw 1995). Upper quartzite unit may be a correlative of the Chewings Range Quartzite in HERMANNSBURG.|16-MAY-23
41844|Ikuntji Metamorphics|Comments|Metamorphosed to middle amphibolite facies. Contains small base metal and copper deposits.|16-MAY-23
41844|Ikuntji Metamorphics|References|Cross A, Claoue-Long J, Scrimgeour IR, Close DF & Edgoose CJ, in prep. NTGS-GA Geochronology project, Report 6. Northern Territory Geological Survey, Record  **Ranford LC, 1969. Mount Liebig, Northern Territory (First Edition). 1:250 000 geological map series explanatory notes, SF52-16. Bureau of Mineral Resources, Australia. **Scrimgeour IR, Close DF & Edgoose CJ, in prep. Mount Liebig, Northern Territory (Second Edition) 1:250 000 geological map series explanatory notes, SE 52-16. Northern Territory Geological Survey, Darwin. **Stewart AJ, Shaw RD, Offe LA, Langworthy AP, Warren RG, Allen AR & Clarke DB, 1980. Stratigraphic definitions of named units in the Arunta Block, Northern Territory. Bureau of Mineral Resources, Australia, Report 216. **Warren RG & Shaw RD, 1995. Hermannsburg, Nothern Territory (Second Edition). 1:250 000 geological map series explanatory notes, SF 53-13. Australian Geological Survey Organisation, Australia, Canberra. **Zhao Jianxin and Bennett VC, 1995. SHRIMP U-Pb geochronology of granites in the Arunta Inlier, central Australia: implications for Proterozoic crustal evolution. Precambrian Research 71, 265-299.|16-MAY-23
41845|Illili Suite|Name source|Illili outstation 23o 09' 05" S, 131o 44' 00" E, MOUNT LIEBIG.|16-MAY-23
41845|Illili Suite|Unit history|Previously included within undifferentiated gneiss, schist, amphibolite, quartzite, granite, dolerite and pegmatite of the Arunta Complex (Ranford 1969) and undifferentiated gneissic granite of Ranford (1968)|16-MAY-23
41845|Illili Suite|Constituents|Warumpi Granite (Scrimgeour et al in prep), Ehrenberg Granite (Close et al in prep), Gunbarrel Granite (Close et al in prep)|16-MAY-23
41845|Illili Suite|Geomorphic expression|Prominent bouldery hills and isolated outcrops|16-MAY-23
41845|Illili Suite|Type section locality|See type localities for constituent units.|16-MAY-23
41845|Illili Suite|Extent|In hills and scattered low outcrops across northern half of MOUNT LIEBIG and MOUNT RENNIE, with an east-west extent of >250 km.|16-MAY-23
41845|Illili Suite|Lithology|Foliated to gneissic porphyritic biotite granite, less common porphyritic biotite-hornblende granite and equigranular biotite granite. Phenocrysts of K-feldspar are commonly large and rounded with locally preserved rapakivi textures.|16-MAY-23
41845|Illili Suite|Relationships and boundaries|Intrudes metasediments and felsic gneisses of the Yaya Metamorphic Complex. The Ehrenberg Granite intrudes the Russell Charnockite (Waluwiya Suite) in the Ehrenberg Range. The Warumpi Granite is intruded by an unnamed granular gabbro 10 km east-southeast of Papunya, and has intrusive contacts with ambiguous timing relationships with the Larrie Grandiorite and Papunya Igneous Complex.|16-MAY-23
41845|Illili Suite|Age reasons|late Palaeoproterozoic (1640 Ma). A sample of gneissic Warumpi Granite from 3 km east of Papunya (23o12'46.88"S 131o56'35.34"E) has a SHRIMP U-Pb zircon age of 1642 +/- 3 Ma. A sample of foliated Warumpi Granite at 23o11'34.19'S 131o43'59.88"S has a SHRIMP U-Pb zircon age of 1639 +/- 3 Ma (Cross et al in prep).|16-MAY-23
41845|Illili Suite|Correlations|Forms part of more widespread 1640-1635 Ma magmatism including Waluwiya Suite, Papunya Igneous Complex and Andrew Young Igneous Complex (Young et al 1995).|16-MAY-23
41845|Illili Suite|Comments|Granites within the suite have strong compositional and geochemical affinities with each other. They have been deformed and metamorphosed at granulite to upper amphibolite facies during the 1640-1635 Ma Liebig and 1590-1560 Ma Chewings Orogenies.|16-MAY-23
41845|Illili Suite|References|Close DF, Scrimgeour IR and Edgoose CJ, in prep. Mount Rennie, Northern Territory (Second Edition). 1:250 000 geological map series explanatory notes, SF 12-15. Northern Territory Geological Survey, Darwin. **Cross A, Claoue-Long J, Scrimgeour IR, Close DF & Edgoose CJ, in press. NTGS-GA Geochronology project, Report 6. Northern Territory Geological Survey, Record, 2004-003. **Ranford LC, 1968. Mount Rennie, Northern Territory (First Edition). 1:250 000 geological map series explanatory notes, SF52-15. Bureau of Mineral Resources, Australia. **Ranford LC, 1969. Mount Liebig, Northern Territory (First Edition). 1:250 000 geological map series explanatory notes, SF52-16. Bureau of Mineral Resources, Australia. **Scrimgeour IR, Close DF & Edgoose CJ, in prep. Mount Liebig, Northern Territory (Second Edition) 1:250 000 geological map series explanatory notes, SE 52-16. Northern Territory Geological Survey, Darwin. **Young DN, Edgoose CJ, Blake DH and Shaw RD, 1995. Mount Doreen, Northern Territory, 1:250 000 geological map seies, explanatory notes SF 52-12, Northern Territory Geological Survey, Darwin.|16-MAY-23
25690|Illoquara Sandstone|Name source|Illoquara Waterhole at AMG GR LS885080 on Home of Bullion 1:100 000 sheet (5754).|16-MAY-23
25690|Illoquara Sandstone|Unit history|Previously mapped as undifferentiated Hatches Creek Group (Smith and Milligan, 1964).|16-MAY-23
25690|Illoquara Sandstone|Geomorphic expression|Forms prominent strike-ridges and cuestas with mainly pale to white air photo tones; bedding trends are clearly visable, separated by recessive siltstone, fine-grained arenite and friable arenite beds.|16-MAY-23
25690|Illoquara Sandstone|Type section locality|In the Osborne Range on Taylor 1:100 000 sheet; base at AMG GR MS145377 (latitude 21o21'38"S, longitude 134o10'34"E); top at GR MS154388 (latitude 21o21'05"S, long 134o11'02"E). No overlying unit is ever exposed, however the nominated top of the type section is considered to represent the stratigraphically highest exposed beds.|16-MAY-23
25690|Illoquara Sandstone|Extent|Forms the main ridges of the Crawford and Osborne ranges on the Crawford (5655) and Taylor (5755) 1:100 000 sheets.|16-MAY-23
25690|Illoquara Sandstone|Thickness range|About 1300 m thick at the type section. Up to about 1200 m in the Crawford 1:100 000 sheet area.|16-MAY-23
25690|Illoquara Sandstone|Lithology|(in decreasing order of abundance): Quartz arenite: fine- to medium-grained, moderately well-sorted, medium- to thick-bedded, cross-bedded in places; Feldspathic/lithic arenite, fine- to coarse-grained, poorly to moderately well sorted, medium- to thick-bedded, cross-bedded in places; Siltstone; Minor pebbly arenite; Locally conglomeratic at base (e.g. near AMG GR MS119402). The conglomerate is polymictic containing poorly rounded and poorly sorted quartz, volcanic and quartzite pebbles in a quartz-rich, medium-grained matrix.|16-MAY-23
25690|Illoquara Sandstone|Relationships and boundaries|The Illoquara Sandstone is included in the Wauchope Subgroup of the Hatches Creek Group, of which it is the uppermost formation in the Crawford and Taylor 1:100 000 sheet areas. It probably disconformably overlies the Strzeleckie Volcanics and Tinfish Sandstone. In the northwestern Crawford Range the Illoquara Sandstone overlies the Gwynne Sandstone with probable disconformity. No overlying units are exposed.|16-MAY-23
25690|Illoquara Sandstone|Structure and Metamorphism|Tightly to isoclinally folded, steeply dipping to overturned in places, slightly refolded by open folding in the Osborne Range, faulted in places.|16-MAY-23
25690|Illoquara Sandstone|Age reasons|The maximum age of the Hatches Creek Group is considered to be Early Proterozoic (Blake and others, 1987).|16-MAY-23
25690|Illoquara Sandstone|Correlations|Possibly correlates with the Coulters Sandstone (Blake and others, 1985).|16-MAY-23
25690|Illoquara Sandstone|Category|2|16-MAY-23
21994|Illyabba Metamorphics|Name source|Illyabba Dam 133o 07'E 23o 35'S.|16-MAY-23
21994|Illyabba Metamorphics|Unit history|Previously mapped by lithology as unnamed units (Offe, 1983).|16-MAY-23
21994|Illyabba Metamorphics|Geomorphic expression|Ridge and valley terrain within the MacDonnell Range.|16-MAY-23
21994|Illyabba Metamorphics|Type section locality|Upper reaches of East Creek, GR 312400 7488700, MacDonnell Ranges 1:10 000 Sheet area.|16-MAY-23
21994|Illyabba Metamorphics|Extent|Northern MacDonnell Ranges, extending east from southeast of Brumby Bore into the Alice Springs 1:250 000 Sheet area.|16-MAY-23
21994|Illyabba Metamorphics|Lithology|Compositionally layered, migmatitically differentiated gneisses, ranging from biotite-rich to felsic (includes metagranite), amphibolite, metasediments.|16-MAY-23
21994|Illyabba Metamorphics|Relationships and boundaries|Intruded by Stuart dykes, confined by faults of Redbank Thrust Zone.|16-MAY-23
21994|Illyabba Metamorphics|Structure and Metamorphism|Strongly deformed and metamorphosed at or close to granulite facies grade, resulting in the formation of very extensive migmatites of uncertain age, before being thoroughly deformed (mylonitised) under amphibolite facies metamorphism. Complexly deformed, overprinted by fabric of Redbank Thrust Zone.|16-MAY-23
21994|Illyabba Metamorphics|Age reasons|Affected by high-grade metamorphism, probably Strangways metamorphism, includes granite similar to granite in the Narwietooma Metamorphic Complex, older than the Redbank Thrust Zone (at about 1450 ma, Shaw & Black, 1992).|16-MAY-23
21994|Illyabba Metamorphics|Correlations|May be deformed equivalent of Bunghara Metamorphics.|16-MAY-23
21994|Illyabba Metamorphics|Defn author|R.D. Shaw & R.G. Warren, 22 May 1991.|16-MAY-23
21994|Illyabba Metamorphics|Comments|This 'definition' is missing the details of references mentioned in the synonymy and age, and shows no signs on the card of having been approved.|16-MAY-23
35319|Ilyaralona Granite|Name source|Ilyaralona Range, southeastern Hull 1:100 000 mapsheet.|16-MAY-23
35319|Ilyaralona Granite|Unit history|Previously described as unnamed Precambrian granite (Forman 1966).|16-MAY-23
35319|Ilyaralona Granite|Geomorphic expression|Low rounded hills|16-MAY-23
35319|Ilyaralona Granite|Type section locality|Best exposure 3.5 km north of Ilyaralona Range at 24? 50' 15.03 S, 129? 20' 47E (WGS 84).|16-MAY-23
35319|Ilyaralona Granite|Extent|Small area of outcrop on northern side of Ilyaralona Range|16-MAY-23
35319|Ilyaralona Granite|Thickness range|n/a|16-MAY-23
35319|Ilyaralona Granite|Lithology|Coarsely porphyritic muscovite granite|16-MAY-23
35319|Ilyaralona Granite|Depositional environment|Intrusive.|16-MAY-23
35319|Ilyaralona Granite|Relationships and boundaries|Forms part of the 1190-1140 Ma Pottoyu Granite Suite (Scrimgeour et al 1999). Granite outcrops in the vicinity of basalt associated with the Tjuninanta Formation. No obvious age relationship from outcrop evidence|16-MAY-23
35319|Ilyaralona Granite|Age reasons|Mesoproterozoic. Pb-Pb evaporation dates on zircon yield an age of 1163 +/- 4 Ma (Close et al, 2002).|16-MAY-23
35319|Ilyaralona Granite|Correlations|Geochemically similar to undivided Pottoyu Granite Suite (1190-1140 Ma) and Amputjuta Dacite (1153 +/- 3 Ma)|16-MAY-23
35319|Ilyaralona Granite|Proposed publication|Close, D.F., Edgoose, C.J., Scrimgeour, I.R., 2002. Bloods Range and Hull 1:100 000 geological special, Northern Territory Geological Survey, Explanatory notes.|16-MAY-23
35319|Ilyaralona Granite|References|Close, D.F., Edgoose, C.J., Scrimgeour, I.R., 2002. Bloods Range and Hull 1:100 000 geological special, Northern Territory Geological Survey, Explanatory notes. **Forman, D.J., 1966. Bloods Range Northern Territory 1:250 000 geological series explanatory notes. Sheet (SG53-3). Bureau of Mineral Resources, Australia. **Scrimgeour, I.R., Close, D.F. and Edgoose, C.J., 1999. Explanatory Notes for Petermann Ranges 1:250 000 mapsheet.|16-MAY-23
36767|Imbumbunna Granite|Name source|Imbumbunna Hills, central eastern Bloods Range 1:250 000 map sheet.|16-MAY-23
36767|Imbumbunna Granite|Unit history|Previously described as unnamed Precambrian granite (Forman 1966).|16-MAY-23
36767|Imbumbunna Granite|Geomorphic expression|Low, bouldery outcrop.|16-MAY-23
36767|Imbumbunna Granite|Type section locality|18.5 km northeast of Shaw Creek at location 24o 53' 24.04" S, 129o 55' 12.57" E (WGS 84).|16-MAY-23
36767|Imbumbunna Granite|Extent|Single occurrence in southeastern section of Bloods Range 1:100 000 mapsheet.|16-MAY-23
36767|Imbumbunna Granite|Thickness range|n/a|16-MAY-23
36767|Imbumbunna Granite|Lithology|Coarsely porphyritic biotite-muscovite-epidote-garnet granite. Characteristic euhedral K feldspar laths.|16-MAY-23
36767|Imbumbunna Granite|Depositional environment|Intrusive.|16-MAY-23
36767|Imbumbunna Granite|Relationships and boundaries|Forms part of the Hull Granite Suite. Overlain by ~850 Ma Dean Quartzite (basal Amadeus Basin sediments).|16-MAY-23
36767|Imbumbunna Granite|Age reasons|Mesoproterozoic. Geochemically grouped with granites of the 1090-1075 Ma Hull Granite Suite|16-MAY-23
36767|Imbumbunna Granite|Correlations|Geochemically similar to the Walu Granite (1084 +/- 9 Ma) and Rowley Granophyre (1075 +/- 2 Ma)|16-MAY-23
36767|Imbumbunna Granite|Proposed publication|Close, D.F., Edgoose, C.J., Scrimgeour, I.R., 2002. Bloods Range and Hull 1:100 000 geological special, Northern Territory Geological Survey, Explanatory notes.|16-MAY-23
36767|Imbumbunna Granite|Comments|Foliation weakly developed during 570-530 Ma Petermann Orogeny.|16-MAY-23
36767|Imbumbunna Granite|References| 98/29502 - Forman, D. J., 1966. Bloods Range Northern Territory 1:250 000 geological series explanatory notes. Sheet (SG53-3). Bureau of Mineral Resources, Australia.|16-MAY-23
42200|Inyalinga Granulite|Name source|Inyalinga outstation 23o 15' 00" S, 131o 25' 00" E, MOUNT LIEBIG|16-MAY-23
42200|Inyalinga Granulite|Unit history|Previously included within undifferentiated gneiss, schist, amphibolite, quartzite, granite, dolerite and pegmatite of the Arunta Complex  (Ranford 1969).|16-MAY-23
42200|Inyalinga Granulite|Geomorphic expression|Low to moderate rubbly hills.|16-MAY-23
42200|Inyalinga Granulite|Type section locality|6 km south of Kakalyi Bore at 23o 15' 27.43" S, 131o 33' 13.93" E (WGS84), MOUNT LIEBIG. Reference locality for interlayered pelitic and mafic granulite is at 23o 13' 28.49" S, 131o 44' 37.93" E.|16-MAY-23
42200|Inyalinga Granulite|Description at type locality|Massive cordierite-rich metapelite, interlayered with lesser calc-silicate rock and quartzite.|16-MAY-23
42200|Inyalinga Granulite|Extent|In hills across northern half of MOUNT LIEBIG, north of Belt Range and Amunurunga Range.|16-MAY-23
42200|Inyalinga Granulite|Thickness range|n/a|16-MAY-23
42200|Inyalinga Granulite|Lithology|Granulite facies calc-silicate-rock, mafic granulite, massive cordierite-rich metapelite, garnet-biotite-sillimanite metapelite, quartzite, metapsammite; minor strained biotite granite, felsic migmatite; and amphibolite.|16-MAY-23
42200|Inyalinga Granulite|Depositional environment|n/a|16-MAY-23
42200|Inyalinga Granulite|Relationships and boundaries|Parent: Yaya Metamorphic Complex (Scrimgeour et al in prep). Intruded by the Illili and Waluwiya Suites, Papunya Igneous Complex an unnamed charnockite (Scrimgeour et al in prep). Contacts with unnamed felsic gneiss are conformable to regional foliation with no clear timing relationships.|16-MAY-23
42200|Inyalinga Granulite|Age reasons|late Palaeoproterozoic. SHRIMP U-Pb dating of detrital zircons from a sample of massive cordierite pelite from the type locality gives a maximum deposition age of 1661 +/- 10 Ma, and metamorphic zircon rims have an age of 1638 +/- 10 Ma (Kinny 2002). A sample of quartzite from 23o14' 20.40" S, 131o 50' 25.82" E  has an older maximum deposition age of 1760 Ma (Cross et al in prep).|16-MAY-23
42200|Inyalinga Granulite|Correlations|No known direct correlatives, but cordierite granulites from the type locality have similar detrital zircon provenance to samples from the Alkipi Metamorphics (Kinny 2002).|16-MAY-23
42200|Inyalinga Granulite|Comments|Interpreted to be a package of calc-arenites, siltstones, sandstones, and carbonates, intruded by mafic rock and granites, that was metamorphosed to granulite facies during the 1640-1635 Ma Liebig Orogeny, and reworked at upper amphibolite facies during the 1590-1560 Ma Chewings Orogeny. Due to the degree of deformation and metamorphism and heterogeneity of rocktypes, it is possible that this unit may include rocks of significantly different ages. It can be distinguished from the Alkipi Metamorphics by the presence of calc-silicate rock, and relative abundance of mafic granulite and massive cordierite granulite.|16-MAY-23
42200|Inyalinga Granulite|References|Cross A, Claoue-Long J, Scrimgeour IR, Close DF & Edgoose CJ, in press. NTGS-GA Geochronology project, Report 6. Northern Territory Geological Survey, Record, 2004-003.Kinny PD, 2002. SHRIMP U-Pb geochronology of Arunta Province samples from the Mount Liebig and Lake Mackay 1:250 000 mapsheets. Northern Territory Geological Survey, Technical note 2002-015.Ranford LC, 1969. Mount Liebig, Northern Territory (First Edition). 1:250 000 geological map series explanatory notes, SF52-16. Bureau of Mineral Resources, Australia.Scrimgeour IR, Close DF & Edgoose CJ, in prep. Mount Liebig, Northern Territory (Second Edition) 1:250 000 geological map series explanatory notes, SE 52-16. Northern Territory Geological Survey, Darwin.Warren RG and Shaw RD 1995. Hermannsburg, Northern Territory (Second Edition). 1:250 000 geological map series explanatory notes, SF-53-13. Northern Territory Geological Survey, Darwin.|16-MAY-23
24318|Iwupataka Metamorphic Complex|Name source|Iwupataka, a nataive settlement about 38 km W of Alice Springs.|16-MAY-23
24318|Iwupataka Metamorphic Complex|Constituents|In Alice Springs 1:100 000 Sheet area they are Simpsons Gap Metasediments, Chewings Range Quartzite, Rungutjirba Gneiss and the Burt Bluff Gneiss. Other units mapped in MacDonnell Ranges and Hermannsburg 1:100 000 Sheet area have yet to be named and defined.|16-MAY-23
24318|Iwupataka Metamorphic Complex|Type section locality|Type locality of each component unit of the Iwupataka Metamorphic Complex is given elsewhere.|16-MAY-23
24318|Iwupataka Metamorphic Complex|Extent|Crop out over a west-trending length of about 100 km in the southern Arunta Block from near Simpsons Gap (Alice Springs 1:100 000 Sheet area) westwards to Ormiston Gorge (Hermannsburg 1:100 000 Sheet area).|16-MAY-23
24318|Iwupataka Metamorphic Complex|Relationships and boundaries|The sequence is unconformably overlain by the Heavitree Quartzite and intruded by dolerite dykes of the Stuart Dyke Swarm (new name). The sequence unconformably overlies the Hayes Metamorphic Complex to the east and grades into migmatite and granite to the west.|16-MAY-23
24318|Iwupataka Metamorphic Complex|Identifying features|Reason for proposed name: Name proposed to cover a sequence of rocks which unconformably overlie the Hayes Metamorphic Complex (new name).|16-MAY-23
24318|Iwupataka Metamorphic Complex|Age reasons|The sequence is older than the Late Proterozoic Heavitree Quartzite and the intruding dolerites. The metamorphism which accompanied the earliest widespread deformation of the Iwupataka Metamorphic Complex has been dated by total-rock Rb/Sr at 1620 +/- 70 m.y.|16-MAY-23
24318|Iwupataka Metamorphic Complex|Proposed publication|Geological report on 1:100 000 scale mapping of southeastern Arunta Block, Alice Springs 1:250 000 Sheet area, Northern Territory, by R D Shaw et al. BMR Microfiche report in prep.|16-MAY-23
24318|Iwupataka Metamorphic Complex|Defn Reference|80/20787|16-MAY-23
24318|Iwupataka Metamorphic Complex|Proposer|Offe L.A.|16-MAY-23
22013|Jalma Formation|Name source|Jalma Bay (latitude 13o15'S, longitude 136o00'E), Blue Mud Bay 1:250 000 map sheet area.|16-MAY-23
22013|Jalma Formation|Unit history|Plumb and Roberts (1965) included the Jalma Formation at the top of the now abandoned 'Groote Eylandt Beds'.|16-MAY-23
22013|Jalma Formation|Geomorphic expression|Lower part expressed as low rounded hills. Upper part recessive and valley-forming.|16-MAY-23
22013|Jalma Formation|Type section locality|Along Coast Range at latitude 13o31'S, longitude 135o48'E. Base at AMG NF865051 and top at AMG NF858055. This section is the only location where part of the upper recessive interval is exposed.|16-MAY-23
22013|Jalma Formation|Extent|Outcrops restricted to the Coast Range, Grindall Point and Gan Gan areas in the Blue Mud Bay 1:250 000 map sheet area.|16-MAY-23
22013|Jalma Formation|Thickness range|Complete sections only present along coast Range where the thickness varies from about 70 m to 130 m. Estimated to be about 110 m at the type section.|16-MAY-23
22013|Jalma Formation|Lithology|Main part of formation consists of brown to purple, medium-grained, thin- to medium-bedded, ferruginous sandstone. Probably pyritic at depth. Fine-grained, thin-bedded, flaggy sandstone near base. Local basal polymict cobble conglomerate south of type section. Upper very recessive unit of laminated mudstone (exposed only at type section).|16-MAY-23
22013|Jalma Formation|Depositional environment|Probably shallow marine.|16-MAY-23
22013|Jalma Formation|Relationships and boundaries|Not assigned to any group. Unconformably overlies the Coast Range Sandstone and locally the underlying Grindall Formation where the unconformity cuts to that level. At the type section the base is picked at the contact between medium-grained, thick-bedded, white, quartz-rich sandstone (Coast Range Sandstone) and recessive fine-grained, flaggy sandstone above. Actual point of contact obscured here. Overlain unconformably (regional evidence of truncation at contact) by the Balbirini Dolomite but the actual point of contact is obscured by younger cover. At the type section the top is picked below the ridge of prominent stromatolitic chert at the base of the Balbirini Dolomite.|16-MAY-23
22013|Jalma Formation|Age reasons|Poorly constrained. Late Palaeoproterozoic or early Mesoproterozoic based on its relative position in the regional sequence.|16-MAY-23
22013|Jalma Formation|Correlations|May correlate with the Mount Bonner Sandstone, which occupies a similar stratigraphic position in the Arnhem Bay 1:250 000 scale map sheet area to the north (Rawlings and others, in prep.).|16-MAY-23
22013|Jalma Formation|Defn author|Haines P.W.|16-MAY-23
22013|Jalma Formation|Proposed publication|Blue Mud Bay 1:250 000 Geological Map Series, Northern Territory, National Geoscience Mapping Accord, Explanatory Notes, SD 53-7 (Haines and others, in prep.).|16-MAY-23
22013|Jalma Formation|Category|2|16-MAY-23
22013|Jalma Formation|Defn approved by|Brakel A.T., Haines P.W.|16-MAY-23
22013|Jalma Formation|Proposer|Haines P.W.|16-MAY-23
22013|Jalma Formation|Reserved? Yes/No|Yes|16-MAY-23
80198|Jamaica Granite|Name source|Jamaica Bore (135.1779degreesE 22.8136degreesS, GDA2020) in HUCKITTA 1:250 000 mapsheet, Northern Territory.|16-MAY-23
80198|Jamaica Granite|Geomorphic expression|Isolated hills, nubbins, and pavements.|16-MAY-23
80198|Jamaica Granite|Type section locality|135.6834degreesE 22.755degreesS (GDA2020); access via private tracks.|16-MAY-23
80198|Jamaica Granite|Description at type locality|The type locality comprises a hill with two phases of deformed Jamaica Granite: a coarser-grained porphyritic phase, and a finer-grained orthogneiss phase. The coarser-grained phase has 5-10 vol% biotite, aligned 1-3 cm K-feldspar laths, and cm-scale garnet with mm-scale biotite rims. This phase of Jamaica Granite is cut by dm-scale veins, and 10-100 m-scale bodies of the finer-grained version. The finer-grained orthogneiss is a garnet-bearing migmatitic orthogneiss with melanosomes comprising sub-mm-scale biotite, plagioclase, quartz, K-feldspar, and accessory magnetite, and leucosomes comprising 1-5 mm exsolved K-feldspar, sub-mm-scale plagioclase, cm-scale poikiloblastic garnet with mm-scale random quartz inclusions, and accessory sub-mm-scale magnetite. This phase commonly has a pronounced gneissic foliation with mm-scale quartz and feldspar porphyroclasts. Centimetre-scale leucosomes are both parallel to the foliation and cross-cutting. Stretching and minor folding of leucosome layers indicate migmatitisation occurred during formation of the gneissic fabric. Garnet forms weakly deformed and oriented porphyroblasts in a matrix of stretched K-feldspar, quartz, and plagioclase.|16-MAY-23
80198|Jamaica Granite|Extent|Outcrops in the Kanandra Domain of southwestern HUCKITTA (Weisheit et al in prep) and possibly eastern ALCOOTA (Beyer et al in prep) 1:250 000 mapsheets, west of the abandoned Molyhil mine, north of Plenty and Marshall rivers and south of the Mopunga Range.|16-MAY-23
80198|Jamaica Granite|General description|Jamaica Granite is a fine- to coarse-grained, equigranular to locally porphyritic garnet+/-biotite granite and orthogneiss. The unit is locally migmatitic; it is foliated to gneissic, and locally mylonitic. Outcrops are fresh to moderately weathered. The unit was formed by partial melting of the Kanandra Metamorphics. It is one of two granites of the Alkara Suite and is distinguished from the Canefire Granite by the presence of garnet.|16-MAY-23
80198|Jamaica Granite|Lithology|Two phases of deformed granite: a coarser-grained porphyritic phase, and a finer-grained orthogneiss phase. The coarser-grained phase has 5-10 vol% biotite, aligned 1-3 cm K-feldspar laths, and cm-scale garnet with mm-scale biotite rims. This phase of Jamaica Granite is cut by dm-scale veins, and 10-100 m-scale bodies of the finer-grained version. The finer-grained orthogneiss is a garnet-bearing migmatitic orthogneiss with melanosomes comprising sub-mm-scale biotite, plagioclase, quartz, K-feldspar, and accessory magnetite, and leucosomes comprising 1-5 mm exsolved K-feldspar, sub-mm-scale plagioclase, cm-scale poikiloblastic garnet with mm-scale random quartz inclusions, and accessory sub-mm-scale magnetite. This phase commonly has a pronounced gneissic foliation with mm-scale quartz and feldspar porphyroclasts. Centimetre-scale leucosomes are both parallel to the foliation and cross-cutting. Stretching and minor folding of leucosome layers indicate migmatitisation occurred during formation of the gneissic fabric. Garnet forms weakly deformed and oriented porphyroblasts in a matrix of stretched K-feldspar, quartz, and plagioclase.|16-MAY-23
80198|Jamaica Granite|Depositional environment|Genesis: The Jamaica Granite contains abundant garnet, supporting derivation from an aluminous metasedimentary parent rock. Interpreted to have formed via melting of thickened metasedimentary crust.|16-MAY-23
80198|Jamaica Granite|Relationships and boundaries|Anatectic granite derived from partial melting of Kanandra Metamorphics, which occur as xenoliths in the granite. Intruded into Carmencita Metadolerite and Canefire Granite. It has diffuse contacts with the latter.|16-MAY-23
80198|Jamaica Granite|Identifying features|Garnet-bearing biotite granite and orthogneiss.|16-MAY-23
80198|Jamaica Granite|Structure and Metamorphism|Anatectic granite formed during a Palaeoproterozoic tectonothermal cycle. Commonly gneissic to locally undeformed; mylonitic in shear zones. Locally retrogressed to greenschist facies in shear zones.|16-MAY-23
80198|Jamaica Granite|Age reasons|LA-ICP-MS 207Pb/206Pb zircon age of 1724 +/- 6 Ma (Beyer et al 2022).|16-MAY-23
80198|Jamaica Granite|Correlations|Interpreted as co-magmatic and co-genetic with Canefire Granite, a constituent unit of the Alkara Suite, based on similar geochemical and isotopic composition, and timing of structural fabric development.|16-MAY-23
80198|Jamaica Granite|Alteration and Mineralisation|Isolated outcrops are commonly fresh and unaltered. However, locally deeply weathered, bleached, silicified, sericitised. No known associated mineralisation|16-MAY-23
80198|Jamaica Granite|Geophysical Expression|Locally non-characteristic, but often associated with irregular, patchy high magnetic responses.|16-MAY-23
80198|Jamaica Granite|Geochemistry|S-type monzogranite and minor syenogranite. ASI values from 1.05-1.99 indicating compositions that are moderately to strongly peraluminous. LREE-enriched with HREEs that vary from flat to having moderately-negative slopes and weak to moderately negative Eu anomalies. epsilonNd values of -1.58 and -4.12, with corresponding crustal model ages of 2.51 Ga and 2.32 Ga, and zircon epsilonHf values from -1.58 and -4.12 with corresponding crustal model ages of 2.51-2.32 Ga.|16-MAY-23
80198|Jamaica Granite|Defn author|Barry Reno, Anett Weisheit, Eloise Beyer, Pablo Farias (NT Department of Industry, Tourism and Trade, Northern Territory Geological Survey) 3-MAY-2022.|16-MAY-23
80198|Jamaica Granite|References|Beyer E et al, in prep. Alcoota, Northern Territory (Second Edition). 1:250 000 geological map series explanatory notes, SF53-11. Northern Territory Geological Survey, Darwin.   **Beyer EE and Whelan JA, 2021. Revising the igneous stratigraphy in the eastern Aileron Province: implications for geodynamic setting between ca 1.81-1.71 Ga. Annual Geoscience Exploration Seminar (AGES) Proceedings, Alice Springs, Northern Territory, 20-21 April 2021. Northern Territory Geological Survey, Darwin.  **Beyer EE, Whelan JA, Reno BL, Weisheit A, Thompson J, Meffre S, Huang H, and Woodhead JD, 2022. Summary of results. NTGS laser ablation ICP-MS U-Pb-Hf geochronology project: selected samples from HUCKITTA 1:250 000 mapsheet, May 2011-October 2018. Northern Territory Geological Survey, Darwin.  **Reno BL, Weisheit A, Beyer EE and PG Farias 2022. Jinka, Northern Territory. 1:100 000 geological map series explanatory notes, 6052. Northern Territory Geological Survey, Darwin.  **Weisheit A et al, in prep. Huckitta, Northern Territory (Third Edition). 1:250 000 geological map series explanatory notes, SF53-11. Northern Territory Geological Survey, Darwin.|16-MAY-23
24611|Jammine Granite|Name source|Small hill in Daly River (5070) 1:100 000 Sheet area at AMG 800545.|16-MAY-23
24611|Jammine Granite|Unit history|Previously included with the Allia Creek Granite (Randal, 1962). Inspection of the Allia Creek Granite to the south indicates that this northern body is sufficiently different to be recognised as a separate granite; the Allia Creek Granite is a strongly porphyritic, mesocratic granite containing numerous xenoliths.|16-MAY-23
24611|Jammine Granite|Type section locality|AMG 790540 (latitude 13o58'25"S, longitude 130o39'45"E). Exposed as low, bouldery pavements.|16-MAY-23
24611|Jammine Granite|Extent|Four small areas of outcrop in the extreme south of the daly River 1:100 000 sheet area immediately to the west of Muldiva Creek and east of Chilling Creek.|16-MAY-23
24611|Jammine Granite|Lithology|Inequigranular, medium-grained, tourmaline-muscovite leucogranite. Mineralogy: quartz, microcline, subordinate coarse muscovite, minor tourmaline.|16-MAY-23
24611|Jammine Granite|Age reasons|Early Proterozoic. Undated, however the non-foliatead texture and relationships (below) indicate that it is a probable late- to post-orogenic* intrusive, similar to others found in the Pine Creek Geosyncline and the Litchfield Block areas. (*1870-1800 Ma orogeny in the Pine Creek Geosyncline (Needham and others, 1980).|16-MAY-23
24611|Jammine Granite|Proposed publication|Dundas G.L., Edgoose C.J., Fahey G.M., Fahey JH.E., in prep. - Explanatory Notes (for) Daley River (5070). Northern Territory Geological Survey 1:100 000 Geological Map Series, Northern Territory Government Printer, Darwin.|16-MAY-23
24611|Jammine Granite|Unit name|Jammine granite|16-MAY-23
27291|Jennings Granitic Gneiss|Name source|Jennings Gorges (1. GR 5851-500064; 2. GR5851-504055) - 2 steep gorges in Heavitree Quartzite which overlies east margin of Jennings Granitic Gneiss.|16-MAY-23
27291|Jennings Granitic Gneiss|Type section locality|Extends along unnamed creek from GR 5750-394006 in Undoolya 1:100 000 Sheet area for 0.9 km northeastwards to GR 5751-400012 in Laughlen 1:100 000 Sheet area. Western end shows excellent exposures of migmatitic layered coarse granitic gneiss, grading eastward to agmatitic augen gneiss to porphyritic orthogneiss (or gneissic granite) containing enclaves of amphibolite at eastern end.|16-MAY-23
27291|Jennings Granitic Gneiss|Extent|1. Large body in southeast of Laughlen 1:100 000 Sheet area; just extends S. into  Undoolya  2. Separate large body in northeast of Undoolya 1:100 000 Sheet area.|16-MAY-23
27291|Jennings Granitic Gneiss|Lithology|The two large bodies consist of coarse granitic gneiss which is heterogeneous and grades into agmatitic augen gneiss and into porphyritic orthogneiss in places. Centre of eastern body of Gneiss occupied by finer-grained granitic gneiss (mapped separately). Eastern body also includes six elongate masses of quartzofeldspathic gneiss. Both eastern and western bodies contain numerous inclusions and rafts of amphibolite (included in Gneiss unit).|16-MAY-23
27291|Jennings Granitic Gneiss|Relationships and boundaries|Western margin of eastern body of Gneiss macroscopically discordant to trends in adjoining Randall Peak metamorphics. Concordantly surrounds separate large lens of Randall Peak metamorphics and another large lens of hornblende gneiss of unnamed unit pCv. Western body of Gneiss concordant with Randall Peak metamorphics to north. Intrudes small body of biotite gneiss of unnamed unit pC. Hence, Jennings Granitic Gneiss is in some places discordant with and intrusive into surrounding country rocks, elsewhere is concordant with them. Intruded by Mordor Igneous Complex. Unconformably overlain by Heavitree Quartzite to south, east and north.|16-MAY-23
27291|Jennings Granitic Gneiss|Identifying features|Reason for proposed name: Easily reacognised mass of granitic gneiss markedly different from the amphibolite-bearing Randall Peak metamorphics (name to be submitted by R D Shaw) to west.|16-MAY-23
27291|Jennings Granitic Gneiss|Age reasons|Three whole-rock samples lie on Rb-Sr isochron giving age = 1719 +/- 24 m.y., low initial 87Sr/86Sr ratio indicates this is time of crystallisation of Granitic Gneiss (contemporaneous with intrusion as granite during active metamorphism and deformation of the region, resulting in gneissic fabric).|16-MAY-23
27291|Jennings Granitic Gneiss|Proposed publication|1. 'Geological report on 1:100 000 scale mapping of southeastern Arunta Block, Alice Springs 1:250 000 Sheet area, Northern Territory' by R D Shaw et al.  BMR Microfiche Report in prep.  2. 'Stratigraphic definitions in the Arunta Block' - BMR Microfiche Report.|16-MAY-23
27291|Jennings Granitic Gneiss|Defn Reference|80/20787|16-MAY-23
27291|Jennings Granitic Gneiss|Proposer|Stewart A.J.|16-MAY-23
80340|Jericho Granite|Name source|After Jericho tungsten-copper prospect (GDA94, Zone53, 614466mE 7489498mN) in Jervois Range 1:100 000 mapsheet, Northern Territory.|16-MAY-23
80340|Jericho Granite|Unit history|Previously unnamed muscovite granite of Freeman et al (1986). Not related to informally named Jericho pegmatite.|16-MAY-23
80340|Jericho Granite|Geomorphic expression|Irregular, sharp-crested hills and bouldery outcrops in lowlands between hills|16-MAY-23
80340|Jericho Granite|Type section locality|GDA94, Zone5,3 618214mE 7490078mN  approximately 3.5 km northeast of Jericho W-Cu prospect.|16-MAY-23
80340|Jericho Granite|Extent|Discontinuous outcrop over an approximately 150 km2 area between Bonya Hills in the southwest, Johannsen Range in the north and Jervois Range to the east in Jervois Range 1:100 000 mapsheet.|16-MAY-23
80340|Jericho Granite|General description|Fine-grained, equigranular muscovite-rich granite with minor to rare biotite locally present.|16-MAY-23
80340|Jericho Granite|Lithology|Muscovite±biotite granite; leucocratic, weak gneissic layering with alternating discontinuous bands of very fine-grained quartz¿K-feldspar¿plagioclase and fine-grained K-feldspar¿quartz¿muscovite. Rare biotite largely altered to chlorite and foliated parallel to gneissic layering. Muscovite is interpreted as secondary.|16-MAY-23
80340|Jericho Granite|Depositional environment|Continental margin environment, either arc cordillera or back arc basin, or derived from melting of pre-existing crust that formed in a continental margin environment.|16-MAY-23
80340|Jericho Granite|Relationships and boundaries|Contact relationships with country rock units generally not exposed; locally contains xenoliths of biotite schist and calc-silicate rock interpreted to be Bonya Metamorphics; interpreted to intrude Mascotte Orthogneiss and Attutra Metagabbro. Intruded by tourmaline-bearing dykes of the Samarkand Pegmatite. Exact nature of unit boundaries is not possible to define due to later tectonism and Cenozoic cover.|16-MAY-23
80340|Jericho Granite|Identifying features|Strongly leucocratic with variable amounts of secondary muscovite. Moderately to strongly weathered. Foliated and locally gneissic. Locally contains coarse-grained poikilitic muscovite in a very fine grained granoblastic matrix of quartz-K-feldspar-plagioclase-biotite. Subordinate K-feldspar-phyric variant with tabular K-feldspar phenocrysts in a fine-grained matrix of quartz-K-feldspar-plagioclase-muscovite.|16-MAY-23
80340|Jericho Granite|Structure and Metamorphism|Penetrative, well-developed grain shape foliation defined by aligned mica and elongate quartz. Weak to moderate gneissic banding locally developed. Locally mylonitic and ultramylonitic proximal to shear zones. Deformed during regional high-thermal gradient amphibolite facies metamorphism.|16-MAY-23
80340|Jericho Granite|Age reasons|LA-ICP-MS 207Pb/206Pb zircon age of 1780 ± 4 Ma is interpreted to record the timing of igneous crystallisation, Beyer et al in prep.|16-MAY-23
80340|Jericho Granite|Correlations|Interpreted as co-magmatic and co-genetic with Thring and Unca granites of the Fosters Suite, Baikal Supersuite based on similar geochemical and isotopic composition, and timing of structural fabric development.|16-MAY-23
80340|Jericho Granite|Alteration and Mineralisation|Secondary muscovite variably developed. Strongly silicified in outcrops crosscut by large scale quartz veins. Localised tourmalinisation of granite adjacent to pegmatite dykes and quartz-tourmaline veins. No known mineralisation.|16-MAY-23
80340|Jericho Granite|Geophysical Expression|Irregular magnetic low and high signals; occurs in area of low gravity signal; radiometric high signal.|16-MAY-23
80340|Jericho Granite|Geochemistry|Weakly to moderately peraluminous I-type monzogranite to granodiorite.|16-MAY-23
80340|Jericho Granite|Defn author|Anett Weisheit, Barry Reno, Eloise Beyer (Department of Primary Industry and Resources, Northern Territory Geological Survey) 27-JUN-2018.|16-MAY-23
80340|Jericho Granite|Proposed publication|Weisheit A, Reno BL and Beyer EE, in review. Jervois Range Special, Northern Territory. 1:100 000 geological map explanatory notes, 6152 and part 6252. Northern Territory Geological Survey, Darwin.|16-MAY-23
80340|Jericho Granite|References|Beyer EE, Reno BL, Weisheit A, Whelan JA, Thompson JM, Meffre S and Woodhead JD, 2018. Summary of results. NTGS laser ablation ICP-MS U-Pb-Hf geochronology project: selected samples from JERVOIS RANGE 1:100 000 and TOBERMOREY 1:250 000 mapsheets, Aileron and Irindina provinces, January 2014 - December 2016. Northern Territory Geological Survey, Record 2018-001.  **Beyer EE, Reno BL, Weisheit A, Meffre S, Thompson J and Woodhead JD, in prep. Summary of results. NTGS laser ablation ICP-MS U-Pb-Hf geochronology project: selected samples from JINKA and JERVOIS RANGE 1:100 000 mapsheet areas, Aileron and Irindina Provinces, Arunta Region, March 2015 - December 2017. Northern Territory Geological Survey, Darwin. **Freeman MJ, Black LA, Offe LA, Senior BR, Shaw RD, Shergold JH, Simpson CJ, Walter MR, Warren RG, Donnellan N, Horsfall CJ, Laurie JR and Walley AM, 1986. Huckitta, Northern Territory (Second Edition). 1:250 000 geological map series, SF 53-11. Northern Territory Geological Survey, Darwin|16-MAY-23
80336|Jervois Granodiorite|Name source|Named after Jervois Range (around 626752mE 7498386mN, GDA94, Zone 53) in Jervois Range 1:100 000 mapsheet, Northern Territory.|16-MAY-23
80336|Jervois Granodiorite|Unit history|First defined by Smith et al (1963) as Jervois Granite, used by Freeman et al (1986) as Jervois Granite.|16-MAY-23
80336|Jervois Granodiorite|Geomorphic expression|Boulders, pavements, hills, isolated low outcrops.|16-MAY-23
80336|Jervois Granodiorite|Type section locality|About 5km northeast of Bonya Hill at 626259mE 7485808mN (GDA94, Zone53), access via private tracks.|16-MAY-23
80336|Jervois Granodiorite|Extent|In central area of the 1:100 000 Jervois Range mapsheet: around 626259mE 7485808mN, around 628030mE 7484950mN; in southeastern Jervois Range: around 654552mE 7462435mN; in eastern Jervois Range: around 653740mE 7486378mN (GDA94, Zone53).|16-MAY-23
80336|Jervois Granodiorite|General description|Elsewhere the granodiorite contains red-brown biotite and minor fine-grained hornblende, rare allanite; locally quartz-rich and biotite-poor; local occurrence of granodiorite with inequigranular assemblage of medium-grained plagioclase and K-feldspar in a fine-grained groundmass of quartz, biotite, and secondary muscovite; also rare porphyritic with K-feldspar up to 3cm long; rare monzodiorite with approximately equal proportions of hornblende and plagioclase with minor quartz, also medium-grained inequigranular assemblage of plagioclase-hornblende-biotite-quartz.|16-MAY-23
80336|Jervois Granodiorite|Lithology|Grey granodiorite with thin red-brown weathering rind, inequigranular assemblage of medium-grained plagioclase in a fine-grained matrix of quartz-K-feldspar-plagioclase-biotite, about 10 vol% biotite; pervasive, moderately-developed grain shape foliation; contains cm to half a metre scale, oval to elongate, microgranular mafic enclaves comprising sparse 1-5 mm plagioclase microphenocrysts in a very fine-grained matrix of foliated quartz, plagioclase, and biotite.|16-MAY-23
80336|Jervois Granodiorite|Depositional environment|Continental margin environment, either arc cordillera, back arc basin, or derived from melting of pre-existing crust that formed in a continental margin environment.|16-MAY-23
80336|Jervois Granodiorite|Relationships and boundaries|Interpreted to intrude Bonya Metamorphics (local occurrences of xenoliths; contacts are not exposed); intruded by Samarkand Pegmatite and quartz veins; interpreted to be unconformably overlain and to have a faulted contact with Georgina Basin.|16-MAY-23
80336|Jervois Granodiorite|Identifying features|Foliated granodiorite with mafic enclaves.|16-MAY-23
80336|Jervois Granodiorite|Structure and Metamorphism|Pervasive grain shape foliation affecting enclaves and granodiorite; intruded prior to regional high-thermal-gradient amphibolite facies metamorphism.|16-MAY-23
80336|Jervois Granodiorite|Age reasons|Igneous crystallisation at 1771±6 Ma (SHRIMP 207Pb/206Pb, Zhao and Bennett 1995), 1766±5 Ma (SHRIMP 207Pb/206Pb, Cross et al 2005), 1766.3±6.5 Ma (SHRIMP 207Pb/206Pb, Cross et al 2005)|16-MAY-23
80336|Jervois Granodiorite|Correlations|Interpreted to be co-magmatic and co-genetic with constituent units of the Casper Suite based on similar geochemical and isotopic composition, and timing of structural fabric development.|16-MAY-23
80336|Jervois Granodiorite|Alteration and Mineralisation|Local potassic and iron alteration, secondary muscovite and chlorite; sillicification close to major quartz veins.|16-MAY-23
80336|Jervois Granodiorite|Geophysical Expression|At type locality and in southeastern Jervois Range 1:100 000 mapsheet characterised by distinct circular non-magnetic signals with irregular, magnetic contact aureole; gravity low signal; radiometric high signal.|16-MAY-23
80336|Jervois Granodiorite|Geochemistry|I-type granodiorite, minor quartz-monzodiorite and diorite; moderately metaluminous to strongly peraluminous; high-K (calc-alkaline) and calc-alkaline; moderate to high LREE enrichment compared to the MREE and gently- to moderately-sloping HREE, pronounced negative anomalies in Nb, Ta, Sr, and P, and enrichment in some LILEs (Cs, Rb, K) but depletion in others (Sr, Ba)|16-MAY-23
80336|Jervois Granodiorite|Defn author|Anett Weisheit, Barry Reno, Eloise Beyer (Northern Territory Geological Survey) 27-JUN-2018.|16-MAY-23
80336|Jervois Granodiorite|Proposed publication|Weisheit A, Reno BL and Beyer EE, in review. Jervois Range Special, Northern Territory. 1:100 000 geological map explanatory notes, 6152 and part 6252. Northern Territory Geological Survey, Darwin.|16-MAY-23
80336|Jervois Granodiorite|References|Cross A, Claoué-Long JC, Scrimgeour IR, Ahmad M and Kruse PD 2005. Summary of results. Joint NTGS-GA geochronology project: Rum Jungle, basement to the Georgina Basin and eastern Arunta Region 2001-2003. Northern Territory Geological Survey Record 2005-006.  **Freeman MJ, Black LA, Offe LA, Senior BR, Shaw RD, Shergold JH, Simpson CJ, Walter MR, Warren RG, Donnellan N, Horsfall CJ, Laurie JR and Walley AM, 1986. Huckitta, Northern Territory (Second Edition). 1:250 000 geological map series, SF 53-11. Northern Territory Geological Survey, Darwin.  **Smith, K.G., 1963, Huckitta Northern Territory 1:250 000 geological series explanatory notes. Sheet SF/53-11., Bureau of Mineral Resources, Australia, 20pp.  **Zhao JX and Bennett VC, 1995. SHRIMP U-Pb zircon geochronology of granites in the Arunta Inlier, central Australia: implications for Proterozoic crustal evolution. Precambrian Research 71, 17-43.|16-MAY-23
22033|Jigaimara Formation|Name source|Jigaimara Point on Howard Island, Arnhem Bay 1:250 000 map sheet area (latitude 12o05'S, longitude 135o22'E; AMG: NG400640).|16-MAY-23
22033|Jigaimara Formation|Unit history|Plumb and others (1976) assigned the outcrop at Warnga Point on Elcho Island to the Elcho Island Formation, and two outcrops on Howard Island were also mapped as Elcho Island Formation by Dunnet (1965). However, most outcrops have not been previously mapped.|16-MAY-23
22033|Jigaimara Formation|Geomorphic expression|Rocky wave cut platforms.|16-MAY-23
22033|Jigaimara Formation|Type section locality|At latitude 12o14'S, longitude 135o09'30"E (AMG NG172478) on western tip of Banyan Island, Arnhem Bay 1:250 000 scale map sheet area. The approximate top of the underlying Elcho Island Formation is exposed at AMG NG223477 about 5 km east and at what is interpreted as a stratigraphically slightly lower position. The contact is covered. The outcrop at the type locality dips very gently north beneath the sea and no upper boundary stratotype can be nominated.|16-MAY-23
22033|Jigaimara Formation|Extent|Crops out at Warnga Point on Elcho Island, along the north coast of Howard and Banyan Islands, and on several small islands north and northeast of Milingimbi. A sequence of interbedded limestone, shale and dolostone with the same trilobite fauna was intersected (no core) in Arafura No. 1 ( Van Roye, 1983) in the Arafura Sea (latitude 10o27'08"S, longitude 134o03'22"E), and is tentatively considered to represent the same formation.|16-MAY-23
22033|Jigaimara Formation|Thickness range|The nearly flat-lying coastal outcrops only contain a few metres of outcrop each. A thickness of 370 m (between 3126 m and 3596 m) is tentatively assigned to formation in Arafura No. 1.|16-MAY-23
22033|Jigaimara Formation|Lithology|All outcrops are silicified and consist of white to grey-brown chert and cherty siltstone (presumably after limestone and calcareous siltstone). Outcrops are invariably brecciated to various degrees (jigsaw-fit to totally chaotic) with a siliceous matrix. Individual clasts are commonly well laminated and possible microbial laminations also present. Trilobite fossils are common but most are fragmentary.|16-MAY-23
22033|Jigaimara Formation|Depositional environment|Shallow marine, probably subtidal.|16-MAY-23
22033|Jigaimara Formation|Relationships and boundaries|Overlies the Elcho Island Formation of the Wessell Group. The actual contact is not exposed but is inferred to be a disconformity or unconformity as the Wessel Group is now interpreted to be Neoproterozoic in age (Rawlings and others, in prep.). Boundary is placed at the gap between flaggy sandstones (Elcho Island Formation) and silicified carbonates and calcareous siltstones (Jigaimara Formation). Van Roye (1983) interpret a break between the what is tentatively assigned to the Jigaimara Formation and underlying Proterozoic (possibly Elcho Island Formation) in Arafura No. 1. No overlying unit is exposed. Overlain by a 1128 m thick unnamed dolomitic unit in Arafura No. 1, which Bradshaw and others assign to the Goulburn Group. The Jigaimara Formation remains ungrouped at this stage.|16-MAY-23
22033|Jigaimara Formation|Age reasons|Middle Cambrian (Templetonian) on palaeontological (trilobites) evidence (Plumb and others, 1976).|16-MAY-23
22033|Jigaimara Formation|Correlations|On fossil evidence it correlates with the Beetle Creek Formation and its correlataives in the Georgina Basin (Plumb and others, 1976).|16-MAY-23
22033|Jigaimara Formation|Defn author|Haines P.W.|16-MAY-23
22033|Jigaimara Formation|Proposed publication|Arnhem Bay-Gove 1:250 000 Geological Map Series, Northern Territory, National Geoscience Mapping Accord, Explanatory Notes (Rawlings and others, in prep.).|16-MAY-23
22033|Jigaimara Formation|Defn approved by|Brakel A.T., Haines P.W.|16-MAY-23
22033|Jigaimara Formation|Defn Reference|90/26980; 01/31587; JO101/05; 98;29079; |16-MAY-23
22033|Jigaimara Formation|Proposer|Haines P.W.|16-MAY-23
32314|Jimbu Microgranite|Name source|From Jimbu Creek, a tributary of the Mann River, NE Mount Marumba 1:250 000 sheet area.|16-MAY-23
32314|Jimbu Microgranite|Unit history|Previously called Mann River Porphyry (Patterson, 1954), but invalid because of prior usage. Subsequently called Jimbu Granite by Roberts and Plumb (1965) and defined by Plumb & Roberts (1992).|16-MAY-23
32314|Jimbu Microgranite|Geomorphic expression|Generally recessive, with scattered outcrop of small exfoliating tors and boulders.|16-MAY-23
32314|Jimbu Microgranite|Type section locality|Plumb and Roberts (1992) nominated the McKay Dome (13o15'S and 133o58'E) as the type area.|16-MAY-23
32314|Jimbu Microgranite|Extent|Exposed in the core of three domes in the Shadforth and McKay Hills area, in northeast Mount Marumba 1:250 000 sheet area. Two of these domes have been informally named - the Shadforth Dome at 13o7'S and 134o02'E, and the McKay Dome at 13o15'S and 133o58'E. The largest area of outcrop occurs at an unnamed dome to the SW of the McKay Hills at 13o18'S and 133o45'E.|16-MAY-23
32314|Jimbu Microgranite|Lithology|Dominantly pink-green, massive, porphyritic microgranite, with lesser aplite and pegmatite granophyre veins and dykes. Porphyritic microgranite comprises K-feldspar and lesser quartz, plagioclase and ferromagnesian phenocrysts, set in a green to brown microcrystalline quartz-feldspar-chlorite groundmass. K-feldspar phenocrysts are up to 6 cm diameter (average 1.5 cm), round to tabular shaped,skeletal, and often exhibit a red albite outer margin (rapikivi texture). Quartz phenocrysts are resorbed and embayed and average ~0.5 cm diameter. Masses of fine-grained ferromagnesian minerals appear to have replaced primary ferromagnesian minerals. Aplite veins and dykes up to 0.5 m wide are composed of a similar lithology to the groundmass of the porphyry. Granophyre and pegmatite form metre-scale dykes and irregular masses at the inferred upper margin of the plutons. They comprise coarse cuneiform-textured intergrowths of K-feldspar and quartz. Large xenoliths of microgranite, with a similar mineralogy and texture to the groundmass of the porphyritic microgranite host, are locally present. Quartzose sandstone xenoliths are rare.|16-MAY-23
32314|Jimbu Microgranite|Relationships and boundaries|Intrudes various units of the Katherine River Group up to and including Gundi Sandstone. The contact is sharp, but with a narrow thermal aureole of intensified silicification and quartz veining. Field relationships in the vicinity of the domes are consistent with emplacement of the Jimbu Microgranite during deposition of the upper Gundi Sandstone, therefore predating the West Branch Volcanics (Rawlings and Page, in prep.). This is supported by the geochronology.|16-MAY-23
32314|Jimbu Microgranite|Age reasons|Palaeoproterozoic: SHRIMP U-Pb zircon dating provides a crystallisation and emplacement age of 1720 +/- 7 Ma (Rawlings and Page, in prep.).|16-MAY-23
32314|Jimbu Microgranite|Correlations|Belongs to the 'Fagan phase' of Rawlings (1994), which includes the West Branch Volcanics (Arnhem Shelf), Spencer Creek Group, Fagan and Gadabara Volcanics (Walker Fault Zone and Caledon Shelf), Tanumbirini Rhyolite (Batten Fault Zone and Bauhinia Shelf) and the Packsaddle Microgranite/Hobblechain Rhyolite (Wearyan Shelf). These units relate to a discrete phase of magmatism in the McArthur Basin, but absolute time correlation is not inferred.|16-MAY-23
32314|Jimbu Microgranite|Proposed publication|Mount Marumba Explanatory Notes (Sweet et al., 1997)|16-MAY-23
32314|Jimbu Microgranite|Comments|Roberts and Plumb (1965) assigned this unit to 'basement', citing an unconformable relationship with the overlying Katherine River Group. However, field relationships (Rawlings and Page, in prep.; Sweet et al, in prep.) are consistent with an intrusive relationship with the Katherine River Group and the unit has been redefined accordingly. The overall texture of the unit is porphyritic with a uniformly fine-grained microgranitic groundmass. Consequently, the name 'Jimbu Granite' is herein revised to 'Jimbu Microgranite' to embrace more aptly this texture.|16-MAY-23
32314|Jimbu Microgranite|Apprdate|sometime before 30-NOV-1998|16-MAY-23
32314|Jimbu Microgranite|Proposer|Rawlings D. (after Plumb and Roberts, 1992)|16-MAY-23
32314|Jimbu Microgranite|Status|1|16-MAY-23
24641|Jinduckin Formation|Name source|Jinduckin Creek, about 10 km south (upstream) of Oolloo Crossing of Daly River (Jinduckin 1:100 000).|16-MAY-23
24641|Jinduckin Formation|Unit history|Elliott Creek Formation of Noakes (1949) in part; Tipperary Limestone of Walpole (1958) in part.|16-MAY-23
24641|Jinduckin Formation|Geomorphic expression|Flat to undulating plains; outcrops infrequent, generally as low ridges of more resistant lithologies (dolomitic sandstone, ooid grainstone).|16-MAY-23
24641|Jinduckin Formation|Type section locality|243.9-579.3 m in cored drillhole NTGS 86/1, northeastern Jinduckin 1:100 000, AMG 587327 (latitude 14o09'50"S, longitude 131o23'50"E). Core stored at NTGS Core Library, Darwin.|16-MAY-23
24641|Jinduckin Formation|Extent|Outcrop in Pine Creek, Fergusson River, Katherine, Delamere, Larrimah 1:250 000; subcrop inferred in Cape Scott 1:250 000.|16-MAY-23
24641|Jinduckin Formation|Thickness range|335.4 m in type section; maximum 356.1 m in cored drillhole NTGS 83/2-2A (southwestern Tipperary 1:100 000); "396 m" (Lau, 1981) but probably closer to 355 m in percussion drillhole DB10 (south-central Tipperary 1:100 000); "370 m' (Lau, 1981) in percussion drillhole DB30A (central western Manbulloo 1:100 000). Thicknesses in cored drillholes are treated as definitive.|16-MAY-23
24641|Jinduckin Formation|Lithology|Maroon-green dolomitic-siliciclastic siltstones grading into dolomitic wavy and lenticular sandstone-siltstone interbeds; dolostones; minor cryptalgal dolostones, ooid dolograinstones and dolomitic quartz sandstones. Evaporties (principally anhydrite) common in maroon siltstones and interbeds, and some sandstones, particularly in lower half of formation. Numerous flat pebble breccias and other indications of erosive surfaces representing minor hiatuses.|16-MAY-23
24641|Jinduckin Formation|Relationships and boundaries|Apparent conformity with Tindall Limestone below, conformable gradational contact with Oolloo Dolostone above. Where not overlain by Oolloo Dolostone, the unit is commonly unconformably overlain by Cretaceous sandstones (Petrel Formation, Bathurst Island Formation). In type section, lower boundary of unit is placed at top of highest limestone in the sequence; upper boundary is placed at top of highest finely laminated dolomitic sandstone-siltstone interbeds.|16-MAY-23
24641|Jinduckin Formation|Structure and Metamorphism|Horizontal to very gently dipping; local fault-induced folding in northern Tipperary 1:100 0000.|16-MAY-23
24641|Jinduckin Formation|Age reasons|Middle Cambrian to Early Ordovician. Conodonts place uppermost Jinduckin Formation at Claravale (southwestern Fergusson River 1:100 000) within the late Warendian/Tremadoc Chosonodina herfurthi-Acodus and early Arenig Drepanodus? Gracilis - Scolopodus sexplicatus Assemblage Zones of Druce & Jones (1971; Jones, 1971; Webby and others, 1981).|16-MAY-23
24641|Jinduckin Formation|Correlations|Pander Greensand (Bonaparte Basin) and Datson Member of Ninmaroo Formation (Georgina Basin) - Jones (1971).|16-MAY-23
24641|Jinduckin Formation|First Reference|79/01359|16-MAY-23
24641|Jinduckin Formation|Proposer|Kruse P.D.; originally Randal (1962), Malone (1962)|16-MAY-23
24641|Jinduckin Formation|Status|1|16-MAY-23
26643|Jinka Granite|Name source|Jinka Plain (around 135.8762degreesE 22.6947degreesS (GDA 2020)) in Jinka 1:100 000 mapsheet, Northern Territory.|16-MAY-23
26643|Jinka Granite|Unit history|First defined by Joklik (1955); more fully defined in Shaw et al (1984) and Freeman (1986).|16-MAY-23
26643|Jinka Granite|Geomorphic expression|Isolated hills, nubbins, and pavements; commonly found near quartz and quartz breccia veins in the Jinka Plain and west of the Elua Range.|16-MAY-23
26643|Jinka Granite|Type section locality|135.8819degreesE 22.6335degreesS (GDA2020); access via private tracks.|16-MAY-23
26643|Jinka Granite|Description at type locality|Grey porphyritic biotite granite with abundant coarse-grained tabular K-feldspar phenocrysts with individual crystals up to 8 cm long and aspect ratios of 1:2 to 1:3. The groundmass is composed of fine-grained quartz-K-feldspar-plagioclase-biotite with 5-10 vol% biotite. Magmatic flow foliations are common with phenocrysts moderately to strongly aligned.|16-MAY-23
26643|Jinka Granite|Extent|Isolated outcrops east of the Mopunga Range and west of the Bonya Hills, south of the Dulcie Range and north of the Marshall River in JINKA and westernmost JERVOIS RANGE 1:100 000 mapsheets (Reno et al 2019, Weisheit et al 2019). Possibly extensive in the subsurface in that area.|16-MAY-23
26643|Jinka Granite|General description|Biotite granite: fine- to coarse-grained, porphyritic to less commonly equigranular; fresh to moderately weathered; undeformed, locally developed magmatic flow foliation; minor felsic porphyry with sparse K-feldspar phenocrysts.|16-MAY-23
26643|Jinka Granite|Lithology|Grey porphyritic biotite granite with abundant coarse-grained tabular K-feldspar phenocrysts with individual crystals up to 8 cm long and aspect ratios of 1:2 to 1:3. The groundmass is composed of fine-grained quartz-K-feldspar-plagioclase-biotite with 5-10 vol% biotite. Magmatic flow foliations are common with phenocrysts moderately to strongly aligned.|16-MAY-23
26643|Jinka Granite|Depositional environment|Genesis: Interpreted as having formed via melting of thickened crust during a period of crustal stabilisation and relaxation at the end of a regional Palaeoproterozoic tectonothermal event.|16-MAY-23
26643|Jinka Granite|Relationships and boundaries|Interpreted to include possible xenoliths of Deep Bore Metamorphics; intrudes Marshall Granite; nonconformably overlain by Neoproterozoic Mount Cornish Formation, Oorabra Arkose and Elyuah Formation of the Georgina Basin.|16-MAY-23
26643|Jinka Granite|Structure and Metamorphism|Undeformed, unmetamorphosed.|16-MAY-23
26643|Jinka Granite|Age reasons|SHRIMP 207Pb/206Pb zircon age of 1714 +/- 3 Ma interpreted as igneous crystallisation (Kositcin et al 2011)|16-MAY-23
26643|Jinka Granite|Correlations|Interpreted as co-magmatic and co-genetic with Marshall Granite, both constituent units of the Sainthill Suite, based on similar geochemical and isotopic composition, and timing of structural fabric development.|16-MAY-23
26643|Jinka Granite|Alteration and Mineralisation|Isolated outcrops are commonly fresh and unaltered. Outcrop adjacent to quartz veins and quartz vein breccias are commonly strongly silicified or K-feldspar altered. Local hematite, epidote or chlorite alteration.|16-MAY-23
26643|Jinka Granite|Geophysical Expression|Moderate-high magnetic response with rare, <1 km-sized circular to northwest-elongate magnetic high response; associated with a gravity low; high radiometric response.|16-MAY-23
26643|Jinka Granite|Geochemistry|Monzogranite and syenogranite. ASI values from 1.03?1.37 indicating compositions that are weakly to strongly peraluminous. LREE-enriched with HREEs that vary from flat to having moderately negative or positive slopes and strongly negative Eu anomalies. epsilonNd values range from -2.31 and -3.14, corresponding to crustal model ages of 2.42-2.36 Ga.|16-MAY-23
26643|Jinka Granite|Defn author|Barry Reno, Anett Weisheit, Eloise Beyer, Pablo Farias (NT Department of Industry, Tourism and Trade, Northern Territory Geological Survey) 3-MAY-2022.|16-MAY-23
26643|Jinka Granite|Comments|Revision of previous definition.|16-MAY-23
26643|Jinka Granite|References|Joklik GF, 1955. The geology and mica-fields of the Harts Range, Central Australia. Bureau of Mineral Resources, Australia, Bulletin 26.  **Freeman MJ, 1986. Huckitta, Northern Territory (Second Edition). 1:250 000 geological map series explanatory notes, SF53-11. Northern Territory Geological Survey, Darwin.   **Kositcin N, Magee CW, Whelan JA and Champion DC, 2011. New SHRIMP geochronology from the Arunta Region: 2009-2010. Geoscience Australia, Record 2011-014.  **Reno BL, Weisheit A, Beyer EE, Whelan JA and Kraus S, 2019. Jervois Range Special, Northern Territory (First Edition). 1:100 000 geological map series, 6152 and part 6252. Northern Territory Geological Survey, Darwin.  **Reno BL, Weisheit A, Beyer EE and PG Farias, 2022. Jinka, Northern Territory. 1:100 000 geological map series explanatory notes, 6052. Northern Territory Geological Survey, Darwin.  **Shaw RD, Warren RG, Offe LA, Freeman MJ and Horsfall CL, 1984. Geology of the Arunta Block in the southern part of the Huckitta 1:250 000 sheet area, central Australia. Preliminary data, 1980 survey. Bureau of Mineral Resources, Australia, Record 1984/3.  **Weisheit A, Reno BL and Beyer EE, 2019. Jervois Range Special, Northern Territory (First Edition). 1:100 000 geological map series, explanatory notes 6152 and part 6252. Northern Territory Geological Survey, Darwin.|16-MAY-23
83013|Joey Granite|Name source|Due to the lack of suitable nearby geographic names, we have named this unit following a theme of juvenile animals, given this unit?s parent unit, the Mount Lamb Suite.|16-MAY-23
83013|Joey Granite|Geomorphic expression|No known outcrops.|16-MAY-23
83013|Joey Granite|Type section locality|Drillhole NDIBK10, down-hole depth of 747.67 m to 756.01 m. Drillhole location 593827mE 7813094mN (MGA94 zone 53) / 19.775675S 135.895673E. Drill core is stored at the NTGS core library in Alice Springs.|16-MAY-23
83013|Joey Granite|Description at type locality|Light pink, medium- to coarse-grained monzogranite, comprising plagioclase, potassium feldspar, quartz, hornblende with trace zircon and tourmaline.|16-MAY-23
83013|Joey Granite|Extent|Poorly defined/unknown. Currently mapped as an elongate, 10 km-long body to the north and west of drillhole NDIBK10 (Clark et al., 2021). However, the geophysical evidence supporting this interpretation is unclear (see geophysical expression below).|16-MAY-23
83013|Joey Granite|General description|Only known at type intersection and an approximately one metre-long interval several metres above the type intersection. See description above.|16-MAY-23
83013|Joey Granite|Thickness range|Approximately 4.3 metres (true thickness) at type locality. This unit is intersected within two intervals in drill core NDIBK10. The first interval is approximately one metre, and the second interval (type interval) is approximately 8.5 metres. The true thickness of the unit in these intervals is probably around half of these intersected lengths, as the boundaries of the unit are oriented approximately 45 degrees to the drill core axis. The composite true thickness of the unit encountered in drill core NDIBK10 is approximately 4.8 metres.|16-MAY-23
83013|Joey Granite|Lithology|Medium- to coarse-grained monzogranite, comprising plagioclase, potassium feldspar, quartz, hornblende with trace zircon and tourmaline.|16-MAY-23
83013|Joey Granite|Relationships and boundaries|The Joey Granite intrudes paragneiss of the Alroy Formation, which underlies and overlies the type intersection of Joey Granite in drill core NDIBK10|16-MAY-23
83013|Joey Granite|Identifying features|This unit's light pink colour and massive, equigranular, medium-grained texture distinguish it from the more heterogeneous gneiss of the Alroy Formation.|16-MAY-23
83013|Joey Granite|Structure and Metamorphism|The unit is relatively massive and unfoliated. In thin-section, some primary minerals have been variably altered to fine-grained chlorite and white mica. In some places, the unit appears to cross-cut a well-developed solid-state fabric in the Alroy Formation, although other boundaries of the Joey Granite are sub-parallel to this fabric. We interpret that the Joey Granite postdates significant deformation and metamorphism in the Alroy Formation, but that deformation continued to some degree after, or during, the emplacement of the Joey Granite.|16-MAY-23
83013|Joey Granite|Age reasons|SHRIMP U-Pb analysis of this rock indicates that it was emplaced at 1854.2 +/- 5.3 Ma (Kositcin, Cross et al., in prep).|16-MAY-23
83013|Joey Granite|Correlations|None.|16-MAY-23
83013|Joey Granite|Alteration and Mineralisation|Minor chlorite and white mica alteration.|16-MAY-23
83013|Joey Granite|Geophysical Expression|Indistinct in regional imagery and down-hole data due to similarities with Alroy Formation.|16-MAY-23
83013|Joey Granite|Geochemistry|Only a single analysis of the Joey Granite is available. The Joey Granite has a felsic compositional range (SiO2 = 73 wt.%). Like other constituents of the Mount Lamb Suite, it is high-K (K2O =8.23 wt.%; although it also has very low Na2O, suggesting likely alteration), peraluminous (ASI = 1.43) and enrichment of light rare earth elements relative to medium and heavy rare earth elements (normalised La/Yb = 28) with relatively flat medium to heavy rare earth elements (normalised Gd/Yb = 2.5), and a pronounced negative Eu anomaly (Eu/Eu* = 0.43). Evolved whole rock Nd isotopic composition from a single sample (epsilon Nd 1854.2 Ma = -1.82).|16-MAY-23
83013|Joey Granite|Defn author|A.D. Clark 24-MAR-2022|16-MAY-23
83013|Joey Granite|Proposed publication|Schofield and Clark et al., (in prep). Geology of the East Tennant area, Northern Territory, journal publication.|16-MAY-23
83013|Joey Granite|References|Kositcin, N., Cross A.J., et al., in prep. Geochronology of the East Tennant area, Geoscience Australia record.  **Schofield and Clark et al., (in prep). Geology of the East Tennant area, Northern Territory.  **Clark, A., Highet, L., Schofield, A., Doublier, M., 2021. Solid Geology map of the East Tennant region, dataset, Geoscience Australia|16-MAY-23
24321|Johannsen Metagabbro|Name source|Johannsen's Phlogopite Mine - a well known locality in the area from which phlogopite was mined during World War II (GR 5751-079306). On the 1st Edition 1:100 0000 map (The Geology of the strangways Range Region), the form term 'Dyke Swarm' is added for clarification.|16-MAY-23
24321|Johannsen Metagabbro|Unit history|Previously mapped by Wells & others (1968) as the undivided Arunta Complex.|16-MAY-23
24321|Johannsen Metagabbro|Type section locality|The large mass of metagrabbro 2 km southwest of Johannsen's Phlogopite Mine is the type area.|16-MAY-23
24321|Johannsen Metagabbro|Extent|The dykes radiate outwards as a series of prominent ridges from a large mass 2 km southwest of Johannsen's Phlogopite Mine.|16-MAY-23
24321|Johannsen Metagabbro|Thickness range|Individual dykes are up to 100 m thick.|16-MAY-23
24321|Johannsen Metagabbro|Lithology|The metagabbro is compositionally homogeneous and total rock analysis plot in the tholeiitic field of Irvine & Barager (1971), but it is olivine normative (Allen, 1976). The primary metamorphic assemblage is plagioclase-orthopyroxene-clinopyroxene- brown green hornblende-ilmenite; although hornblende or ilmenite may be absent. Retrograde metamorphism results in green hornblende, cummingtonite, blue-green hornblende, epidote and sphene. The primary rock type is coarse-grained.|16-MAY-23
24321|Johannsen Metagabbro|Relationships and boundaries|The metagabbro dykes of the unit cut the Harry Anorthositic Gabbro and Erontonga metamorphics, and are themselves cut by the Gumtree Granite, pyroxene dolerite dykes (finer-grained) and coarse-feldspar pegmatite dykes.|16-MAY-23
24321|Johannsen Metagabbro|Age reasons|Middle Proterozoic or older. The dykes are intruded parallel to F1 axial-plane fold traces which are thought to have formed during the main regional metamorphism of the Harry Anorthositic Gabbro. The metamorphism is dated at 1800 m.y. by the incremental 40Ar-39Ar method (Allen & Stubbs, in preparation), and so the intrusive age of the Johannsen Metagabbro is postulated to be the same.|16-MAY-23
24321|Johannsen Metagabbro|Proposed publication|Stewart & others, in prep.|16-MAY-23
24321|Johannsen Metagabbro|Comments|Remarks: The Gabbro is coarser-grained than the mafic gneisses in the Erontonga metamorphics, weathers spheroidally and is much more uniform in composition.|16-MAY-23
24321|Johannsen Metagabbro|Defn Reference|80/20787|16-MAY-23
24321|Johannsen Metagabbro|Proposer|Shaw R.D., Allen A.R. (in Shaw & others, in preparation)|16-MAY-23
79262|Johnnys Creek Formation|Name source|The name is derived from East Johnny's Creek-1 well (GDA94 52J 767514mE 7323113mN).|16-MAY-23
79262|Johnnys Creek Formation|Unit history|Gorter (1982) called the unit the Johnny's Creek beds, then Ambrose (2006) formalised the name as Johnnys Creek Member but without formalising the definition of the unit. Johnnys Creek Member and Finke beds (now Wallara Formation)  have been considered equivalent (Marshall 2004). However, the Finke beds have a distinctive/discrete biostratigraphy that includes the stromatolite Baicalia burra sp., and the first occurrence of the acritarch Cerebrosphaera buicki (Grey et al 2011).|16-MAY-23
79262|Johnnys Creek Formation|Geomorphic expression|The Johnnys Creek Formation is typically exposed as recrystallised limestone ridges and recessive or low-lying intervals where the mudstone and dolostone cycles are exposed. Ridges are typically discontinuous.|16-MAY-23
79262|Johnnys Creek Formation|Type section locality|Near the Ross River Homestead GDA 94 53K 449315mE 7392047mN ALICE SPRINGS. The type section extends between an interpreted faulted contact with the underlying Gillen Formation at 53K 449315mE 7392047mN and a fault breccia at 53K 449356mE 7391572mN in ALICE SPRINGS.|16-MAY-23
79262|Johnnys Creek Formation|Description at type locality|The section consists of red, calcareous mudstone beds alternating with beds of stromatolitic dolostone or cherty dolostone. The top of the section is dominated by poorly exposed basalt.|16-MAY-23
79262|Johnnys Creek Formation|Extent|Occurs in numerous drillholes (eg Mount Winter-1, Wallara-1, Ochre Hill-1, East Johnnys Creek-1, Erldunda-1, Mount Charlotte-1, Ooraminna-1, Murphy-1 and Ayers Rock-2) in the central-western Amadeus Basin. The unit is now also described from NTGS stratigraphic drillhole BR05DD01 in the west of the basin (Ambrose et al 2010), and occurs sporadically in outcrops along the ranges of HERMANNSBERG, ALICE SPRINGS (including at Undoolya Gap, Ross River and Shannon Bore), within the Limbla Syncline, ILLOGWA CREEK, on the southern limb of the Hi Jinx Syncline and at the Pipeline Cu prospect, HALE RIVER.|16-MAY-23
79262|Johnnys Creek Formation|General description|The Johnnys Creek Formation is typically exposed as recrystallised limestone ridges and recessive or low-lying intervals where the mudstone and dolostone cycles are exposed.|16-MAY-23
79262|Johnnys Creek Formation|Thickness range|Approximately 360 m thick in type section. Edgoose (2013) reported that the Johnnys Creek Formation ranges in thickness up to about 400 m. Exposures of Johnnys Creek Formation have been reported to vary in thickness from 130 m at Ellery Creek (Prichard and Quinlan 1962, Wells et al 1967) to 380m at Ross River (Southgate 1991). In drill hole, the thickness also varies greatly. 78 m were intersected in the section in Mount Winter No. 1 well (Serra 1982), while at BR05DD01 a thickness of 384 m is suggested (after recalculations by Grey et al 2011). It is likely that 380 to 400 m is the true thickness of the Johnnys Creek Formation, as reported and observed thicknesses are consistently within this range.|16-MAY-23
79262|Johnnys Creek Formation|Lithology|The type section includes up to 13 cycles of red, generally calcareous, mudstone and layered, typically selectively chertified, pale-grey to buff limestone which is in turn overlain by 'massive' pale grey or khaki limestone. The thickly-laminated to very thinly-bedded red, calcareous mudstone cycles are up to 10 m thick. Most exposures of the red mudstone beds have diagnostic circular, white inclusions, that when tested with acid have the same effervescence as the red mudstone indicating that these patches are not accumulations of more calcareous sediments. It is not possible to identify any sedimentary structures in these sediments due to the fine-grained sand and silt component. 
The pale grey to buff limestone cycles comprise of lower boundstones with domical stromatolites overlain by planar laminated boundstones that are interpreted to comprise flat cryptomicrobial mats. The variability of the certification of the limestone cycles dictates the preservation of the stromatolites and stromatolitic laminae. Some have pink domal laminae which are likely to be unformed stromatolites or algal mat forming, while in other cycles the limestone is massive and almost completely certified. Chert nodules and concretions are common throughout the limestone as are calcite filled cracks. 
The upper part of the type section is comprised of massive pale grey to khaki limestone with minor beds of recessive, red mudstone. The limestone forms a series of strike ridges up to 35 m thick, separated by about 10 m of recessive mudstone beds. Approximately 70 m of poorly exposed, highlight weathered basalt is located between the last stromatolitic limestone and the first strike ridge of massive limestone. This part of the section is littered with carbonate scree and the green, crumbly basalt is difficult to see at first glance. The contact between the basalt and the base of the first ridge is sharp and appears to be undulating along the ridge.|16-MAY-23
79262|Johnnys Creek Formation|Depositional environment|Southgate (1991) concluded that the Johnnys Creek Formation records a cyclic progression from (1) shallow submergent; (2) semi-emergent; (3) shallow-water hypersaline lakes and playas; (4) low-relief mudflats and (5) clay pans and playas. 
The basalt of the Johnnys Creek Formation is spilitic and the extrusive origin is indicated by amygdaloidal textures and rare presence of scoria (Banks 1964, Nowland 2008). Up to 40 m of basalt has been encountered in drill holes, where the basalt is interlayered with red calcareous siltstone which displays contact features such as peperitic textures. This may be indicative that the basalt flow was either erupted onto, or was shallowly intruded into unconsolidated calcareous silt (Edgoose 2013, Nowland 2008).|16-MAY-23
79262|Johnnys Creek Formation|Fossils|Brecciated black chert in the section north of Ross River homestead contains a microbial palaeoflora (Schopf 1968). A recent geochemical and palaeontological study by Hill and Grey (in prep.) has also identified diagnostic microfossil and stromatolite assemblages.|16-MAY-23
79262|Johnnys Creek Formation|Relationships and boundaries|The contact between the underlying Loves Creek Formation and the Johnnys Creek Formation is locally conformable; however it is possible that the contact is a disconformity, considering the sharp boundary between the units (Gorter 1982). The upper contact with the Wallara Formation is a sharp erosional boundary. Also previously described is an unconformable, erosional contact with the Areyonga Formation (Ambrose 2006, Ranford et al 1965, Wells et al 1967). Erosion during the Sturtian glaciation removed a substantial amount of the Bitter Springs Group and there is an at least 200 metres relief on the unconformity underlying the Areyonga Formation (Lindsay 1993, Lindsay and Braiser 2004).|16-MAY-23
79262|Johnnys Creek Formation|Identifying features|The red calcareous mudstone is the most distinguishing  unit of the Johnnys Creek Formation. The cycles of red mudstone and buff dolostone are also a very identifiable feature, as is the presence of weathered basalt at the top of the unit, though this is not always present.|16-MAY-23
79262|Johnnys Creek Formation|Structure and Metamorphism|The Johnnys Creek Formation is typically folded and faulted, especially on the northeastern margins of the Amadeus Basin.|16-MAY-23
79262|Johnnys Creek Formation|Age reasons|The Bitter Springs Group and hence the Loves Creek Formation age is constrained to approximately 820 Ma based on geochemical correlation of the basalt with the Amata Dolerite in the Musgrave Province. No further analysis of this unit has taken place in this study, as no appropriate lithological unit was observed. The Amata Dolerite forms part of a continental flood basalt province and has been dated at ca 800 Ma (Sm-Nd whole rock + clinopyroxene + plagioclase, Zhao et al 1994, Zhao and McCullouch 1993), and 824 +/- 4 Ma (U Pb baddeleyite, unpublished data quoted in Glikson et al 1996). In-situ U-Pb dating of zircon from basalt lava in the Johnnys Creek Formation suggests an igneous crystallisation age of 767 +/- 130 Ma that is currently based on only four zircons (Thompson et al 2015). While this age is plausible on the basis of a number of independent geological considerations, it is only preliminary pending analysis of a greater number of zircons.|16-MAY-23
79262|Johnnys Creek Formation|Correlations|The Johnnys Creek Formation is correlated with the lower part of the Buldya Group of the Officer Basin, and with the lower part of the Burra Group of the Adelaide Fold Belt (Grey et al 2011, Hill et al 2011).|16-MAY-23
79262|Johnnys Creek Formation|Alteration and Mineralisation|Copper: Numerous copper occurrences in the Amadeus Basin have been associated with the volcanics of the Johnnys Creek Formation, although the mineralisation is generally expressed in overlying sediments (Edgoose 2013). 
Petroleum: Marshall et al (2007) included the Johnnys Creek Formation as part of his 2nd (or middle Neoproterozoic) Petroleum System, and the formation has been identified as a potential source rock (Munson 2014).|16-MAY-23
79262|Johnnys Creek Formation|Geochemistry|Nowland (2008) reported that basalt lavas within the Johnnys Creek Formation have been altered, but inferred that they are most likely tholeiitic and geochemically comparable to intraplate basalts. Nowland (2008) reported that these basalts generally have gentle, uniformly sloped chondrite normalised REE patterns, while the least altered samples show enrichment of LREE relative to HREE but generally flat LREE patterns. He concluded that melt compositions are controlled by preferential melting of clinopyroxene in the source. The basalts also have slight negative Eu-anomalies contrary to the slight positive anomalies that would be expected if clinopyroxene controlled melt compositions. Fractional crystallisation of plagioclase can reconcile these contrary indications. Nowland (2008) further concluded from Sm-Nd and Rb-Sr isotopic data that the basalts had a source composition comparable to CHUR rather than either a depleted or enriched mantle source, and are consistent with, but do not confirm, a plume-related source. Although the Johnnys Creek Formation basalts are geochemically similar to the Gairdner and Amata dolerites (Nowland 2008, Zhao et al 1994), recently determined preliminary geochronological data reported above suggests that the basalts are not co-magmatic with these dolerites.|16-MAY-23
79262|Johnnys Creek Formation|Defn author|VJ Normington, N Donnellan 5-NOV-2015
approved 9-NOV-2015
Stefan Kraus, Verity Normington|16-MAY-23
79262|Johnnys Creek Formation|Comments|The proposed type section was chosen despite the complex faulting that has occurred in the area, due to the ease of access as well as the historic significance of the site. This site has been visited by numerous geologists since the 1960s and is widely thought of as the type section of the Johnnys Creek Formation.|16-MAY-23
79262|Johnnys Creek Formation|References|Marshall TR, 2004. A review of source rocks in the Amadeus Basin: in Northern Territory Geological Survey R- (editor).
Marshall TR, Dyson IA and Liu Keyu, 2007. Petroleum systems in the Amadeus Basin, central Australia: Were they oil prone?: in Munson TJ and Ambrose GJ (editors) 'Proceedings of the Central Australian Basins Symposium, Alice Springs, 16 ¿ 18th August, 2005'. Alice Springs, Northern Territory Geological Survey, Special Publication 2, 136-146.
Munson TJ, 2014. Petroleum geology and potential of the onshore Northern Territory, 2014, Northern Territory Geological Survey, Report 22.
Normington VJ and Donnellan N, in prep. Characterisation of the Neoproterozoic stratigraphy of the northeast Amadeus Basin, Northern Territory. Record 2015-##, Northern Territory Geological Survey.
Nowland J, 2008. What caused the Rodinia breakup? Integrating basalt geochemistry and sedimentology to assess the plume model for Rodinia breakup. BSc (Hons) thesis, James Cook University.
Prichard CE and Quinlan T, 1962. The geology of the southern half of the Hermannsburg 1:250 000 sheet. BMR Report No. 61. Bureau of Mineral Resources Geology and Geophysics.
Ranford LC, Cook PJ and Wells AT, 1965. The Geology of the central part of the Amadeus Basin, Northern Territory. BMR Report No. 86. Canberra, Bureau of Mineral Resources, Geology and Geophysics.
Schopf JW, 1968. Microflora of the Bitter Springs formation, late Precambrian, central Australia. Journal of Paleontology 42, 651-688.
Serra O, 1982. Analysis of Geodip HTD Mt. Winter No. 1: in Northern Territory Geological Survey PR- (editor).
Southgate PN, 1991. A sedimentological model for the Loves Creek Member of the Bitter Springs Formation, northern Amadeus Basin: in Korsch RJ and Kennard J (editors) 'Geological and geophysical studies in the Amadeus Basin, central Australia. ' Bulletin 236. Australia, Bureau of Mineral Resources, 113-126.
Thompson J, Meffre S, Goemann K and Zhukova I, 2015. CODES, ARC Centre of Excellence in Ore Deposits, University of Tasmania, Australia, unpublished report., 4.
Wells AT, Ranford LC, Stewart AJ, Cook PJ and Shaw R, 1967. Geology of the north-eastern part of the Amadeus Basin, Northern Territory BMR Report 113, Australia.
Zhao J, McCullouch MT and Korsch RJ, 1994. Characterisation of a plume-related ~800 Ma magmatic event and its implications for basin formation in central-southern Australia. Earth and Planetary Science Letters 121, 349-367.
Zhao JX and McCullouch MT, 1993. Sm-Nd isochron ages of Late Proterozoic dyke swarms in Australia: evidence for two distinctive events of mafic magmatism and crustal extension. Chemical Geology 109, 341-354|16-MAY-23
79262|Johnnys Creek Formation|References|Ambrose GJ, 2006. Northern Territory of Australia, Onshore hydrocarbon potential 2006. Record 2006-003: in Survey NTG (editor). Darwin.
Ambrose GJ, Dunster JN, Munson TJ and Edgoose CJ, 2010. Well completion reports for NTGS stratigraphic drillholes LA05DD01 and BR05DD01, southwestern Amadeus Basin: in Northern Territory Geological Survey R- (editor).
Banks JE, 1964. Mineral reconnaissance in the Amadeus Basin, Northern Territory, for Magellan Petroleum Corporation, Northern Territory Geological Survey Open File Company Report CR 1964-015.
Edgoose C, 2013. Amadeus Basin: in Ahmad M and Munson TJ (editors) 'Geology and mineral resources of the Northern Territory; Special Publication 5', Northern Territory Government.
Glikson AY, Stewart AJ, Ballhaus CG, Clarke GL, Feeken EHJ, Leven JH, Sheraton JW and Shensu-Sun, 1996. Geology of the western Musgrave Block, central Australia with particular reference to  the mafic-ultramafic Giles Complex. Australian Geologlogical Survey Organisation Bulletin 239.
Gorter JD, 1982. Definition of the Johnny's Creek beds, Amadeus Basin. Northern Territory Geological Survey, Open File Petroleum Report PR1982-0041.
Grey K, Hill AC and Calver CR, 2011. Biostratigraphy and stratigraphic subdivision of the Cryogenian successions of Australia in a global context: in Arnaud E, Halverson GP and Shields-Zhoa G (editors) 'The geologic record of Neoproterozoic glaciations', Geological Society of London, 113-134.
Hill AC and Grey K, in prep. When non-marine becomes marine: geochemical and palaeontological evidence for marine palaeoenvironments in the upper Bitter Springs Formation and Johnnys Creek beds, Amadeus Basin, central Australia.
Hill AC, Haines PW and Grey K, 2011. Neoproterozoic glacial deposits of central Australia: in Arnaud E, Halverson GP and Shields-Zhoa G (editors) 'The geologic record of Neoproterozoic glaciations' Memoirs 36. London, Geological Society of London.
Lindsay JF, (editor) 1993. 'Geological Atlas of the Amadeus Basin.'. Canberra, Geoscience Australia.
Lindsay JF and Braiser MD, 2004. The evolution of the Precambrian atmosphere: carbon isotopic evidence from the Australian continent: in Eriksson PG, Altermann W, Nelson DR, Mueller WU and Catuneanu O (editors) ''The Precambrian Earth: tempos and events'. Developments in Precambrian Geology 12'. Amsterdam, Elsevier, 388-403.|16-MAY-23
9070|Julie Formation|Name source|Unknown, named by Wells et al (1967) and the origins of the name are not published [but  likely to be named after Julie Dam, Lat 23deg45' Long 134deg16'59.9" GDA 94].|16-MAY-23
9070|Julie Formation|Unit history|The Julie Formation was first defined by Wells et al (1967) as a member of the Pertatataka Formation. It was elevated to formation status by Preiss et al (1978) after it was recognised to have widespread distribution and as a distinctive mappable unit.|16-MAY-23
9070|Julie Formation|Geomorphic expression|The limestone and dolostone beds as well as some of the more silicified sandstone beds make prominent ridges that can be up to 200 m thick.|16-MAY-23
9070|Julie Formation|Type section locality|The proposed type section is a ridge at the back of Ross River Homestead (GDA94 53K 448438mE 7390585mN), a bushwalking track goes through the section.|16-MAY-23
9070|Julie Formation|Description at type locality|The proposed type section is described by Jenkins et al (1993). The lower 12 m of the section has an unconformable contact with the Pertatataka Formation. Here the sediments consist of dark grey, well-bedded limestone containing silt and sand-sized lithic clasts. Low-angled planar and possible swaley cross-bedding is seen. Recessive siltstone, sandstone and minor dolostone in beds up to 24 m thick overlie the limestone. The sandstone is coarse-grained and cross-bedded and the minor dolostone beds have small cauliflower chert nodules. Overlying the sandstone and minor dolostone is 80 m of alternating dolograinstone and dolostone, interbedded with minor sandstone (Figure 94a). The dolograinstone contains sand-sized grains with recrystallised ooid packages. The dolostone is fine-grained. Both lithologies contain upward-shallowing parasequences, these are well defined between 40 to 70 m. The erosional base contact of each parasequence is typically overlain by a very thin bed of very coarse-grained sandstone. This basal sandstone is then overlain by 1 to 2 m of recrystallised dolograinstone, which often contains upward-coarsening cross-bedding. Ovoid chert nodules 1 ¿ 2 cm in diameter (Figure 94b) occur at the tops of the dolograinstone units. The original oolite fabric is well-preserved within the nodules. The upper section of the parasequences consist of pale grey, fine-grained, medium- to thinly-bedded dolostone and dolomicrite. Small cauliflower chert nodules and calcite pseudomorphs after anhydrite, less than 1mm, are common within the beds of dolostone and dolomicrite. Tepee structures and poorly-preserved domical stromatolites (Figure 94c) are occasionally present within the section.|16-MAY-23
9070|Julie Formation|Extent|The Julie Formation has a widespread distribution across the basin. The formation was been recognised in the BR05DD01 drillhole in BLOODS RANGE as well as in Western Australia (Haines et al 2012). The Julie Formation is exposed throughout most of the northeast of the basin and generally forms large ridges that are typically up to 60 m high. These ridgesextend for tens of kilometres in ALICE SPRINGS, RODINGA and ILLOGWA CREEK 1:250K mapsheets.|16-MAY-23
9070|Julie Formation|General description|The formation consists mostly of carbonate rocks with sandstone beds and lenses.|16-MAY-23
9070|Julie Formation|Thickness range|The Julie Formation is about 115 m thick at the type section, with common occurrences 90 m to 180 m thick. Approximately 11 km southwest of Mount Capitor Bore the formation is up to 550 m thick. The formation thickens rapidly to this area where there is an increase in occurrence of sandstone units. The Julie Formation is approximately 120 m thick in the Ooromnna-1 well, and is absent in Mount Charlotte-1 (Wells et al 1967). The formation is approximately 38 m thick in BR05DD01 and absent in the Wallara-1 well (Haines et al 2012). .|16-MAY-23
9070|Julie Formation|Lithology|Medium to coarse-grained, dark grey, sandy dolostone is the dominant lithology of the ridges.. The thickly bedded to massive dolostone is oolitic in parts and containsspherical oolitic chert nodules. The dolostone has interbeds of oolitic and sandy pink, yellow and grey dolostone. Dark-grey and blue foetid limestone occurs near the base of the formation. Sandstone occurs as medium to coarse-grained white, kaolinitic, poorly-sorted and thickly-bedded lenses between the dolostone ridges and the underlying limestone. The upper part of the formation consists of red-brown and grey siltstone interbedded with sandy fine-grained, pink and red-brown dolostone beds. Tungussia julia stromatolites are generally poorly preserved within the dolomite beds.|16-MAY-23
9070|Julie Formation|Depositional environment|The ooid grainstone units of the Julie Formation are of shallow marine origin and represents an upward shallowing cycle which occurred after the deep marine deposition of the Pertatataka Formation (Kennard and Nicoll 1986). Jenkins et al (1993) surmised that each parasequence in the type section is likely representative of a tidal flat complex prograding over an oolite shoal.|16-MAY-23
9070|Julie Formation|Fossils|The Julie Formation contains sparse Tungussia julia stromatolites (Grey et al 2012, Walter et al 1995), these are often poorly preserved.|16-MAY-23
9070|Julie Formation|Relationships and boundaries|At the type section the Julie Formation is overlying siltstone of the Pertatataka Formation in an apparently abrupt contact. The formation is conformably overlain by the Arumbera Sandstone.|16-MAY-23
9070|Julie Formation|Identifying features|The Julie Formation is comprised of dolostone, sandstone, limestone and siltstone. Parts of the Julie Formation have the diagnostic Tungussia julia stromatolite.|16-MAY-23
9070|Julie Formation|Identifying features|The Julie Member of Wells et al. (1967) is here upgraded to formation status because of its wide distribution and usefulness as a mappable unit. It is comparable in these criteria with other formations in the Amadeus Basin.|16-MAY-23
9070|Julie Formation|Structure and Metamorphism|The Julie Formation was folded and faulted during the Petermann and Alice Springs orogenic events.|16-MAY-23
9070|Julie Formation|Age reasons|The age of the Julie Formation is constrained by the overlying Arumbera Sandstone, the lower unit has been constrained to the late Neoproterozoic (Edicaran) (Edgoose 2013)|16-MAY-23
9070|Julie Formation|Correlations|The Julie Formation has been correlated with the Rodda beds of the Officer Basin, the lower Elkera Formation, the lower Central Mount Stuart Formation and Andagera Formation of the Georgina Basin, the Marchinbar Sandstone and lower Elcho Island Formation of the Arafura Basin (Edgoose 2013, Munson et al 2013). These correlations have been made based on high delta13C isotopic values of the Julie Formation and the correlatives. Preiss et al (1978) correlated the Julie Formation with the Wonoka Formation with the Adelaide Rift Complex. The Julie Formation is also correlative to the upper Inindia beds in the southern and western Amadeus Basin (Edgoose 2013).|16-MAY-23
9070|Julie Formation|Alteration and Mineralisation|Petroleum: The Julie Formation is included in 3nd Petroleum system of Marshall et al (2007). The formation is a proven source rock in the eastern part of the basin with small gas flows detected in Dingo-2. The Julie Formation is also a potential reservoir rock (Munson 2014).|16-MAY-23
9070|Julie Formation|Geochemistry|The high delta13C isotopic values of the Julie Formation have been used to correlate the formation within Australia and globally. This isotopic excursion has been recognised in a number of exposures and drillholes across the basin (Grey et al 2012)|16-MAY-23
9070|Julie Formation|Defn author|Preiss et al (1977).|16-MAY-23
9070|Julie Formation|Defn author|VJ Normington, N Donnellan 30-SEP-2015. Approved 9-NOV-2015 Daniel Revie, Verity Normington|16-MAY-23
9070|Julie Formation|Proposed publication|BMR Journal. Preiss WV, Walter MR, Coats RP and Wells AT, 1978. Lithological correlations of Adelaidean glaciogenic rocks in parts of the Amadeus, Ngalia, and Georgina basins. BMR Journal of Australian Geology and Geophysics 3, 43-53.|16-MAY-23
9070|Julie Formation|Comments|The type section was originally proposed by Wells et al (1967) but was not officially recognised, this section is widely acknowledged as the type section for the Julie Formation.|16-MAY-23
9070|Julie Formation|References|Edgoose C, 2013. Amadeus Basin: in Ahmad M and Munson TJ (editors) 'Geology and mineral resources of the Northern Territory; Special Publication 5', Northern Territory Government. **Grey K, Allen HJ, Hill AC and Haines PW, 2012. Neoproterozoic biostratigraphy of the Amadeus Basin 'Central Australian Basins Symposium III '. Alice Springs  **Haines P, Allen H, Grey K and Edgoose C, 2012. The western Amadeus Basin: revised stratigraphy and correlations: in Ambrose GJ and Scott J (editors) 'Central Australian Basins Symposium (CABS) III: Petroleum Exploration Society of Australia. Special Publication'. **Jenkins RJ, Lindsay JF and Walter MR, 1993. Field guide to the Adelaide Geosyncline and Amadeus Basin, Australia AGSO Record 1993/35. Australian Geological Survey Organisation. **Kennard JM and Nicoll RS, 1986. Late Proterozoic and early Proterozoic depostional facies of the northern Amadeus Basin, central Australia. Sediments Down-Under. 12th International Sedimentological Congress, Canberra, Australia. 24 - 30 August 1986. Field Excursion 25B. **Marshall TR, Dyson IA and Liu Keyu, 2007. Petroleum systems in the Amadeus Basin, central Australia: Were they oil prone?: in Munson TJ and Ambrose GJ (editors) 'Proceedings of the Central Australian Basins Symposium, Alice Springs, 16 - 18th August, 2005'. Alice Springs, Northern Territory Geological Survey, Special Publication 2, 136-146. **Munson TJ, 2014. Petroleum geology and potential of the onshore Northern Territory, 2014, Northern Territory Geological Survey, Report 22. **Munson TJ, Kruse PD and Ahmad M, 2013. Centralian Superbasin: in Ahmad M and Munson TJ (editors) 'Geology and mineral resources of the Northern Territory; Special Publication 5', Northern Territory Government. **Normington VJ and Donnellan N, in prep. Characterisation of the Neoproterozoic stratigraphy of the northeast Amadeus Basin, Northern Territory. Record 2015-##, Northern Territory Geological Survey. **Preiss WV, Walter MR, Coats RP and Wells AT, 1978. Lithological correlations of Adelaidean glaciogenic rocks in parts of the Amadeus, Ngalia, and Georgina basins. BMR Journal of Australian Geology and Geophysics 3, 43-53. **Wells AT, Ranford LC, Stewart AJ, Cook PJ and Shaw R, 1967. Geology of the north-eastern part of the Amadeus Basin, Northern Territory BMR Report 113, Australia.|16-MAY-23
9070|Julie Formation|Status|1|16-MAY-23
22045|Junalki Formation|Name source|Junalkii Ridge, a prominent north-west trending linear topographic high (4km long and 500m wide)located northeast of northeres margin of Murchison Range (lat. 19deg59'30" S,  long 134deg21'40" E; GR MT330895)|16-MAY-23
22045|Junalki Formation|Unit history|Previously mapped as part of Warramunga Group of Mendum & Tonkins (1976) or Unimbra Sandstone of Blake et al. (1987)|16-MAY-23
22045|Junalki Formation|Geomorphic expression|Crops out as low hills surrounded by flat plains of recent sheet-flood sands, along northern margin of the Murchison Range.|16-MAY-23
22045|Junalki Formation|Type section locality|Type area: Immediately north of Junalki Ridge (lat. 19deg58'35" S, long 134deg21'35" E; GR MT330910). Reference area: to the southwest of Junalki Ridge ((lat. 19deg59'10" S, long 134deg20'25" E; GR MT310900)|16-MAY-23
22045|Junalki Formation|Extent|Along northern margin of the Murchison Range, from GR KMT368890 (lat 19deg59'40" S, long 134deg23'50" E) to GR KMT196886 (lat 19deg59'45" S, long 134deg13'45" E). Outcrop exposure deteriorates westward to small isoloated hills and low rises. Subsurface drilling has confirmed the continuation of Flynn Subgroup sedimentary and volcanic rocks (probably equivalent to Junalki Formation) westward onto southeastern KELLY.|16-MAY-23
22045|Junalki Formation|Thickness range|General areal extent limits Junalki Formation to a thickness not greater than1600 m.|16-MAY-23
22045|Junalki Formation|Lithology|In type area, Junalki Formation is  predominantly medium-bedded, medium-grained lithic arenite, fine- and coarse-grained tuff and possible felsic lava. The lithic arenite is  commonly  interbedded with thin-bedded siltstone and often displays festoon cross-bedding. Drilling on KELLY (lat. 19deg56'25"S, long. 133deg53'40"E; GR LT890950) has intersected rhyodacitic to rhyolitic crystal-lithic tuff, fine­ grained felsic tuff, andesitic to dacitic ignimbrite and lava (Swingler 1982). This sequence is overlain by medium-bedded and medium-grained lithic  arenite and interbedded siltstone, and represents a >200 m­ thick western extension of Junalki Formation. Drilling in southern TENNANT CREEK has intersected steeply dipping Junalki Formation lithic arenite and coarse-grained felsic tuff which are intruded by  the Palaeoproterozoic Cabbage Gum Granite (e.g., Verhoeven and Russell  1981).|16-MAY-23
22045|Junalki Formation|Depositional environment|Predominantly shallow marine.|16-MAY-23
22045|Junalki Formation|Relationships and boundaries|Conformable contact with overlying Unimbra Sandstone of the Wauchope Subgroup 10 km west of Junalki Ridge (lat. 19deg59'30" S, long 134deg15'50" E; GR MT230895). Intrusive contact with Mumbilla Granodiorite (lat. 19deg57'45" S, long 134deg21'05" E; GR MT323929). Conformable  or locally faulted contact with overlying Unimbra Sandstone. The Junalki Formation is readily identified from overlying Hatches Creek Group sedimentary rocks by its  structural attitude, interbedded fine- to coarse-grained lithic arenite, and felsic volcanic rock types and lack of ripples. 'Underlain' by penecontemporaneous epizonal granites (sensu  lato)  which are emplaced into their volcano-sedimentary counterparts.|16-MAY-23
22045|Junalki Formation|Structure and Metamorphism|Comprises east-trending upright isoclinal folds with fold wavelength dependent on relative competency   of  beds.  Siltstone-dominated  intervals are generally more tightly folded than thick-bedded sandstone intervals. The contrast in fold  intensities and localised faulting between the less competent Junalki Formation and the massive, overlying Unimbra Sandstone gives the impression of an unconformable relationship. However, cleavage orientations in interbedded andesite flows in overlying Unimbra Sandstone  (lat.   20deg01'00"S,   long.   134deg12'20"E; GR MU168870), as well as close inspection of contacts, demonstrate a similarly deformed, conformable sequence analogous to the contact between Flynn Subgroup and Tomkinson Creek Subgroup on FLYNN.|16-MAY-23
22045|Junalki Formation|Age reasons|Intruded by Mumbilla Granodiorite (1850+/-6 Ma; Compston 1991) and Cabbage Gum Granite (1848+/-7 Ma: Compston 1991). Correlated with the Brumbreu Formation which overlies the Bernborough Formation volcanic rocks (U-Pb zircon dates of 1840+/-8, and 1845+/-4 Ma  Compston, 1994).|16-MAY-23
22045|Junalki Formation|Correlations|As it is conformably overlain by the Unimbra Sandstone of the Wauchope Subgroup, the Junalki Formation represents the upper third of the entire Flynn Subgroup sequence, and is correlated with the upper sedimentary lithofacies of the Yungkulungu Formation on TENNANT CREEK and Brumbreu Formation on FLYNN. It is also probably lithostratigraphically equivalent to the Mia Mia Volcanics of the Ooradidgee Subgroup in the Davenport province.|16-MAY-23
22045|Junalki Formation|Defn author|Morrison, R.S. 1995|16-MAY-23
37707|Kakalyi Gneiss|Name source|Kakalyi Bore 23o 12' 08" S, 131o 33' 25" E, MOUNT LIEBIG.|16-MAY-23
37707|Kakalyi Gneiss|Unit history|Previously included within undifferentiated gneiss, schist, amphibolite, quartzite, granite, dolerite and pegmatite of the Arunta Complex  (Ranford 1969)|16-MAY-23
37707|Kakalyi Gneiss|Geomorphic expression|Rounded hills with bouldery outcrop|16-MAY-23
37707|Kakalyi Gneiss|Type section locality|Hill 4 km south of Kakalyi Bore at 23o 14' 11.16" S, 131o 33' 13.88" E (WGS 84), MOUNT LIEBIG.|16-MAY-23
37707|Kakalyi Gneiss|Description at type locality|Hornblende-biotite felsic migmatite with a relatively high proportion of hornblende-bearing leucosome. The leucosomes are generally swirly and random, with no overprinting fabric, and have hornblende-rich selvages.|16-MAY-23
37707|Kakalyi Gneiss|Extent|Scattered hills and outcrops in a 5 x 15 km area south of Kakalyi Bore, MOUNT LIEBIG.|16-MAY-23
37707|Kakalyi Gneiss|Lithology|Strongly migmatitic biotite-hornblende felsic orthogneiss. Leucosomes are hornblende-bearing, and in places have very hornblende- and biotite-rich selvages. The mesosome has a granodioritic composition and typically contains biotite and hornblende, with accessory titanite and ilmenite, and rare garnet. In places the migmatite grades into a weakly porphyritic biotite-hornblende granite with relatively limited migmatisation|16-MAY-23
37707|Kakalyi Gneiss|Relationships and boundaries|In faulted contact with Yaya Metamorphic Complex.|16-MAY-23
37707|Kakalyi Gneiss|Age reasons|late Palaeoproterozoic. Two samples dated. A sample from west of Yaya Creek (23o15'04"S, 131o30'17"E has a SHRIMP U-Pb zircon age for igneous cores of 1644 +/- 5 Ma with metamorphic zircon rims at 1571 +/- 5 Ma. A sample from the type locality has zircons with cores that give no clear age, and metamorphic rims at 1148 +/- 3 Ma (Kinny 2002).|16-MAY-23
37707|Kakalyi Gneiss|Correlations|Strong geochemical affinity with other granites of the Waluwiya Suite ? Larrie Granodiorite, Talyi-Talyi Charnockite, Tjungkubu Granodiorite and Russell Charnockite|16-MAY-23
37707|Kakalyi Gneiss|Comments|Migmatisation at upper amphibolite facies is attributed to the 1590-1560 Ma Chewings Orogeny and the 1150-1130 Ma Teapot Event.|16-MAY-23
37707|Kakalyi Gneiss|References|Kinny PD, 2002. SHRIMP U-Pb geochronology of Arunta Province samples from the Mount Liebig and Lake Mackay 1:250 000 mapsheets. Northern Territory Geological Survey, Technical note 2002-015. **Ranford LC, 1969. Mount Liebig, Northern Territory (First Edition). 1:250 000 geological map series explanatory notes, SF52-16. Bureau of Mineral Resources, Australia. **Scrimgeour IR, Close DF & Edgoose CJ, in prep. Mount Liebig, Northern Territory (Second Edition) 1:250 000 geological map series explanatory notes, SE 52-16. Northern Territory Geological Survey, Darwin.|16-MAY-23
80426|Kalala Member|Name source|After Kalala Station (MGA94 53K 321210mE 8209530mN; latitude -16.1881° longitude 133.3275°) in northeastern Daly Waters 1:100k mapsheet, in northeastern Daly Waters 250k mapsheet.|16-MAY-23
80426|Kalala Member|Unit history|Equivalent to informal 'Lower' Velkerri Formation of Lanigan et al (1994) and lower Velkerri Formation of subsequent usage. Part of the Velkerri Formation of the Roper Group.|16-MAY-23
80426|Kalala Member|Geomorphic expression|Not differentiated from parent Velkerri Formation in outcrop due to poor exposure. Velkerri Formation is recessive and exposures are generally restricted to rare small outcrops of buff- to white-weathering laminated siltstone and mudstone, or fragments of this lithology in skeletal soil. The formation is present in scarp slopes beneath Moroak Sandstone and also underlies extensive plains.|16-MAY-23
80426|Kalala Member|Type section locality|Kalala Member is not recognised at surface due to poor exposure, and a complete intersection of the member in drillhole Pacific Oil and Gas Ltd (POG) Alexander-1 (Barberis and Ledlie 1988) from ca 617 m depth (base) to ca 446 m (top) is therefore nominated. Velkerri Formation is 555 m thick in Alexander-1 (617-62 m depth). Alexander-1 is located at MGA94 53K 484523mE 8322964mN;latitude -15.16911° longitude 134.855921°. Core is housed in the NTGS Core Facilities in Darwin.|16-MAY-23
80426|Kalala Member|Extent|Subsurface intersections in drillholes located in Urapunga, Larrimah, Hodgson Downs,Tanumbirini and Bauhinia Downs 1:250k mapsheets, northeastern Northern Territory. Not differentiated from parent formation in outcrop due to poor exposure.|16-MAY-23
80426|Kalala Member|General description|Laminated grey-green to dark grey, variably carbonaceous claystone, with interlaminated pale grey siltstone and minor thin sandstone intervals that are glauconitic, sometimes micaceous, and increasingly common towards base. Kalala Member has a relatively higher proportion of siltstone and sandstone relative to claystone in comparison to finer-grained Amungee Member, and lacks distinctive mudrock organofacies intervals of Amungee Member. In hyperspectral data (HyLogger), the basal contact is marked by a decrease in abundance of quartz from Bessie Creek Sandstone to Kalala Member, a weathered quartzo-feldspathic mineralogy throughout Kalala Member, and a further decline in abundance of quartz at base of Amungee Member.|16-MAY-23
80426|Kalala Member|Thickness range|171 m thick. Complete intersections range from minimum of 8.5 m in BMR Urapunga-4 to maximum (composite) thickness of 305.4 m in drillhole POG Walton-2. Other significant intersections include 274 m in Santos Tanumbirini-1; 281.4 m in POG Altree-2; 250.7 m in POG Sever-1; and 207.8 m in POG Borrowdale-2.|16-MAY-23
80426|Kalala Member|Lithology|Interlaminated grey-green to dark grey, variably carbonaceous claystone and pale grey siltstone; minor, interbedded and interlaminated, fine-grained light grey sandstone that is glauconitic,sometimes micaceous, and increasingly common towards base.|16-MAY-23
80426|Kalala Member|Depositional environment|Subtidal, sub-wave base, and generally quiet marine with regular current activity, consistent with periodic turbidity currents (Munson 2016 and references therein).|16-MAY-23
80426|Kalala Member|Relationships and boundaries|Conformable and gradational lower contact with underlying Bessie Creek Sandstone. Conformable and sharp upper contact with overlying Amungee Member (see comments).|16-MAY-23
80426|Kalala Member|Identifying features|Kalala Member has a relatively high proportion of siltstone and sandstone relative to claystone, in comparison to overlying finer-grained Amungee Member, and lacks distinctive mudrock organofacies intervals of Amungee Member. See also Geophysical Expression and Geochemistry below.|16-MAY-23
80426|Kalala Member|Structure and Metamorphism|Unmetamorphosed. Flat-lying, or gentle to open folds, and/or brittle faults with minor displacements in most areas. More intense deformation (thrusts, shears, close to tight folds) in vicinity of major fault zones.|16-MAY-23
80426|Kalala Member|Age reasons|Mesoproterozoic. Maximum deposition age constrained by SHRIMP U-Pb zircon ages of 1492 +/- 4 Ma and 1493 +/- 4 Ma from rare tuffs in Showell Member of underlying Mainoru Formation (Jackson et al 1999), and by TIMS U-Pb baddeleyite age of 1312.9 +/- 0.7 Ma for Derim Derim Dolerite, which intrudes Velkerri Formation (Collins et al 2018). Organic-rich shales from overlying Amungee Member have been dated by Re-Os method at 1417 +/- 29 Ma (A organofacies) and 1361 +/- 21 Ma (C organofacies; Creaser and Kendall 2007, Kendall et al 2009).|16-MAY-23
80426|Kalala Member|Correlations|No known correlatives at member level. Parent Velkerri Formation is probably equivalent to Lake Woods beds of Renner Group of Tomkinson Province (Hussey et al 2001), Tijunna Group (in part) of Birrindudu Basin; and Mullera Formation (in part) of South Nicholson Basin (Munson 2016).|16-MAY-23
80426|Kalala Member|Alteration and Mineralisation|Some in situ weathering of minerals, including alteration of labile minerals to clays.|16-MAY-23
80426|Kalala Member|Geophysical Expression|Gamma logs show a marked upward upward-step in values at basal contact with Bessie Creek Sandstone; the gamma trace typically shows an overall, gentle decline up-section to another upward step in values at base of Amungee Member. Resistivity logs step downwards at contact with Bessie Creek Sandstone, have a low flat character throughout Kalala Member, then step upwards at base of Amungee Member.|16-MAY-23
80426|Kalala Member|Geochemistry|TOC of mudrocks is generally lean; organic-rich mudrock intervals are absent. Phosphate, carbonate, and redox-sensitive trace elements (eg, U, Ni, V, Mo, Zn, Cu, Tl) all have typically low values, slightly higher towards the base, in comparison to overlying Amungee Member. Log values for some oxides and heavy mineral trace elements (eg, Al2O3, K2O, Sc, Nb, Th, Sn, Cr) are elevated relative to Amungee Member.|16-MAY-23
80426|Kalala Member|Defn author|TJ Munson, D Revie, April 2018.|16-MAY-23
80426|Kalala Member|Proposed publication|Munson TJ and Revie D, 2018. Stratigraphic subdivision of Velkerri Formation, Roper Group, McArthur Basin, Northern Territory. Northern Territory Geological Survey, Record 2018-006.|16-MAY-23
80426|Kalala Member|Comments|Upper contact with Amungee Member often marked by thin calcite bed (Hoffman 2015).  A few rare, poorly preserved palynomorphs have been recovered from Kalala Member in drillhole POG Altree-2 (Grey (2015).|16-MAY-23
80426|Kalala Member|References|Barberis C and Ledlie I, 1988. Alexander No 1, EP 4, McArthur Basin, NT. Well completion report. Pacific Oil & Gas Ltd. Northern Territory Geological Survey, Open File Petroleum Report PR1989-0007. **Collins A, Farkas J, Glorie S, Cox G, Blades ML, Yang Bo, Nixon A, Bullen M, Foden JD, Dosseto A, Payne JL, Denyszyn S, Edgoose CJ, Close D, Munson TJ, Menpes S, Spagnuolo S, Gusterhuber J, Sheridan M, Baruch-Jurado E and Close D, 2018. Orogens to oil: government-industry-academia collaboration to better understand the greater McArthur Basin: in Annual Geoscience Exploration Seminar (AGES) Proceedings, Alice Springs, Northern Territory, 20-21 March 2018. Northern Territory Geological Survey, Darwin. 49-51. **Creaser RA and Kendall B, 2007. Re-Os geochronology of organic-rich shales; Placing absolute time pins in ancient sedimentary basins. American Geophysical Union, Fall Meeting 2007, abstract #V31G-01. ** Grey K, 2015. Mesoproterozoic biostratigraphic correlation in the Beetaloo Sub-basin, Northern Territory, Australia and potential for correlation with other northern Australian basins: in 'Annual Geoscience Exploration Seminar (AGES) 2015. Record of Abstracts.' Northern Territory Geological Survey, Record 2015-002. **Hoffman TW, 2015. Recent drilling results provide new insights into the western Palaeoproterozoic to Mesoproterozoic McArthur Basin: in 'Annual Geoscience Exploration Seminar (AGES) 2015. Record of Abstracts.' Northern Territory Geological Survey, Record 2015-002, 50-55. **Jackson MJ, Sweet IP, Page RW and Bradshaw BE, 1999. The South Nicholson and Roper Groups: Evidence for the early Mesoproterozoic Roper Superbasin: in Bradshaw BE and Scott DL (editors). 'Integrated basin analysis of the Isa Superbasin using seismic, well-log and geopotential data: an evaluation of the economic potential of the northern Lawn Hill Platform.' Australian Geological Survey Organisation Record 1999/19 (CD ROM), 36-45. **Kendall B, Creaser RA, Gordon GW and Anbar AD, 2009. Re¿Os and Mo isotope systematics of black shales from the Middle Proterozoic Velkerri and Wollogorang Formations, McArthur Basin, northern Australia. Geochimica et Cosmochimica Acta 73, 2534-2558. **Lanigan K, Hibbird S, Menpes S and Torkington J, 1994. Petroleum exploration in the Proterozoic Beetaloo Sub basin, Northern Territory. APEA Journal 34, 674-691. **Munson TJ, 2016. Sedimentary characterisation of the Wilton package, greater McArthur Basin, Northern Territory. Northern Territory Geological Survey, Record 2016-003.|16-MAY-23
79093|Kanandra Metamorphics|Name source|Kanandra Dam in eastern ALCOOTA 1:250 000 mapsheet, Northern Territory (498286mE 7482306mN, GDA94, Zone53).|16-MAY-23
79093|Kanandra Metamorphics|Unit history|Previously 'Kanandra Granulite' of Shaw et al (1975), Steward et al (1980) and Freeman (1986), which included felsic gneiss, mafic granulite, migmatitic paragneiss, and calc-silicate rocks.|16-MAY-23
79093|Kanandra Metamorphics|Geomorphic expression|Moderately weathered, isolated rises, peaks and low hills. Locally fresh boulders, blocks and pavements.|16-MAY-23
79093|Kanandra Metamorphics|Type section locality|No single outcrop contains all informal subunits and their variations. Access to the outcrops are via public roads and private tracks. Some off-track driving/walking might be required. A type locality containing the most voluminous subunit of the Kanandra Metamorphics is at 135.1341degreesE 22.7503degreesS (GDA 2020) near Black Point in southwestern HUCKITTA 1:250 000 mapsheet (Weisheit et al in prep). Rocks at this location are a granulitic to migmatitic paragneiss with sillimanite and poikilitic garnet interlayered with Carmencita Metadolerite. A reference locality with calc-silicate rocks at 135.5937degreesE 22.7408degreesS (GDA 2020) south of the eastern Mopunga Range in central HUCKITTA comprises weakly deformed epidote-calcite-garnet-diopside calc-silicate rock interlayered at the metre-scale with biotite-rich biotite-quartz-feldspar paragneiss-schist. A reference locality with calc-silicate rocks at 134.8922degreesE 22.7379degreesS (GDA 2020) close to Mount Swan in ALCOOTA (Beyer et al in prep) comprises a fine-grained equigranular quartz-plagioclase-green diopside-titanite+/-garnet+/-orthopyroxene calc-silicate rock interlayered with Carmencita Metadolerite.|16-MAY-23
79093|Kanandra Metamorphics|Description at type locality|Metamudstone, metagreywacke, and metasandstone gneisses, rare calc-silicate rocks. Granulite to amphibolite facies, commonly migmatitic. Locally retrogressed to amphibolite- and greenschist-facies rocks. Moderately to strongly gneissic, locally mylonitic. Informal members include paragneisses and calc-silicate rocks.|16-MAY-23
79093|Kanandra Metamorphics|Extent|The unit outcrops in the Kanandra Domain south of and within the Delny Shear Zone in central and western HUCKITTA and southwestern ALCOOTA around Mount Swan (~575000mE-484000mE and 7481000mN-7498000mN).|16-MAY-23
79093|Kanandra Metamorphics|General description|Constituent units include granulite- to amphibolite-facies paragneisses and rare calc-silicate rocks. The metamorphic grade is highest distal to bounding Delny and Entire Point shear zones. Within those shear zones, the rocks are overprinted by amphibolite-grade mylonites and ultra-mylonites and rare greenschist facies mylonites. Intruded by and commonly associated with mafic granulite of the Carmencita Metadolerite and felsic igneous rocks of the Alkara Suite.|16-MAY-23
79093|Kanandra Metamorphics|Thickness range|Thickness not measured. The thickness of original sedimentary units, or their stratigraphic order and an absolute younging direction is difficult to determine because of structural and metamorphic overprint.|16-MAY-23
79093|Kanandra Metamorphics|Lithology|Metamudstone, metagreywacke, and metasandstone gneisses, rare calc-silicate rocks. Granulite to amphibolite facies, commonly migmatitic. Locally retrogressed to amphibolite- and greenschist-facies rocks. Moderately to strongly gneissic, locally mylonitic. Unnamed members include garnet-biotite-sillimanite-plagioclase-K-feldspar-quartz+/-cordierite-ilmenite+/-spinel+/-magnetite paragneiss with extensive leucocratic layering that may transition into bodies of Jamaica and Canefire granites; epidote-calcite-garnet+/-diopside+/-titanite calc-silicate rocks; and plagioclase-amphibole para-amphibolite with mm- to cm-scale layering.|16-MAY-23
79093|Kanandra Metamorphics|Depositional environment|Difficult to determine due to intense metamorphic and structural overprint. Based on geochemical characteristics of the intruding Carmencita Metadolerite, it is possible that the Kanandra Metamorphics was deposited in a nascent continental rift setting.|16-MAY-23
79093|Kanandra Metamorphics|Relationships and boundaries|The oldest preserved rocks south of the Delny Shear Zone in HUCKITTA. Intruded by Carmencita Metadolerite and rocks of the [Alkara] Suite.|16-MAY-23
79093|Kanandra Metamorphics|Identifying features|Commonly maroon garnet-bearing, granulite-facies metasedimentary rocks. They are the only metasedimentary rocks in the Kanandra Domain in southwestern HUCKITTA and eastern ALCOOTA (Shaw et al 1975, Beyer et al in prep). Distinguished from the nearby Yambla Gneiss by the maroon-colour and dull texture of garnet and presence of migmatite structures in the Kanandra Metamorphics compared to the glassy fuchsia-coloured garnet and lack of migmatite structures in the nearby Yambla Gneiss.|16-MAY-23
79093|Kanandra Metamorphics|Structure and Metamorphism|Granoblastic to gneissic or mylonitic, commonly migmatitic. Irregularly layered, isoclinally folded at cm-scale. Granulite to amphibolite facies, locally retrogressed.|16-MAY-23
79093|Kanandra Metamorphics|Age reasons|Deposited between the youngest maximum depositional age of ca 1.80 Ga and the earliest metamorphism at ca 1.78 Ga. The metamudstone component has reported 207Pb/206Pb zircon maximum depositional ages of 1844 +/- 8 Ma (Smith 2001), 1818 +/- 6 Ma (Kositcin et al 2018), 1804 +/- 10 Ma (Bodorkos et al 2013), and 1797 +/- 11 Ma (Reno et al 2018).|16-MAY-23
79093|Kanandra Metamorphics|Correlations|Interpreted to be age-equivalent to Bonya, Deep Bore, and Perenti metamorphics of the northeastern Aileron Province.|16-MAY-23
79093|Kanandra Metamorphics|Alteration and Mineralisation|Weakly to moderately, locally deeply weathered at surface. Silicification is common close to regional faults and shear zones. No known mineralisation.|16-MAY-23
79093|Kanandra Metamorphics|Geophysical Expression|Commonly associated with magnetic low zones and trends; no characteristic gravity or radiometric response.|16-MAY-23
79093|Kanandra Metamorphics|Defn author|Anett Weisheit, Barry Reno, Eloise Beyer, Pablo Farias (NT Department of Industry, Tourism and Trade, Northern Territory Geological Survey) 3-MAY-2022.|16-MAY-23
79093|Kanandra Metamorphics|References|Beyer E et al, 2022. Alcoota, Northern Territory (Second Edition). 1:250 000 geological map series explanatory notes, SF53-11. Northern Territory Geological Survey, Darwin.  **Bodorkos S, Beyer EE, Edgoose CJ, Whelan JA, Webb G, Vandenberg LC and Hallett L, 2013. Summary of results. Joint NTGS-GA geochronology project: Central and eastern Arunta Region, January 2008-June 2011. Northern Territory Geological Survey, Record 2013-003.  **Freeman MJ, Black LA, Offe LA, Senior BR, Shaw RD, Shergold JH, Simpson CJ, Walter MR, Warren RG, Donnellan N, Horsfall CJ, Laurie JR and Walley AM, 1986. Huckitta, Northern Territory (Second Edition). 1:250 000 geological map series, SF 53-11. Northern Territory Geological Survey, Darwin.  **Kositcin N, Reno BL and Beyer EE, 2018. Summary of results. Joint NTGS-GA geochronology project: Aileron Province, July 2015-June 2016. Northern Territory Geological Survey, Record 2018-005.  **Reno BL, Beyer EE, Thompson JM and Meffre S, 2018. NTGS laser ablation ICP?MS zircon petrochronology project: Aileron Province, Jinka and Dneiper 1:100 000 mapsheets. Northern Territory Geological Survey, Record 2018-003.  **Shaw RD and Stewart AJ, 1975. Towards a stratigraphy of the Arunta Block. Geological Society of Australia, 1st Australian Geological Convention, Abstracts, 35.  **Smith J 2001. Summary of results. Joint NTGS-AGSO age determination program. Northern Territory Geological Survey, Record 2001-007.  **Stewart AJ, Shaw RD, Offe LA, Langworthy AP, Warren RG, Allen AR and Clark DB, 1980. Stratigraphic definitions of named units in the Arunta Block, Northern Territory. Bureau of Mineral Resources, Australia, Report 221.  **Weisheit A et al, in prep. Huckitta, Northern Territory (Third Edition). 1:250 000 geological map series explanatory notes, SF53-11. Northern Territory Geological Survey, Darwin.|16-MAY-23
35316|Karukali Quartzite|Name source|Karukali Outstation at location 24o 54' 15.57" S, 129o 21' 09.06" E (WGS 84).|16-MAY-23
35316|Karukali Quartzite|Unit history|Previously described as the basal unit of the Mount Harris Basalt (Forman 1966).|16-MAY-23
35316|Karukali Quartzite|Constituents|Nil|16-MAY-23
35316|Karukali Quartzite|Geomorphic expression|Comprises scarps and dip slopes of isolated low hills.|16-MAY-23
35316|Karukali Quartzite|Type section locality|17 km southeast of Walu Outstation at location 24o 49' 58.95" S, 129o36' 45.31" E (WGS 84). Lower contact is quartz gravel beds and quartz pebble conglomerate above coarsely porphyritic biotite granite. Upper contact is obscured by ~0.5m of scree material, however the stratigraphic sequence is equigranular, silicified quartzite overlain by epidotised, silicified metabasalt. Thickness of section is ~10 m.|16-MAY-23
35316|Karukali Quartzite|Extent|Scattered outcrops in the central west section of the Bloods Range 1:100 000 map sheet area in areas approximately 5 km northeast and 13-17 km southeast of Walu Outstation.|16-MAY-23
35316|Karukali Quartzite|Thickness range|5-10 metres.|16-MAY-23
35316|Karukali Quartzite|Lithology|Quartzite and quartz-muscovite schist, often rich in hematite and magnetite, minor quartz pebble conglomerate.|16-MAY-23
35316|Karukali Quartzite|Depositional environment|Shallow marine.|16-MAY-23
35316|Karukali Quartzite|Relationships and boundaries|Unconformably overlies undivided Pottoyu Granite Suite of the Musgrave Block and is overlain by basal units of the Tjauwata Group in a probable disconformable relationship, although stratigraphic contact is not well exposed. The Karukali Quartzite is crosscut by mafic dykes probably associated with the Alcurra Dyke Swarm (~1078 Ma).|16-MAY-23
35316|Karukali Quartzite|Age reasons|Mesoproterozoic. Unconformably overlies the 1190-1140 Ma undivided Pottoyu Granite Suite and is intruded by mafic dykes interpreted to belong to the ~1078 Ma Alcurra Dyke Swarm.|16-MAY-23
35316|Karukali Quartzite|Correlations|Probably a distal equivalent to the MacDougall Formation, basal Tollu Group, (Daniels 1974) that outcrops in the MacDougall Bluff Region in Western Australia.|16-MAY-23
35316|Karukali Quartzite|Proposed publication|Close, D.F., Edgoose, C.J., Scrimgeour, I.R., 2002. Bloods Range and Hull 1:100 000 geological special, Northern Territory Geological Survey, Explanatory notes.|16-MAY-23
35316|Karukali Quartzite|References|98/29502 - Forman, D.J., 1966. Bloods Range Northern Territory 1:250 000 geological series explanatory notes. Sheet (SG53-3). Bureau of Mineral Resources, Australia. **79/01069 - Daniels J.L., 1974, The geology of the Blackstone region, Western Australia. Geological Survey of Western Australia. Bulletin, 123.|16-MAY-23
75947|Keri Metamorphics|Name source|After Keri homestead GDA 94 52L 669230mE 8534660mN (13°15'9"S 130°33'43"E) on Pine Creek 1:250 000 mapsheet, Reynolds River 1:100 000 mapsheet, Litchfield Province, Pine Creek Orogen, Northern Territory.|16-MAY-23
75947|Keri Metamorphics|Unit history|Previously known as Wangi Basics, first used by Needham and Stuart-Smith (1984) and formally defined in Dundas et al (1987). The name Wangi Basics is abandoned, as it is now known to comprise distinct geochemical groups which are genetically unrelated.|16-MAY-23
75947|Keri Metamorphics|Geomorphic expression|Boulder-strewn outcrops and well rounded boulders|16-MAY-23
75947|Keri Metamorphics|Type section locality|Low boulder-strewn hills 12 km north of Keri homestead on REYNOLDS RIVER (GDA 94 52L 670455mE 8548345mN; 13°7'35"S 130°34'21"E).|16-MAY-23
75947|Keri Metamorphics|Description at type locality|Low boulder-strewn hills among Cenozoic cover.|16-MAY-23
75947|Keri Metamorphics|Extent|Exposures occur within an area of 16 km2 in NW Reynolds River 1:100 000 mapsheet; however, magnetic imagery indicates that true extent under surficial cover may be much greater.|16-MAY-23
75947|Keri Metamorphics|General description|Metamorphosed noritic cumulates, metapyroxenite and metaperidotite, and garnet-bearing mafic amphibolite (Glass 2007, 2010). Only exposed in NW Reynolds River 1:100 000 mapsheet.|16-MAY-23
75947|Keri Metamorphics|Thickness range|Not known due to poor exposure|16-MAY-23
75947|Keri Metamorphics|Lithology|Metamorphosed mafic/ultramafic assemblages (metamorphosed noritic cumulate, metapyroxenite and metaperidotite) and garnet-bearing mafic amphibolite (metaferrogabbro) (Glass 2007, 2010).|16-MAY-23
75947|Keri Metamorphics|Relationships and boundaries|Contact relationships not observed, but possibly intrudes Welltree Metamorphics (Pietsch 1989).|16-MAY-23
75947|Keri Metamorphics|Identifying features|Metamorphosed mafic/ultramafic assemblages are moderate to strongly foliated (typical mineral assemblages include tremolite, anthophyllite, actinolite and hornblende). Metaferrogabbro has distinctive large garnet porphyroblasts up to and greater than 10 mm in diameter, which commonly amalgamate to form linear segregations in an amphibole-rich groundmass.|16-MAY-23
75947|Keri Metamorphics|Structure and Metamorphism|Amphibolite-facies metamorphism|16-MAY-23
75947|Keri Metamorphics|Age reasons|Carson et al (2009) determined a weighted mean 207Pb/206Pb SHRIMP date of 1860 +/- 6 Ma (95% confidence level) for a garnet-bearing mafic amphibolite, which is interpreted to represent the magmatic crystallisation age for this sample.|16-MAY-23
75947|Keri Metamorphics|Correlations|None known.|16-MAY-23
75947|Keri Metamorphics|Alteration and Mineralisation|Abundant fibrous amphibole (tremolite-actinolite) is interlaminated with chlorite and is most likely replacement product of primary orthopyroxene. Uralitic amphibole is most likely derived from granular clinopyroxene. Residual partly seriticised (+/- clinozoisite) platy plagioclase (up to 2 mm in size) has in part been overprinted by recrystallised amphibole. No known mineralisation.|16-MAY-23
75947|Keri Metamorphics|Geophysical Expression|Appears to be associated with a magnetic high in northwestern corner of Reynolds River 1:100 000 mapsheet, which extends slightly into adjoining mapsheets. No observable radiometric or gravity response.|16-MAY-23
75947|Keri Metamorphics|Geochemistry|Metamorphosed noritic cumulate is typically low Ti and highly magnesian. Metaferrogabbro is metamorphosed plagioclase-pyroxene cumulate with very high FeO (18.8-23.2 wt%; Glass 2010).|16-MAY-23
75947|Keri Metamorphics|References|CARSON CJ, Claoué-Long J, Stern RA, Close DF, Scrimgeour IR and Glass, LM, 2009. Summary of results. Joint NTGS-GA geochronology project: Arunta and Pine Creek regions, July 2006-May 2007. Northern Territory Geological Survey Record 2009-1.  **DUNDAS DL, Edgoose CJ, Fahey GM and Fahey JE, 1987. Daly River 1:100 000 Geological Map Series. Northern Territory Geological Survey Explanatory Notes (5070).  **GLASS LM, 2007. Geochemistry of mafic rocks in the Litchfield Province, western Pine Creek Orogen: Evidence for a Palaeoproterozoic arc-related setting and links to the Halls Creek Orogen: in 'Annual Geoscience Exploration Seminar (AGES) 2007. Record of Abstracts.' Northern Territory Geological Survey, Record 2007 001.  **GLASS LM, 2010. Palaeoproterozoic island-arc-related rocks of the Litchfield Province, western Pine Creek Orogen, Northern Territory. Northern Territory Geological Survey, Record 2010-005.  **NEEDHAM RS, Stuart-Smith PG, 1984. Geology of the Pine Creek Geosyncline, Northern Territory, 1:500 000 scale map. Bureau of Mineral Resources, Australian Bureau of Mineral Resources, Canberra. ACT.   **PIETSCH BA, 1989. Reynolds River, 1:100 000 Geological Map Series. Northern Territory Geological Survey Explanatory Notes (5071).|16-MAY-23
83007|Kerringnew Formation|Name source|Kerringnew Formation is named after Kerringnew Swamp (GDA94, 53K, 651941mE, 7828708mN), approx. 20 km southeast of type intersection.|16-MAY-23
83007|Kerringnew Formation|Geomorphic expression|No known outcrops.|16-MAY-23
83007|Kerringnew Formation|Type section locality|Drill hole NDIBK04, down-hole depth from 165 to 236 m. Drillhole location 635380mE 7839553mN (MGA94 zone 53) / 	19.534200S 136.290361E. Drill core is stored at the NTGS core library in Alice Springs.|16-MAY-23
83007|Kerringnew Formation|Description at type locality|Upper interval of folded and steeply-dipping, green-grey and red, metamorphosed, interbedded iron-rich and siliceous sedimentary rocks, with some possible volcanic (tuffaceous?) layers. Garnet and amphibole are prominent metamorphic minerals in hand specimen and thin-section throughout this interval. Beds of hematite and magnetite occur locally. Lower interval of red to light grey and dark green marble and skarn. The boundary between these two intervals is marked by a sharp change from massive marble to well-bedded sedimentary rock at 188 m down-hole depth.|16-MAY-23
83007|Kerringnew Formation|Extent|Unknown. Other drillholes in the region intersect rocks that are younger than this unit, so its true extent is unconstrained. Undated lithologies in other drillholes in the region, which are currently included in the Alroy Formation (e.g. DD80 AL3, DDH005), might be equivalent to this unit, which would demonstrate a more widespread extent.|16-MAY-23
83007|Kerringnew Formation|General description|Only known in type interval. See description above.|16-MAY-23
83007|Kerringnew Formation|Thickness range|71 m, apparent thickness only, in type section. Unconstrained due to insufficient data.|16-MAY-23
83007|Kerringnew Formation|Lithology|Interbedded iron-rich and siliceous sedimentary rocks, with minor volcanic layers, and marble.|16-MAY-23
83007|Kerringnew Formation|Relationships and boundaries|Sharp nonconformity between this unit and overlying Kalkarindji Suite. Relationship between this unit and underlying Confusion Dam Formation is difficult to determine due to the massive nature of the marble interval, as well as deformation and metamorphism (see Structure and metamorphism below).|16-MAY-23
83007|Kerringnew Formation|Identifying features|Lithologically comparable to parts of the Alroy Formation. However, the interpreted depositional age of 1894.2 +/- 3.4 Ma (see Age & evidence) is significantly older than the interpreted maximum depositional age of 1872.5+/- 3 Ma for the Alroy Formation (Kositcin et al., in prep), and distinguishes the Kerringnew Formation as a separate older unit.|16-MAY-23
83007|Kerringnew Formation|Structure and Metamorphism|Unit is steeply-dipping, folded and metamorphosed. Folds are open to tight and relatively uncommon in drill core. Amphibolite-facies metamorphic assemblages containing garnet, biotite and amphibole are common in the upper interval. Bedding is well-preserved in many locations, although much of the marble interval is massive. Brittle structures, including veins, faults and breccia, are well-developed locally, especially in the more carbonate-rich lithologies.|16-MAY-23
83007|Kerringnew Formation|Age reasons|A depositional age of 1894.2 +/- 3.4 Ma has been interpreted for the Kerringnew Formation, based on the chemistry, unimodal zircon age population and euhedral zircon morphology of a sample of interpreted tuffaceous sediment from this unit (Kositcin, Cross et al., in prep).|16-MAY-23
83007|Kerringnew Formation|Correlations|None known.|16-MAY-23
83007|Kerringnew Formation|Alteration and Mineralisation|Carbonate interval contains minor Zn mineralisation.|16-MAY-23
83007|Kerringnew Formation|Geophysical Expression|Upper interval, which is characterised by elevated Fe-content, has down-hole measured density values of around 3.2 g/cc, which may be contributing to a subtle, localised high in regional gravity imagery. Given the elevated Fe content, there is the potential for this unit to contain significant magnetite, which would result in elevated magnetic susceptibility.|16-MAY-23
83007|Kerringnew Formation|Defn author|A.D. Clark 24-MAR-2022.|16-MAY-23
83007|Kerringnew Formation|Proposed publication|Schofield and Clark et al., (in prep). Geology of the East Tennant area, Northern Territory, journal publication.|16-MAY-23
83007|Kerringnew Formation|References|Kositcin, N., Cross A.J., et al., in prep. Geochronology of the East Tennant area, Geoscience Australia record.|16-MAY-23
69563|Kiana Group|Name source|From Kiana property in northeastern WALLHALLOW-northwestern CALVERT HILLS.|16-MAY-23
69563|Kiana Group|Unit history|Robinson Beds (Noakes 1956).|16-MAY-23
69563|Kiana Group|Constituents|Bukalara Sandstone, Cox Formation (Dunn 1963).|16-MAY-23
69563|Kiana Group|Geomorphic expression|Strongly jointed plateaux (Bukalara Sandstone), low hills and rubbly rises (Cox Formation).|16-MAY-23
69563|Kiana Group|Type section locality|Type sections of constituent named units. Bukalara Sandstone: boundary stratotypes at 15o50.5'S, 135o12.9'E (base) and 15o49.0'S, 135o8.6'E (top) in southeastern MOUNT YOUNG (Kruse in Pietsch et al 1992); Cox Formation: type locality surrounding 15o55'S, 135o01'E in southeastern MOUNT YOUNG (Haines et al 1993).|16-MAY-23
69563|Kiana Group|Extent|Along northern margin of Georgina and Dunmarra Basins in MOUNT DRUMMOND, CALVERT HILLS, ROBINSON RIVER, WALLHALLOW, BAUHINIA DOWNS, MOUNT YOUNG, TANUMBIRINI and HODGSON DOWNS.|16-MAY-23
69563|Kiana Group|Thickness range|Maximum 300 m in Abner Range (BAUHINIA DOWNS; Smith 1964).|16-MAY-23
69563|Kiana Group|Lithology|Thin- to thick-bedded, very fine to very coarse quartz sandstone, commonly feldspathic, some micaceous; interbedded micaceous siltstone and shale; minor shale and conglomerate.|16-MAY-23
69563|Kiana Group|Depositional environment|High-energy braided fluviatile, shallow (including storm-influenced) marine.|16-MAY-23
69563|Kiana Group|Relationships and boundaries|Unconformably overlies various units of McArthur Basin, Murphy Inlier and South Nicholson Basin, youngest being topmost units of Mesoproterozoic Roper Group (McArthur Basin) and South Nicholson Group (South Nicholson Basin). Unconformably overlain by early Cambrian Kalkarindji Volcanic Group or where this is absent, Top Springs Limestone of Barkly Group (Kruse et al in prep) or where these are absent, Cretaceous sandstone.|16-MAY-23
69563|Kiana Group|Age reasons|Age stratigraphically constrained to Ectasian to earliest Cambrian. Carbonaceous macrofossil Chuaria in coeval Raiwalla Shale of Wessel Group, Arafura Basin (Haines 1998) favours a Neoproterozoic age (Rawlings et al 1997). Absence of glacial deposits in Wessel Group, in conjunction with its undisturbed, flat-lying attitude and stratigraphic position immediately below fossiliferous Middle Cambrian rocks, suggests a post-glacial Neoproterozoic (Ediacaran) age for it and coeval Kiana Group.|16-MAY-23
69563|Kiana Group|Correlations|Buckingham Bay Sandstone and Raiwalla Shale of Wessel Group (Arafura Basin).|16-MAY-23
69563|Kiana Group|Defn author|Kruse, P.D., Rawlings, D.J. , Aug-2005|16-MAY-23
69563|Kiana Group|Comments|This group unites all putatively Neoproterozoic rocks along northern margin of Georgina and Dunmarra Basins.|16-MAY-23
69563|Kiana Group|References|**DUNN PR, 1963. Hodgson Downs, Northern Territory (First Edition). 1:250 000 geological map series explanatory notes, SD 53-14. Bureau of Mineral Resources, Australia, Canberra.  **HAINES PW, 1998. Chuaria Walcott, 1899 in the lower Wessel Group, Arafura Basin, northern Australia. Alcheringa 22, 1-8.  **HAINES PW, Pietsch BA, Rawlings DJ and Madigan TL, 1993. Mount Young, Northern Territory (Second Edition). 1:250 000 geological map series explanatory notes, SE 53-15. Northern Territory Geological Survey, Darwin.  **KRUSE PD, Radke BM and Duffett ML, in prep. Ranken-Avon Downs, Northern Territory (Second Edition). 1:250 000 geological map series explanatory notes, SE 53-16, SF 53-04. Northern Territory Geological Survey, Darwin.  **NOAKES LC, 1956. Upper Proterozoic and sub-Cambrian rocks in Australia. XX International Geological Congress, Mexico 2, 213-238 [Reprinted 1957 Bureau of Mineral Resources, Australia, Bulletin 49, 213-238].  **PIETSCH BA, Rawlings DJ, Creaser PM, Kruse PD, Ahmad M, Ferenczi PA and Findhammer TLR, 1991 [1992]. Bauhinia Downs, Northern Territory (Second Edition). 1:250 000 geological map series explanatory notes, SE 53-3. Northern Territory Geological Survey, Darwin.  **RAWLINGS DJ, Haines PW, Madigan TLA, Pietsch BA, Sweet IP, Plumb KA and Krassay AA, 1997. Arnhem Bay-Gove, Northern Territory (Second Edition). 1:250 000 geological map series explanatory notes, SD 53-3,4. Northern Territory Geological Survey, Darwin and Australian Geological Survey Organisation, Canberra.  **SMITH JW, 1964. Bauhinia Downs, Northern Territory (First Edition). 1:250 000 geological map series explanatory notes, SE 53-3. Bureau of Mineral Resources, Australia, Canberra.|16-MAY-23
78971|King Member|Name source|Easily accessible outcrops occur in King River from old Victoria Highway crossing at 14.701°S, 132.070°E (MGA94 Zone 52: 830641mE 8372495mN) downstream to confluence with Katherine River at 14.695°S, 131.980°E (MGA94 Zone 52: 821083mE 8373446mN).|16-MAY-23
78971|King Member|Unit history|None.|16-MAY-23
78971|King Member|Geomorphic expression|Restricted exposure due to widespread cover of Cretaceous rocks. Exposures form low hills with karst features, including pavements, caves, dolines, karren and kamenitza.|16-MAY-23
78971|King Member|Type section locality|51.5-109.8 m in cored drillhole NTGS 86/1, drilled at 14°09'50"S, 131°23'50"E (MGA94 Zone 52: 758890mE 8432980mN). Core stored at Northern Territory Geological Survey Core Library, Darwin.|16-MAY-23
78971|King Member|Description at type locality|Dark red-pink to pale pink, medium to coarse crystalline dolostone, lightening in colour with depth. Minor intervals of microbial and stromatolitic dolostone, and sparse thin shale.|16-MAY-23
78971|King Member|Extent|Area bounded by latitudes 13.929°S and 14.814°S and longitudes 131.244°E and 132.169°E  in central Daly Basin, extending a length of some 138 km northwest to southeast, with width about 33 km. Daly River transects this area.|16-MAY-23
78971|King Member|Thickness range|58.3 m in type section in drillhole NTGS86/1; 93 km to southeast in drillhole KRVH1 (MGA94 Zone 52: 830499mE 8372804mN), it reaches maximum recorded thickness of 101.7 m.|16-MAY-23
78971|King Member|Depositional environment|Shallow marine, remote from sources of siliciclastic sediment.|16-MAY-23
78971|King Member|Fossils|None recorded.|16-MAY-23
78971|King Member|Diastems or hiatuses|Numerous erosive surfaces present, but probably only of local extent. Highly cavernous, particularly in upper sections, probably resulting from subaerial exposure prior to deposition of overlying Florina Formation and at various periods since.|16-MAY-23
78971|King Member|Relationships and boundaries|Conformably overlies Briggs Member of Oolloo Dolostone. Boundary in type section marked by stromatolites overlying eroded surface on ooid dolograinstone. Erosive surface considered to be a local feature probably not representing major time break. Rocks above contact are generally massive, whereas those below are well bedded. Contact not exposed. Unconformably overlain by Florina Formation; bedding in both formations essentially parallel, but strongly karstified contact (not exposed) indicates considerable time break. Where Florina Formation not present, unconformably overlain by Cretaceous siliciclastic rocks; contact not exposed. In type section, upper third of member has been removed by erosion prior to deposition of overlying Cretaceous sediments.|16-MAY-23
78971|King Member|Identifying features|Characterised by pink-red colour, coarsely crystalline dolomitic textures, general lack of well-defined bedding that results in massive appearance, and widespread development of solution cavities. Underlying Briggs Member is distinguished by its finely crystalline dolomitic textures, well defined bedding and common occurrence of ooids. Overlying Florina Formation is distinguished by its fine-grained, well bedded, grey dolostone and intervals of fine-grained glauconitic siliciclastic rocks.|16-MAY-23
78971|King Member|Structure and Metamorphism|Flat lying to gently dipping towards centre of basin. Unmetamorphosed.|16-MAY-23
78971|King Member|Age reasons|Unfossiliferous but age broadly constrained by early middle Cambrian Tindall Limestone below and Early Ordovician Florina Formation above. Middle Cambrian age is considered most likely from presence of generally conformable contacts between units of Daly River Group, the lower part of which is securely dated as middle Cambrian, and from broad lithological correlations with Georgina Basin middle Cambrian succession.|16-MAY-23
78971|King Member|Correlations|Camooweal Dolostone of central Georgina Basin, based on lithological correlation of underlying Jinduckin Formation with Wonarah Formation of that region.|16-MAY-23
78971|King Member|Alteration and Mineralisation|Dolomitised and recrystallised. No mineralisation recorded|16-MAY-23
78971|King Member|Geophysical Expression|Distinctive gamma log signature, showing monotonous low gamma counts. A few thin intervals with higher gamma counts denote sparse shale beds; these do not correlate well between boreholes.|16-MAY-23
78971|King Member|Geochemistry|Several major element and rare earth element analyses available (Tickell 2011b)|16-MAY-23
78971|King Member|Defn author|Steven J Tickell 3-OCT-2014|16-MAY-23
78971|King Member|Comments|As a result of a relog of cored drillhole NTGS 86/1, the contact between the newly defined Daly Basin units, Briggs and King members (of the Oolloo Dolostone) has been changed (very slightly) for both type sections.  Tim Munson 23-APR-2015|16-MAY-23
78971|King Member|References|Tickell SJ, 2002. Groundwater resources of the Oolloo Dolostone. Natural Resources Division, Northern Territory Department of Infrastructure, Planning and Environment, Technical Report 17/2002.***Tickell SJ, 2011a. Oolloo aquifer, 1:250,000 scale hydrogeological map. Natural Resources Division, Northern Territory Department of Infrastructure, Planning and Environment.***Tickell SJ, 2011b. Subsurface characteristics of the Oolloo Dolostone Natural Resources Division, Northern Territory Department of Infrastructure, Planning and Environment, Technical Report 28/2011.|16-MAY-23
80334|Kings Legend Metadolerite|Name source|Kings Legend copper occurrence (614763mE 7480370mN, GDA94, Zone53) in Jervois Range 1:100 000 mapsheet, Northern Territory.|16-MAY-23
80334|Kings Legend Metadolerite|Unit history|First defined as Kings Legend Amphibolite Member in Shaw et al (1985), used in Freeman et al (1986) as Kings Legend Amphibolite Member of the Bonya Schist.|16-MAY-23
80334|Kings Legend Metadolerite|Geomorphic expression|Ridges of rounded boulders and blocks, common pavements, often weathered rubble rills.|16-MAY-23
80334|Kings Legend Metadolerite|Type section locality|Bonya Hills (type area with 2 main localities): (1) porphyritic to glomerophyric metadolerite in eastern Bonya Hills in central-western Jervois Range 1:100 000 mapsheet at 614054mE 7484234mN, access on foot only; (2) equigranular metadolerite in western and northern Bonya Hills at 614499mE 7480626mN; access on foot only.|16-MAY-23
80334|Kings Legend Metadolerite|Extent|km-scale strike ridges, layers (sills, rare dykes) ranging in scale from <1m wide and m in length to 1 km wide and several km in length|16-MAY-23
80334|Kings Legend Metadolerite|General description|Regional variations: strongly porphyritic metadolerite with abundant plagioclase phenocrysts in a fine-grained hornblende matrix; sparsely porphyritic metadolerite; equigranular metadolerite; locally altered/metasomatised containing cm-scale euhedral almandine-rich garnet in strongly foliated amphibole-biotite±sillimanite matrix.|16-MAY-23
80334|Kings Legend Metadolerite|Thickness range|<1m to 1 km width.|16-MAY-23
80334|Kings Legend Metadolerite|Lithology|Porphyritic to glomerophyric metadolerite, primary igneous plagioclase phenocrysts in a very fine-grained granoblastic hornblende-plagioclase±quartz matrix; phenocrysts are tabular to equant and range in size from 0.5-1 cm in length; glomerocrysts are generally composed of three or four crystals and are up to 3 cm across; weakly- to moderately-developed grain shape foliation; (2) equigranular metadolerite, fine- to very fine-grained (aphanitic) assemblage of granoblastic hornblende-plagioclase±quartz; plagioclase is commonly laths; hornblende is acicular; fibrous actinolite; rare interstitial quartz; accessory titanite and magnetite.|16-MAY-23
80334|Kings Legend Metadolerite|Depositional environment|Continental margin environment, either arc cordillera or back arc basin, or derived from melting of pre-existing crust that formed in a continental margin environment.|16-MAY-23
80334|Kings Legend Metadolerite|Relationships and boundaries|Interpreted to form sills that intruded layer-parallel into the Bonya Metamorphics; minor dykes; now forming km-scale strike ridges; conformably interlayered with Mascotte Orthogneiss and White Violet Orthogneiss; locally intruded by Samarkand Pegmatite.|16-MAY-23
80334|Kings Legend Metadolerite|Identifying features|Glomerophyric.|16-MAY-23
80334|Kings Legend Metadolerite|Structure and Metamorphism|Weak to moderate grain shape foliation.|16-MAY-23
80334|Kings Legend Metadolerite|Age reasons|No absolute age constraints; interpreted to be coeval with Attutra Metagabbo; deformed  during regional tectonism at ca 1.76 Ga (LA-ICP-MS 207Pb/206Pb monazite, Reno et al 2016).|16-MAY-23
80334|Kings Legend Metadolerite|Correlations|Interpreted to be comagmatic and cogenetic with constituent units of the Casper Suite based on similar geochemical and isotopic composition, and timing of structural overprint.|16-MAY-23
80334|Kings Legend Metadolerite|Alteration and Mineralisation|Minor sericitisation, epidotisation, chloritisation; locally metasomatised; interpreted to be one of the main Cu-sources of scattered occurrences in the adjacent Bonya Metamorphics.|16-MAY-23
80334|Kings Legend Metadolerite|Geophysical Expression|Anomalous magnetic low signal; within area of gravity high signal; radiometric low signal.|16-MAY-23
80334|Kings Legend Metadolerite|Geochemistry|Basalt/gabbro, basaltic andesite/gabbroic diorite, rare andesite/diorite, minor granodiorite and tonalite; predominately calc-alkaline compositions, minor tholeiitic compositions; quartz-hypersthene normative, rarely olivine-normative; low-Ti, low-K, relatively flat REE patterns characterised by slight enrichment in LREE compared to MREE, negative Eu anomalies variably developed.|16-MAY-23
80334|Kings Legend Metadolerite|Defn author|Anett Weisheit, Barry Reno, Eloise Beyer (Northern Territory Geological Survey) 28-JUN-2018.|16-MAY-23
80334|Kings Legend Metadolerite|Proposed publication|Weisheit A, Reno BL and Beyer EE, in review. Jervois Range Special, Northern Territory. 1:100 000 geological map explanatory notes, 6152 and part 6252. Northern Territory Geological Survey, Darwin.|16-MAY-23
80334|Kings Legend Metadolerite|References|Freeman MJ, Black LA, Offe LA, Senior BR, Shaw RD, Shergold JH, Simpson CJ, Walter MR, Warren RG, Donnellan N, Horsfall CJ, Laurie JR and Walley AM, 1986. Huckitta, Northern Territory (Second Edition). 1:250 000 geological map series, SF 53-11. Northern Territory Geological Survey, Darwin.**Reno BL, Whelan JA, Weisheit A, Kraus S, Beyer EE, Meffre S and Thompson J, 2016. Summary of Results. NTGS laser ablation ICP-MS in situ monazite geochronology project: Arunta Region, July 2013-June 2014. Northern Territory Geological Survey, Record.  **Shaw RD, Warren RG and Freemann MJ, 1985. Stratigraphic definitions of named units in the Arunta Block, Northern Territory, 1979-82. Bureau of Mineral Resources, Australia, Report 260.|16-MAY-23
72419|Koonoonyeri Granite|Name source|After Koonoonyeri Bore (53K 258775mE 7592200mN) in MOUNT PEAKE|16-MAY-23
72419|Koonoonyeri Granite|Unit history|Mapped as unnamed Carpentarian granite Pgp on First Edition MOUNT PEAKE (Offe 1978).|16-MAY-23
72419|Koonoonyeri Granite|Geomorphic expression|Whalebacks and bouldery nubbins.|16-MAY-23
72419|Koonoonyeri Granite|Type section locality|In vicinity of 263263mE 7574234mN (21o55'07"S 132o42'34"E) in MOUNT PEAKE.|16-MAY-23
72419|Koonoonyeri Granite|Extent|North of Anzac Dam Fault Zone in southern-central MOUNT PEAKE, particularly proximal to Nanga Range. Interpreted from airborne magnetic and regional gravity data to extend over an area of ~1500 km2.|16-MAY-23
72419|Koonoonyeri Granite|Lithology|Grey biotite granite characterised by equant K-feldspar megacrysts; locally mylonitic or phyllonitic. A discrete, high-U variant (Pgk1) is mapped separately and is characteristically deeply weathered in outcrop. This variant outcrops immediately east of Nanga Range (eg 263250mE 7586000mN).|16-MAY-23
72419|Koonoonyeri Granite|Relationships and boundaries|Locally intrudes probable Lander Rock Formation (in vicinity of 262500mE 7572250mN). Unconformably overlain by Vaughan Springs Quartzite.|16-MAY-23
72419|Koonoonyeri Granite|Age reasons|Statherian, based on SHRIMP single-crystal zircon U-Pb igneous crystallisation age of 1793 ± 3 Ma (KE Worden, pers comm 2005).|16-MAY-23
72419|Koonoonyeri Granite|Correlations|Comparable in age to Anmatjira Orthogneiss which has an igneous crystallisation age of 1795 ± 3 Ma (KE Worden, pers comm 2006); however, Anmatjira Orthogneiss contrasts with Koonoonyeri Granite in that former is a rapakivi granite. Esther and Koonoonyeri Granites are same age within error. However, Esther Granite is interpreted to be syn-tectonic with respect to Stafford Event and Koonoonyeri Granite late to post-tectonic with respect to this same event.|16-MAY-23
72419|Koonoonyeri Granite|References|Offe LA, 1978. Mount Peake, Northern Territory. 1:250 000 geological series explanatory notes, SF 53-5. Bureau of Mineral Resources, Australia, Canberra.|16-MAY-23
24345|Kudinga Basalt|Name source|Kudinga Creek in NE Davenport Range 1:100 000 Sheet area, Bonney Well 1:250 000 Sheet area.|16-MAY-23
24345|Kudinga Basalt|Type section locality|About 3 km SSE of Coulters Waterhole (latitude 20o59'55"S, longitude 135o01'50"E, Hatches 1:100 000 Sheet area), in NW of Elkedra 1:100 0000 Sheet area, Elkedra 1:250 000 Sheet area. Base at GR 038754, top at GR 042755. Here, the formation is about 400 m thick, dips about 55oE, and consists of basalt lava a few metres thick at the base  (overling the Frew River Formation), overlain by two bands of ridge-forming arenite and an intervening recessive band, total thickness about 100 m, and about 300 m of basalt. Overlain by ridge-forming Errolola Sandstone.|16-MAY-23
24345|Kudinga Basalt|Extent|Throughout Davenport Province: E and central parts of Bonney Well, SW part of Frew River, NW part of Elkedra, NE part of Barrow Creek 1:250 000 Sheet areas.|16-MAY-23
24345|Kudinga Basalt|Thickness range|Generally between 100 m and 800 m.|16-MAY-23
24345|Kudinga Basalt|Lithology|Recessive amygdaloidal and scoriaceous to massive basalt; rare pillows; minor bands of ridge-forming quartz arenite and feldspathic/lithic arenite commonly present in lower part; rare tuffaceous siltstone.|16-MAY-23
24345|Kudinga Basalt|Relationships and boundaries|Conformably overlies Frew River Formation, or where this is absent, Coulters Sandstone. Conformably overlain by Errolola Sandstone. Base taken at base of first basalt lava above recessive Frew River Formation or above ridge-forming arenite overlying the Frew River Formation. Top taken at top of uppermost basalt lava.|16-MAY-23
24345|Kudinga Basalt|Age reasons|Between 1870 Ma (U-Pb date on zircon in volcanics of the Warramunga Group, which is unconformable below the Hatches Creek Group), and 1640 Ma (Rb-Sr whole-rock approximate date on granite intruding Hatches Creek Group).|16-MAY-23
24345|Kudinga Basalt|Comments|Remarks: Youngest formation of Wauchope Subgroup of Hatches Creek Group. Distinctive region-wide marker unit.|16-MAY-23
24345|Kudinga Basalt|Defn Reference|Defined 86/25362|16-MAY-23
24345|Kudinga Basalt|Proposer|Stewart A.J.|16-MAY-23
24345|Kudinga Basalt|Resdate|07-OCT-1981|16-MAY-23
75502|Kukalak Gneiss|Name source|After the Kukalak region (Warddeken Indigenous Area), Alligator River and Milingimbi 1:250 000 scale mapsheets, western Arnhem Land, Northern Territory. Subsequently became an Exploration Licence name (EL3421 - Kukalak). The tenement area was located within longitudes 133o25'E and 133o35'E and latitudes  12o25'S and 12o40'S; Howship, Oenpelli and Liverpool 1:100 000 scale mapsheets.|16-MAY-23
75502|Kukalak Gneiss|Unit history|Previously known as part of Myra Falls Metamorphics and also previously mapped as Nimbuwah Complex in the Caramal Inlier. The name 'Myra Falls Metamorphics' was first introduced by Dunn (1962) to describe metamorphic rocks in the Oenpelli area (now often referred to as Kunbarllanjnja or Gunbalanya) which were then considered to be Archaean. Subsequent work by Needham et al (1974) suggested these rocks were Palaeoproterozoic. The name 'Myra Falls Metamorphics' is abandoned, as it is now known to comprise components of the Palaeoproterozoic Kakadu Group, Cahill Formation and Neoarchaean gneissic basement (Hollis et al 2009, in press).|16-MAY-23
75502|Kukalak Gneiss|Unit history|Previously known as part of the Myra Falls Metamorphics. The name 'Myra Falls Metamorphics' was first introduced by Dunn (1962) to describe metamorphic rocks in the Oenpelli area (now often referred to as Kunbarllanjnja or Gunbalanya) which were then considered to be Archaean. Subsequent work by Needham et al (1974) suggested these rocks were Palaeoproterozoic. The name 'Myra Falls Metamorphics' is abandoned, as it is now known to comprise components of the Palaeoproterozoic Kakadu Group, Cahill Formation and Neoarchaean gneissic basement (Hollis et al 2009a, b).|16-MAY-23
75502|Kukalak Gneiss|Geomorphic expression|Low-lying areas exposed in creek systems. Exposures have white tones in aerial photographs.|16-MAY-23
75502|Kukalak Gneiss|Type section locality|Sporadically exposed river-polished platform along creek beds in Tin Camp Creek in eastern Myra Falls Inlier, western Arnhem Land, Northern Territory. Alligator River 1:250 000 mapsheet, Oenpelli 1:100 000 mapsheet. Grid reference, GDA 94, 53L 318354mE 8622428mN (-12°27'22"S 133°19'43"E).|16-MAY-23
75502|Kukalak Gneiss|Type section locality|River-polished platform along creek beds in Tin Camp Creek in eastern Myra Falls Inlier, western Arnhem Land, Northern Territory. Alligator River 1:250 000 scale mapsheet, Howship 1:100 000 scale mapsheet. Grid reference:  12o27'22.33"S, 133o19'43.39"E (GDA 94, Zone 53, 318354mE 8622428mN).|16-MAY-23
75502|Kukalak Gneiss|Description at type locality|Highly-strained, felsic layered biotite quartzo-feldspathic orthogneiss with subordinate discontinuous amphibolite. Relict plagioclase phenocrysts and flattened and attenuated plagioclase augen are locally preserved in low-strain asymmetric boudins and small accumulations of leucocratic melt segregations occur in dilational boudin necks.|16-MAY-23
75502|Kukalak Gneiss|Extent|Alligator River and Cobourg Peninsula 1:250 000 scale mapsheets, Nimbuwah Domain, Pine Creek Orogen, western Arnhem Land, Northern Territory. Occurs as exposed and subcropping gneiss in Myra Falls and Caramal inliers and also under extensive Cretaceous cover in Wellington Range region of Cobourg Peninsula|16-MAY-23
75502|Kukalak Gneiss|Thickness range|Unknown due to poor exposure|16-MAY-23
75502|Kukalak Gneiss|Lithology|High-strain, felsic-layered biotite quartzo-feldspathic orthogneiss with subordinate discontinuous amphibolite. Relict plagioclase phenocrysts and flattened and attenuated plagioclase augen are locally preserved in low-strain asymmetric boudins and small accumulations of leucocratic melt segregations occur in dilational boudin necks.|16-MAY-23
75502|Kukalak Gneiss|Depositional environment|Genesis: Intrusive|16-MAY-23
75502|Kukalak Gneiss|Relationships and boundaries|Structurally underlies Palaeoproterozoic metasedimentary Kudjumarndi Quartzite of the Kakadu Group (Hollis et al 2009c).  Physical boundaries with overlying units are not observed due to generally poor outcrop. The exact nature of unit boundaries is not possible to define, due to poor exposure and structural transposition by later Palaeoproterozoic tectonism|16-MAY-23
75502|Kukalak Gneiss|Relationships and boundaries|The Kukalak Gneiss consists of sporadically exposed water-polished platforms along creek beds in the Myra Falls Inlier. It consists of basement rock that structurally underlies the Palaeoproterozoic metasedimentary Kudjumarndi Quartzite of the Kakadu Group.  Physical boundaries with overlying units are not observed due to generally poor outcrop. The exact nature of the unit boundaries is not possible to define, even in drillholes, due to poor exposure and structural transposition by later Palaeoproterozoic tectonism; however, an unconformable contact is inferred. Stratigraphic relationships are described in detail in Hollis et al (in press)|16-MAY-23
75502|Kukalak Gneiss|Identifying features|The Kukalak Gneiss is distinguished from younger Palaeoproterozoic Nimbuwah granitoids by distinctive metamorphic fabrics, e.g. well developed gneissosity and a strongly developed shallow east-plunging mineral stretching lineation. In the type area, S2 is crenulated by minor tight, to isoclinal, upright, shallow east-plunging, northwest-vergent F2 folds, Hollis et al (in press). It also has a distinctive geochemical signature, characterised by depletion in heavy rare earth elements relative to light rare earth elements (Glass et al 2009).|16-MAY-23
75502|Kukalak Gneiss|Structure and Metamorphism|Kukalak Gneiss has distinctive metamorphic fabrics, e.g. well developed gneissosity and a strongly developed shallow east-plunging mineral stretching lineation. In the type area, S2 is crenulated by minor tight, to isoclinal, upright, shallow east-plunging, northwest-vergent F2 folds, Hollis et al (2009c).|16-MAY-23
75502|Kukalak Gneiss|Age reasons|U-Pb SHRIMP zircon ages of 2527 +/- 3 Ma and 2510 +/- 4 Ma, (Hollis et al 2008, 2009), interpreted to represent the primary magmatic crystallisation age of the gneissic protoliths.|16-MAY-23
75502|Kukalak Gneiss|Correlations|Nanambu Complex (ca 2470 Ma; Page et al 1980) in Nimbuwah Domain of Pine Creek Orogen, west Arnhem Land; Rum Jungle Complex (2545-2521 Ma; Cross et al 2005) in Central Domain of Pine Creek Orogen; Billabong Complex (2514 +/- 3 Ma; Page et al 1995) in Tanami Region and possibly Black Angel Gneiss (ca 2.50-2.42 Ga; McDonald et al 1997) in western Mount Isa region, Queensland.|16-MAY-23
75502|Kukalak Gneiss|Correlations|Nanambu Complex (2520 +/- 3 Ma; Hollis et al 2009c, Carson et al 2010, ca 2470 Ma; Page et al 1980) in Nimbuwah Domain of Pine Creek Orogen, west Arnhem Land; Rum Jungle Complex (2545-2521 Ma; Cross et al 2005) in Central Domain of Pine Creek Orogen; Billabong Complex (2514 +/- 3 Ma; Page et al 1995) in Tanami Region and possibly Black Angel Gneiss (ca 2.50-2.42 Ga; McDonald et al 1997) in western Mount Isa region, Queensland.|16-MAY-23
75502|Kukalak Gneiss|Alteration and Mineralisation|Sericite alteration of feldspar. No known mineralisation.|16-MAY-23
75502|Kukalak Gneiss|Geochemistry|Kukalak Gneiss has a distinctive geochemical signature relative to the Palaeoproterozoic Nimbuwah Complex, characterised by depletion in HREE relative to LREE (Glass et al 2009) and is peraluminous. epsilonNd isotopes for samples of the Kukalak Gneiss are consistently within one epsilon unit, slightly less than Chondritic Uniform Reservoir (CHUR, Glass et al 2010).|16-MAY-23
75502|Kukalak Gneiss|Defn author|Hollis, J. (NTGS)  28-AUG-2009|16-MAY-23
75502|Kukalak Gneiss|Defn author|Hollis, J.A.,  and Glass, L.M. (NTGS),  03-NOV-2010|16-MAY-23
75502|Kukalak Gneiss|Comments|Redefinition provides additional information, including some new dates and more published references.|16-MAY-23
75502|Kukalak Gneiss|References|**CROSS, A.J., Claoue-Long, J.C., Scrimgeour, I.R., Ahmad, M. and Kruse, P.D., 2005. Summary of results. Joint NTGS-GA geochronology project: Rum Jungle, basement to southern Georgina Basin and eastern Arunta Region 2001-2003. Northern Territory Geological Survey, Record 2005-006    **DUNN, P.R., 1962. Alligator River, Northern Territory. 1:250 000 geological series explanatory notes, SD53-01. Bureau of Mineral Resources, Australia, Canberra.    **GLASS L.M., Hollis J.A. and Carson C.J., 2009. Geochemical and isotopic discrimination methods for Neoarchaean and Palaeoproterozoic rocks in western Arnhem Land, Pine Creek Orogen: Applications for uranium exploration: in Annual Geoscience Exploration Seminar (AGES). Record of Abstracts. Northern Territory Geological Survey, Record 2009-002.     **HOLLIS, J.A, Carson, C.J. and Glass, L.M., 2008. The discovery of an Archaean Inlier in Arnhem Land. Annual Geoscience Exploration Seminar (AGES). Record of Abstracts. Northern Territory Geological Survey, Record 2008-002.    **HOLLIS J.A., Carson C.J. and Glass L.M., 2009. Extensive exposed Neoarchaean crust in Arnhem Land, Pine Creek Orogen: U-Pb zircon SHRIMP geochronology: in Annual Geoscience Exploration Seminar (AGES). Record of Abstracts. Northern Territory Geological Survey, Record 2009-002.    **HOLLIS J.A., Carson C.J. and Glass L.M., in press. SHRIMP U-Pb zircon geochronological evidence for Neoarchaean basement in western Arnhem Land, northern Australia. Precambrian Research    **McDONALD, G.D., Collerson K.D. and Kinny, P.D., 1997. Late Archean and Early Proterozoic crustal evolution of the Mount Isa block, northwest Queensland, Australia. Geology, 25(12), 1095-1098.    **NEEDHAM, R.S, Smart, P.G. and Watchman, A.L., 1974. A Reinterpretation of the geology of the Alligator Rivers uranium field, N.T. Search, 5(8), 397-399.    **PAGE, R.W., Compston, W. and Needham, R.S., 1980. Geochronology and evolution of the late-Archaean basement and Proterozoic rocks in the Alligator Rivers uranium field, Northern Territory, Australia: in Ferguson, J., Goleby, A.B. (editors) Uranium in the Pine Creek Geosyncline: Proceedings of the international uranium symposium on the Pine Creek Geosyncline. International Atomic Energy Agency, Vienna, 39-68.    **PAGE, R.W., Sun, S-s. and Blake, D., 1995. Geochronology of an exposed late Archaean basement terrane in The Granites-Tanami region. AGSO Research Newsletter, 22, 20.|16-MAY-23
75502|Kukalak Gneiss|References|**CARSON CJ, Hollis JA, Glass LM, Close DF, Whelan JA and Wygralak A, 2010. Summary of results. Joint NTGS-GA geochronology project: East Arunta Region, Pine Creek Orogen and Murphy Inlier, July 2007-June 2009. Northern Territory Geological Survey, Record 2010-004.    **CROSS, A.J., Claoué-Long, J.C., Scrimgeour, I.R., Ahmad, M. and Kruse, P.D., 2005. Summary of results. Joint NTGS-GA geochronology project: Rum Jungle, basement to southern Georgina Basin and eastern Arunta Region 001-2003. Northern Territory Geological Survey, Record 2005-006.    **DUNN, P.R., 1962. Alligator River, Northern Territory. 1:250 000 geological series explanatory notes, SD53¿01. Bureau of Mineral Resources, Australia, Canberra.    **GLASS L.M., Hollis J.A. and Carson C.J., 2009. Geochemical and isotopic discrimination methods for Neoarchaean and Palaeoproterozoic rocks in western Arnhem Land, Pine Creek Orogen: Applications for uranium exploration: in Annual Geoscience Exploration Seminar (AGES). Record of Abstracts. Northern Territory Geological Survey, Record 2009-002.     **GLASS LM, Hollis JA, Carson CJ, Yaxley G and Armstrong R, 2010. Archaean and Palaeoproterozoic crustal evolution processes in the Pine Creek Orogen: U-Pb, Hf, O and Nd isotopic data and geochemistry: in 'Annual Geoscience Exploration Seminar (AGES) 2010. Record of Abstracts.' Northern Territory Geological Survey, Record 2010-002    **HOLLIS JA, Carson CJ and Glass LM, 2008. The discovery of an Archaean Inlier in Arnhem Land: in 'Annual Geoscience Exploration Seminar (AGES) 2008. Record of Abstracts.' Northern Territory Geological Survey, Record 2008-002.    **HOLLIS J.A., Carson C.J. and Glass L.M., 2009a. Extensive exposed Neoarchaean crust in Arnhem Land, Pine Creek Orogen: U-Pb zircon SHRIMP geochronology: in Annual Geoscience Exploration Seminar (AGES). Record of Abstracts. Northern Territory Geological Survey, Record 2009-002.    **HOLLIS, J., Schérsten, A., Glass, L.M., Carson, C.J., 2009b. Stratigraphic and tectonic evolution of the Nimbuwah Domain: a separate terrane to the rest of the Pine Creek Orogen? Annual Geoscience Exploration Seminar (AGES). Record of Abstracts. Northern Territory Geological Survey, Record 2009-002.    **HOLLIS J, Carson C and Glass L, 2009c. SHRIMP U-Pb zircon geochronological evidence for Neoarchean basement in western Arnhem Land, northern Australia. Precambrian Research 174(3-4), 364-380.    **McDONALD, G.D., Collerson K.D. and Kinny, P.D., 1997. Late Archean and Early Proterozoic crustal evolution of the Mount Isa block, northwest Queensland, Australia. Geology, 25(12), 1095-1098.    **NEEDHAM, R.S, Smart, P.G. and Watchman, A.L., 1974. A Reinterpretation of the geology of the Alligator Rivers uranium field, N.T. Search, 5(8), 397-399.    **PAGE, R.W., Compston, W. and Needham, R.S., 1980. Geochronology and evolution of the late-Archaean basement and Proterozoic rocks in the Alligator Rivers uranium field, Northern Territory, Australia: in Ferguson, J., Goleby, A.B. (editors) Uranium in the Pine Creek Geosyncline: Proceedings of the international uranium symposium on the Pine Creek Geosyncline. International Atomic Energy Agency, Vienna, 39¿68.    **PAGE, R.W., Sun, S-s. and Blake, D., 1995. Geochronology of an exposed late Archaean basement terrane in The Granites-Tanami region. AGSO Research Newsletter, 22, 20.|16-MAY-23
33810|Kulail Sandstone|Name source|Kulail Outstation, central western edge of Hull 1:100 000 mapsheet.|16-MAY-23
33810|Kulail Sandstone|Unit history|Formerly mapped as part of Dean Quartzite (Forman 1966).|16-MAY-23
33810|Kulail Sandstone|Constituents|Nil.|16-MAY-23
33810|Kulail Sandstone|Geomorphic expression|Cliffs and scarps on south face of Dean, Bloods and Rowley Ranges, low scrubby hills in the west between Kulail and Puntitjata Outstation.|16-MAY-23
33810|Kulail Sandstone|Type section locality|Southern slope of Bloods Range, 11 km west of Mount Harris at location 24? 38' 02.97" S, 129? 24' 18.4" E (WGS 84). Lower stratigraphic contact is an erosional unconformity defined by Kulail Sandstone overlying interlayered quartz sandstone and red shale beds with the upper 50 cm as leached clay. Upper stratigraphic contact is gradational with interlayered beds of quartz gravel to pebble in a quartzofeldspathic matrix increasingly interlensed with clean, equigranular beds of quartz sandstone. Approximate thickness of section is 100m.|16-MAY-23
33810|Kulail Sandstone|Extent|Western and central northern areas on Hull 1:100 000 mapsheet and central northwestern Bloods Range 1:100 000 mapsheet.|16-MAY-23
33810|Kulail Sandstone|Thickness range|Variable. Appears to thin from a minimum 150m on the southern edge of Bloods Range to 60m on the southern edge of the Rowley Range.|16-MAY-23
33810|Kulail Sandstone|Lithology|Quartz sandstone, sometimes gritty, quartzofeldspathic sandstone, and minor quartzite. Possible rare, poorly preserved mafic volcanics.|16-MAY-23
33810|Kulail Sandstone|Depositional environment|Alluvial to shallow marine, possibly deltaic.|16-MAY-23
33810|Kulail Sandstone|Relationships and boundaries|Conformably overlain by/grades up into Dean Quartzite. Disconformably overlies Bloods Range Formation.|16-MAY-23
33810|Kulail Sandstone|Age reasons|Similar age to Dean Quartzite ~850 Ma.|16-MAY-23
33810|Kulail Sandstone|Correlations|Nil|16-MAY-23
33810|Kulail Sandstone|Proposed publication|Close, D.F., Edgoose, C.J., Scrimgeour, I.R., 2002. Bloods Range and Hull 1:100 000 geological special, Northern Territory Geological Survey, Explanatory notes.|16-MAY-23
33810|Kulail Sandstone|References|Forman, D.J., 1966. Bloods Range Northern Territory 1:250 000 geological series explanatory notes. Sheet (SG53-3). Bureau of Mineral Resources, Australia.|16-MAY-23
33489|Kulu Granite|Name source|Kulu, Aboriginal name for rocky hill 10 km south of Foster Cliff at 25o40'33.9"S, 130o25'54.8"E, Petermann Ranges.|16-MAY-23
33489|Kulu Granite|Unit history|Comprises unnamed metamorphosed granites and Olio Gneiss of Forman (1966, 1972).|16-MAY-23
33489|Kulu Granite|Constituents|Nil. Forms part of the Mantarurr Granite Suite.|16-MAY-23
33489|Kulu Granite|Geomorphic expression|Low outcrops and rounded rocky and bouldery hills.|16-MAY-23
33489|Kulu Granite|Type section locality|15 km south of Foster Cliff 25o43'43.3"S, 130o24'16.6"E.|16-MAY-23
33489|Kulu Granite|Extent|Main area of outcrop is a 10 x 12 km region 6-15 km south of Foster Cliff, as well as smaller bodies in the vicinity of Foster Cliff and 18 km south-southwest of Foster Cliff.|16-MAY-23
33489|Kulu Granite|Lithology|Coarsely porphyritic foliated biotite granite with coarse phenocrysts of both K-feldspar and plagioclase which are typically 1-3 cm in diameter. Plagioclase phenocrysts are often a pale green colour and are smaller than the K-feldspar phenocrysts. The matrix is medium grained and consists of quartz, feldspar, biotite, epidote, sphene and muscovite, with less abundant ilmenite and garnet.|16-MAY-23
33489|Kulu Granite|Relationships and boundaries|Intrudes 1600-1550 Ma amphibolite gneiss and locally contains large xenoliths of the gneiss. Has sharp intrusive contacts with the Foster Cliff Granite with no clear timing relationships. Intruded by mafic dykes of the Alcurra and/or Amata Dyke Swarms.|16-MAY-23
33489|Kulu Granite|Age reasons|Mesoproterozoic. SHRIMP U-Pb zircon age of c.1168 +/- 14 Ma (M Fanning, pers. Comm.)|16-MAY-23
33489|Kulu Granite|Correlations|Geochemically and mineralogically similar to the Utanta Granite, Wala Wuru Granite and Foster Cliff Granite. Similar age, but geochemically distinct from the Pottoyu and Umutju Granite Suites and Walal Granite on Petermann Ranges.|16-MAY-23
33489|Kulu Granite|Proposed publication|Petermann Ranges 1:250 000 geological mapsheet Explanatory Notes.|16-MAY-23
33489|Kulu Granite|Category|2|16-MAY-23
33489|Kulu Granite|Defn approved by|Beier P., Kruse P.D., Young D.N.|16-MAY-23
33489|Kulu Granite|Proposer|Scrimgeour I.R., Close D.F., Edgoose C.J.|16-MAY-23
33489|Kulu Granite|Resdate|13-NOV-1996|16-MAY-23
24347|Kurinelli Sandstone|Name source|Kurinelli gold mine, GR 036130, Hatches 1:100 000 Sheet area, Frew River 1:250 000 Sheet area.|16-MAY-23
24347|Kurinelli Sandstone|Type section locality|From GR 030206 (base), 2.5 km NNW of Kurinelli mine (latitude 20o38'00"S, longitude 135o02'00"E) in Hatches 1:100 000 Sheet area, where the formation is conformable on Rooneys Formation, west to GR 992204 in Davenport Range 1:100 000 Sheet area, and SW through GR 960185 to GR 939147 (top), where it is overlain conformably by Taragan Sandstone. The type section thus transects some 11.5 km of low ridges containing gently to moderately-dipping Kurinelli Sandstone, which here is about 3000 m thick, and consists of fine to medium, thin to thick bedded arenite with some medium to coarse and gritty interbeds in upper part and laminated siltstone and claystone near base.|16-MAY-23
24347|Kurinelli Sandstone|Extent|Throughout the Davenport Province - eastern and central parts of Bonney Well, southwestern part of Frew River, northwestern part of Elkedra, and northeastern part of Barrow Creek 1:250 000 Sheet areas.|16-MAY-23
24347|Kurinelli Sandstone|Thickness range|0 to at least 3000 m.|16-MAY-23
24347|Kurinelli Sandstone|Lithology|Brown weaathering fine to medium, clay-grain rich (?kaolinised feldspar) arenite, strongly cross-bedded in places, thin to medium-bedded, some medium to coarse and gritty interbeds of lithic arenite, particularly in upper part; minor quartzosed arenite, siltstone, claystone, slate and intermediate to felsic volcanics. Interlaminated claystone, siltstone and fine arenite form mappable member (Endurance Sandstone Member) near base in southern Hatches 1:100 000 Sheet area, and non-bedded quartzose arenite forms mappable member (Warnes Sandstone Member) in upper part of the formation in southern Hatches, southeastern Davenport Range (Bonney Well 1:250 000 Sheet area) and northeastern Murray Downs (Barrow Creek 1:250 000 Sheet area) 1:100 000 Sheet areas.|16-MAY-23
24347|Kurinelli Sandstone|Relationships and boundaries|Conformable on, and interfingers with, Rooneys Formation, Epenarra Volcanics and Edmirringee Volcanics; overlain conformably by, and probably also interfingers with, pebbly arenite and conglomerate of Taragan Sandstone; overlain conformably by more quartzose arenite of Unimbra Sandstone and unconformably by Cambrian beds. Intruded by sill-like bodies of granophyre and dolerite/gabbro, and by plutons of Devils Marbles Granite and unnamed granite.|16-MAY-23
24347|Kurinelli Sandstone|Age reasons|Younger than 1870 m.y. - U-Pb zircon age of volcanics in the Warramunga Group unconformably underlying the Hatches Creek Group. Older than 1640 m.y. - Rb-Sr whole-rock age of granite intruding the Hatches Creek Group.|16-MAY-23
24347|Kurinelli Sandstone|Comments|Remarks: Part of the Ooradidgee Subgroup of the Hatches Creek Group. Includes the Endurance Sandstone Member and Warnes Sandstone Member, two lensoid units of distinctive, readily mappable lithology.|16-MAY-23
24347|Kurinelli Sandstone|Defn Reference|Defined 86/25362|16-MAY-23
24347|Kurinelli Sandstone|Proposer|Sweet I.P.|16-MAY-23
24347|Kurinelli Sandstone|Resdate|07-OCT-1981|16-MAY-23
9937|Kurrundie Sandstone|Name source|Kurrundie Creek, latitude 13o31'S, longitude 132o29'E, Ranford Hill 1:100 000 Sheet area.|16-MAY-23
9937|Kurrundie Sandstone|Unit history|Previously called the Kurrundi(e) Member of the Kombolgie Formation by Walpole & others (1968).|16-MAY-23
9937|Kurrundie Sandstone|Type section locality|Kurrundie Creek, latitude 13o31'S, longitude 132o29'E. From GR 285025 to GR 280055 (Ranford Hill 1:100 000 Sheet area).|16-MAY-23
9937|Kurrundie Sandstone|Extent|Headwaters of the South Alligator and Mary Rivers. Semi-continuous ridge surrounding Mount Callanan extending from 2 km northwest of Bloomfield Spring (Ranford Hill 1:100 0000 Sheet) to 3 km northeast of the old Goodparla Homestead (Mundogie 1:100 000 Sheet), to aabout 12 km west of Sleisbeck (Stow 1:100 000 Sheet area).|16-MAY-23
9937|Kurrundie Sandstone|Thickness range|Range 50-350 m.|16-MAY-23
9937|Kurrundie Sandstone|Lithology|Purple clayey quartz sandstone, brown and white, fine to coarse quartz sandstone, minor micaceous sandy siltstone, shale. Polymictic cobble conglomerate at base forms beds up to 50 m thick.|16-MAY-23
9937|Kurrundie Sandstone|Relationships and boundaries|Unconformably overlies metamorphosed Early Proterozoic sediments (1800 m.y.) and El Sherana Group. Conformably overlain by Plum Tree Creek Volcanics. A basal unit in the Edith River Group probably equivalent to the Phillips Creek Sandstone and Hindrance Creek Sandstone.|16-MAY-23
9937|Kurrundie Sandstone|Age reasons|Late Early Proterozoic (1780-1650 m.y.) as the Group unconformably overlies the Cullen Granite Complex (1780-1730 m.y.) and is younger than the Kombolgie Formation (1650 m.y.) which unconformably overlies the Edith River Group.|16-MAY-23
9937|Kurrundie Sandstone|Proposed publication|Geological map Commentary, Mundogie 1:100 000 Sheet|16-MAY-23
83010|Kurt Johanssen Granite|Name source|Kurt Johanssen Granite is named after the Kurt Johanssen Truck Parking Bay (GDA94, 53K, 677970mE, 7781550mN), which lies approximately 15 km to the east of the mapped undercover extent of this unit.|16-MAY-23
83010|Kurt Johanssen Granite|Unit history|Referred to as `alkali-feldspar granite? by Pellatt and Fulton (2012).|16-MAY-23
83010|Kurt Johanssen Granite|Geomorphic expression|No known outcrops.|16-MAY-23
83010|Kurt Johanssen Granite|Type section locality|Drillhole WNWE029, down-hold depth from 116 m to 156 m (EOH). Drillhole location 641396mE 7773092mN (MGA94 zone 53) / 20.134212S 136.352764E. Note: this drillhole was drilled using reverse circulation. No drill core is available. The present location of drill chips is unknown.|16-MAY-23
83010|Kurt Johanssen Granite|Description at type locality|Drill chips consisting of strongly foliated, porphyritic, alkali-feldspar granite containing quartz, orthoclase feldspar, sericite/illite (secondary), plagioclase feldspar and apatite (Spring 2009; Pellatt and Fulton, 2012). The present location of the drill chips is unknown.|16-MAY-23
83010|Kurt Johanssen Granite|Extent|Does not outcrop, but distinct geophysical characteristics (see below) allow this unit to be mapped undercover. It forms a large (over 100 km in length), irregular body in the southeast and northeast of the ALROY and FREW RIVER mapsheets, respectively (Clark et al., 2021).|16-MAY-23
83010|Kurt Johanssen Granite|General description|Only known in the type interval. See description above.|16-MAY-23
83010|Kurt Johanssen Granite|Thickness range|This unit was intersected across 40 metres of drillhole WNWE029, the entire basement intersection of this drillhole (Pellatt and Fulton, 2012). However, this unit is characterised by a low in regional gravity data that is tens of kilometres across, and its true thickness is likely to be substantial.|16-MAY-23
83010|Kurt Johanssen Granite|Lithology|Strongly foliated, porphyritic, alkali-feldspar granite containing quartz, orthoclase feldspar, sericite/illite (secondary), plagioclase feldspar and apatite (Spring 2009; Pellatt and Fulton, 2012).|16-MAY-23
83010|Kurt Johanssen Granite|Relationships and boundaries|Unknown.|16-MAY-23
83010|Kurt Johanssen Granite|Identifying features|This unit can be distinguished on the basis of being a strongly foliated felsic intrusive, with potassium feldspar phenocrysts, that is less dense than the Alroy Formation and is homogeneously non-magnetic in regional aeromagnetics data, and having an age of approximately 1838 Ma (see below).|16-MAY-23
83010|Kurt Johanssen Granite|Structure and Metamorphism|Other than a foliation observed in drilling chips, no direct structural or metamorphic information is available for this unit. Geophysical imagery indicate that this unit may cross-cut folding in the Alroy Formation, and that the intrusion is cross-cut by regional shear zones (Clark et al., 2021).|16-MAY-23
83010|Kurt Johanssen Granite|Age reasons|Eleven LA-ICPMS analyses of zircon grains separated from this unit gave an interpreted 207Pb/206Pb intrusive age of 1838 +/-12 Ma (Pellatt and Fulton, 2012; R. Fulton, pers. comm., 2021).|16-MAY-23
83010|Kurt Johanssen Granite|Alteration and Mineralisation|Unknown.|16-MAY-23
83010|Kurt Johanssen Granite|Geophysical Expression|Down-hole geophysical data are not available for this unit. Regional magnetics and gravity data indicate that this unit is characterised by relatively homogenous low magnetic susceptibility and a density that is lower than the Alroy Formation.|16-MAY-23
83010|Kurt Johanssen Granite|Defn author|A.D. Clark 24-MAR-2022.|16-MAY-23
83010|Kurt Johanssen Granite|Proposed publication|Schofield and Clark et al., (in prep). Geology of the East Tennant area, Northern Territory, journal publication.|16-MAY-23
83010|Kurt Johanssen Granite|Comments|Likely I-type affinity, similar to other constituents of the Mount Lamb Suite. Description of unit is taken from company reports and unpublished petrological reports. The clear geophysical and geochronological evidence for the presence of this unit, along with the large regional extent, justifies the naming of the unit. The present location of any remaining drill chips from this unit is not known.|16-MAY-23
83010|Kurt Johanssen Granite|References|Spring, K. E., 2009. Petrographic reports on four drill chip samples from Wonerah basement rocks, unpublished petrographic report by Geochempet Services, Maleny.   **Pellatt, A., and Fulton, R., 2012. Grouped Annual Report (GR-097/09) for EL 9979, EL 24607, EL 26185, EL 26584, EL 26585, EL 26586, EL 26589, EL 28233, SEL 26451 and SEL 26452 (Wonarah Phosphate Project) for the period ending 8 January 2012, Company report published by the Northern Territory Geological Survey (Report ID CR2012-0053).  **Clark, A., Highet, L., Schofield, A., Doublier, M., 2021. Solid Geology map of the East Tennant region, dataset, Geoscience Australia.|16-MAY-23
28264|Lake Surprise Sandstone|Name source|Lake Surprise, latitude 20o14'S, longitude 131o48'E, Mount Solitaire 1:250 000 Sheet SF/52-4.|16-MAY-23
28264|Lake Surprise Sandstone|Unit history|Mapped previously ;(Milligan et al., 1966) as Dulcie Sandstone.|16-MAY-23
28264|Lake Surprise Sandstone|Type section locality|The interval from 3 m to 62 m in stratigraphic drillhole BMR Lander River 1, latitude 20o31'S, longitude 133o30'E, Lander River 1:250 000 Sheet area SF53-1 (Kennewell & Huleatt, in prep.). Lithology uniform throughout type section, consisting of sandstone, white to light brown, very fine to medium grained, well rounded, well sorted, commonly bimodally sorted with silt and clay matrix in prts, even texture. Top eroded, overlain by aeolian sand; basal contact determined only from cuttings. One core, and cuttings at 3 m intervals from this section, are stored at the BMR Core and Cuttings Laboratory, Fyshwick.|16-MAY-23
28264|Lake Surprise Sandstone|Extent|Poorly exposed over 15 000 km2 in a west northwest trending area extending across the central part of Lander River Sheet area and the northeast part of Mount Solitaire Sheet area.|16-MAY-23
28264|Lake Surprise Sandstone|Thickness range|59 m in type section. Seismic surveys (Kennewell, Mathur and Wilkes, in prep.) suggest very gentle folding and thickening of the Lake Surprise Sandstone to a maximum thickness of approximately 200 m.|16-MAY-23
28264|Lake Surprise Sandstone|Lithology|Sandstone, white, grading to dark brown if ferruginised, very fine to medium grained, well rounded, well sorted, commonly bimodally sorted with silt and clay matrix in parts, silicified and/or ferruginised in some outcrops, generally cross bedded, low angle cross bedding common, slight to extreme slumping in some outcrops.|16-MAY-23
28264|Lake Surprise Sandstone|Relationships and boundaries|Overlain by Cainozoic units. Overlies the Lothari Hill Sandstone, the Point Wakefield Beds, the Hanson River Beds, and crystalline rocks of the Arunta Block. In BMR Lander River 1, the underlying Hanson River Beds are dark red-brown in the 10 m immediately beneath the Lake Surprise Sandstone suggesting that the sandstone was deposited either disconformably or unconformably on a weathered surface. The Lake Surprise Sandstone overlies dolomites of both middle Arenig and late Arenig or early Llanvirian age (E Druce, BMR, pers. comm. 1976), indicating an unconformable basal contact.|16-MAY-23
28264|Lake Surprise Sandstone|Age reasons|No fossils found; overlies the Hanson River Beds, hence it must be post Ordovician (early Llanverian) in age. At latitude 20o34'S, longitude 133o27'E, the Lake Surprise Sandstone is intensely ferruginised, indicating deposition before the development of the laterite soil profile, i.e. before the range late Early Cretaceous to early Miocene.|16-MAY-23
28264|Lake Surprise Sandstone|Comments|Notes: Although mapped previously as Dulcie Sandstone, no conclusive evidence of correlation with this rock unit of the Georgina Basin has been found.       Kennewell P.J., Mather S.P., Wilkes P.G., 1977|16-MAY-23
10163|Langford Gneiss|Name source|After Langford Creek just east of outcrop area; Langford Creek, a tributary of Muller Creek, is in the central-southern part of the  Alcoota 1:250 000 Sheet area, SF53-10, Australian Map Grid.|16-MAY-23
10163|Langford Gneiss|Unit history|Previous informal name: Langford Orthogneiss.|16-MAY-23
10163|Langford Gneiss|Type section locality|Low ridges 11 km west of Mendip Hill at GR 427500E, 48350N, AMG metric.|16-MAY-23
10163|Langford Gneiss|Extent|Between Langford Creek and Plew Bore (GR 4226E, 7485N AMG-metric).|16-MAY-23
10163|Langford Gneiss|Lithology|Porphyroblastic biotite orthogneiss interlayered with minor amounts of schistose biotite-muscovite gneiss; exposed in type area.|16-MAY-23
10163|Langford Gneiss|Relationships and boundaries|Conformable with Mendip Metamorphics. Contact marked by incoming of quartzite of Metamorphics. Intruded by a foliated biotite micro-granite southeast of Plew Bore.|16-MAY-23
10163|Langford Gneiss|Proposed publication|BMR Report|16-MAY-23
10163|Langford Gneiss|Comments|Uniform composition and abundant feldspar porphyroblasts suggest it is a granite, but interpretation is uncertain so term "gneiss" is preferred.|16-MAY-23
10163|Langford Gneiss|Name first published by|Shaw R.D., Warren R.G., Kopras J., Green D.E., 1975|16-MAY-23
41846|Larrie Granodiorite|Name source|Mount Larrie 23o 15' 55" S, 131o 46' 45" E, MOUNT LIEBIG.|16-MAY-23
41846|Larrie Granodiorite|Unit history|Previously included within undifferentiated gneiss, schist, amphibolite, quartzite, granite, dolerite and pegmatite of the Arunta Complex  (Ranford 1969)|16-MAY-23
41846|Larrie Granodiorite|Geomorphic expression|Prominent hills.|16-MAY-23
41846|Larrie Granodiorite|Type section locality|Creek exposure 4 km east-northeast of Mt Larrie, at location 23o15'09.96"S, 131o48'51.57"E (WGS 84), MOUNT LIEBIG.|16-MAY-23
41846|Larrie Granodiorite|Description at type locality|Weakly foliated, medium grained granodiorite with plagioclase phenocrysts 3-5 mm in diameter, and with a mineral assemblage comprising hornblende, biotite, garnet, plagioclase, K-feldspar and quartz.|16-MAY-23
41846|Larrie Granodiorite|Extent|In region of prominent hills 10-20 km west and southwest of Papunya community, MOUNT LIEBIG|16-MAY-23
41846|Larrie Granodiorite|Lithology|Medium grained weakly porphyritic to equigranular foliated granodiorite, with abundant xenoliths of mafic rock. It commonly has small phenocrysts of plagioclase, and has largely recrystallised to a metamorphic assemblage of hornblende, biotite, garnet, plagioclase, K-feldspar and quartz. Igneous clinopyroxene is rarely preserved.|16-MAY-23
41846|Larrie Granodiorite|Relationships and boundaries|Intrudes quartz-bearing mafic rocks of the Papunya Igneous Complex. Contains rafts of quartzite assigned to Yaya Metamorphic Complex. Intrudes felsic gneiss of Yaya Metamorphic Complex. Sharp intrusive relationships with Warumpi Granite, but no unambiguous timing relationships.|16-MAY-23
41846|Larrie Granodiorite|Age reasons|late Palaeoproterozoic (1645-1630 Ma). Forms part of Waluwiya Suite that has SHRIMP U-Pb zircon ages of 1631 +/- 4 Ma (Takyi-Talyi Charnockite) and 1644 +/- 5 Ma (Kakalyi Gneiss) (Kinny 2002, Cross et al in prep).|16-MAY-23
41846|Larrie Granodiorite|Correlations|Strong geochemical affinity with other units of the Waluwiya Suite ? Kakalyi Gniess, Talyi-Talyi Charnockite, Tjungkuba Granodiorite and Russell Charnockite|16-MAY-23
41846|Larrie Granodiorite|Comments|Metamorphosed at upper amphibolite facies conditions during the1590-1560 Ma Chewings Orogeny. Hills of Larrie Granodiorite have distinctive vegetation, with native pines and beantrees on hillslopes.|16-MAY-23
41846|Larrie Granodiorite|References|Cross A, Claoue-Long J, Scrimgeour IR, Close DF & Edgoose CJ, in prep. NTGS-GA Geochronology project, Report 6. Northern Territory Geological Survey, Record **Kinny PD, 2002. SHRIMP U-Pb geochronology of Arunta Province samples from the Mount Liebig and Lake Mackay 1:250 000 mapsheets. Northern Territory Geological Survey, Technical note 2002-015. **Ranford LC, 1969. Mount Liebig, Northern Territory (First Edition). 1:250 000 geological map series explanatory notes, SF52-16. Bureau of Mineral Resources, Australia. **Scrimgeour IR, Close DF & Edgoose CJ, in prep. Mount Liebig, Northern Territory (Second Edition) 1:250 000 geological map series explanatory notes, SE 52-16. Northern Territory Geological Survey, Darwin.|16-MAY-23
22174|Latram Granite|Name source|Latram RIver, east of Cato Plateau, Arnhem Bay- Gove.|16-MAY-23
22174|Latram Granite|Unit history|Outcrop now mapped as this unit was previously mapped as the 'northern area of the Giddy Granite' by Dunnet (1965) and Plumb and Roberts (1992).|16-MAY-23
22174|Latram Granite|Geomorphic expression|The main outcrop area comprises rounded waethered tors and boulders, surrounded by low scrub.|16-MAY-23
22174|Latram Granite|Type section locality|Outcrop centred on lat. 12degrees 15'S, long.136degrees 33'E (AMG PG698454).|16-MAY-23
22174|Latram Granite|Extent|Occupies an area of 10 by 10 km, north of Cato Plateau in Arnhem Bay- Gove, centred on AMG PG698454.|16-MAY-23
22174|Latram Granite|Lithology|Ranges from equigranular, red microgranite to salmon pink, leucocratic, fine- to medium-grained, equigranular, granophyriic calc-alkaline granite. It is massive and lacks xenoliths.|16-MAY-23
22174|Latram Granite|Relationships and boundaries|Intrudes undivided Palaeoproterozoic sandstone. Unconformably overlain by Cretaceous sediments, Cainozoic laterite and Quaternary alluvium.|16-MAY-23
22174|Latram Granite|Age reasons|Palaeoproterozoic (Statherian). The age of this granite, from analysis of single zircon grains by SHRIMP U-Pb geochronological techniques, is 1712+/-10 Ma (Page, pers.comm., 1994). This sample was collected from AMG PG698454.|16-MAY-23
22174|Latram Granite|Correlations|Comagmatic and probably congiguous with the Yanungbi Volcanics. Possible correlative of the Jimbu Granite on the basis of lithological similarities and stratigraphic constraints.|16-MAY-23
22174|Latram Granite|Defn author|T. L. Madigan and D.J. Rawlings, 1997.|16-MAY-23
24355|Laughlen metamorphics|Name source|Mount Laughlen (GR 5751-367152), Laughlen 1:100 000 Sheet area.|16-MAY-23
24355|Laughlen metamorphics|Unit history|Previously mapped by Wells & others (1968) as undivided Arunta Complex.|16-MAY-23
24355|Laughlen metamorphics|Type section locality|Reference area: From 2.2 km southwest of Mount Laughlen (GR 5751-366120) to 7 km south of Mount Laughlen (GR 5751-359143).|16-MAY-23
24355|Laughlen metamorphics|Extent|The unit exteands from directly south of Mount Laughlen westwards to directly south of Cement Dam (I.e. to GR 5751-183121).|16-MAY-23
24355|Laughlen metamorphics|Lithology|Muscovite-biotite schist, thin beds of quartzite, and very rare amphibolite. Additional information on lithology is given in Shaw & others (in preparation).|16-MAY-23
24355|Laughlen metamorphics|Relationships and boundaries|The unit overlies unassigned biotite gneiss (pC) of the southern Ankala Block, and is in faulted contact with the rocks of the Wigley Block.|16-MAY-23
24355|Laughlen metamorphics|Age reasons|Middle Proterozoic or older. Lithologically correlated with the Chewings Range Quartzite, and both units are assigned  to Division 3 of the Arunta Block. The Laughlen metamorphics are therefore inferred to be older than 1700 m.y. and may be older than 1800 m.y.|16-MAY-23
24355|Laughlen metamorphics|Proposed publication|Stewart & others, in prep.|16-MAY-23
24355|Laughlen metamorphics|Comments|Remarks: In addition to the presence of quartzite, the unit is distinguished by the general absence of amphibolite.|16-MAY-23
24355|Laughlen metamorphics|Defn Reference|80/20787|16-MAY-23
24355|Laughlen metamorphics|Proposer|Shaw R.D. (in Shaw & others, in preparation)|16-MAY-23
75721|Leaky Norite|Name source|After Leaky Bore, GDA94 53K 525650mE 7405750mN (-23°27'29"S 135°15'4"E)|16-MAY-23
75721|Leaky Norite|Unit history|Previously unnamed (but mapped) norite and gabbro intrusions|16-MAY-23
75721|Leaky Norite|Geomorphic expression|Forms conspicuous, dark-coloured and poorly vegetated hills|16-MAY-23
75721|Leaky Norite|Type section locality|Mount Emma, GDA94 53K 524700mE 7421800mN ( 23°18'47"S  135°14'30"E)|16-MAY-23
75721|Leaky Norite|Description at type locality|Coarse-grained, layered olivine-norite and olivine-gabbronorite.|16-MAY-23
75721|Leaky Norite|Extent|Comprises four main plutons in the Quartz 1:100 000 mapsheet (5951), Northern Territory: (1) 2 km from Leaky Bore at GDA94 53K 525500mE 7408500mN (-23°25'60"S  135°14'59"E); (2) at Mount Emma GDA94 53K 523642nE 7423371mN (-23°17'56"S  135°13'52"E); (3) three small outcrops ca 1 km east of Huckitta Bore at GDA94 53K 533752mE 7440729mN ( 23°8'31"S  135°19'47"E) ca 1 km southeast of Huckitta Bore at GDA94 53K 533800mE 7439800mN (-23°9'1"S  135°19'49"E)  and ca 1 km northeast of Huckitta Bore at 533400mE 7441200mN ( 23°8'16"S   135°19'34"E) and a large outcrop 2 km northeast of Huckitta Bore at GDA94 53K 534000mE 7442400mN (-23°7'37"S  135°19'55"E); and (4) 2 km east of Salthole Dam at GDA94 53K 516000mE 7422000mN (-23°18'41"S  135°9'23"E). May also include a number of other scattered discordant [eg at GDA94 53K 531500mE 7432000mN (-23°13'15"S 135°18'28"E)] and stratiform  meta-mafic/ultramafic rocks in the Entia Gneiss Complex.|16-MAY-23
75721|Leaky Norite|Lithology|Olivine norite and olivine gabbronorite, troctolite and gabbro with ophitic, corona (olivine mantled by orthopyroxene) and symplectic textures (hornblende-spinel partially overprinting clinopyroxene-spinel, and orthopyroxene-spinel).|16-MAY-23
75721|Leaky Norite|Depositional environment|Genesis: Primary mantle melt and fractionated differentiates|16-MAY-23
75721|Leaky Norite|Relationships and boundaries|There is typically a sheared contact between the ca 1750 Ma (see further below) Bruna Gneiss (granitic orthogneiss) and the Leaky Norite. Bruna Gneiss locally intrudes the Mount Emma pluton of the Leaky Norite (eg GDA94 53K 523642mE 7423371mN; -23°17'56"S 135°13'52"E) where mingling between granite and norite are also locally evident. Well-developed and exposed mingling between the Bruna Gneiss (or age-equivalent (1750 ± 5 Ma, Hollis et al 2010) unnamed hypersthene-bearing phase of the orthogneiss in the Huckitta Bore boudin) and the Leaky and Huckitta bore plutons of the Leaky Norite are seen at, for example, GDA94 53K 525456mE 7409415mN (-23°25'30"S 135°14'57"E) and GDA94 53K 533752mE 7440729mN (-23°8'31"S 135°19'47"E), respectively.|16-MAY-23
75721|Leaky Norite|Identifying features|This small group of outcropping norite/gabbronorite plutons are identified by their magma mingling relationships with the granitic Bruna Gneiss.|16-MAY-23
75721|Leaky Norite|Structure and Metamorphism|Locally cross-cut by shear zones and dolerite dykes with a probable igneous crystallisation age of 1728 +/- 6 Ma (Whelan et al in prep). Corona and symplectic textures in the Leaky Norite probably relate to igneous crystallisation at moderate pressures (ca 8 kbar) during the Strangways Metamorphic Event rather than post-crystallisation metamorphism (Donnellan in prep, Foden et al 1995). There is overprinting metamorphism adjacent to shear zones, eg in the Salthole Dam intrusion at GDA94 53K 515461mE 7421725mN (-23°18'50"S 135°9'4"E), and strongly deformed garnet-amphibolite adjacent to the Huckitta Bore intrusion (Foden et al, 1995). Joklik (1955) recognised that apparent chilling near the margin of the Mount Emma pluton in fact resulted from local metamorphic recrystallisation to  a fine-grained granoblastic textured rock.|16-MAY-23
75721|Leaky Norite|Age reasons|The age of the unit is constrained by magma mingling with the Bruna Gneiss. This gneiss has a conventional U-Pb igneous crystallisation age of 1748 +5/-4 Ma (Mortimer et al 1987) and 1745 +7/-9 Ma (Cooper et al 1988). These ages are corroborated by recent laser ablation age determinations (see Hollis et al 2010). The age of the Leaky Norite is also constrained by a 1780 +/- 116 Ma Sm-Nd whole-rock model 1 isochron for gabbros from the Huckitta Bore pluton (Foden et al 1995).|16-MAY-23
75721|Leaky Norite|Alteration and Mineralisation| Locally altered/metamorphosed adjacent to cross-cutting or bounding shear zones, eg GDA94 53K 515461mE 7421725mN (-23°18'50"S 135°9'4"E). Amphibolites in the Entia Dome that probably relate to the Leaky Norite include orthoamphibole-bearing types that are interpreted to reflect alteration (Arnold et al, 1995).|16-MAY-23
75721|Leaky Norite|Geophysical Expression|Forms conspicuous, dark-coloured and poorly vegetated hills|16-MAY-23
75721|Leaky Norite|Geochemistry|High-magnesian parental (primary, tending to picritic) tholeiitic magma,, and fractionation and cumulate products.|16-MAY-23
75721|Leaky Norite|Defn author|Donnellan, N. (NTGS),  03-NOV-2010|16-MAY-23
75721|Leaky Norite|Comments|Foden et al (1995) concluded that the Huckitta Bore intrusion was bimodal and, in addition to mafic rocks (Leaky Norite), comprised a charnockite-mangerite series (which includes the Bruna Gneiss). This represents the extreme magmatic differentiation products of the tholeiitic mafic rocks.|16-MAY-23
75721|Leaky Norite|References|**ARNOLD J, Sandiford M and Wetherley S, 1995. Metamorphic events in the eastern Arunta Inlier, Part 1. Metamorphic petrology. Precambrian Research 71, 183-205.    **DONNELLAN N, in prep. Mafic rocks of the eastern Aileron Province in Illogwa Creek and Alice Springs 1:250 000 map sheets. Northern Territory Geological Survey, Report.     **FODEN J, Mawby J, Kelley S, Turner S and Bruce D, 1995. Metamorphic events in the eastern Arunta Inlier, Part 2. Nd-Sr-Ar isotopic constraints. Precambrian Research 71, 207-227.    **JOKLIK GF, 1955. The geology and mica-fields of the Harts Range, central Australia. Bureau of Mineral Resources, Geology and Geophysics, Bulletin 26.    **COOPER JA, Mortimer GE and James PR, 1988. Rate of Arunta Inlier evolution at the eastern margin of the Entia Dome, central Australia. Precambrian Research 40/41, 217-231.    **HOLLIS JA, Beyer E, Whelan JA, Kemp AIS, Scherstén A and Greig A, 2010. Summary of results. NTGS laser U-Pb and Hf geochronology project: Pine Creek Orogen, Murphy Inlier, McArthur Basin and Arunta Region, July 2007-June 2008. Northern Territory Geological Survey, Record 2010-001.    **MORTIMER GE, Cooper JA and James PR, 1987. U-Pb and and R-Sr geochronology and geological evolution of the Harts Range ruby mine area of the Arunta Inlier, central Australia. Lithos 20, 445-467.    **WHELAN JA, Hallett L and Close DF, in prep. Quartz, Northern Territory. 1:100 000 Geological Map Series Explanatory Notes, 5951. Northern Territory Geological Survey, Darwin.|16-MAY-23
10289|Ledan Schist|Name source|After Ledan Peak, 'Utopia' Station, northeastern Alcoota 1:250 000 Sheet area, SF53-10, Australian map Grid.|16-MAY-23
10289|Ledan Schist|Unit history|Ledan Schists.|16-MAY-23
10289|Ledan Schist|Type section locality|In unnamed range across syncline centred at 4710E 75183N AMG (metric) 11 km west of 'Delmore Downs' homestead. Includes boundaries with Utopia Quartzite and Delmore Metamorphics.|16-MAY-23
10289|Ledan Schist|Extent|From Ledan Peak east to beyond Sheet border.|16-MAY-23
10289|Ledan Schist|Lithology|Muscovite-quartz schist, muscovite-biotite-quartz schist, tourmaline-quartzite, minor para-amphibolite, metamorphosed ?chert, granule conglomerate, boulder beds and conglomerate. All exposed in type section.|16-MAY-23
10289|Ledan Schist|Relationships and boundaries|Unconformably overlies the Delmore Metamorphics. Contains a basal conglomeratic unit; minor units of the Delmore Metamorphics being truncated by the unconformity. May unconformably overlie Delny gneiss, but contact is not exposed. Granite south of Lily Bone intrudes the Ledan Schist. The granite foliation parallels the axial-plane schistosity in the Ledan Schist suggesting that folding was synchronous with granite intrusion.|16-MAY-23
10289|Ledan Schist|Correlations|Tentative correlations: Grouped with the Utopia Quartzite as equivalents of the Hatches Creek Group and the Reynolds Range Group, in which case it may be Early Proterozoic in age. A K/Ar date of 1532 m.y. was obtained on muscovite from the Ledan Schist and 1537 m.y. was obtained on a pegmatite that intrudes the Ledan Schist. The dates are minima and are considered to be somewhat reset.|16-MAY-23
10289|Ledan Schist|Proposed publication|BMR Report|16-MAY-23
10289|Ledan Schist|Name first published by|Shaw R.D., Warren R.G., Kopras J., Green D.E., 1975|16-MAY-23
24357|Lennee Creek Formation|Name source|Lennee Creek, which joins the Frew River at GR 180180, Hatches 1:100 0000 Sheet area, Frew River 1:250 000 Sheet area.|16-MAY-23
24357|Lennee Creek Formation|Type section locality|In centre of syncline in W part of Elkedra 1:100 000 Sheet area (Elkedra 1:250 000 Sheet area), 40 km west of Elkedra homestead (latitude 21o11'00"S, longitude 135o28'00"E). Here, the formation dips steeply N, overlies the Alinjabon Sandstone and is partly overlain unconformably by flat-lying Cambrian conglomerate. It is about 1500 m thick, and consists of thinly bedded and partly cleaved siltstone, shale, and friable arenite.|16-MAY-23
24357|Lennee Creek Formation|Extent|Throughout Davenport Province, i.e., E and central parts of Bonney Well, SW part of Frew River, NW part of Elkedra, NE part of Barrow Creek 1:250 000 Sheet areas.|16-MAY-23
24357|Lennee Creek Formation|Thickness range|Generally about 1000 m; maximum about 1500 m, as in type section.|16-MAY-23
24357|Lennee Creek Formation|Lithology|Recessive siltstone, shale, and friable feldspathic/lithic/kaolinic/sericitic arenite; minor thin ridge-forming quartz arenite bands and calcareous beds.|16-MAY-23
24357|Lennee Creek Formation|Relationships and boundaries|Conformably overlies ridge-forming Alinjabon Sandstone, conformably overlain by ridge-forming Canulgerra Sandstone. Base taken at base of recessive beds - shale, siltstone, or fine lithic arenite - overlying ridge-forming arenite at top of Alinjabon Sandstone. Top generally concealed. Overlain unconformably by Cambrian strata.|16-MAY-23
24357|Lennee Creek Formation|Age reasons|Younger than 1870 Ma (U-Pb zircon date on volcanics in the Warramunga Group, which is unconformably overlain by the Hatches Creek Group), and older than 1640 Ma (Rb-Sr whole-rock approximate date on granite intruding the Hatches Creek Group).|16-MAY-23
24357|Lennee Creek Formation|Comments|Remarks: Part of the Hanlon Subgroup of the Hatches Creek Group. Distinctive recessive unit of mostly lutite, overlain and underlain by units of resistant arenite.|16-MAY-23
24357|Lennee Creek Formation|Defn Reference|86/25362|16-MAY-23
24357|Lennee Creek Formation|Proposer|Stewart A.J.|16-MAY-23
24357|Lennee Creek Formation|Resdate|07-OCT-1981|16-MAY-23
79225|Liddle Formation|Name source|Liddle Hills (extending east and west of 132.2778deg E,  -24.8972deg S) in southwestern HENBURY 1:250 000 mapsheet.|16-MAY-23
79225|Liddle Formation|Unit history|Formerly mapped as part of Winnall beds of Ranford et al (1965); may in part be synonymous with unit 2 of Winnall beds at Winnall Ridge in LAKE AMADEUS 1:250 000 mapsheet (GDA94 53K 734373mE 7258954mN) (see Ranford and Cook 1964).|16-MAY-23
79225|Liddle Formation|Constituents|Locally divided into three informal lithofacies [lower (A), middle (B) and upper (C)] on basis of bedding and corresponding outcrop characteristics, and sedimentary structures.|16-MAY-23
79225|Liddle Formation|Geomorphic expression|Predominantly ridge-forming, with subordinate, generally recessive, thinly bedded sandstone at top.|16-MAY-23
79225|Liddle Formation|Type section locality|Northern flank of Liddle Hills at approximately GDA94 53J 226979mE 7244371mN extending up-section to GA94 53J 227158mE 7243020mN, where unit is approximately 650 m thick on northern limb of westerly-trending syncline.  Reference localities: Transitional lower contact with Froud Formation is well exposed near GDA94 53J 286349mE 7276939mN in hills south of Dead Bullock Plain; transitional upper contact with Puna Kura Kura Formation is exposed near GDA94 53J 227131mE 7243107mN in Liddle Hills further to west of type locality/section.|16-MAY-23
79225|Liddle Formation|Extent|Currently mapped in central and southwestern HENBURY 1:250 000 mapsheet. Regional extent not yet known, but formation probably extends into LAKE AMADEUS and BLOODS RANGE 1:250 000 mapsheets.|16-MAY-23
79225|Liddle Formation|Thickness range|Approximately 650 m in type section.Variations currently unknown.|16-MAY-23
79225|Liddle Formation|Lithology|Sandstone: feldspathic, subarkosic, arkosic and minor quartzic sandstone at the type locality, indicating variable maturity. All sandstone compositions are iron oxide-bearing although iron oxide content is less in more mature, less feldspar-rich sandstone. Quartz component is typically well-sorted and well-rounded in all sandstones. Elsewhere, particularly where unit is thin, quartz arenite predominates. Lower lithofacies (A) is cyclical with thinly planar-parallel-bedded sandstone overlain by medium- to thickly-bedded, low-angle cross-bedded sandstone; middle lithofacies (B) is bi-directionally cross-bedded; upper lithofacies (C) is an `event¿ facies comprising small-scale trough and festoon cross-bedded sandstone with abundant ripple marks and weathered-out shale clasts; ripple marks are locally abundant. These three lithofacies are well-represented in type section and more generally in Liddle Hills. Locally elsewhere, eg in hills south of Dead Bullock Plain (around GDA94 53J 285973mE 7276891mN) lower facies (A) apparently predominates and comprises cyclically interlayered thinly-bedded and internally laminated, medium to thickly-bedded quartz-rich sandstone. Absence of lithofacies B and C in this area may be from lack of exposure, but is more likely due to erosion or non-deposition.|16-MAY-23
79225|Liddle Formation|Depositional environment|Shallow marine / intertidal.|16-MAY-23
79225|Liddle Formation|Fossils|None known.|16-MAY-23
79225|Liddle Formation|Relationships and boundaries|Transitional contacts with the underlying Froud Formation and overlying Puna Kurra Kurra Formation respectively. Froud Formation becomes increasingly fine-grained, more well-sorted and well-rounded quartz arenite transitional to Liddle Formation. The contact is marked by the in-coming of medium-bedded, coarse-grained, moderately well-sorted and rounded quartz arenites that are locally associated with a topographic 'bench' at the base of Liddle Formation. Recessive, fine-grained, very-thinly- to thinly-planar-parellel bedded, internally laminated sandstone overlies the ridge-forming interval of Liddle Formation. These thinly-bedded sandstones may be transitional to the Puna Kura Kura Formation but are included in Liddle Formation. The base of the overlying Puna Kura Kura Formation is taken as the onset of the next ridge-forming sandstone.|16-MAY-23
79225|Liddle Formation|Identifying features|The cyclical character of lower Liddle Formation distinguishes it from underlying units. Thin-bedding associated with abundant small-scale sedimentary structures distinguish upper Liddle Formation, although ripple-marked sandstone with weathered-out shale clasts occurs locally at the base of the overlying Puna Kura Kura Formation consistent with its probable transitional relationship with Liddle Formation.|16-MAY-23
79225|Liddle Formation|Structure and Metamorphism|Folded and faulted, but apparently unmetamorphosed.|16-MAY-23
79225|Liddle Formation|Age reasons|Its stratigraphic position and relationships indicate that it may in part correlate with Pertatataka Formation which has an Ediacaran-aged palynoflora (Grey 2005). Liddle Formation may therefore be late Ediacaran and/or early Cambrian in age.|16-MAY-23
79225|Liddle Formation|Correlations|Parent Winnall Group (former Winnall beds) was correlated with Pertatataka Formation by Ranford and Cook (1964), but the stratigraphic succession and age of the latter formation were substantially revised by Wells et al (1967) and Priess et al (1978). It is likely that Winnall Group only in part correlates with revised Pertatataka Formation (Donnellan and Normington 2017).|16-MAY-23
79225|Liddle Formation|Geophysical Expression|Generally linear, low Total Magnetic Intensity as is typical of Winnall Group.|16-MAY-23
79225|Liddle Formation|Defn author|N Donnellan, VJ Normington, 26-FEB-2017.|16-MAY-23
79225|Liddle Formation|References|Donnellan N and Normington VJ, 2017. Towards a stratigraphy for the Neoproterozoic and probable early Cambrian in the central Amadeus Basin, Northern Territory: in Annual Geoscience Exploration Seminar (AGES) Proceedings, Alice Springs, Northern Territory 28¿29 March 2017. Northern Territory Geological Survey, Darwin. ***Grey K, 2005. Ediacaran palynology of Australia. Australian Association of Australasian Palaeontologists, Memoir 31, 1¿439. ***Priess WV, Walter MR, Coats RP and Wells AT, 1978. Lithological correlations of Adelaidean glaciogenic rocks in parts of the Amadeus, Ngalia and Georgina Basins. BMR Journal of Australian Geology and Geophysics 3, 45¿53. ***Ranford LC and Cook PJ, 1964. The geology of the Henbury 1:250 000 sheet area, Amadeus Basin, Northern Territory. Bureau of Mineral Resources, Australia, Record 1964/40. ***Ranford LC, Cook PJ and Wells AT, 1965. The geology of the central part of the Amadeus Basin, Northern Territory. Bureau of Mineral Resources, Australia, Report 86. ***Wells AT, Ranford, LC, Stewart AJ, Cook PJ and Shaw RD, 1967. Geology of the north-eastern part of the Amadeus Basin, Northern Territory. Bureau of Mineral Resources, Australia, Report 113.|16-MAY-23
75948|Lilyarba Mafics|Name source|After Lilyarba Creek, GDA 94 52L 715900mE 8419700mN (14°17'10"S 131°00'5"E) Fergusson River 1:250 000 mapsheet, Wingate Mountains 1:100 000 mapsheet, Litchfield Province, Pine Creek Orogen, Northern Territory.|16-MAY-23
75948|Lilyarba Mafics|Unit history|Previously known as Wangi Basics, first used by Needham and Stuart-Smith (1984) and formally defined in Dundas et al (1987). The name Wangi Basics is abandoned, as it is now known to comprise distinct geochemical groups which are genetically unrelated.|16-MAY-23
75948|Lilyarba Mafics|Geomorphic expression|Boulder-strewn hummocky rises (Edgoose et al 1989).|16-MAY-23
75948|Lilyarba Mafics|Type section locality|Large exposure in Fergusson River 1:250 000, central Wingate Mountains 1:100 000 mapsheets, 60 km south of Daly River township. GDA94 52L 693500mE 8417500mN (14°18'28"S 130°47'38"E).|16-MAY-23
75948|Lilyarba Mafics|Description at type locality|Exposed in boulder-strewn hummocky rises (Edgoose et al 1989)|16-MAY-23
75948|Lilyarba Mafics|Extent|Mafic rocks in this area are exposed over an area of 8 km2. First vertical derivative magnetic image does not indicate greater subsurface extent.|16-MAY-23
75948|Lilyarba Mafics|General description|Slightly altered, lower-amphibolite-facies probable lamprophyre; includes minor shoshonitic cumulate. Rocks are characteristically low-SiO2 with no free quartz|16-MAY-23
75948|Lilyarba Mafics|Lithology|Possible altered lamprophyre; mineralogy dominated by sericitised plagioclase (labrodorite, andesine) and hornblende, and minor biotite and opaque minerals (Edgoose et al 1989).|16-MAY-23
75948|Lilyarba Mafics|Depositional environment|Genesis: Intrusive|16-MAY-23
75948|Lilyarba Mafics|Relationships and boundaries|Intrudes Burrell Creek Formation and intruded by Soldiers Creek Granite as inferred by Edgoose et al (1989).|16-MAY-23
75948|Lilyarba Mafics|Identifying features|Comprises fine-grained, altered low-grade metamorphic rocks with distinctive strong alkaline geochemical signatures. Age of 1830 Ma distinguishes these rocks from other former Wangi Basics constituents, which must be in range 1860-1855 Ma based on stratigraphic relationships.|16-MAY-23
75948|Lilyarba Mafics|Structure and Metamorphism|Lower amphibolite-facies metamorphism. Structural relationships unknown.|16-MAY-23
75948|Lilyarba Mafics|Age reasons|Worden et al (2008) reported a 207Pb/206Pb SHRIMP zircon age of 1829 +/-4 Ma [from a sample of  Wangi Basics described as "a stock-like intrusion in central Wingate Mountains... a fine-medium grained quartz-bearing diorite"].|16-MAY-23
75948|Lilyarba Mafics|Correlations|Correlative of olivine-mica-K-feldspar lamprophyre dykes at Mount Bundey, Central Domain, Pine Creek Orogen, Northern Territory (Sheppard and Taylor 1992).|16-MAY-23
75948|Lilyarba Mafics|Alteration and Mineralisation|Sericitic alteration of plagioclase feldspar; some alteration of hornblende to actinolite and tremolite; partial chloritisation of biotite. No known mineralisation.|16-MAY-23
75948|Lilyarba Mafics|Geophysical Expression|Positive magnetic response.|16-MAY-23
75948|Lilyarba Mafics|Geochemistry|Mafic rocks with distinctive potassic signatures; silica values typically low (<50 wt% SiO2), alumina high (20 wt% Al2O3).|16-MAY-23
75948|Lilyarba Mafics|References|DUNDAS DL, Edgoose CJ, Fahey GM and Fahey JE, 1987. Daly River 1:100 000 Geological Map Series. Northern Territory Geological Survey Explanatory Notes (5070).  **EDGOOSE CJ, Fahey GM and Fahey JE, 1989. Wingate Mountains 1:100 000 Geological Map Series. Northern Territory Geological Survey Explanatory Notes (5069).  **GLASS LM, 2010. Palaeoproterozoic island-arc-related rocks of the Litchfield Province, western Pine Creek Orogen, Northern Territory. Northern Territory Geological Survey, Record 2010-005.  **NEEDHAM RS, Stuart-Smith PG, 1984. Geology of the Pine Creek Geosyncline, Northern Territory, 1:500 000 scale map. Bureau of Mineral Resources, Australia, Canberra.  **SHEPPARD S and Taylor WR, 1992. Barium- and LREE-rich olivine-mica-lamprophyres with affinities to lamproites, Mt. Bundey, Northern Territory, Australia: in Foley S and Peccerillo A (editors) 'Potassic and ultrapotassic magmas and their origin; Sixth meeting of the European Union of Geosciences (EUG VI)'. Lithos 28, (3-6), 303-325.  **WORDEN KE, Carson CJ, Close DF, Donnellan N and Scrimgeour IR, 2008. Summary of results. Joint NTGS-GA geochronology, Tanami Region, Arunta Region, Pine Creek Orogen and Halls Creek Orogen correlatives, January 2005-March 2007. Northern Territory Geological Survey Record 2008-3.|16-MAY-23
22206|Littlers Pegmatite|Name source|Littlers Yard GR 306200 7385800 MacDonnell Ranges 1:100 000 Sheet area.|16-MAY-23
22206|Littlers Pegmatite|Geomorphic expression|Light-coloured ridges.|16-MAY-23
22206|Littlers Pegmatite|Type section locality|3 km southeast of Littlers Yard GR 307500 7383800, MacDonnell Ranges 1:100 000 Sheet area.|16-MAY-23
22206|Littlers Pegmatite|Extent|South of the Redbank Thrust Zone, north of the Chewings Range, extending west from near Old Hamilton Downs homestead to north of Fish Hole on Ellery Creek.|16-MAY-23
22206|Littlers Pegmatite|Lithology|Coarse-grained muscovite-bearing pegmatite.|16-MAY-23
22206|Littlers Pegmatite|Relationships and boundaries|Cut by narrow mylonite zones of Alice Springs age, crosscut by Stuart dykes, spatially independent of deformed zones of Chewings deformation, transgress all units affected by Chewings deformation.|16-MAY-23
22206|Littlers Pegmatite|Structure and Metamorphism|Near-vertical dykes, arranged en echelon to Chewings High-strain Zones.|16-MAY-23
22206|Littlers Pegmatite|Age reasons|Possibly 1140 Ma (Shaw & Black, 1992, age of similar pegmatite near Redbank Hill).|16-MAY-23
22206|Littlers Pegmatite|Defn author|R.D. Shaw, 1991.|16-MAY-23
22206|Littlers Pegmatite|Comments|This 'definition' is missing the details of references mentioned in the age, and shows no signs on the card of having been approved.|16-MAY-23
31284|Liverpool Breccia|Name source|Liverpool Crater (lat. 12 deg 24'S, long. 134 deg 03'E), northern Arnhem Land|16-MAY-23
31284|Liverpool Breccia|Unit history|Rix (1965) mapped the unit as part of the Kombolgie Formation.|16-MAY-23
31284|Liverpool Breccia|Geomorphic expression|Circular ridge 1.6 km in diameter.|16-MAY-23
31284|Liverpool Breccia|Type section locality|SE exterior side of ring, from base to top of ridge (lat. 12 deg.  23'58"'S, long. 134 deg. 03'10"E, GR 397000 8629050).|16-MAY-23
31284|Liverpool Breccia|Extent|Exposed around the rim of the Liverpool impact crater.|16-MAY-23
31284|Liverpool Breccia|Thickness range|About 50 m (Guppy et al., 1971).|16-MAY-23
31284|Liverpool Breccia|Lithology|Breccia of sandstone blocks derived from the underlying sandstone of the Kombolgie Subgroup.  The clasts range in size from a few millimetres to 7 m, and are mostly angular and roughly equant, although some are elongate.|16-MAY-23
31284|Liverpool Breccia|Depositional environment|The breccia was produced by bolide impact.|16-MAY-23
31284|Liverpool Breccia|Relationships and boundaries|Unconformably overlies Kombolgie Subgroup sandstone, with an irregular contact having several metres of relief.  Undeformed sandstone in outcrops in the centre of the ring, interpreted as Cretaceous in age (Guppy et al., 1971), has no exposed contact with the unit, but would overlie it on the presumption that the breccia extends in the subsurface to cover the initial floor of the structure.|16-MAY-23
31284|Liverpool Breccia|Identifying features|The breccia lithology, and its distribution in a circular ridge, are unique in the region.|16-MAY-23
31284|Liverpool Breccia|Structure and Metamorphism|Usually unbedded.  Where crude bedding is visible, it lies within a few degrees of horizontal.|16-MAY-23
31284|Liverpool Breccia|Age reasons|The age is between that of the Palaeoproterozoic Kombolgie Subgroup and the interpreted Cretaceous sandstone in the centre of the crater (Guppy et al., 1971).  The well-preserved rim suggests that it was buried before much erosion could take place, so formation of the structure in the Cretaceous is likely.|16-MAY-23
31284|Liverpool Breccia|References|GUPPY, D.J., Brett, R., & Milton, D.J., 1971 - Liverpool and Strangways Craters,Northern Territory: two structures of probable impact origin.  Journal of Geophysical Research, 76, 5387-5393.   RIX, P., 1965 - 1:250,000 Geological Series Explanatory Notes: Milingimbi, N.T., Sheet SD/53-2.  Bureau of Mineral Resources, Australia.|16-MAY-23
41847|Lizard Schist|Name source|Lizard Bore  23o 18' 20" S, 131o 07' 40" E, MOUNT LIEBIG.|16-MAY-23
41847|Lizard Schist|Unit history|Previously included within undifferentiated gneiss, schist, amphibolite, quartzite, granite, dolerite and pegmatite of the Arunta Complex  (Ranford 1969)|16-MAY-23
41847|Lizard Schist|Geomorphic expression|Low rounded isolated hills and in talus slopes beneath ridges of Heavitree Quartzite|16-MAY-23
41847|Lizard Schist|Type section locality|Hill 8 km south-southwest of Mount Liebig community, at location 23o20'08.10"S, 131o14'27.18E (WGS 84), MOUNT LIEBIG.|16-MAY-23
41847|Lizard Schist|Description at type locality|Muscovite-biotite-quartz schist interlayered with quartz-muscovite metapsammite with narrow quartzite layers.|16-MAY-23
41847|Lizard Schist|Extent|In low hills around headwaters of Warren Creek and Berry Pass Creek, 5-10 km south of Mount Liebig community, MOUNT LIEBIG.|16-MAY-23
41847|Lizard Schist|Lithology|Muscovite-biotite-quartz schist interlayered with quartz-muscovite metapsammite, with varying degrees of tourmalinisation. Rare quartzite and garnet-bearing schist.|16-MAY-23
41847|Lizard Schist|Relationships and boundaries|Has ambiguous highly strained intrusive or tectonic contact with Talipata Granite. Intruded by pegmatites with associated tourmalinisation. Faulted contact with Peculiar Complex. Unconformably overlain by Heavitree Quartzite.|16-MAY-23
41847|Lizard Schist|Age reasons|late Palaeoproterozoic (1650-1600 Ma).  SHRIMP U-Pb dating of detrital zircons from a quartz-rich psammite layer at the type locality a youngest zircon analysis with an apparent age 1642 +/- 40 Ma . An alternative maximum age constraint of 1657 +/- 28 Ma can be calculated from the youngest six analyses (Cross  et al in prep). The unit is believed to have been metamorphosed during the 1590-1560 Ma Chewings Orogeny.|16-MAY-23
41847|Lizard Schist|Correlations|Correlated with Ikuntji Metamorphics. Has broad lithological similarities with metasedimentary units of the Iwupataka Metamorphic Complex in HERMANNSBURG.|16-MAY-23
41847|Lizard Schist|Comments|Metamorphosed at lower to middle amphibolite facies during 1590-1560 Ma Chewings Orogeny.|16-MAY-23
41847|Lizard Schist|References|Cross A, Claoue-Long J, Scrimgeour IR, Close DF & Edgoose CJ, in prep. NTGS-GA Geochronology project, Report 6. Northern Territory Geological Survey, Record  **Ranford LC, 1969. Mount Liebig, Northern Territory (First Edition). 1:250 000 geological map series explanatory notes, SF52-16. Bureau of Mineral Resources, Australia. **Scrimgeour IR, Close DF & Edgoose CJ, in prep. Mount Liebig, Northern Territory (Second Edition) 1:250 000 geological map series explanatory notes, SE 52-16. Northern Territory Geological Survey, Darwin. **Stewart AJ, Shaw RD, Offe LA, Langworthy AP, Warren RG, Allen AR & Clarke DB, 1980. Stratigraphic definitions of named units in the Arunta Block, Northern Territory. Bureau of Mineral Resources, Australia, Report 216.|16-MAY-23
77878|Lloyd Gabbronorite|Name source|After Mt Lloyd, GDA94 53K 547654mE 7417659mN  (-23°34'9"S, 135°46'6"E)|16-MAY-23
77878|Lloyd Gabbronorite|Unit history|Previously unnamed (but mapped) gabbronorite and gabbro intrusions.|16-MAY-23
77878|Lloyd Gabbronorite|Geomorphic expression|Forms small, dark, poorly vegetated hillocks and mounds.|16-MAY-23
77878|Lloyd Gabbronorite|Type section locality|Small intrusive body forming a hillock, north of the Indiana Homestead, in the Irindina Province on ILLOGWA CREEK 1:250 000 mapsheet, QUARTZ 1:100 000 mapsheet. GDA94 53K 545412mE 7424501mN (-23º17'17"S, 135º26'38"E).|16-MAY-23
77878|Lloyd Gabbronorite|Description at type locality|Small hill exposure of medium- to coarse-grained olivine gabbro norite and olivine gabbro preserving primary igneous textures. In places has a characteristic pitted appearance attributed to the weathering out of olivine.|16-MAY-23
77878|Lloyd Gabbronorite|Extent|Rare plutons and small intrusions in the vicinity of the Indiana Homstead (location) and extending along strike to the northwest towards Mt Mary.|16-MAY-23
77878|Lloyd Gabbronorite|Lithology|Medium- to coarse-grained olivine gabbro norite and olivine gabbro.|16-MAY-23
77878|Lloyd Gabbronorite|Depositional environment|/Genesis: Crustally contaminated primary mantle melt.|16-MAY-23
77878|Lloyd Gabbronorite|Relationships and boundaries|There is generally a high-strain contact between the gabbronorite and gabbro plutons and the Yambla Gneiss which they intrude. The plutons of the Lloyd Gabbronorite are relatively undeformed and unmetamorphosed compared to the upper-amphibolite- to granulite-facies metapelites and metapsammites of the Yambla Gneiss which are characterised by a well-developed high-strain transposition fabric.|16-MAY-23
77878|Lloyd Gabbronorite|Identifying features|This small group of gabbronorite and gabbro plutons are identified by its relatively undeformed and unmetamorphosed nature. The plutons are distinguished from the mineralogically and texturally similar Leaky Norite (Whelan et al in prep) on the basis of trace element geochemistry and that they are not temporally or spatially associated with the Bruna Granitic Gneiss.|16-MAY-23
77878|Lloyd Gabbronorite|Structure and Metamorphism|The unit is relatively undeformed and unmetamorphosed.|16-MAY-23
77878|Lloyd Gabbronorite|Age reasons|The age of this unit is constrained by the lack of evidence for metamorphism during the 480-460 Ma Larapinta Event (Mawby et al. 1999). The age of the Lloyd Gabbronorite is also constrained by a zircon SHRIMP U-Pb concordia age of 411 ± 5 Ma (Hollis et al. in press.).|16-MAY-23
77878|Lloyd Gabbronorite|Alteration and Mineralisation|The Lloyd Gabbronorite hosts magmatic Ni-Cu sulfides (pentlandite and chalcopyrite). Mithril Resources Ltd defined the Blackadder and Baldrick Ni-Cu +/- PGE prospects. Initial rock chip samples at Blackadder assayed up to 3.8% Ni and 9.6% Cu, with anomalous cobalt, platinum and palladium (Mithril Resources Ltd, ASX Announcement, 15 September 2008). These were subsequently drilled with a best intersection of 9m @ 0.48% Ni and 0.3% Cu from Baldrick (Mithril Resources Ltd, ASX Announcement, 30 October 2009).|16-MAY-23
77878|Lloyd Gabbronorite|Geophysical Expression|Reversely magnetically polarised.|16-MAY-23
77878|Lloyd Gabbronorite|Geochemistry|High-magnesian, crustally contaminated, tholeiitic magma.|16-MAY-23
77878|Lloyd Gabbronorite|Defn author|JA Whelan|16-MAY-23
77878|Lloyd Gabbronorite|Proposed publication|Whelan JA, Hallett L and Close DF, in prep. QUARTZ, Northern Territory. 1:100 000 Geological Map Series Explanatory Notes, 5951. Northern Territory Geological Survey, Darwin.|16-MAY-23
77878|Lloyd Gabbronorite|References|Hollis JA, Beyer EE, Whelan JA, Glass LM, Yaxley G, Armstrong R, Allen C and Rosenthal A, in prep. Summary of results. NTGS laser and SHRIMP U-Pb, Hf and O geochronology project: Pine Creek Orogen and Arunta Region, July 2008¿December 2010.***Mawby J, Hand M and Foden J, 1999. Sm-Nd evidence for Ordovician granulite facies metamorphism in an intraplate setting in the Arunta Inlier, central Australia. Journal of Metamorphic Geology 17, 653-668.|16-MAY-23
10668|Lothari Hill Sandstone|Name source|Lothari Hill; latitude 18o50'12"S, longitude 131o29'6"E, Winnecke Creek 1:250 000 Sheet SE 52-12.|16-MAY-23
10668|Lothari Hill Sandstone|Unit history|Included in Chewings' (1931) Winnecke Creek Tableland Formation. Milligan, Smith, Nichols and Doutch (1966) included this rock unit in the Merrina Beds.|16-MAY-23
10668|Lothari Hill Sandstone|Type section locality|In stratigraphic drill hole BMR Green Swamp Well 4, latitude 19o16'S, longitude 132o39'E, from the surface to a depth of 94 metres (Kennewell & Huleatt, in prep.). One core, and cuttings at 3 m intervals are available from this section and are stored at the BMR Core and Cutting Laboratory, Fyshwick, ACT. The section consists almost entirely of sandstone, quartzose, white, weathering brown, fine-grained, subrounded to subangular, dolomitic in parts, with sparse beds of claystone, white, soft, silty, fissile, tight, between 5 and 20 m, and rare beds of claystone, silty, dark brown or white, and chert, grey, cryptocrystalline, harad, and dolomite, white, micro-crystalline, hard throughout remainder of section.|16-MAY-23
10668|Lothari Hill Sandstone|Extent|The unit is poorly exposed over the north, central and southwest of Tanami East SE 52-16, the extreme south of Winnecke Creek SE 52-12, and the north half of Green Swamp Well SE 53-13 1:250 000 Sheet areas. Its southward extent into the Lander Trough on Lander River SF 53-1, 1:250 000 Sheet area, is not known.|16-MAY-23
10668|Lothari Hill Sandstone|Thickness range|Maximum recorded thickness is 94 metres in BMR Green Swamp Well 4.|16-MAY-23
10668|Lothari Hill Sandstone|Lithology|Sandstone, typically red-brown in outcrop (probably due to lateritization), white in parts, poorly sorted, finely grained, clayey, grades to clayey siltstone and claystone in parts; contains vertical burrows, mudcracks, and although typically thickly bedded and even textured, some low angle crossbedding is present.|16-MAY-23
10668|Lothari Hill Sandstone|Relationships and boundaries|Conformably overlies the Hooker Creek Formation with a gradational contact, as shown by cuttings from BMR stratigraphic drilling, and as exposed at Lothari Hill. Unconformably overlain by the Point Wakefield Beds in BMR Green Swamp Well 3, by the Lake Surprise Sandstone in the southwest of Tanami East Sheet area (contact not observed) and by the Buchanan Hills Beds at Buchanan Hills; upper contact eroded and covered by Cainozoic deposits throughout most of the Wiso Basin|16-MAY-23
10668|Lothari Hill Sandstone|Age reasons|Unfossiliferous; conformably overlies the Lower Middle Cambrian (Ordian) Hooker Creek Formation (J. Gilbert-Tomlinson, BMR pers. Comm. 1976). Unconformably overlain by the lower Middle Cambrian (Templetonian) Point Wakefield Beds (P. Jell, Univ. Qld pers. comm., 1976). Hence the Lothari Hill Sandstone is of lower Middle Cambrian age, probably deposited conformably and gradationally on the Hooker Creek Formation during the Ordian stage of Cambrian time.|16-MAY-23
10668|Lothari Hill Sandstone|Defn author|Kennewell P.J., 1978|16-MAY-23
10668|Lothari Hill Sandstone|Proposed publication|Bureau of Mineral Resources Bulletin|16-MAY-23
22219|Lovely Hill Schist|Name source|Lovely Hill (informal), used by Teyssier et al. (1988) for prominent hill at approximately 133o 11' E, 23o 41' S.|16-MAY-23
22219|Lovely Hill Schist|Unit history|Previously mapped as metamorphic lithological types (Majoribanks, 1974; Offe, 1981). Includes the "Potrock" gneiss of Majoribanks & Blakc (1974).|16-MAY-23
22219|Lovely Hill Schist|Geomorphic expression|Low rough hills.|16-MAY-23
22219|Lovely Hill Schist|Type section locality|Directly north of Lovely Hill from Gr 310700 7381800 to GR 312100 7381800, MacDonnell Ranges 1:100 000 Sheet area.|16-MAY-23
22219|Lovely Hill Schist|Extent|North of the Chewings Range, from Paisley Bluff to north of Ormiston Pound.|16-MAY-23
22219|Lovely Hill Schist|Lithology|Two-mica schist, schistose garnet-biotite gneiss, fine-grained quartzofeldspathic gneiss, quartzite.|16-MAY-23
22219|Lovely Hill Schist|Relationships and boundaries|Part of Iwupataka Metamorphic Complex of Offe and Shaw 1983, (see also Stewart et al., 1980). May in part overlie Ellery Granitic Complex, also intruded by Ellery Granitic Complex and by Brinkley Bluff Gneiss. Overlain by Chewings Range Quartzite.|16-MAY-23
22219|Lovely Hill Schist|Structure and Metamorphism|Complexly folded and metamorphosed during the Chewings Orogeny at about 1600 Ma (Teyssier et al., 1988; Collins & Shaw in press).|16-MAY-23
22219|Lovely Hill Schist|Age reasons|Middle Proterozoic: affected by regional metamorphism at about 1590 Ma (from Majoribanks & Black, 1974).|16-MAY-23
22219|Lovely Hill Schist|Correlations|Laterally equivalent to Ryans Gap Metamorphics and to Simpsons Gap Metasediments.|16-MAY-23
22219|Lovely Hill Schist|Defn author|R.D. Shaw & G.A. Wakelin-King, 22 May 1991.|16-MAY-23
22219|Lovely Hill Schist|Comments|This 'definition' is missing the details of references mentioned in the synonymy and age, and shows no signs on the card of having been approved.|16-MAY-23
79260|Loves Creek Formation|Name source|The Loves Creek Formation is named after Loves Creek (GDA94 53k 434984mE 7390519) that runs parallel with the Ross Highway about 1 km west of the turn off to Trephina Gorge National Park and joins the Ross River further downstream.|16-MAY-23
79260|Loves Creek Formation|Unit history|The Loves Creek member was proposed by Wells et al (1967), where it was suggested that the member be split into 2 units: a lower stromatolitic unit and an upper basaltic unit. In subsequent publications, Johnnys Creek member (beds) has been used for the upper basaltic unit, while Loves Creek member was retained for the lower stromatolitic unit (Ambrose 2006, Marshall 2004)|16-MAY-23
79260|Loves Creek Formation|Geomorphic expression|Outcrops of Loves Creek Formation dolostone tend to form steep rounded hills, while limestone forms narrow ridges.|16-MAY-23
79260|Loves Creek Formation|Type section locality|(type area) The area with the best preserved stromatolites is a sheer cliff-face at GDA94 53K 448534mE 7392568mN, near the Ross River Homestead.|16-MAY-23
79260|Loves Creek Formation|Description at type locality|The Ross River Homestead area has a number of sites where Acaciella australica assemblage stromatolites that are characteristic of the formation are well preserved. Throughout the Ross River area (ALICE SPRINGS), where Loves Creek member unit 1 (of Wells et al,1967) is mapped, these are the stromatolitic dolostones that are now proposed to be Loves Creek Formation.|16-MAY-23
79260|Loves Creek Formation|Extent|Currently mapped exposures of the Loves Creek Formation typically include the Johnnys Creek Formation, often mapped as unit 2; therefore the extent of the formation is approximate. The Loves Creek Formation is widespread across the northern margin of the basin, following a trend similar to the dominant Heavitree Quartzite ridge that extends across much of HERMANNSBERG, ALICE SPRINGS and ILLOGWA CREEK. Exposures of the Loves Creek Formation have also been observed in the northern parts of HALE RIVER, RODINGA and HENBURY. At times, exposures are recorded as undivided Bitter Springs Formation.|16-MAY-23
79260|Loves Creek Formation|General description|The Loves Creek Formation generally outcrops as a recrystallised carbonate rock; stromatolites are common although not always present. The unit is thinly bedded to massive, where the unit is bedded, ferruginised chert or siltstone beds are often observed.|16-MAY-23
79260|Loves Creek Formation|Thickness range|The thickness of the Loves Creek Formation cannot be determined accurately as the majority of observed sections are in areas where faulting and folding has occurred. The thickness of the Loves Creek Formation reported by Wells et al (1967) is approximately 500 m, however, approximately 290 m of this is upper Loves Creek Formation (later identified as Johnnys Creek Formation), leaving approximately 200 m of Loves Creek Formation. At Ellery Creek, the Loves Creek Formation is approximately 450 m thick (Wells et al 1967), however this also includes sediments that have now been identified as the Johnnys Creek Formation.|16-MAY-23
79260|Loves Creek Formation|Lithology|The Loves Creek Formation consists predominantly of stromatolitic dolostone and intercalations of chert, dolostone and minor limestone. The best exposure in the type area within the Ross River Homestead area (GDA94 53K 448534mE 7392568mN) is a sheer cliff approximately 12 m high which is part of an east-west striking ridge. The lower most part of the Loves Creek Formation is either not exposed or is absent due to faulting. Preserved in the cliff face is a series of upward shallowing cycles composed of stromatolitic biostromes. The lower-most cycle is composed of a well-developed unit of ooid grainstone which is overlain by an interval of stratiform stromatolites and thin beds of mudstone with chert. This is overlain by a number of cycles containing varying species of Acaciella australica assemblage stromatolites.|16-MAY-23
79260|Loves Creek Formation|Depositional environment|Southgate (1991) interpreted the basal unit of the Loves Creek Formation as a transgressive unit (systems tract). Upward changes in stromatolite forms and intercolumnar sediment infill were interpreted by Southgate (1991) to result from a gradual deepening of the water with which stromatolite growth kept pace. Individual cycles in the stromatolite-dominant unit were interpreted to be asymmetric shallowing upward parasequences.|16-MAY-23
79260|Loves Creek Formation|Fossils|Stromatolite forms include cylindrical, non-branching moderately convex ('finger-like') stromatolites of Acaciella affinities. The stromatolites of the Loves Creek Formation include Inzeria inita, Linella avis, Basisphera irregularis, Boxonia pertakurra, Kulparia alicia, and Minjaria pontifera, all of which are part of the Acaciella australica assemblage (Grey 2005). Common forms of spheroidal acritarchs have also been observed in the Loves Creek Formation (Zang and Walter 1992).|16-MAY-23
79260|Loves Creek Formation|Relationships and boundaries|The Loves Creek Formation locally overlies the Gillen Formation disconformably, whereas, Shaw et al (1982) suggested a conformable contact with the Gillen Formation on ILLOGWA CREEK. Menpes (1991) reported an unconformity between Gillen and Loves Creek formations in drillhole Murphy-1, and Camacho et al (2014) have suggested that this may correspond with a substantial time break. The contact of the Loves Creek Formation with the overlying Johnnys Creek Formation is conformable. This was observed near Shannon Bore (GDA 94 53K 457389mE 7376383mN). In other places the contact was either obscured (such as at 53J 511903mE 7335200mN) or has been removed due to faulting. Other reported contacts (e.g. Shaw et al 1982, Wells et al 1970, Wells et al 1967) are likely to be contacts with the Johnnys Creek Formation rather than the Loves Creek Formation.|16-MAY-23
79260|Loves Creek Formation|Identifying features|The most distinguishing characteristic feature of the Loves Creek Formation is the diverse content of distinctive stromatolites.|16-MAY-23
79260|Loves Creek Formation|Structure and Metamorphism|The Loves Creek Formation is extensively folded and faulted.|16-MAY-23
79260|Loves Creek Formation|Age reasons|The Bitter Springs Group and hence the Loves Creek Formation age is constrained to approximately 820 Ma based on geochemical correlation of the basalt from the Johnny Creek Formation (upper unit 2 of Wells et al, 1967) with the Amata Dolerite in the Musgrave Province.|16-MAY-23
79260|Loves Creek Formation|Correlations|None known, the Bitter Springs Group correlates generally with the Pinyinna beds.|16-MAY-23
79260|Loves Creek Formation|Alteration and Mineralisation|Copper: Copper mineralisation has been identified at Bronco Bore Cu Prospect in the Loves Creek Formation (Edgoose 2013). Manganese: The Fenn Gap Mn prospect located in the MacDonnell Ranges has manganese mineralisation within the dolostone of the Loves Creek Formation. Up to 50% Mn was discovered within chip samples collected by NTGS in 1970 (Edgoose 2013). Petroleum: The Loves Creek Formation is included in the middle Neoproterozoic petroleum system (system 2 of Marshall et al 2007) and has been identified as a potential source rock. Munson (2014) suggests the Loves Creek Member has excellent source potential in the eastern part of the basin.|16-MAY-23
79260|Loves Creek Formation|Defn author|VJ Normington, N Donnellan 28-SEP-2015. Approved: Stefan Kraus and Verity Normington 9-OCT-2015.|16-MAY-23
79260|Loves Creek Formation|References|Ambrose GJ, 2006. Northern Territory of Australia, Onshore hydrocarbon potential 2006. Record 2006-003: in Survey NTG (editor). Darwin. **Camacho A, Armstrong R, Davies P and Bekker A, 2014. Early history of the Amadeus Basin: implications for the existence and geometry of the Centralian Superbasin. Precambrian Research. **Edgoose C, 2013. Amadeus Basin: in Ahmad M and Munson TJ (editors) 'Geology and mineral resources of the Northern Territory; Special Publication 5', Northern Territory Government. **Grey K, 2005. Ediacaran palynology of Australia. Association of Australasian Palaeontologists Memoir 31. **Marshall TR, 2004. A review of source rocks in the Amadeus Basin: in Northern Territory Geological Survey R- (editor). **Marshall TR, Dyson IA and Liu Keyu, 2007. Petroleum systems in the Amadeus Basin, central Australia: Were they oil prone?: in Munson TJ and Ambrose GJ (editors) 'Proceedings of the Central Australian Basins Symposium, Alice Springs, 16 ¿ 18th August, 2005'. Alice Springs, Northern Territory Geological Survey, Special Publication 2, 136-146. **Menpes SA, 1991. Murphy No. 1 well completion report. Pacific Oil & Gas Pty Ltd. NTGS Open File Petroleum Report PR 1991-0021: in Survey NTG (editor). **Munson TJ, 2014. Petroleum geology and potential of the onshore Northern Territory, 2014, Northern Territory Geological Survey, Report 22. **Normington VJ and Donnellan N, in prep. Characterisation of the Neoproterozoic stratigraphy of the northeast Amadeus Basin, Northern Territory. Record 2015-##, Northern Territory Geological Survey. **Shaw R, Freeman M, Offe L and Senior B, 1982. Geology of the Illogwa Creek 1: 250 000 sheet area, central Australia: preliminary data BMR Record 1982/23, Australia. **Southgate PN, 1991. A sedimentological model for the Loves Creek Member of the Bitter Springs Formation, northern Amadeus Basin: in Korsch RJ and Kennard J (editors) 'Geological and geophysical studies in the Amadeus Basin, central Australia. ' Bulletin 236. Australia, Bureau of Mineral Resources, 113-126. **Wells AT, Forman DJ, Ranford LC and Cook PJ, 1970. Geology of the Amadeus Basin, Central Australia BMR Bulletin 100, Australia. **Wells AT, Ranford LC, Stewart AJ, Cook PJ and Shaw R, 1967. Geology of the north-eastern part of the Amadeus Basin, Northern Territory BMR Report 113, Australia. **Zang W and Walter MR, 1992. Late Proterozoic and Cambrian microfossils and biostratigraphy, Amadeus Basin, central Australia. Association of Australasian Palaeontologists Memoir 12.|16-MAY-23
29769|Madderns Yard Metamorphic Complex|Name source|Madderns Yard 132o17'E, 23o28's.|16-MAY-23
29769|Madderns Yard Metamorphic Complex|Constituents|Glen Helen Metamorphics, unnamed metamorphics north of Brinkley Bluff (map symbol PLmo), unnamed orthogneiss west of Old Hamilton Downs homestead (map symbol PLgk), may include units in the Alice Springs and Mount Liebig Sheet areas.|16-MAY-23
29769|Madderns Yard Metamorphic Complex|Extent|Southern Province of the Arunta Block, north of the Chewings Range, from west of Old Hamilton Downs homestead into the Mount Liebig Sheet area (western limit unmapped); may extend east into the Alice Springs Sheet area.|16-MAY-23
29769|Madderns Yard Metamorphic Complex|Lithology|Metamorphic rocks, mainly of felsic composition. Includes granitic, volcanic and sedimentary protoliths.|16-MAY-23
29769|Madderns Yard Metamorphic Complex|Relationships and boundaries|Intruded by the Ellery Granitic Complex, Brinkley Bluff Gneiss, Ormiston Pound Granite, Teapot Granite Complex, Dashwood Gabbro Complex, Stuart dykes, forms basement to the Iwupataka Metamorphic Complex; overlain by Heavitree Quartzite.|16-MAY-23
29769|Madderns Yard Metamorphic Complex|Structure and Metamorphism|Several episodes of deformation and metamorphism.|16-MAY-23
29769|Madderns Yard Metamorphic Complex|Age reasons|Middle Proterozoic. Glen Helen Metamorphics contain zircon with an age of 1670 Ma (rare cores at 1730 Ma, Black & Shaw, 1992b).|16-MAY-23
29769|Madderns Yard Metamorphic Complex|Correlations|Madderns lithological assemblage (informal) of Collins & Shaw (in press). Dyke rocks of Madderns Yard Granite, mentioned in preliminary outline by Warren (1991), now placed in the Teapot Granite Complex. The older gneissic rocks near Madderns Yard belong to the Glen Helen Metamorphics, part of the Madderns Yard Metamorphic Complex.|16-MAY-23
29769|Madderns Yard Metamorphic Complex|Defn author|R D Shaw & R G Warren. 11/10/95|16-MAY-23
29769|Madderns Yard Metamorphic Complex|Comments|This 'definition' is missing the details of references mentioned in the synonymy, and shows no signs on the card of having been approved.|16-MAY-23
22242|Maidjunga Member|Name source|Maidjunga River, a south-flowing fresh-water tributary of the Koolatong River which runs adjacent to the eastern margin of the Mitchell Range, Arnhem Bay and Blue Mud Bay 1:250 000 scale mapsheet areas.|16-MAY-23
22242|Maidjunga Member|Unit history|Previously undifferentiated Fagan Volcanics. Equates roughly to the informal "basal member A" of Plumb and Roberts (1922).|16-MAY-23
22242|Maidjunga Member|Geomorphic expression|Forms recessive valleys adjacent to the upstanding ridges of the enclosing sandstone units. Tors and weathered boulders are the common outcrop pattern.|16-MAY-23
22242|Maidjunga Member|Type section locality|The best probably complete sections of porphyritic rhyolite and associated volcaniclastic rocks are in the Blue Mud Bay map sheet area, where access is restricted to helicopter. The type section follows the Koolatong River near latitude 13o04'45"S, longitude 135o32'20". This section runs between AMG NF589537 (base of section) and NF581543 (top boundary stratotype). The basal contact here is unexposed and may be intrusive. Consequently, a lower boundary stratotype is defined to the north at NF680840 (Arnhem Bay map sheet area), where it is a sinuous and scalloped boundary between coarse-grained lithic sandstone of the Ritarango Formation and mildly foliated porphyritic rhyolite of the overlying Maidjunga Member (Fagan Volcanics).  Reference Areas: A volcaniclastic sequence exposed near the type section at NF600600 is nominated as a reference area. There are no complete or unfaulted sections in the Arnhem Bay map sheet area, where road access is good. However, given the uniformity of rock-type throughout the Mitchell Range, two reference areas of incomplete or fault-bounded outcrop are nominated. Area one comprises coarsely-porphyritic rhyolite in the core of a broad syncline on trhe eastern margin of the range near NF680840 (also the lower boundary stratotype). Area two is outcrop of mildly deformed possibly intrusive or fault-bounded rhyolite adjacent to the Gove-Bulman road near NF700960.|16-MAY-23
22242|Maidjunga Member|Extent|Outcrop occurs in two distinct areas in the northern and southern parts of the Mitchell Range, in both Arnhem Bay and Blue Mud Bay 1:250 0000 scale mapsheet areas. The areas are separated by a considerable distance (~30 km)|16-MAY-23
22242|Maidjunga Member|Thickness range|150-250 m, but is absent around NF490540 due to intraformational erosion.|16-MAY-23
22242|Maidjunga Member|Lithology|Undeformed to mildly deformed, coarsely-porphyritic K-feldspar-quartz-albite rhyolite, associated with minor fine- to coarse-grained volcaniclastic sandstone and mudstone, and rare dolerite. Ripples and trough cross-beds are common, while synsedimmentary deformation structures are rare in the sedimentary rock. Rocks arae locally sheared.|16-MAY-23
22242|Maidjunga Member|Depositional environment|Sedimentary volcaniclastic facies are fluvial. Igneous rocks are interpreted as flows and shallow sills.|16-MAY-23
22242|Maidjunga Member|Relationships and boundaries|Lies with conformity or mild disconformity on the coarse-grained siliciclastic rocks of the Ritarango Formation, and in turn is overlain conformably by the sandstone-mudstone succession of the Sheridan Member. The basal contact surface is often very sinuous, scalloped or crenulated in a north-south orientation on a scale of 10-100 m. This feature is most obvious on the aerial photograph. It is ascribed to either; a manifestation of the structural contrast between sandstones of the Ritarango Formation and porphyritic rhyolite of the Maidjunga Member; or syndepositional loading; or an irregular erosive (disconformity) surface. This problem remains unresolved. The upper boundary with the Sheridan Member in many areas takes the form of a conformable volcanic-epiclastic relationship, where porphyritic rhyolite is overlain by progressively more mature volcaniclastic sandstone. In the vicinity of NF490540 (Blue Mud Bay), the Maidjunga Member is absent (by erosion) and the Ritarango Formation is disconformably overlain by the Sheridan Member of the Fagan Volcanics.|16-MAY-23
22242|Maidjunga Member|Age reasons|Palaeoproterozoic (Statherian). Well constrained by single grain SHRIMP U-Pb geochronological techniques at ~1710 Ma (Rawlings and others, in prep.). The rhyolite porphyry sample used was collected from outcrop at NF694959.|16-MAY-23
22242|Maidjunga Member|Correlations|Rawlings and others (in prep.) and Rawlings (1994) suggest correlation with the upper parts of the Tawallah and Katherine River Groups in the southern and western McArthur Basin respectively. More locally, it correlates to felsic igneous successions of the Spencer Creek Group in northeastern Arnhem Bay and tentatively with the Gadabara Volcanics in the eastern Blue Mud Bay mapsheet area. These correlations are based on geochemical, petrological, lithostratigraphic and geochronological constraints, and the physical form of igneous units.|16-MAY-23
22242|Maidjunga Member|Proposed publication|Arnhem Bay-Gove 1:250 000 Geological Map Series, Northern Territory, National Geoscience Mapping Accord, Explanatory Notes (Rawlings and others, in prep.).|16-MAY-23
22242|Maidjunga Member|Category|2|16-MAY-23
22242|Maidjunga Member|Defn approved by|Brakel A.T., Haines P.W.|16-MAY-23
22242|Maidjunga Member|Proposer|Rawlings D.J.|16-MAY-23
22242|Maidjunga Member|Reserved? Yes/No|Yes|16-MAY-23
27827|Maningkorrirr Phonolite|Name source|Maningkorrirr - a small aboriginal settlement on the Goomadeer River. 133o41'E, 12o6'S. Milingimbi 1:250 000 Sheet area.|16-MAY-23
27827|Maningkorrirr Phonolite|Type section locality|On Oenpelli-Maningrida track 1 km east of Mesozoic escarpment and 9 km west of Maningkorrirr junction. The track crosses 3 phonolite dykes trending NE, Se and SSE. 133o35'25"E, 12o9'45"S.|16-MAY-23
27827|Maningkorrirr Phonolite|Extent|50 km2 centred 8 km ENE of Jungle Creek headwater, and east of the low Mesozoic escarpment which makes the western edge of the Goomadeer River catchment.|16-MAY-23
27827|Maningkorrirr Phonolite|Thickness range|< 1 m wide, genrally 30-60 cm wide, and up to 1 km long.|16-MAY-23
27827|Maningkorrirr Phonolite|Lithology|Fine to medium grained to porphyritic grey green dyke rock. Phenocrysts of euhedral anorthoclase and sanidine tablets and zoned aegirine-augites < 3 cm. Some pyroxenes rimmed by a pleochroic green sodic amphibole which occurs in the groundmass. Groundmass is generally strongly altered, consisting essentially of sanidine-anorthoclase, aegirine-augite (altering to a fibrous sodic amphibole), biotite and titanomagnetite with accessory sphene.|16-MAY-23
27827|Maningkorrirr Phonolite|Relationships and boundaries|Straight parallel-sided steeply dipping dykes with sharp boundaries cutting granitoid migmatite of the Nimbunah Complex. Typically hybrid and contain xenoliths of the country rock.|16-MAY-23
27827|Maningkorrirr Phonolite|Age reasons|Approx. 1350 m.y. Total rock Rb-Sr isochron. K-Ar data yield unrealistic spread of dates from 2100 to 600 m.y. Page & Needham (in prep.).|16-MAY-23
27827|Maningkorrirr Phonolite|Proposed publication|Journal of the Geological Society of Australia|16-MAY-23
33647|Mantapayika Granite|Name source|Mantapayika outstation; 25o35'10.5"S, 129o27'51.4"E, Petermann Ranges.|16-MAY-23
33647|Mantapayika Granite|Unit history|Comprises part of the Olia Gneiss of Forman (1966, 1972).|16-MAY-23
33647|Mantapayika Granite|Constituents|Nil. Forms part of the Umutju Granite Suite.|16-MAY-23
33647|Mantapayika Granite|Geomorphic expression|Low rocky hills and pavements, widely scattered with extensive Cainozoic cover.|16-MAY-23
33647|Mantapayika Granite|Type section locality|Porphyritic granite: Isolated outcrop of granite at 25o43'33.7"S, 129o57'14.5"E. Reference locality: migmatitic garnet-hornblende gneiss: Pavement near Wingellina-Docker River road at 25o38'25.9"S, 129o11'57.3"E.|16-MAY-23
33647|Mantapayika Granite|Extent|Throughout a region of 2500-3000 km2 north of the Mann Ranges encompassing the northern half of the Cockburn and Duffield 1:100 0000 sheet areas, Petermann Ranges.|16-MAY-23
33647|Mantapayika Granite|Lithology|Variably mylonitised porphyritic clinopyroxene granite, with rounded blue-grey K-feldspar phenocrysts, typically 1-3 cm but up to 6 cm in diameter. Less common weakly porphyritic to equigranular phases occur, locally containing primary hornblende. The primary granite mineralogy is overprinted by a mylonitic fabric defined by quartz, feldspar, garnet, clinopyroxene and biotite, with or without hornblende. Migmatitic gneisses occur in zones of high strain, and contain partial melts and biotite-hornblende-garnet-sphene bearing assemblages.|16-MAY-23
33647|Mantapayika Granite|Relationships and boundaries|No contacts exposed with other granites. Intruded by mafic dykes of the Alcurra and Amata Dyke Swarms. Truncated to the north by the Woodroffe Thrust.|16-MAY-23
33647|Mantapayika Granite|Age reasons|Mesoproterozoic. Part of the Umutju Granite Suite, dated elsewhere at 1180-1140 Ma.|16-MAY-23
33647|Mantapayika Granite|Correlations|Very simialar to Walytjatjata and Puka Granites, with only minor textural and geochemical differences. Similar age to Pottoyu and Mantarurr Granite Suites, Petermann Ranges.|16-MAY-23
33647|Mantapayika Granite|Proposed publication|Petermann Ranges 1:250 000 geological mapsheet Explanatory Notes|16-MAY-23
33647|Mantapayika Granite|Category|2|16-MAY-23
33647|Mantapayika Granite|Defn approved by|Beier P., Kruse P.D., Young D.N.|16-MAY-23
33647|Mantapayika Granite|Proposer|Scrimgeour I.R., Close D.F., Edgoose C.J.|16-MAY-23
33648|Mantarurr Granite Suite|Name source|Mantarurr outstation, 25o35'7.9"S, 130o27'34.8"E, Petermann Ranges.|16-MAY-23
33648|Mantarurr Granite Suite|Unit history|Comprises part of the Olia Gneiss and unnamed metamorphosed granites of Forman (1966, 1972).|16-MAY-23
33648|Mantarurr Granite Suite|Constituents|Utanta Granite, Foster Cliff Granite, Wala Wuru Granite, Kulu Granite.|16-MAY-23
33648|Mantarurr Granite Suite|Geomorphic expression|Low outcrops and rounded hills. Rubbly slopes underlying quartzite scarps in Olia Chain.|16-MAY-23
33648|Mantarurr Granite Suite|Type section locality|Type localities for the respective constituent formations are given in their respective formal definitions.|16-MAY-23
33648|Mantarurr Granite Suite|Extent|Throughout the Olia Chain and in low outcrops extending 20 km south and southwest of Foster Cliff on Petermann Ranges.|16-MAY-23
33648|Mantarurr Granite Suite|Lithology|Texturally variable biotite-rich foliated granites. The mineralogy typicaly comprises quartz, K-feldspar, plagioclase, biotite, sphene, ilmenite and muscovite, with or without allanite and garnet. The granites are typically variably porphyritic, with rectangular to sub-rounded K-feldspar phenocrysts up to 5 cm in diameter. Large areas are finely porphyritic to equigranular.|16-MAY-23
33648|Mantarurr Granite Suite|Relationships and boundaries|Intrudes c.1550-1600 Ma amphibolite facies felsic gneiss. Intruded by 1078 Ma Alcurra Dyke Swarm and 800 Ma Amata Dyke Swarm.|16-MAY-23
33648|Mantarurr Granite Suite|Age reasons|Mesoproterozoic. SHRIMP U-Pb zircon age of c.1168 +/- 14 Ma (M. Fanning, pers. comm.) for the Kulu Granite (25o43'52.3"S, 130o19'51.1"E).|16-MAY-23
33648|Mantarurr Granite Suite|Correlations|Similar age, but geochemically distinct from the Pottoyu and Umutju Granite Suites and Walal Granite on Petermann Ranges.|16-MAY-23
33648|Mantarurr Granite Suite|Proposed publication|Petermann Ranges 1:250 000 geological mapsheet Explanatory Notes|16-MAY-23
33648|Mantarurr Granite Suite|Comments|Deformed and metamorphosed at 5-6 kbars and 600-650oC during the c.560 Ma Petermann Orogeny.|16-MAY-23
33648|Mantarurr Granite Suite|Category|2|16-MAY-23
33648|Mantarurr Granite Suite|Defn approved by|Beier P., Kruse P.D., Young D.N.|16-MAY-23
33648|Mantarurr Granite Suite|Proposer|Close D.F., Scrimgeour I.R., Edgoose C.J.|16-MAY-23
25203|Manton Group|Name source|After Manton Dam, 22 km NNE of Batchelor, Northern Territory.|16-MAY-23
25203|Manton Group|Unit history|Referred to as Namoona Group (Crick 1987, Pietsch and Stuart-Smith 1987, Needham et al 1988).|16-MAY-23
25203|Manton Group|Constituents|Beestons Formation and Celia Dolostone.|16-MAY-23
25203|Manton Group|Extent|The Manton Group occurs around the southern and eastern margins of the Rum Jungle Dome and the eastern margin of the Waterhouse Dome in NOONAMAH, REYNOLDS RIVER and BATCHELOR 1:100 000 sheets.|16-MAY-23
25203|Manton Group|Relationships and boundaries|Beestons Formation unconformably overlies Rum Jungle Complex. Celia Dolostone is unconformably overlain by Crater Formation conglomerate and arkose. Lower boundary is recognised as the change from Rum Jungle Complex granite, granite-gneiss or schist to quartz conglomerate of the Beestons Formation. Upper boundary is recognised by sudden change from Celia Dolostone (commonly not exposed) to ridge-forming arkose and conglomerate of the Crater Formation.|16-MAY-23
25203|Manton Group|Age reasons|Younger than 2507 Ma, age of the youngest detrital zircons in the Beestons Formation (NTGS unpublished data), and older than 1885 Ma, age of the South Alligator Group (Needham et al 1988).|16-MAY-23
25203|Manton Group|Correlations|Possibly equivalent to Namoona Group in central Pine Creek Orogen.|16-MAY-23
25203|Manton Group|Comments|The name Manton Group was previously used to group Beestons Formation and Celia Dolostone, but was not formally defined (Pietsch 1983, Pietsch 1985). Subsequent publications (eg Pietsch and Stuart-Smith, 1987) classified Beestons Formation and Celia Dolostone as Namoona Group, based on a tentative correlation with the Masson Formation in the central PCO. No geochronological data are available to determine whether the Masson Formation and Manton Group are time equivalents. From its distribution around the Rum Jungle Complex, the Manton Group appears to have formed in a shallow water environment restricted to the margins of a basement high formed by the Rum Jungle Complex.|16-MAY-23
27478|Mapata Gneiss|Name source|After Mapata Creek which is centrally placed with respect to the outcrop areas. Mapata Creek is a tributary of Bundey Creek in the eastern part of the Alcoota 1:250 000 Sheet area, SF53-10, Australian Map Grid.|16-MAY-23
27478|Mapata Gneiss|Type section locality|Centred on 4755E, 75024N, possibly unconformable boundary with Delny Gneiss immediately to north. Boundary with Kanandra Granulite poorly exposed at 4833E, 75008N.|16-MAY-23
27478|Mapata Gneiss|Extent|Crops out in a belt from southeast of Delny homestead (GR.4813E, 7506N, AMG, metric) to west of Muller Bore (GR.448E, 7580N, AMG) exposures usually affected by deep weathering.|16-MAY-23
27478|Mapata Gneiss|Lithology|Biotite-quartz feldspar gneiss typically with quartzo-feldspathic segregations, biotite schist, amphibolite. All exposed in type area.|16-MAY-23
27478|Mapata Gneiss|Relationships and boundaries|Possibly conformably overlies the Kanandra Granulite which is of higher metamorphic age. The boundary with the Kanandra Granulite is probably isoclinally folded. Possibly unconformably beneath Delny Gneiss as boundary corresponds to a marked regional change in lithology. The Mapata Gneiss is intruded by the Crooked Hole, Copia, and Ida Granites and probably by the Mount Suan Granite.|16-MAY-23
27478|Mapata Gneiss|Identifying features|Distinguished from Delny Gneiss principally by presence of migmatic appearance and quartzofeldspathic segregations and lack of muscovite clots. Distinguished from Chiripee Gneiss by lack of garnet. Distinguished from Kanandra Granulite principally in containing a very much smaller proportion of mafic rock.|16-MAY-23
27478|Mapata Gneiss|Age reasons|Probably older than the Mount Suan Granite dated by Pb/Sr (T.T.) at 1690 m.y. Criley 1961 and pers. comm. in Compston and Arriens, 1968).|16-MAY-23
27478|Mapata Gneiss|Correlations|Tentative correlations: Probably equivalent in part to the Chiripee Gneiss, but lacks garnet.|16-MAY-23
27478|Mapata Gneiss|Proposed publication|BMR Report|16-MAY-23
27478|Mapata Gneiss|Name first published by|Shaw R.D., Warren R.G., Kopras J., Green D.E., 1995.|16-MAY-23
27478|Mapata Gneiss|Unit name|Mapata Gneiss (pCb)|16-MAY-23
11378|Marshall Granite|Name source|Marshall Bore (135.6263degreesE, 22.7771degreesS (GDA 2020)) in Jinka 1:100 000 mapsheet, Northern Territory.|16-MAY-23
11378|Marshall Granite|Unit history|First defined by Smith (1964). Freeman (1986) included additional lithologies into the Marshall Granite.|16-MAY-23
11378|Marshall Granite|Geomorphic expression|Best exposed in the Mopunga Range, where it forms steep sided, spinifex-covered hills. Away from the range, the Marshall Granite occurs as scattered blocky hills and rises, some capped with Cenozoic silcrete. On the plains between more prominent outcrops, the Marshall Granite occurs as deeply weathered outcrop and grus.|16-MAY-23
11378|Marshall Granite|Type section locality|Mopunga Range around 135.5656degreesE 22.7202degreesS (GDA2020); access off-track via 4x4.|16-MAY-23
11378|Marshall Granite|Description at type locality|Orange-pink weathered, undeformed granite. Inequigranular interlobate assemblage of fine- to medium-grained K-feldspar-quartz-biotite-muscovite. K-feldspar is tartan twinned microcline and is strongly altered. Mica is uncommon and consists of minor altered biotite and rare secondary muscovite. Opaque oxides comprise approximately 1 vol% of the mineral mode and are disseminated in the matrix.|16-MAY-23
11378|Marshall Granite|Extent|East of Little Frazer Creek and west of the Elua Range, south of the Dulcie Range and north of the Marshall River in HUCKITTA 1:250 000 mapsheet (Weisheit et al in prep).|16-MAY-23
11378|Marshall Granite|General description|Granite, pegmatite, rare aplite: fine- to coarse-grained, equigranular, locally porphyritic, leucocratic, locally developed biotite; strongly weathered; locally silica-, epidote-, chlorite-, or sericite-altered, brecciated, rarely mineralised; undeformed, locally foliated to mylonitic.|16-MAY-23
11378|Marshall Granite|Lithology|Orange-pink weathered, undeformed granite. Inequigranular interlobate assemblage of fine- to medium-grained K-feldspar-quartz-biotite-muscovite. K-feldspar is tartan twinned microcline and is strongly altered. Mica is uncommon and consists of minor altered biotite and rare secondary muscovite. Opaque oxides comprise approximately 1 vol% of the mineral mode and are disseminated in the matrix.|16-MAY-23
11378|Marshall Granite|Depositional environment|Genesis: Formed via melting of thickened crust during a period of crustal stabilisation and relaxation towards the end of a regional Palaeoproterozoic tectonothermal event.|16-MAY-23
11378|Marshall Granite|Relationships and boundaries|Anatectic granite derived from partial melting of Dinkum Orthogneiss; intrudes Deep Bore Metamorphics, rocks of the Baikal Supersuite and Black Label Suite, and Yam Gneiss. Nonconformity with Neoproterozoic Oorabra Arkose and Grant Bluff Formation, and possible Devonian Dulcie Sandstone of Georgina Basin.|16-MAY-23
11378|Marshall Granite|Identifying features|Characteristic pink K-feldspar; commonly orange-pink weathered. Commonly associated with pink K-feldspar-quartz hydrothermal rocks.|16-MAY-23
11378|Marshall Granite|Structure and Metamorphism|Deformation ranges from undeformed away from the Delny Shear Zone to foliated or locally mylonitic where it outcrops proximal to, and within the Delny Shear Zone. Anatectic granite that formed during regional amphibolite- to granulite-facies metamorphism.|16-MAY-23
11378|Marshall Granite|Age reasons|Apatite LA-ICP-MS age of 1732 +/- 4 Ma for Marshall Granite at the Molyhil tungsten?molybdenum deposit (135.7510degreesE 22.7595degreesS (GDA 2020)) is interpreted to record timing of main granite crystallisation (Reno et al 2021). Minor late-stage aplite dykes formed at 1720 +/- 18 Ma (igneous crystallisation, SHRIMP zircon, Kositcin et al 2018).|16-MAY-23
11378|Marshall Granite|Correlations|Interpreted as co-magmatic and co-genetic with Jinka Granite, both constituent units of the Sainthill Suite, based on similar geochemical and isotopic composition, and timing of structural fabric development.|16-MAY-23
11378|Marshall Granite|Alteration and Mineralisation|Silicification of the Marshall Granite is common in areas where the granite is intruded by white quartz veins. Interpreted as the driver for skarn alteration and associated W-Mo mineralisation at Molyhil W-Mo deposit and nearby prospects (McGloin and Weisheit 2021).|16-MAY-23
11378|Marshall Granite|Geophysical Expression|Moderate-low gravity signal; difficult or indistinguishable from surrounding (meta-)igneous units. Associated with gravity low and radiometric high responses.|16-MAY-23
11378|Marshall Granite|Geochemistry|Monzogranite and syenogranite. ASI values from 0.94-1.15 indicating compositions that are moderately metaluminous to moderately peraluminous. LREE-enriched with HREEs that vary from flat to having slightly negative or positive slopes and weakly to strongly negative Eu anomalies. epsilonNd values range from -0.92 and -2.63, corresponding to crustal model ages of 2.39-2.26 Ga.|16-MAY-23
11378|Marshall Granite|Defn author|Barry Reno, Anett Weisheit, Eloise Beyer, Pablo Farias (NT Department of Industry, Tourism and Trade, Northern Territory Geological Survey) 3-MAY-2022.|16-MAY-23
11378|Marshall Granite|References|McGloin MV and Weisheit A, 2021. Epigenetic copper and tungsten mineralisation in JINKA and JERVOIS RANGE, northeastern Aileron Province. Northern Territory Geological Survey, Record.  **Kositcin N, Reno BL and Beyer EE, 2018. Summary of results. Joint NTGS-GA geochronology project: Aileron Province, July 2015-June 2016. Northern Territory Geological Survey, Record 2018-005.  **Reno BL and Fraser GL, 2021. Summary of results. Joint NTGS-GA geochronology project: Constraining cooling and deformation in the eastern Aileron Province through 40Ar/39Ar step-heating of hornblende, muscovite, and biotite. Northern Territory Geological Survey, Record 2021-001.  **Reno BL, McGloin MV, Thompson JM and Meffre S, 2021. Summary of results. Laser ablation ICP-MS in situ apatite geochronology of the Molyhil tungsten-molybdenum deposit and Prospect D nickel-copper prospect. Northern Territory Geological Survey, Record 2021-007.  **Reno BL, Weisheit A, Beyer EE and PG Farias, 2022. Jinka, Northern Territory. 1:100 000 geological map series explanatory notes, 6052. Northern Territory Geological Survey, Darwin.  **Smith KG, 1964. Progress report on the geology of the Huckitta 1:250 000 sheet, Northern Territory. Bureau of Mineral Resources, Geology and Geophysics, Australia, Report 67.  **Weisheit A, Reno BL and Beyer EE, 2019. Jervois Range Special, Northern Territory (First Edition). 1:100 000 geological map series, explanatory notes 6152 and part 6252. Northern Territory Geological Survey, Darwin.  **Weisheit A et al, in prep. Huckitta, Northern Territory. 1:250 000 geological map series explanatory notes, SF53-11. Northern Territory Geological Survey, Darwin.|16-MAY-23
80345|Mascotte Orthogneiss|Name source|Mount Mascotte (600562mE 7488138mN, GDA94, Zone53) in Jervois Range 1:100 000 mapsheet, Northern Territory.|16-MAY-23
80345|Mascotte Orthogneiss|Unit history|Previously assigned as part of the Mascotte Gneiss Complex of Shaw et al (1985) and Freeman et al (1986).|16-MAY-23
80345|Mascotte Orthogneiss|Geomorphic expression|The unit is generally poorly exposed, occurring as low, blocky outcrops or jointed pavements, with some larger outcrops forming isolated bouldery hills.|16-MAY-23
80345|Mascotte Orthogneiss|Type section locality|Bonya Hills at 609429mE 7487049mN (GDA94, Zone53); access via private tracks. Bonya Hills at 136.0655degreesE 22.7202degreesS (GDA2020) in JERVOIS RANGE; access via public roads and private tracks. Some off-track driving/walking might be required.|16-MAY-23
80345|Mascotte Orthogneiss|Extent|Bonya Hills east of the Charlotte Fault Zone (around 607837mE 7486133mN).|16-MAY-23
80345|Mascotte Orthogneiss|General description|Biotite granitic gneiss: fine- to medium-grained, equigranular, locally occurring allanite, rare hornblende. Biotite is commonly 3-7 vol%. Locally contains up to 20 vol% hornblende and clinopyroxene. Quartz is commonly recrystallised and has a granoblastic texture. Fresh to moderately weathered. Massive to foliated to gneissic with discontinuous mm- to cm-scale banding variably developed. Compositions are largely granite sensu stricto with monzogranite dominating over syenogranite.|16-MAY-23
80345|Mascotte Orthogneiss|Lithology|Orthogneiss; fresh and massive with an inequigranular, fine-grained assemblage composed of quartz-K-feldspar-plagioclase-biotite with an average grainsize of around 1 mm. Chlorite-after-biotite; plagioclase is largely sericitised.|16-MAY-23
80345|Mascotte Orthogneiss|Depositional environment|Continental margin environment, either arc cordillera or back arc basin, or derived from melting of pre-existing crust that formed in a continental margin environment.|16-MAY-23
80345|Mascotte Orthogneiss|Relationships and boundaries|Interlayered with the White Violet Orthogneiss and Kings Legend Metadolerite, both of the Baikal Supersuite; interpreted concordant intrusive contact with Bonya Metamorphics; intruded by the Cappocks Granodiorite, Jericho Granite, Thring Granite, and Samarkand Pegmatite.|16-MAY-23
80345|Mascotte Orthogneiss|Structure and Metamorphism|Compositionally layered, weakly boudinaged, overprinted by layer-parallel grain shape foliation; intruded prior to regional amphibolite facies high-thermal-gradient metamorphism.|16-MAY-23
80345|Mascotte Orthogneiss|Age reasons|Crystallisation of the igneous protolith to the Mascotte Orthogneiss occurred at 1789 +/- 3 Ma (SHRIMP 207Pb/206Pb zircon age, GA sample number 1999626 in Kositcin et al 2011).|16-MAY-23
80345|Mascotte Orthogneiss|Correlations|Interpreted as co-magmatic and co-genetic with constituent units of the Fosters and Casper suites, Baikal Supersuite based on similar geochemical and isotopic composition, and timing of structural fabric development.|16-MAY-23
80345|Mascotte Orthogneiss|Alteration and Mineralisation|Commonly chloritised and sericitised, locally silicified; varies from fresh to moderately weathered with a pink-orange to red-brown weathering rind; no known mineralisation.|16-MAY-23
80345|Mascotte Orthogneiss|Geophysical Expression|Magnetic low with locally developed magnetic high contact aureole; in area of gravity high; radiometric high signal.|16-MAY-23
80345|Mascotte Orthogneiss|Geochemistry|Dominantly moderately metaluminous to strongly peraluminous I-type monzogranite. Moderate to high LREE enrichment compared to MREE, and ubiquitous negative Eu anomalies.|16-MAY-23
80345|Mascotte Orthogneiss|Defn author|Anett Weisheit, Barry Reno, Eloise Beyer (Northern Territory Geological Survey) 29-JUN-2018.|16-MAY-23
80345|Mascotte Orthogneiss|Proposed publication|Weisheit A, Reno BL and Beyer EE, in review. Jervois Range Special, Northern Territory. 1:100 000 geological map explanatory notes, 6152 and part 6252. Northern Territory Geological Survey, Darwin.|16-MAY-23
80345|Mascotte Orthogneiss|References|Kositcin N, Beyer EE and Whelan JA, 2014b. Summary of results. Joint NTGS-GA SHRIMP geochronology project: Arunta Region, July 2013-June 2014. Northern Territory Geological Survey, Record 2014-008.  **Freeman MJ, Black LA, Offe LA, Senior BR, Shaw RD, Shergold JH, Simpson CJ, Walter MR, Warren RG, Donnellan N, Horsfall CJ, Laurie JR and Walley AM, 1986. Huckitta, Northern Territory (Second Edition). 1:250 000 geological map series, SF 53-11. Northern Territory Geological Survey, Darwin.  **Shaw, R.D., Warren, R.G., Freeman, M.J., 1985, Stratigraphic definitions of named units in the Arunta Block, Northern Territory, 1979-82., Bureau of Mineral Resources, Australia, Report, 260|16-MAY-23
24374|Maud Dolerite|Name source|Maud Creek, 20 km NE of Katherine NT on Katherine 1:250 000 Sheet area.|16-MAY-23
24374|Maud Dolerite|Unit history|Previously unnamed, but compard with "Zamu Complex" by Rattigan & Clarke (1955). Their age and relationships indicate they are significantly younger than the Zamu Complex, which is unconformably overlain by El Sherana Group. (The "Zamu Complex" has been renamed Zamu Dolerite (Ferguson & Needham, 1976). Dorothy Volcanics (Walpole & others, 1968) in part.  Included in Zamu Dolerite by Needham (1978). This unit is unrelated in all respects to the Maude Formation (Palaeozoic) in Victoria, and Maude Creek volcanics of the NT (now superseded by Leight Creek Volcanics).|16-MAY-23
24374|Maud Dolerite|Type section locality|Longitude 132o28'E, latitude 13o26'30"S. 1 km east of Maud Creek gold mining area (GR KE270020).|16-MAY-23
24374|Maud Dolerite|Extent|Around and between Maud Creek and Carpentaria Mining Areas in Katherine 1:100 000 Sheet area; also within 5 km of Ludans mine in Eva Valley 1:100 000 Sheet area (GR KE648247) (BMR 1984).|16-MAY-23
24374|Maud Dolerite|Thickness range|Sills about 200-500 m thick.|16-MAY-23
24374|Maud Dolerite|Lithology|Medium to coarse grained quartz dolerite; minor fine quartz dolerite. Patchy sericite-chlorite alteration.|16-MAY-23
24374|Maud Dolerite|Relationships and boundaries|Intrudes and hornfelses late Early Proterozoic Tollis Formation of El Sherana Group, mainly as sills, faulted contacts with Eva Valley Granite, unconformably overlain by Middle Proterozoic Kombolgie Formation of Katherine River Group. Locally distinct lithologies confined to this unit, intrusive contacts.|16-MAY-23
24374|Maud Dolerite|Structure and Metamorphism|Tightly folded about northerly axes, limbs dip mainly 40-60o.|16-MAY-23
24374|Maud Dolerite|Age reasons|Between c.1860 Ma (Needham & others in prep.) and 1650 Ma (Page & others 1980).|16-MAY-23
24374|Maud Dolerite|Correlations|Possible correlation: The age range embraces the c.1690 Ma age of the Oenpelli Dolerite (Stuart-Smith & Ferguson, 1978; Page & others 1980), but the degree of differentiation typical of the Oenpelli Dolerite is not present in the Maud Dolerite. The nearest outcrop of Oenpelli Dolerite is 65 km to the north, near Mount Evelyn.|16-MAY-23
24374|Maud Dolerite|Proposed publication|BMR 1:100 0000 Geological Map Commentary - Geology of the Edith River Region|16-MAY-23
24374|Maud Dolerite|Category|2|16-MAY-23
24374|Maud Dolerite|Proposer|Needham S.|16-MAY-23
30958|Melville Bay Metamorphics|Name source|Melville Bay, southwest of Nhulunbuy (Arnhem Bay-Gove).|16-MAY-23
30958|Melville Bay Metamorphics|Unit history|Outcrop now mapped as this unit was previously mapped as the 'Bradshaw Granite' by Dunnet (1965) and the 'Bremer type' of the Bradshaw Complex by Plumb and Roberts (1992), Madigan and Rawlings (1994) and Madigan and others(1995). These informal terms are now abandoned.|16-MAY-23
30958|Melville Bay Metamorphics|Geomorphic expression|The main outcrop areas comprise rounded tors and boulders, and bare pavements on the coastline.|16-MAY-23
30958|Melville Bay Metamorphics|Type section locality|Wargarpunda Point. Lat12degrees11' S, long 136degrees 41'30" E (AMG PG836524)|16-MAY-23
30958|Melville Bay Metamorphics|Extent|Shorelines of Bremer Island and at Wargarpunda Point, adjacent to the NABALCO treatment plant on Gove Peninsula (Arnhem Bay-Gove).|16-MAY-23
30958|Melville Bay Metamorphics|Lithology|Banded granulite with alternate dark, pelitic layers, and white, felsic layers. Scattered porphyroblasts of pink garnet up to 5 cm are present in both layer types. Pelitic layers are medium- to coarse-graned and comprise cordierite, garnet sillimanite, K-feldspar and biotitie with accessory hercynitic spinel, magnetite, ilmenite, zircon, rarre sericitised plagioclase and monazite. Felsic bands comprise garnet, quartz, plagioclase, orthopyroxene, sillimanite, cordierite and K-feldspar, with accessory magnetite, biotite, ilmenite, zircon and spinel or calcite, scapolite, quartz, clinopyroxene, wollastonite, plagioclase, and sphene. These bands have granoblastic texture, are fine- to medium-grained and massive to finely banded. the localised leucogranite veinsand pods comprose garnet, quartz, plagioclase, K-feldspar and cordierite with accessory spinel, biotite, magnetite, zircon, sillimanite. They are coarse-graned and have anhedral to subhedral granular consertal texture. Banding between layers represents primary bedding, while coeval foliation within layers represents the regional, high-grade metamorphic event and is defined by sillimanite and biotite. Both types of banding/foliation have been folded.|16-MAY-23
30958|Melville Bay Metamorphics|Relationships and boundaries|Metasedimentary part of the Bradshaw Complex. Overlain by Quaternary coastal sediments and alluvium.|16-MAY-23
30958|Melville Bay Metamorphics|Age reasons|The metamorphic age of this formation, from analysis of single zircon grains by SHRIMP U-Pb geochronological techniques is ~1850-1860 Ma (Page, pers. comm., 1995). Sample collected from PG837525.|16-MAY-23
30958|Melville Bay Metamorphics|Correlations|The Melville Bay Metamorphics are interpreted as the metamophosed equivalent of the sedimentary protolith that produced, through inhomogeneous melting, the Drimmie Head Granite. Broad correlation with the Nimbuwah and Mirarrmina Complexes and high-grade metamorphic portions of the Pine Creek succession.|16-MAY-23
30958|Melville Bay Metamorphics|Defn author|T. L. Madigan and D.J. Rawlings, 1997.|16-MAY-23
11649|Mendip Metamorphics|Name source|After Mendip Hill in centre of outcrop area. Mendip Hills (GR.4386E, 74827N AMG (metric) is in 'Alcoota' Station, central-southern Alcoota 1:250 000 Sheet area, SF 53-10, Australian map Grid.|16-MAY-23
11649|Mendip Metamorphics|Type section locality|Centred on Mendip Hill (GR.4386E, 74827N) and adjacent ridges 9 km northwest of 'Alcoota' homestead, central-southern Alcoota Sheet area.|16-MAY-23
11649|Mendip Metamorphics|Extent|Environs of Mendip Hills. Possible equivalents occur in the headwaters of Mapata Creek. Maximum extent of well classified exposures is 12 km.|16-MAY-23
11649|Mendip Metamorphics|Lithology|Quartzite, biotite-feldspar gneiss; minor granule conglomerate, para-amphibole and calc-silicate gneiss. All exposed in type area.|16-MAY-23
11649|Mendip Metamorphics|Relationships and boundaries|Possible major unconformity with the underlying Bleechmore Granulite suggested by marked differences in lithology and metamorphic grade.|16-MAY-23
11649|Mendip Metamorphics|Identifying features|Metamorphics has conformable contact with Langford Gneiss, but Langford Gneiss may have intruded the Mendip Metamorphics before metamorphism. Distinguished from Langford Gneiss by the first appearance of quartzite. Contact poorly exposed at 428E, 74825N AMG (metric).|16-MAY-23
11649|Mendip Metamorphics|Age reasons|Possibly Early Proterozoic|16-MAY-23
11649|Mendip Metamorphics|Correlations|Tentative correlations: Correlated with Ledan Schist, Utopia Quartzite|16-MAY-23
11649|Mendip Metamorphics|Proposed publication|BMR Report|16-MAY-23
11649|Mendip Metamorphics|Name first published by|Shaw, R.D., Warren R.G., Kopras J., Green D.E., 1975|16-MAY-23
26313|Mia Mia Volcanics|Name source|Mia Mia Creek in the southwest of the Hatches 1:100 0000 Sheet area, Frew River 1:250 000 Sheet area. The headwaters of this northerly flowing creek drain much of the outcrop area of the formation.|16-MAY-23
26313|Mia Mia Volcanics|Unit history|Corresponds to the Bottom Series of Hossfeld (1954 - Trans Roy. Soc. S. Aust, 77, 103-61; and in AGGSNA - Rep. For period ending 31 December 1940).|16-MAY-23
26313|Mia Mia Volcanics|Type section locality|In Hatches 1:100 000 Sheet area, from GR 163810, in the central part of the dome, north of GR 164835 (8.7 km SSW of the Pioneer mine, latitude 20o52'10"S, longitude 135o11'00"E), where the formation is overlain by Unimbra Sandstone. The main rock types of the formation are exposed in this section.|16-MAY-23
26313|Mia Mia Volcanics|Extent|Confined to central part of a large structural dome in the southwest of the Hatches 1:100 0000 Sheet area and extending south into the Elkedra 1:100 0000 Sheet area (Elkedra 1:250 000 Sheet area); crops out over about 60 km2.|16-MAY-23
26313|Mia Mia Volcanics|Thickness range|Probably at least 2000 m.|16-MAY-23
26313|Mia Mia Volcanics|Lithology|Moderately recessive massive ignimbritic felsic tuff, bedded tuff, and rhyolitic lava, and interlayered partly ridge-forming, variably feldspathic/volcaniclastic quartz arenite, and rare volcaniclastic conglomerate. The volcanic rocks are commonly cleaved.|16-MAY-23
26313|Mia Mia Volcanics|Relationships and boundaries|Base and underlying rocks not exposed; overlain conformably, or possibly disconformably, by Unimbra Sandstone - arenite beds near the top of the Mia Mia Volcanics are concordant with those of the overlying Unimbra Sandstone. Intruded by unnamed granite and pegmatite.|16-MAY-23
26313|Mia Mia Volcanics|Age reasons|Younger than 1870 m.y. - U-Pb zircon age for volcanics within the Warramunga Group overlain unconformably by the Hatches Creek Group. Older than 1640 m.y. - Rb-Sr whole-rock age of granite intruding the Hatches Creek Group.|16-MAY-23
26313|Mia Mia Volcanics|Defn author|Blake D.H., Stewart A.J., Sweet I.P., Wyche S., 1985|16-MAY-23
26313|Mia Mia Volcanics|Proposed publication|BMR Report 257|16-MAY-23
26313|Mia Mia Volcanics|Comments|Remarks: Differs from geographically separated but stratigraphically partly equivalent Treasure Volcanics exposed to the north in consisting mainly of felsic tuffs, rather than lava flows. Part of the Ooradidgee Subgroup of the Lower Hatches Creek Group.|16-MAY-23
26313|Mia Mia Volcanics|Defn Reference|86/25362|16-MAY-23
26313|Mia Mia Volcanics|Proposer|Blake D.H.|16-MAY-23
26313|Mia Mia Volcanics|Resdate|07-OCT-1981|16-MAY-23
22337|Milyakburra Formation|Name source|Milyakburra community (GR PE290760), on Bickerton Island, BLUE MUD BAY.|16-MAY-23
22337|Milyakburra Formation|Unit history|Formerly mapped as part of the now abandoned 'Groote Eylandt beds' (Plumb and Roberts, 1965,1992).|16-MAY-23
22337|Milyakburra Formation|Geomorphic expression|Prominent joint-controlled, bare rocky outcrops, commonly forming domal or mesa-like rocky ridges.|16-MAY-23
22337|Milyakburra Formation|Type section locality|Lower boundary stratotype: Eastern side of South Bay (lat. 13o 48' 30"S, long. 136o 12'E; GR PE297735). Reference section: South of Milyakburra community, on eastern side of Bickerton Island (lat. 13o 48'S, long. 136o 12'E; GR PE295740).|16-MAY-23
22337|Milyakburra Formation|Extent|Bickerton Island, BLUE MUD BAY.|16-MAY-23
22337|Milyakburra Formation|Thickness range|A maximum thickness of 40m exposed in incomplete sections.|16-MAY-23
22337|Milyakburra Formation|Lithology|Matrix- to clast-supported, polymict, coarse sand- to granule-matrix cobble and boulder conglomerate which is massive to cross-bedded; locally interbedded with granule conglomerate and medium- to very coarse-grained lithic sandstone.|16-MAY-23
22337|Milyakburra Formation|Depositional environment|High-energy fluvial and alluvial fan environment. The facies probably represent a mixture of debris flow, talus and channel-base deposits.|16-MAY-23
22337|Milyakburra Formation|Relationships and boundaries|Erosional contact with underlying Bickerton Rhyolite and Abarungkwa Sandstone. No contact with overlying units is exposed.|16-MAY-23
22337|Milyakburra Formation|Age reasons|Probably Orosirian (Palaeoproterozoic). The underlying Bickerton Rhyolite has been dated by SHRIMP single-zircon U-Pb techniques at ~1815 Ma (Pietsch et al. 1994).|16-MAY-23
22337|Milyakburra Formation|Correlations|Considered to correlate with the ~1800-1840 Ma felsic volcanic suite widespread in northern Australia (Rawlings, 1994).|16-MAY-23
34025|Milyema Formation|Name source|Milyema Island (GR PE720872), north of Groote Eylandt in PORT LANGDON.|16-MAY-23
34025|Milyema Formation|Unit history|Formerly mapped as part of the now abandoned 'Groote Eylandt beds' (Plumb and Roberts, 1965, 1992).|16-MAY-23
34025|Milyema Formation|Geomorphic expression|Prominent rugged, joint-controlled, bare rocky outcrops.|16-MAY-23
34025|Milyema Formation|Type section locality|Upper boundary stratotype: North coast of Chasm Island, lat. 13o 39' 30"S, long. 136o 35'E (GR PE715898); includes 50m of upper part of formation. Upper boundary reference locality: Jagged Head (lat 13o 42'S, long. 136o 45'E, GR PE890852).|16-MAY-23
34025|Milyema Formation|Extent|Northern extremities of Groote Eylandt, including Chasm Island, Jagged Head and adjacent small islands, BLUE MUD BAY.|16-MAY-23
34025|Milyema Formation|Thickness range|Exposed thickness of 50m at boundary stratotype, probably significantly greater at some other localities.|16-MAY-23
34025|Milyema Formation|Lithology|Polymict basal granule to boulder conglomerate and interbedded coarse-grained pebbly lithic sandstone; pink, predominantly medium-grained sandstone with minor granule lenses.|16-MAY-23
34025|Milyema Formation|Depositional environment|Lower units deposited in high-energy braided fluviatile and probably low-gradient alluvial fan-edge environments. Upper unit partly fluviatile and possibly shallow marine.|16-MAY-23
34025|Milyema Formation|Relationships and boundaries|Base not exposed, but abundance of porphyritic rhyolite and Grindall Formation clast in lowest beds indicates close vertical or lateral proximity of these units. The upper contact with the overlying Alyinga Sandstone is erosional, but not angular.|16-MAY-23
34025|Milyema Formation|Age reasons|Probably Orosirian (Palaeoproterozoic). The underlying Bickerton Rhyolite has been dated by SHRIMP single-zircon U-Pb techniques at ~1815 (Pietsch et al, 1994).|16-MAY-23
34025|Milyema Formation|Correlations|Considered to correlate with the ~1800-1840Ma felsic volcanic suite widespread in northern Australia (Rawlings, 1994).|16-MAY-23
84103|Mingabarri Formation|Name source|Unit named derived from the Mingabarri Range, an elevated geographical feature present in the northwestern MOUNT DRUMMOND and southwestern CALVERT HILLS 1:250 000 mapsheets in the Northern Territory.|
84103|Mingabarri Formation|Unit history|Unit was originally mapped as the “Mullera Formation” on the First Edition MOUNT DRUMMOND 1:250 000 mapsheet (Smith and Roberts, 1963a, b). The unit was subsequently remapped as the “Crow Formation” by Rawlings et al (2006, 2008).|
84103|Mingabarri Formation|Geomorphic expression|The Mingabarri Formation outcrops very well due to its steep dips and the incision of the Canyon Range area (Rawlings et al, 2008), and forms the bulk of the Mingabarri Range topographic high in the northwestern MOUNT DRUMMOND 1:250 000 mapsheet area.|
84103|Mingabarri Formation|Type section locality|There is no type locality nominated for this formation. A reference area is nominated in the northwestern MOUNT DRUMMOND 1:250 000 mapsheet, in the vicinity of (GDA94) 18°11’10”S 136°51’45”E (53K 696989mE 7988224mN).|
84103|Mingabarri Formation|Extent|The Mingabarri Formation outcrops in the Mingabarri Range area in the northwestern MOUNT DRUMMOND and southwestern CALVERT HILLS 1:250 000 mapsheets in the Northern Territory.|
84103|Mingabarri Formation|Thickness range|Including the thickness of the Boxer Member, the Mingabarri Formation ranges in thickness from approximately 1500 m to 2200 m. However this estimate may include some structural repetition (Rawlings et al, 2008).|
84103|Mingabarri Formation|Lithology|In the reference area, the Mingabarri Formation is represented by an overall coarsening-upward succession, with the following sedimentary facies interdigitating throughout the succession: “Saprolite facies”: surficial weathering of carbonaceous and/or pyritic shale, resulting in knobbly, massive ferruginous chert, silcrete and calcareous clayey saprolite. “Deep shelf facies”: Fissile to flaggy white clayey siltstone and fine-grained lithic micaceous sandstone, red-brown to grey shale and leached, chalky white or maroon, mottled porcellaneous claystone. “Storm shelf facies”: Flaggy white, fawn, red-brown or purple micaceous siltstone and fine- to medium-grained quartzose to sublithic (±micaceous) sandstone. “Debris flow facies”: Red-brown, orange, pink, white or yellow, poorly sorted, feldspathic, micaceous, ferruginous and lithic, medium- to very coarse-grained sandstone, pebbly sandstone and lesser matrix-supported conglomerate. “Sandstone turbidite facies”: White to grey, silicified, fine- to coarse-grained, sublithic to lithic sandstone with locally abundant, rounded pebble (plus rare cobble) trails. “Shallow water sandstone facies”: Thick units of white to red-brown or maroon, silicified, fine- to very coarse-grained quartzose to lithic sandstone, with locally abundant rounded pebble trails and localised, poorly sorted, pebble-cobble conglomerate(Rawlings et al, 2008).|
84103|Mingabarri Formation|Depositional environment|The Mingabarri Formation appears to comprise a variety of depositional environments from deep water (characterised by saprolite facies [after shale], deep-shelf facies, storm-shelf facies, sandstone turbidite facies, and debris-flow facies) to shallow water (characterised by shallow-water sandstone facies) (Rawlings et al, 2008).|
84103|Mingabarri Formation|Relationships and boundaries|The Mingabarri Formation either locally conformably overlies the Bowgan Sandstone or unconformably overlies the Buddycurrawa Volcanics, and is conformably overlain in turn by the Creswell Creek Sandstone.|
84103|Mingabarri Formation|Identifying features|The Mingabarri Formation appears distinct in outcrop due to the presence of prolific debris flows, comprised of medium- to very coarse-grained sandstone, pebbly sandstone, and lesser matrix-supported conglomerate (Rawlings et al, 2008).|
84103|Mingabarri Formation|Structure and Metamorphism|There may be some structural repetition of the Mingabarri Formation proximal to the Benmara Fault.|
84103|Mingabarri Formation|Age reasons|Maximum depositional ages derived from U-Pb SHRIMP dating of detrital zircons: Creswell Creek Formation (stratigraphically overlies Mingabarri Formation): GA sample 3305198 - 1625 ± 27 Ma (Kositcin et al, 2020). Mingabarri Formation: GA Sample 2785621 – 1649 ± 19 Ma (Kositcin and Carson, 2019). Bowgan Sandstone (stratigraphically underlies Mingabarri Formation): GA sample 2785620 – 1652 ± 10 Ma (Kositcin and Carson, 2019). Therefore, the potential depositional age range for the Mingabarri Formation can be considered to extend from ca. 1649 ± 19 Ma to 1625 ± 27 Ma.|
84103|Mingabarri Formation|Correlations|The Mingabarri Formation, based on its maximum depositional age estimate and those of the underlying and overlying formations, can be correlated with the ungrouped Caulfield Formation and several formations of the McNamara Group, including the Shady Bore Quartzite, the Bullrush Conglomerate, and the Plain Creek Formation (Kositcin and Carson, 2019). The Mingabarri Formation may be correlative with components of the upper Glyde to lowermost Favenc packages (Rawlings, 1999) of the McArthur Basin.|
84103|Mingabarri Formation|Alteration and Mineralisation|The lowermost sections of the Mingabarri Formation have been altered to saprolite in some areas. Some intervals of the Mingabarri Formation show silicification.|
84103|Mingabarri Formation|Geophysical Expression|Weak to moderate magnetic response.|
84103|Mingabarri Formation|Defn author|Elliot Foley, Jack Simmons, Ben Williams, Charles Verdel (Northern Territory Geological Survey), Chris Carson (Geoscience Australia) 31-MAY-2023.|
84103|Mingabarri Formation|Comments|Note: Standard series 1: 100 000 and 1: 250 000 mapsheet names are shown in uppercase.|
84103|Mingabarri Formation|References|Carson, C. J., Kositcin, N., Anderson, J. R., and Henson, P. A. in prep. A revised Proterozoic tectono-stratigraphy of the South Nicholson region, Northern Territory, Australia - insights from SHRIMP U-Pb detrital zircon geochronology. Australian Journal of Earth Sciences. 
 **Kositcin N and Carson CJ, 2019. New SHRIMP U-Pb zircon ages from the South Nicholson and Carrara Range regions, Northern Territory. Geoscience Australia, Record 2019/09.  **Kositcin N, Carson CJ, Anderson JR, Doublier MP and Murr J, 2020. Exploring for the Future - New SHRIMP geochronology constraints on the basin evolution of the South Nicholson region. Geoscience Australia, Record 2020/025.  **Rawlings DJ, 1999. Stratigraphic resolution of a multiphase intracratonic basin system: the McArthur Basin, northern Australia. Australian Journal of Earth Sciences 46(5), 703–723.  **Rawlings DJ, Sweet IP and Kruse PD, 2006. Mount Drummond, NT (Second Edition). 1:250 000 Geological Map, Sheet SE 53-12. Northern Territory Geological Survey, Darwin, Northern Territory.  **Rawlings DJ, Sweet IP and Kruse PD, 2008. Mount Drummond, NT (Second Edition). 1:250 000 Geological Map Series Explanatory Notes, Sheet SE 53-12. Northern Territory Geological Survey, Darwin, Northern Territory.  **Simmons JM, Williams B, Carson, C and Verdel C, 2023a. Mount Drummond, Northern Territory 1:250 000 Geological Map, Sheet SE 53-12 (Third Edition). Northern Territory Geological Survey, Darwin, Northern Territory.  **Simmons JM, Williams B, Carson, C and Verdel C, 2023b. Mount Drummond, Northern Territory 1:250 000 Geological Map Explanatory Notes, Sheet SE 53-12 (Third Edition). Northern Territory Geological Survey, Darwin, Northern Territory.  **Smith JW and Roberts HG, 1963a. Mount Drummond, NT (First Edition). 1:250 000 Geological Map Series Explanatory Notes, Sheet 53-12. Bureau of Mineral Resources, Canberra.  **Smith JW and Roberts HG, 1963b. Mount Drummond, NT (First Edition). 1:250 000 Geological Map Series, Sheet SE 53-12. Bureau of Mineral Resources, Canberra.|
11983|Mitchiebo Volcanics|Name source|From the Mitchiebo 1:100 000 Sheet area (Sheet 6360), Northern Territory, which contains the westernmost outcrops of the formation.|16-MAY-23
11983|Mitchiebo Volcanics|Unit history|Formerly an unnamed volcanic member within the Carrara Range Formation (now a Group) of Smith & Roberts (1963).|16-MAY-23
11983|Mitchiebo Volcanics|Type section locality|The section extends from GR 835301 (base) to 853313 (top), and is about 900 m thick.|16-MAY-23
11983|Mitchiebo Volcanics|Extent|An arcuate belt east of Mount Drummond, in the Carrara 1:100 000 Sheet area, and scattered minor outcrops in eastern Mitchiebo; total outcrop about 50 km2.|16-MAY-23
11983|Mitchiebo Volcanics|Lithology|Weathered vesicular and amygdaloidal basalt or trachyte, particularly in the lower half of the formation. Upper part is mainly quartzose and lithic sandstone with thin volcanic interbeds.|16-MAY-23
11983|Mitchiebo Volcanics|Relationships and boundaries|The Mitchiebo Volcanics conformably overlie the Don Creek Sandstone. The contact is marked by a prominent lithological change from quartz sandstone to basic volcanics. The Volcanics are overlain disconformably by the Top Rocky Rhyolite.|16-MAY-23
11983|Mitchiebo Volcanics|Age reasons|Proterozoic, Carpentarian - correlated with sequences of known Carpentarian age by Plumb & Derrick (1975) and Hutton & Sweet (1982, in press).|16-MAY-23
11983|Mitchiebo Volcanics|Proposed publication|BMR Report 242|16-MAY-23
11983|Mitchiebo Volcanics|Defn approved by|Brakel A.T. (subject to Hutton & Sweet details being entered when published)|16-MAY-23
11983|Mitchiebo Volcanics|Defn Reference|83/23538|16-MAY-23
11983|Mitchiebo Volcanics|First Reference|82/12103 Fig. 3|16-MAY-23
11983|Mitchiebo Volcanics|Proposer|Sweet I.|16-MAY-23
11983|Mitchiebo Volcanics|Resdate|07-JAN-1980|16-MAY-23
11995|Mittiebah Sandstone|Type section locality|easting / northing  from 53 688100 / 7916100 to 53 689400 / 7908850. Near -18°52' 136°47'. Central Mittiebah Range in MOUNT DRUMMOND. Note: top of formation not exposed.|16-MAY-23
11995|Mittiebah Sandstone|Defn author|TS in Rawlings et al 2008. Drummond 1:250 000 sheet explanatory notes.|16-MAY-23
81819|Molyhil Suite|Name source|After Molyhil tungsten-molybdenum deposit in central JINKA 1:100 000 mapsheet, Northern Territory (135.7503degreesE 22.7589dgreesS (GDA2020)).|16-MAY-23
81819|Molyhil Suite|Constituents|Dinkum Orthogneiss, Narbarloo Granite, Double Dam Granite, Mascotte Orthogneiss.|16-MAY-23
81819|Molyhil Suite|Geomorphic expression|Low and prominent hills and ranges; isolated rises and boulder fields.|16-MAY-23
81819|Molyhil Suite|Type section locality|There is no single locality where all constituent units are exposed. See definition cards for descriptions of constituent units.|16-MAY-23
81819|Molyhil Suite|Extent|Constituent units outcrop throughout southern HUCKITTA 1:250 000 mapsheet (Weisheit et al in prep), north of and within the Delny Shear Zone and south of the Georgina Basin: in the Bonya Hills, south and west of the Elua Range, and around the Mopunga Range area east of Little Frazer Creek (between ~135.1847-136.1207degreesE and ~22.5434-22.8377degreesS (GDA2020)).|16-MAY-23
81819|Molyhil Suite|General description|Constituent units are uniformly granitic mica-bearing orthogneisses. All constituent units are deformed by a regional main foliation. Locally contains xenoliths of Bonya and Deep Bore metamorphics and Kings Legend Metadolerite. Intruded by Samarkand Pegmatite and rocks of the Sainthill Suite. Locally unconformably overlain by Neoproterozoic Oorabra Arkose and Grant Bluff Formation of the Georgina Basin; locally faulted contacts with various units of the Georgina Basin.|16-MAY-23
81819|Molyhil Suite|Depositional environment|Genesis: Continental margin environment, either arc cordillera or back arc basin, or derived from melting of pre-existing crust that formed in a continental margin environment.|16-MAY-23
81819|Molyhil Suite|Identifying features|Constituent units are uniformly mica-bearing foliated granites and granitic orthogneisses. All constituent units are deformed by a regional main foliation.|16-MAY-23
81819|Molyhil Suite|Structure and Metamorphism|All constituent units are overprinted by the regional main foliation ranging from weakly to strongly foliated and locally gneissic; locally overprinted by mylonitic foliation along and adjacent to regional-scale fault zones; all constituent units deformed during regional high-thermal gradient amphibolite- to granulite-facies metamorphism; Dinkum Orthogneiss is commonly migmatitic.|16-MAY-23
81819|Molyhil Suite|Age reasons|Three units of the suite have known crystallisation ages: Dinkum Orthogneiss LA-ICP-MS 207Pb/206Pb zircon age of 1793 +/- 4 Ma (Beyer et al in review), Narbarloo Granite SHRIMP 207Pb/206Pb zircon age of 1792 +/- 3 Ma (Kositcin et al 2021), Mascotte Orthogneiss SHRIMP 207Pb/206Pb zircon age of 1789 +/- 3 Ma (Kositcin et al 2011).|16-MAY-23
81819|Molyhil Suite|Correlations|Interpreted as co-magmatic and co-genetic with the Casper Suite and Fosters Suite of the Baikal Supersuite based on similar geochemical and isotopic composition, and timing of structural fabric development.|16-MAY-23
81819|Molyhil Suite|Alteration and Mineralisation|Local K-feldspar-quartz alteration, hematitisation, and silicification; quartz and calcite veining is common close to shear zones. Locally mineralised by epigenetic Cu-W mineralisation (Bonya deposit; McGloin and Weisheit 2021).|16-MAY-23
81819|Molyhil Suite|Geophysical Expression|When extensive enough, the constituent units are characterised by magnetic high responses; no clear gravity response; radiometric high response.|16-MAY-23
81819|Molyhil Suite|Geochemistry|I-type intrusive rocks; metaluminous to weakly-strongly peraluminous (possibly due to secondary processes), high-K (calc-alkaline) to shoshonitic compositions, strongly to moderately enriched in LREE compared to HREE, strong to moderate negative Eu anomalies and rare positive Eu anomalies, evolved Nd isotopic signatures. Indicating fractional crystallisation and crustal contamination.|16-MAY-23
81819|Molyhil Suite|Defn author|Anett Weisheit, Barry Reno, Eloise Beyer, Pablo Farias (NT Department of Industry, Tourism and Trade, Northern Territory Geological Survey) 3-May-2022.|16-MAY-23
81819|Molyhil Suite|References|Beyer EE, Whelan JA, Reno BL, Weisheit A, Thompson JM, Meffre S, Huang H, Woodhead JD, Fanning M and Armstrong R, 2022. Summary of results. NTGS laser ablation ICP-MS U-Pb-Hf geochronology project: selected samples from HUCKITTA 1:250 000 mapsheet, May 2011?October 2018. Northern Territory Geological Survey, Record 2022-007.  **Kositcin N, Magee CW, Whelan JA and Champion DC, 2011. New SHRIMP geochronology from the Arunta Region: 2009-2010. Geoscience Australia, Record 2011-014.  **McGloin MV and Weisheit A, 2021. Epigenetic copper and tungsten mineralisation in JINKA and JERVOIS RANGE, northeastern Aileron Province. Northern Territory Geological Survey, Record.   **Weisheit A et al, in prep. Huckitta, Northern Territory (Third Edition). 1:250 000 geological map series explanatory notes, SF53-11. Northern Territory Geological Survey, Darwin.|16-MAY-23
12130|Montejinni Limestone|Name source|Named for 'Montejinni' Homestead (lat. 16o39'S, Long. 131o46'E on Victoria River Downs), near which the limestone is exposed in hills 7-10m high.|16-MAY-23
12130|Montejinni Limestone|Unit history|Chewings (1931) included the formation int eh Winnecke Creek Tableland formation. Previously mapped as Gum Ridge Formation by Milligan and others (1966), Brown & Randal (1969), Randal & Brown (1969), Mendum & Tonkin (1976) and Dodson & Gardener (1978) in the eastern Wiso Basin; the Gum Ridge Formation is now restricted to the Georgina Basin. Montejinni limestone of Schmidt and others (1976); Montejinni formation of Twidale (1984).|16-MAY-23
12130|Montejinni Limestone|Type section locality|Base (boundary stratotype) exposed in a partial section at 'Montejinni' homestead (lat. 16o39'S, long. 131o46'E on Victoria River Downs; Traves, 1955), at base of 7-10m-high limestone hills resting unconformably on Antrim Plateau Volcanics (Lower Cambrian). Reference section: Top (boundary stratotype) at 185.9m depth in a near-complete section in BMR drillhole Green Swamp Well 6 (Green Swamp Well; Kennewell & Huleatt, 1980; lat 19o20', long. 132o59'E), at top of grey-buff dolostone. Boundary coincides with defined base of conformably overlying Hooker Creek Formation. Cores and cuttings stored at BMR Core and Cuttings Laboratory, Fyshwick ACT.|16-MAY-23
12130|Montejinni Limestone|Extent|Throughout Wiso Basin. Outcrop in DELEMERE, VICTORIA RIVER DOWNS, DALY WATERS, WAVE HILL, BEETALOO, BIRRINDUDU*, WINNECKE CREEK, SOUTH LAKE WOODS, HELEN SPRINGS, TANAMI*, TANAMI EAST*, GREEN SWAMP WELL*, TENNANT CREEK, MOUNT SOLITARE* (*as undifferentiated Montejinni Limestone and Hooker Creek Formation only). Subcrop proven or inferred in LARRIMAH, NEWCASTEL WATERS, LANDER RIVER, BONNEY WELL.|16-MAY-23
12130|Montejinni Limestone|Thickness range|Maximum 151.2m+ in a near-complete section in BMR drillhole Green Swamp Well 6 (Kennewell & Huleatt, 1980).|16-MAY-23
12130|Montejinni Limestone|Lithology|Grey limestone and dolostone (laminated, stylolitic, mottled, bioclastic, onkoid, ribbon, may include nodular chert); yellow-grey cryptalgal laminite; grey calcareous mudstone; maroon siltstone. Nodular evaporites in several lithotypes. In places, basal breccia of reworked clasts in dolomitic matrix. At surface: grey chert and quartzite, tabular brown chert, silicified bioclastic coquina, silicified nodular evaporite.|16-MAY-23
12130|Montejinni Limestone|Fossils|Fauna includes trilobites Redlichia and Xystridura, hyoliths, inarticulate (including acrothelid) and orthide brachiopods, echinoderm plates, sponge spicules, chancelloriides, molluscs and problematic tubes.|16-MAY-23
12130|Montejinni Limestone|Relationships and boundaries|Unconformably overlies Antrim Plateau Volcanics or its equivalents (Lower Cambrian), or where this is absent, various Proterozoic units. Basal beds are limestone, or breccia of reworked clasts in carbonate-bearing matrix. Conformably overlain by Hooker Creek Formation, or where this is absent, unconformably overlain by Point Wakefield beds (Templetonian, Middle Cambrian) in eastern Wiso Basin. Boundary with Hooker Creek Formation is a contact between grey dolostone below and maroon siltstone above.|16-MAY-23
12130|Montejinni Limestone|Age reasons|Redlichia together with Xystridura indicates an Ordian (early Middle Cambrian) age (Traves, 1955; Milligan and other, 1966; Randal & Brown, 1967; Randal, 1973).|16-MAY-23
12130|Montejinni Limestone|Defn author|Kruse, P.D., after Traves (1955), 1992.|16-MAY-23
12130|Montejinni Limestone|References|Brown, M.C., Randal, M.A. 1969. 1:250 000 geological series explanatory notes, Beetaloo, NT. Bureau of Mineral Resources, Australia. **Chewings, C., 1931. A deliniation of the Precambrain plateau in central and north Australia with notes on the impingent sedimentary formations. Transactions, Royal Society of South Australia 55, 1-11. **Dodson, R.G., Gardner, J.E.F., 1978. 1:250 000 geological series explanatory notes, Tennant Creek, Northern Territory. Bureau of Mineral Resources, Australia. **Kennewell, P.J., Huleatt, M.B., 1980. Geology of the Wiso Basin, Northern Territory. Bureau of Mineral Resources, Australia, Bulletin 205. **Mendum, J.R., Tonkin, P.C., 1976. Geology of Tennant Creek 1:250 000 sheet area, Northern Territory. Bureau of Mineral Resources, Australia, Record 1976/68 (unpublished). **Milligan, E.N., Smith, K.G., Nichols, R.A.H., Doutch, H.F., 1966. Geology of the Wiso Basin, Northern Territory.  Bureau of Mineral Resources, Australia, Record 1966/47 (unpublished). **Randal, M.A., 1973. Groundwater in the northern Wiso Basin, Northern Territory. Bureau of Mineral Resources, Australia, Bulletin 123. **Randal, M.A., Brown, M.C., 1967. The geology of the northern part of the Wiso Basin, Northern Territory. Bureau of Mineral Resources, Australia, Record 1967/110 (unpublished). **Randal, M.A., Brown, M.C., 1969. 1:250 000 geological explanatory notes, Helen Springs, N.T. Bureau of Mineral Resources, Australia. **Schmidt, p.w., Currey, D.T., Ollier, C.D., 1976. Sub-basaltic weathering, damsites, palaeo-magnetism, and the age of laterization. Journal of the Geological Society of Australia 23, 367-370. **Traves, D.M., 1955. The geology of the Ord-Victoria region, Northern Territory. Bureau of Mineral Resources, Australia, Bulletin 27. **Twidale, C.R., 1984. The enigma of the Tindal Plain, Northern Territory. Transactions, Royal Society of South Australia 108, 95-103.|16-MAY-23
25731|Mordor Igneous Complex|Name source|Mordor Pound (GR 5751-440090) in which the Complex crops out, Laughlen 1:100 000 Sheet area.|16-MAY-23
25731|Mordor Igneous Complex|Unit history|The name Mordor Complex has been used by Langworthy & Black (1978), but Mordor Igneous Complex is preferred because it has been used previously by Stewart & Warren (1977) and Warren (1978). The title 'Igneous Complex' also helps to differentiate it from various metamorphic complexes in the same area.|16-MAY-23
25731|Mordor Igneous Complex|Type section locality|Reference area: The most unusual rock type in the complex is a phlogopite-rich peridotite and this is well exposed at a conical hill at GR 465069 in the Laughlen 1:100 000 Sheet area. The best exposures of the various rock types may be observed near the north/south traverse base line graded by CRA from GR 472052 476091.|16-MAY-23
25731|Mordor Igneous Complex|Extent|The Complex crops out over 36 km2 inside Mordor Pound, a region of low relief surrounded by sheer cliffs of Heavitree Quartzite.|16-MAY-23
25731|Mordor Igneous Complex|Lithology|The Complex consists of ultrabasic to intermediate igneous rocks unusually enriched in larage ion lithophile elements such as Ba, Rb, Sr, and K. These were unusually abundant in the primary magma, and led to derivatives enriched in phlogopite, hyalophane, and Ba orthoclase, such as phlogopite-peridotite, pyroxenite, shonkinite, melamonzonite, monzonite, syenite, and pegmatite. Carbonate veins associated with the Complex appear to be of secondary origin, by leaching and precipitation from groundwater, not of carbonate origin. Further details are given by Langworthy & Black (1978).|16-MAY-23
25731|Mordor Igneous Complex|Relationships and boundaries|Intrudes the Jennings Granitic Gneiss.|16-MAY-23
25731|Mordor Igneous Complex|Age reasons|Late Proterozoic. 1210 +/- 90 m.y. by Rb-Sr dating on whole-rocks and minerals (Langworthy & Black, 1978).|16-MAY-23
25731|Mordor Igneous Complex|Proposed publication|Stewart & others 1980|16-MAY-23
25731|Mordor Igneous Complex|Defn approved by|Branch C.T., Brown M (per V. Passmore)|16-MAY-23
25731|Mordor Igneous Complex|Defn Reference|80/20787|16-MAY-23
25731|Mordor Igneous Complex|Name first published by|Stewart A.J., Warren R.G., 1977|16-MAY-23
25731|Mordor Igneous Complex|Status|1|16-MAY-23
12356|Morphett Creek Formation|Name source|Morphett Creek in the Helen Springs 1:250 000 Sheet area, latitute 18o53'S, longitude 134o05'E.|16-MAY-23
12356|Morphett Creek Formation|Type section locality|Between GRs 407893 and 403891 in the Tennant Creek 1:250 000 Sheet area. A generalised section has at its base 16 m of ferruginous quartz sandstone with jasperoidal cement. This is overlain by 60 m of flaggy to blocky feldspathic quartz sandstone, with ripple marks, mudclasts and cross-bedding. On this rests a lens of boulder conglomerate up to 14 m thick; boulders are of orthoquartzite, quartz and pebbly sandstone. The sandstone and conglomerate are succeeded by 220 m of interbedded red and white shale and micaceous siltstone, some quartz siltstone and feldspathic quartz sandstone, in generaly flaggy to laminated. Minor ironstone and calcareous beds are intercalated in this sequence at intervals, typically of aboaut 15 to 25 m.|16-MAY-23
12356|Morphett Creek Formation|Extent|This formation of easily eroded soft shale and siltstone, has only limited outcrop, in the central part of the Whittington Range and in some areas on the northern side of the Short Range.|16-MAY-23
12356|Morphett Creek Formation|Thickness range|From 2500 to 4800 m.|16-MAY-23
12356|Morphett Creek Formation|Lithology|The lower part of the formation consists of fissile to floggy, and locally massive and thick-bedded, feldspathic sandstone with thin conglomerate locally above it and several bands of rounded quartz pebbles near the base. Ripple marks, cross-beds and shale clasts are common. This is overlain by floggy to laminated shale and siltstone, with minor interbedded quartz siltstone and feldspathic quartz sandstone. The lower 100 to 150 m of the feldspathic sandstone is ferruginous and has a jasperoidal cementing material. The rock has a deep brown colour and is readily recognised on airphotos as a dark horizon immediately overlying the Whittington Range Volcanics. The siltstone and shale are soft and poorly exposead.|16-MAY-23
12356|Morphett Creek Formation|Relationships and boundaries|Conformably overlies the Whittington Range Volcanics and is conformably overlain by the Short Range Sandstone.|16-MAY-23
12356|Morphett Creek Formation|Age reasons|By assumed correlation of Tomkinson Creek Beds with Hatches Creek Group, late Early Proterozoic to Early Carpentarian.|16-MAY-23
12356|Morphett Creek Formation|Proposed publication|See refereances under Mendum and Tonkin; Dodson and Gardener.|16-MAY-23
12356|Morphett Creek Formation|Name first published by|Stewart A.J., Langworthy A.P., Warren R.G., Offe L.A., Glikson A.Y., Wells A.T., Le Messurier P., Gardener J.E.F., 1976|16-MAY-23
24389|Mount Airy Orthogneiss|Name source|Mount Airy (301800E, 7512200N) in Reynolds Range, SW part of Tea Tree 1:100 000 Sheet area, is situated 1 km due S of the SE-most outcrop of Mount Airy Orthogneiss. Mount Airy itself is composed of metamorphosed Pine Hill Formation (metapelitic granulite).|16-MAY-23
24389|Mount Airy Orthogneiss|Type section locality|Point 292000E, 7521000N, in Warimbi Hills, 7.5 km SW of Pine Hill H.S., ion SE part of Reynolds Range 1:100 000 Sheet area. Hilly terrain of augen granite, foliated NW, cut by second 'strain-slip' foliation N/S; dykes of microgranite contain xenoliths of augen granite.|16-MAY-23
24389|Mount Airy Orthogneiss|Extent|Between Reynolds and Anmatjira Ranges in SE part of Reynolds Range 1:100 000 Sheet and SW part of Tea Tree 1:100 000 Sheet areas.|16-MAY-23
24389|Mount Airy Orthogneiss|Lithology|Coarse foliated augen granite, grading to massive porphyritic granite in placeas. Some tourmnaline closts. An elongate irregular body of porphyritic microgranite between SW margin of Mt Airy Orthogneiss (Pgr) and Lander Rock beds and Mt Thomas Quartzite is interpreted as a chilled border phase of the Mount Airy Orthogneiss and labelled Pgr1 - an unnamed member of the Mount Airy Orthogneiss.|16-MAY-23
24389|Mount Airy Orthogneiss|Relationships and boundaries|Intrudes Lander Rock beds, adjoins and deforms Mount Thomas Quartzite, but latter is not actually breached by Mt Airy Orthogneiss. Is faulted against Yaningidjara Orthogneiss and Weldon metamorphics (q.v.). Intruded by dykes of aplite, metabasic rock, and by quartz veins and dykes of microgranite. Adjoins and probably intruded by Harverson Granite (q.v.), as latter is not intruded by basic dykes.|16-MAY-23
24389|Mount Airy Orthogneiss|Identifying features|Reason for proposed name: a large and distinctive body of granite, and different in mineralogy and texture from other nearby or adjoining granites.|16-MAY-23
24389|Mount Airy Orthogneiss|Age reasons|Not isotopically dated. Younger than Lander Rock beds and Mount Thomas Quartzite (Early Proterozoic or older). Probably same age as neighbouring Napperby Gneiss on S. side of Reynolds Range, and hence probably late Early or early Middle Proterozoic.|16-MAY-23
24389|Mount Airy Orthogneiss|Proposed publication|1. 'Geology of NW Arunta Block' - BMR Publication.  2. 'Stratigraphic definitions in Arunta Block' - BMR Microfiche Report.|16-MAY-23
24389|Mount Airy Orthogneiss|Defn Reference|80/20787|16-MAY-23
24389|Mount Airy Orthogneiss|Proposer|Stewart A.J.|16-MAY-23
24389|Mount Airy Orthogneiss|Reserved? Yes/No|Yes|16-MAY-23
12476|Mount Baldwin Formation|Name source|Smith  (1964) says name taken from Mount Baldwin, latitute 22deg 49' S, Longitude 135deg 57'40" E.|16-MAY-23
12476|Mount Baldwin Formation|Type section locality|Type section of Smith (1964) X4 is in the Elyuah Range at 22deg 45'30" S, 135deg 53'10" E.|16-MAY-23
12476|Mount Baldwin Formation|General description|The Mount Baldwin Formation of Smith (1964) is here redefined to exclude the archaeocyathan dolomite and overlying rocks in the type section and elsewhere. It is also noted that the upper sandstone in the type section of the Mount Baldwin Formation as defined by Smith (1964) is a fault repetition of the Mount Baldwin Formation sensu stricto. In many parts of the Huckitta 1:250 000 Sheet area the Elkera Formation (former upper Grant Bluff Formation) has been mis-mapped as Mount Baldwin Formation. Smith's (1964) type section X4 is retained; this is section 13 of Walter (1979). In this section the formation is 280 m thick. Its base is defined as the base of the yellow-green pebbly sandstone overlying the light grey sandstone of the Elkera Formation. This seems to be the same position selected by Smith (1964). The top of the formation is placed at the base of the archaeocyathan dolomites above the ridge-forming sandstones of the formation.|16-MAY-23
26755|Mount Bleechmore Granulite|Name source|After Mount Bleechmore (GR 4235E, 74722N, AMG - metric) within outcrop area, Alcoota 1:250 000 Sheet area SF.53-10, Australian Map Grid.|16-MAY-23
26755|Mount Bleechmore Granulite|Type section locality|For 2 km along unnamed creek bed east of Mount Bleechmore centred at 427E, 7471N, AMG - metric). Plutonic migmatite unit (pCeg) not in type section; best exposed at GR 439E, 7478N.|16-MAY-23
26755|Mount Bleechmore Granulite|Extent|Outcrops occur in the Mount Bleechmore area between Musty Well ( GR 415E, 7476ON) and Alcoota homestead (GR 444E, 7476N, AMG - metric).|16-MAY-23
26755|Mount Bleechmore Granulite|Lithology|pCe-Sillimanite-garnet-biotite-feldspar-quartz gneiss, garnet-potassium feldspar-quartz migmatite; minor mafic granulite, calcareous pelitic gneiss, calc-silicate rock and plutonic migmatite. pCeg - west and southwest of Alcoota homestead - plutonic garnet-bearing migmatite, considered similar to the Mount Swan Granite but in an earlier stage of formation. pCea - mafic granulite and minor amphibolite.|16-MAY-23
26755|Mount Bleechmore Granulite|Relationships and boundaries|pCe - Together with the Kanandra Granulite and the Yambah Granulite considered to be the oldest rocks in the Sheet area; considered to conformably underlie Chiripee Gneiss which has a similar dominent lithology but is of a lower metamorphic grade. pCeg - a mobilized part of the sequence, pCea - Considered to be mainly dykes and sills intrusive into the felsic gneiss and pelite before metamorphism.|16-MAY-23
26755|Mount Bleechmore Granulite|Identifying features|Distinguished from Chiripee Gneiss by presence of abundant mafic rocks and from Kanandra Granulite by the presence of a considerable content of pelitic gneiss.|16-MAY-23
26755|Mount Bleechmore Granulite|Correlations|Tentative correlations: As for Kanandra Granulite.|16-MAY-23
26755|Mount Bleechmore Granulite|Proposed publication|BMR Report|16-MAY-23
26755|Mount Bleechmore Granulite|Name first published by|Shaw R.D., Warren R.G., Kopras J., Green D.E., 1975|16-MAY-23
26755|Mount Bleechmore Granulite|Unit name|Mount Bleechmore Granulite (pCe, pCeg, pCega)|16-MAY-23
12528|Mount Bonner Sandstone|Name source|From Mount Bonner, a prominent landmark on northeastern coast of peninsula between Arnhem and Melville Bays.|16-MAY-23
12528|Mount Bonner Sandstone|Type section locality|Reference Area: Vicinity of Mount Bonner designated as reference area.|16-MAY-23
12528|Mount Bonner Sandstone|Extent|Crops out in a northeasterly trending zone covering an area of 25 km 2 on peninsula between Arnhem and Melville Bays, in the northeastern part of Arnhem Bay/Gove Sheet area.|16-MAY-23
12528|Mount Bonner Sandstone|General description|In most places a bed of conglomerate, up to 30 m thick, occurs at the base of the formation. The conglomerate contains boulders, cobbles, and pebbles of white and pink quartz sandstone, quartz, quartzite, and rarely, granite. Cobbles of quartz sandstone make up most of the rock. The matrix consists of coarse-grained quartz sandstone. The conglomerate is overlain by about 120 m of white cross-bedded quartz sandstone. It is dominantly coarse-grained, massive, and thin-bedded, although medium-grained zones and zones of feldspathic sandstone occur in parts of the sequence. The grains are subrounded to angular. Ripple marks are present, but are not abundant. Bedding laminations are commonly accentuated by concentrations of black minerals. Jointing of the sandstone tends to produce karst topography. In thin section (R12656) the rock is seen to contain minor rock fragments as well as poorly sorted quartz sand. The rock fragments include quartzite, chert, and volcanic rocks. Suturing is the main form of cementation, but overgrowths are more abundant in the finergrained zones. Sericite occurs interstitially and a small amount of barite cement is present in some bands.|16-MAY-23
12528|Mount Bonner Sandstone|Thickness range|About 150 m.|16-MAY-23
12528|Mount Bonner Sandstone|Lithology|White, massive, thin-bedded, coarse-grained quartz sandstone; massive cobble conglomerate.|16-MAY-23
12528|Mount Bonner Sandstone|Relationships and boundaries|Unconformable on Spencer Creek Volcanics and, at one locality on east coast of peninsula, rests directly on weathered garnetiferous granite (probably Bradshaw Granite); overlain, probably conformably, by Wilberforce Beds. Although they rarely crop out, the Wilberforce Beds probably underlie much of the peninsula north of the exposures of the Mount Bonner Sandstone; no contacts between the two units have been observed.|16-MAY-23
12528|Mount Bonner Sandstone|Identifying features|The base of the Mount Bonner Sandstone is generally marked by rudites, but in places arenites occur at the base. Both rock types are readily distinguished from the underlying volcanic or granitic rocks. The top of the unit is assumed to lie along a line marked by a sharp physiographic break produced by a change in lithology from arenites to less resistant strata. The less resistant strata are not exposed near the contact.|16-MAY-23
12528|Mount Bonner Sandstone|Age reasons|Statherian or Calymmian (Palaeoproterozoic or Mesoproterozoic)|16-MAY-23
12528|Mount Bonner Sandstone|Defn author|Plumb and Roberts (1992),|16-MAY-23
12528|Mount Bonner Sandstone|Comments|As a basal sandstone and conglomerate unit, the Mount Bonner Sandstone has traditionally been correlated with the Parsons Range or Katherine River Groups (Plate1; Plumb & Derrick, 1975). However, basal sandstones now characterise each of the principal carbonate rich groups to the south - the McArthur or the Nathan Groups (Jackson et aL, 1987). The upper limit of the Mount Bonner Sandstone - Wilberforce beds pair is constrained only by the Roper Group equivalent, the Malay Road Group, and so the Mount Bonner Sandstone may be correlated with the basal sandstone of either the McArthur or Nathan Groups (Plumb et aL, 1990).|16-MAY-23
27066|Mount Bonnie Formation|Name source|Mount Bonnie mine (131o33'E, 13o33'S). Pine Creek 1:250 000 Sheet area.|16-MAY-23
27066|Mount Bonnie Formation|Unit history|Walpole & others (1968) included these beds in the Koolpin Formation in the Alligator River and Mount Evelyn 1:250 000 Sheet areas and in the Goldlen Dyke Formation in the Darwin and Pine Creek 1:250 000 Sheet areas. Described by Goulevitch (1980) as Kapalga Formation and included by Needham & others (1980a) in the Kapalga Formation.|16-MAY-23
27066|Mount Bonnie Formation|Type section locality|(131o43'E, 12o59'S; Darwin 1:250 000 Sheet area) 450 m of interbedded argillite, shale, siltstone, greywacke, tuff, and shale with black or white chert bands, lenses, and nodules exposed along the northern bank of the Mary River from GR 945639 to 948640 (Mary River 1:100 000 Sheet area). Reference area: Well-exposed ridges and drill-core intersections in the Margaret Syncline around the Mount Bonnie mine.|16-MAY-23
27066|Mount Bonnie Formation|Extent|The unit forms well-exposed ridges in the Alligator River, Darwin, Pine Creek, and Mount Evelyn 1:250 000 Sheet areas.|16-MAY-23
27066|Mount Bonnie Formation|Thickness range|650 to 850 m, locally thins to 200 to 300 m.|16-MAY-23
27066|Mount Bonnie Formation|Lithology|Interbedded shale, siltstone, shale with black or white chert bands, lenses, and nodules, argillite, tuffaceous chert, black glassy crystal tuff, greywacke, minor silicified dolomite and banded iron formation.|16-MAY-23
27066|Mount Bonnie Formation|Relationships and boundaries|Conformably overlies the Gerowie Tuff and is conformably overlain by the Burrell Creek Formation. The base of the unit is defined as the base of the lowermost greywacke. The unit also contains a smaller proportion (less than 10 percent) of tuff and argillite compared to the Gerowie Tuff. The top of the unit is defined by the uppermost unit of either argillite, tuff, shale containing chert bands, lenses, and nodules, or banded iron formation.|16-MAY-23
27066|Mount Bonnie Formation|Age reasons|Early Proterozoic, as it forms part of the Early Proterozoic metasedimentary sequence of the Pine Creek Geosyncline which overlies verified Archaean rocks (Page & others, 1980), and underlies the Kombolgie Formation which locally is the lowermost unit in the McArthur Basin Carpentarian sequence.|16-MAY-23
27066|Mount Bonnie Formation|Proposed publication|1:100 0000 Map Commentary|16-MAY-23
27066|Mount Bonnie Formation|Defn approved by|Brakel A.T., Abell R., Mrown M.|16-MAY-23
27066|Mount Bonnie Formation|Proposer|Stuart-Smith P.G.|16-MAY-23
12580|Mount Chapple Metamorphics|Name source|Mount Chapple 132o 40'E 23o 18'S.|16-MAY-23
12580|Mount Chapple Metamorphics|Unit history|Previously the Mount Chapple granulite (used informally: Glikson, 1984, 1987).|16-MAY-23
12580|Mount Chapple Metamorphics|Geomorphic expression|Rough rubbly hills.|16-MAY-23
12580|Mount Chapple Metamorphics|Type section locality|Type area: Between Dam No.30 and 1km northeast of No.10 bore, Narwietooma 1:100 000 sheet area.|16-MAY-23
12580|Mount Chapple Metamorphics|Extent|Forms the Mount Chapple massif and ridges extending to Karanji Bore.|16-MAY-23
12580|Mount Chapple Metamorphics|Lithology|Mafic to intermediate granulite, granitic gneiss, quartzofeldspathic gneiss, metasediments.|16-MAY-23
12580|Mount Chapple Metamorphics|Relationships and boundaries|Isolated massif.|16-MAY-23
12580|Mount Chapple Metamorphics|Structure and Metamorphism|Complexly folded and metamorphosed as for Narwietooma Metamorphic Complex.|16-MAY-23
12580|Mount Chapple Metamorphics|Age reasons|Middle Proterozoic: affected by Strangways metamorphism 1760-1750 Ma.|16-MAY-23
12580|Mount Chapple Metamorphics|Correlations|Part of Narwietooma Metamorphic Complex.|16-MAY-23
12580|Mount Chapple Metamorphics|Defn author|Glikson, A.Y., (1987), Shaw, R.D., Warren, R.G. (1985)|16-MAY-23
12580|Mount Chapple Metamorphics|Comments|References are missing. No evidence that this 'definition' was ever approved, although indexed article by Watt, 1992 has comment saying 'definition with convenor'.|16-MAY-23
12596|Mount Cornish Formation|Type section locality|Smith (1964) says the best exposure (the type section) is near Mount Cornish, Lat. 22deg 48' S, Long. 136deg 28'30'' E.|16-MAY-23
12596|Mount Cornish Formation|General description|The Mount Cornish Formation of Smith (1964) is here redefined to exclude the lower 26 m in the type section; i.e. to exclude the basal sandstone and dolomite, which are here assigned to the Yackah Beds. The original type section is retained, but is extended stratigraphically higher through an area of poor outcrop, giving the formation a thickness of 680 m without the top being exposed (Walter, 1979). The section runs from 4 km WSW to 48 km SSW of Mt Cornish, Huckitta 1:250 000 Sheet area. The base of the formation is placed at the base of the lowermost diamictite.|16-MAY-23
24395|Mount Davenport Diamictite Member|Name source|The name is derived from Mount Davenport at the south-western end of the Treuer Range (6824:5264) on the Mount Doreen 1:250 000 Sheet area (SF 52-12).|16-MAY-23
24395|Mount Davenport Diamictite Member|Type section locality|The type section, WX-2, is located in the eastern slopes of the Naburula Hills (7385:5336) and is the same as the type section of the Mount Doreen Formatio0n.|16-MAY-23
24395|Mount Davenport Diamictite Member|Extent|The Mount Davenport Diamictite Member occurs in sporadic outcrops along the northern margin of the Ngalia Basin as far west as Albinia Springs and as far east as Naburula Hills.|16-MAY-23
24395|Mount Davenport Diamictite Member|Thickness range|The thickness in the type section is 77.4 m. An incomplete sequence of 61 m was measured in a neighbouring section. Most other exposures are incomplete so that no information is available on the regional variation in thickness of the member.|16-MAY-23
24395|Mount Davenport Diamictite Member|Lithology|In the type section the Member consists of a polymictic boulder conglomerate with erratics up to 4 m across of predominantly metamorphic and igneous rock types, of which granite and quartzite are the most common; faceting and striations are common. The matrix is mostly a blue-green, some red-brown and green poorly sorted siltstone with abundant angular quartz and rock fragments. A few thin lenses of sandstone and sandy dolomite, and pebbly sandstone occur near the base of the member. Lithological variations: In some places outside the type section the large striated erratics are absent and the member consists of dolomitic pebble (commonly chert) conglomerate.|16-MAY-23
24395|Mount Davenport Diamictite Member|Relationships and boundaries|The Davenport Diamictite Member is conformably overlain by the Wanapi Dolomite Member and overlies the Rinkabeena Shale, probably disconformably. In places it is overlain with an angular unconformity by the Mount Eclipse Sandstone.|16-MAY-23
24395|Mount Davenport Diamictite Member|Identifying features|Reason for proposed name: The Member comprises an easily recognised part of the Mount Doreen Formation which has been described but not previously named.|16-MAY-23
24395|Mount Davenport Diamictite Member|Age reasons|The lithology and superposition of the member indicates that it is late Proterozoic in age. It can be correlated with the Olympic Member of the Pertatataka Formation in the Amadeus Basin. In the Vaughan Springs Syncline it may unconformably overlie the Albinia Formation.|16-MAY-23
24395|Mount Davenport Diamictite Member|Proposed publication|The Geology of the Ngalia Basin, Northern Territory, Bureau of Mineral Resources, Geology & Geophysics, Bulletin|16-MAY-23
24395|Mount Davenport Diamictite Member|Defn Reference|83/24047|16-MAY-23
27660|Mount Deane Volcanic Member|Name source|Mount Deane - GR 296580 on the Batchelor 1:100 000 Sheet (5171).|16-MAY-23
27660|Mount Deane Volcanic Member|Type section locality|Small ridge 300 m east of Mount Deane composed of greenish grey fine grain rock with residual felted texture in places and rare breccia (?flow breccia) and silica lined vugs (amygdales).|16-MAY-23
27660|Mount Deane Volcanic Member|Extent|Generally small isolated outcrop, no more than 1 km by 0.5 km in size in the north-western part of the Batchelor 1:100 0000 Sheet area (5171) and south-western part of the Noonamah 1:100 000 Sheet area (5172).|16-MAY-23
27660|Mount Deane Volcanic Member|Thickness range|Up to 200 m.|16-MAY-23
27660|Mount Deane Volcanic Member|Lithology|Greenish-grey altered basic volcanic which weathers to a soft, rust-brown clayey rock, commonly displaying residual felted texture.|16-MAY-23
27660|Mount Deane Volcanic Member|Relationships and boundaries|Conformably overlies and underlies siltstones and shales of the Wildman Siltstone (Needham and Stuart-Smith, 1978) of which it is a member. Homogeneous lithology from base to top.|16-MAY-23
27660|Mount Deane Volcanic Member|Age reasons|The unit is contained within known Early Proterozoic sediments of the Pine Creek Geosyncline.|16-MAY-23
27660|Mount Deane Volcanic Member|Proposed publication|BMR Report|16-MAY-23
27660|Mount Deane Volcanic Member|First Reference|83/23944  Nov. 1983|16-MAY-23
27660|Mount Deane Volcanic Member|Proposer|Crick I.H.|16-MAY-23
12639|Mount Doreen Formation|Identifying features|The original definition of the Mount Doreen Formation is here amended because it is now believed that a disconformity is present in its lower part. The formation was described (Wells et al., 1972) as consisting of red shale at the top followed by thin beds of pink dolomite, diamictite, and green shale at the base. The disconformity occurs between the diamictite and underlying green shale. The shale is here defined as the Rinkabeena Shale and the name Mount Doreen is retained for the upper part of the sequence.  The lower boundary of the formation is taken as the contact between diamictite of the Mount Doreen Formation with green shale of the Rinkabeena Shale.|16-MAY-23
12639|Mount Doreen Formation|Defn author|Preiss W.V., Walter M.R., Coats R.P., Wells A.T., 1978|16-MAY-23
12639|Mount Doreen Formation|Proposed publication|The Stratigraphy & Structure of the Ngalia Basin, Northern Territory, Bureau of Mineral Resources, Geology & Geophysics Bulletin.|16-MAY-23
12639|Mount Doreen Formation|Defn Reference|83/24047|16-MAY-23
12780|Mount Harris Basalt|Name source|Mount Harris 24o 38' 11.52" S, 129o 30' 51.48 E (WGS 84).|16-MAY-23
12780|Mount Harris Basalt|Unit history|Previously described as epidotized amygdaloidal basalt, tuff, agglomerate, quartzite and possibly including quartz-feldspar porphyry (Forman 1966)|16-MAY-23
12780|Mount Harris Basalt|Constituents|Nil|16-MAY-23
12780|Mount Harris Basalt|Geomorphic expression|Low to moderate rounded hills|16-MAY-23
12780|Mount Harris Basalt|Type section locality|10.5 km southwest of Mount Harris at location 24o 40' 35.69" S, 129o 24' 50.91 E (WGS 84).|16-MAY-23
12780|Mount Harris Basalt|Extent|Northeastern section of Hull 100 000 mapsheet, northwestern section of Bloods Range 1:100 000 mapsheet, northeastern section of Scott and southeastern section of Rawlinson 1:250 000 mapsheets (WA).|16-MAY-23
12780|Mount Harris Basalt|Thickness range|Estimated minimum thickness of 1-2 km. Lower stratigraphic contact not exposed. Strong deformational overprint has resulted in structural thickening of unit.|16-MAY-23
12780|Mount Harris Basalt|Lithology|Amygdaloidal basalt, epidotised and silicified basalt with rare crystalline quartz sandstone.|16-MAY-23
12780|Mount Harris Basalt|Depositional environment|Limited evidence suggests a possible subaqueous depositional environment.|16-MAY-23
12780|Mount Harris Basalt|Relationships and boundaries|Overlain by Puntitjata Rhyolite or Bloods Range Formation. No lower stratigraphic contact exposed.|16-MAY-23
12780|Mount Harris Basalt|Age reasons|Mesoproterozoic. Intruded by the 1084 +/- 9 Ma Walu Granite and by mafic dykes equivalent to the ~1078 Ma Alcurra Dyke Swarm. Overlain by the Puntitjata Rhyolite (1075+/- 2 Ma).|16-MAY-23
12780|Mount Harris Basalt|Correlations|Mummawarrawarra Basalt of the Tollu Group. The Smoke Hill Felsic Volcanics of the Tollu Group crosscut the Mummawarrawarra Basalt and are dated at 1078 +/- 5 Ma (Sun et al. 1996).|16-MAY-23
12780|Mount Harris Basalt|Proposed publication|Close, D.F., Edgoose, C.J., Scrimgeour, I.R., 2002. Bloods Range and Hull 1:100 000 geological special, Northern Territory Geological Survey, Explanatory notes.|16-MAY-23
12780|Mount Harris Basalt|Comments|Redefinition of unit includes a minimum 1-2 km thick sequence of basalt with rare sedimentary interbeds. No quartz-feldspar porphyry subunit. Strong layering evident in outcrop. Due to thrust stacking and strong foliation overprint during the 570-530 Ma Petermann Orogeny, stratigraphic thickness is estimated as a minimum only.|16-MAY-23
12780|Mount Harris Basalt|References|98/29502 - Forman, D.J., 1966. Bloods Range Northern Territory 1:250 000 geological series explanatory notes. Sheet (SG53-3). Bureau of Mineral Resources, Australia. **97/28568 - Sun, S-S., Sheraton, J.W., Glickson, A.Y. & Stewart, A.J., 1996. A major magmatic event during 1050-1080 Ma in central Australia and an emplacement age for the Giles Complex. AGSO Research Newsletter, 24, 13-15.|16-MAY-23
12786|Mount Hay Granulite|Name source|Mount Hay 133o 05' 23o 28'.|16-MAY-23
12786|Mount Hay Granulite|Unit history|Previously Mount Hay granulites, Mount Hay basic granulite (used informally: Black et al., 1983; Black & McCulloch 1984, Glikson 1987).|16-MAY-23
12786|Mount Hay Granulite|Geomorphic expression|Rough rubbly hills.|16-MAY-23
12786|Mount Hay Granulite|Type section locality|Southeast of Valley Bore, GR 306700 7408700 Anburla 1:100 000 Sheet area [assume AGD66 datum + Australian Map Grid].|16-MAY-23
12786|Mount Hay Granulite|Extent|Forms the Mount Hay massif and the low ridge of Ceilidh Hill.|16-MAY-23
12786|Mount Hay Granulite|Lithology|Mafic granulite, quartzofeldspathic gneiss, meta-leucogabbro, quartzose metasediments, calc-silicate rock.|16-MAY-23
12786|Mount Hay Granulite|Relationships and boundaries|Intruded by Anburla Anorthosite.|16-MAY-23
12786|Mount Hay Granulite|Structure and Metamorphism|Complexly folded and metamorphosed as for Narwietooma Metamorphism Complex.|16-MAY-23
12786|Mount Hay Granulite|Age reasons|Middle Proterozoic: affected by Strangways metamorphism at 1760-1750 Ma.|16-MAY-23
12786|Mount Hay Granulite|Correlations|Part of the Narwietooma Metamorphic Complex.|16-MAY-23
12786|Mount Hay Granulite|Defn author|Black, L.P., Shaw, R.D., Stewart, A.J. , 1983.|16-MAY-23
12786|Mount Hay Granulite|Comments|This 'definition' is missing the details of references mentioned in the synonymy, and shows no signs on the card of having been approved.|16-MAY-23
83008|Mount Lamb Suite|Name source|The Mount Lamb Suite is named after Mount Lamb (GDA94, 53K, 636123mE, 7842205mN), which lies towards the centre of the 1:250 000 scale mapsheets that this suite is interpreted to underlie, namely ALROY and FREW RIVER.|16-MAY-23
83008|Mount Lamb Suite|Geomorphic expression|No known outcrops.|16-MAY-23
83008|Mount Lamb Suite|Type section locality|Suites are not required to have a type locality. A Type Unit has been nominated: Francis Dam Granodiorite. This has been nominated as the type unit as it is intersected extensively in drill core NDIBK09 (608328 mE 7843609 mN, MGA94 zone 53 / 19.499208S 136.032320E), is robustly dated and is centrally located within the known extent of the Mount Lamb Suite.|16-MAY-23
83008|Mount Lamb Suite|Description at type locality|The Francis Dam Granodiorite (type unit) is a medium- to coarse-grained granodiorite comprising plagioclase, K-feldspar, quartz and minor weakly oriented biotite, white mica and hornblende, with traces of apatite, zircon, titanite and rutile.|16-MAY-23
83008|Mount Lamb Suite|Extent|Constituent units of this suite are recognised in drillholes NDIBK01, NDIBK09, NDIBK10 and WNWE029; geophysical evidence shows that these units, and other unnamed granitic/igneous bodies, extend widely throughout the ALROY and FREW RIVER mapsheets, and also underlie parts of TENNANT CREEK, BONNEY WELL, AVON DOWNS, RANKEN and BRUNETTE DOWNS (Clark et al., 2021).|16-MAY-23
83008|Mount Lamb Suite|General description|Dominantly granodiorite, monzogranite and alkali-feldspar granite.|16-MAY-23
83008|Mount Lamb Suite|Thickness range|Thicknesses of the constituent units of the Mount Lamb Suite are uncertain due to their igneous nature and the lack of outcrop with which to better constrain their true thicknesses. Approximately 190 m of Francis Dam Granodiorite is intersected in drillhole NDIBK09. The Duckling Granodiorite occurs as several 1?3 metre intervals in NDIBK01. The Joey Granite comprises two interval in drill core NDIBK10, one of approximately one metre, and the type interval of 8.5 metres. The Kurt Johansen Granite is intersected across 40 metres of drillhole WNWE029, and is also intersected in six other nearby shallow drillholes (Pellat and Fulton, 2012).|16-MAY-23
83008|Mount Lamb Suite|Lithology|Dominantly granodiorite, monzogranite and alkali-feldspar granite.|16-MAY-23
83008|Mount Lamb Suite|Relationships and boundaries|Constituents of the Mount Lamb Suite intrude the Alroy Formation. Intruded by the Quart Pot Granite.|16-MAY-23
83008|Mount Lamb Suite|Identifying features|The main diagnostic characteristics for the Mount Lamb Suite are an age of between 1855 and 1845 Ma, implying broadly comagmatic emplacement, and a geographic location within, or near, the ALROY 1:250k mapsheet. Most units are characterised by magnetically bland and low-density bodies in magnetics and gravity geophysical imagery. Relative to the Tennant Creek Supersuite (including the nearby Mulgar Granite), the Mount Lamb Suite is more restricted known SiO2 range and has lower concentrations of TiO2, total FeO, high field strength elements and medium to have rare earth elements at equivalent SiO2 levels.|16-MAY-23
83008|Mount Lamb Suite|Structure and Metamorphism|Constituent units are locally foliated, faulted and/or sheared, but are generally massive in texture and preserve primary igneous textures. This is interpreted to indicate that the Suite predates significant deformation, but that strain was largely taken up by the weaker pelitic rocks of the surrounding Alroy Formation.|16-MAY-23
83008|Mount Lamb Suite|Age reasons|1855 to 1845 Ma from U-Pb SHRIMP dating of constituent units. (Kositcin, Cross et al. in prep).|16-MAY-23
83008|Mount Lamb Suite|Correlations|Similar in age, geochemistry, and isotopic composition to the Tennant Creek Supersuite and Nicholson Granite Complex.|16-MAY-23
83008|Mount Lamb Suite|Alteration and Mineralisation|Unknown.|16-MAY-23
83008|Mount Lamb Suite|Geophysical Expression|Generally less dense than surrounding Alroy Formation, which the suite intrudes, and magnetically bland.|16-MAY-23
83008|Mount Lamb Suite|Geochemistry|Restricted known compositional range. Felsic (SiO2 = 72.2?74.5 wt.%), High-K (K2O > 4.89 wt.%), peraluminous (aluminium saturation index = 1.1?1.4) composition. Evolved whole rock Nd isotope composition (epsilon Nd ~1850 Ma = -1.82 to -5.55).|16-MAY-23
83008|Mount Lamb Suite|Defn author|A.D. Clark 24-MAR-2022|16-MAY-23
83008|Mount Lamb Suite|Proposed publication|Schofield and Clark et al., (in prep). Geology of the East Tennant area, Northern Territory, journal publication.|16-MAY-23
83008|Mount Lamb Suite|Comments|Geochemical characteristics and presence of hornblende suggest an I-type affinity, although this is somewhat at odds with peraluminous bulk rock compositions.|16-MAY-23
83008|Mount Lamb Suite|References|Kositcin, N., Cross A.J., et al., in prep. Geochronology of the East Tennant area, Geoscience Australia record.  **Pellatt, A., and Fulton, R., 2012. Grouped Annual Report (GR-097/09) for EL 9979, EL 24607, EL 26185, EL 26584, EL 26585, EL 26586, EL 26589, EL 28233, SEL 26451 and SEL 26452 (Wonarah Phosphate Project) for the period ending 8 January 2012, Company report published by the Northern Territory Geological Survey (Report ID CR2012-0053).  **Clark, A., Highet, L., Schofield, A., Doublier, M., 2021. Solid Geology map of the East Tennant region, dataset, Geoscience Australia.|16-MAY-23
13012|Mount Partridge Group|General description|The name was defined by Needham and others (1980) as containing the Mundogie Sandstone, Mount Hooper Sandstone, Wildman Siltstone and Acacia Gap Sandstone Member, and Nourlangie Schist. Owing to uncertainty in correlation between the Nourlangie Schist and other units in the group, and the fact that the Nourlangie Schist is essentially a metamorphic unit, this formation was dropped from the Mount Partridge Group by Needham (1984). Recorrelation of units in the Rum Jungle area and recognition of a regional unconformity within the now no longer used "Batchelor Group", has resulted in the addition of the Crater Formation and Coomalie Dolomite to the Mount Partridge Group (Needham & Stuart-Smith, in prep.).  Crick (in prep.) redefines the pelitic sequence in the Rum Jungle area stratigraphically between the Coomalie Dolomite and Acacia Gap Quartzite Member as the Whites Formation; this sequence was previously correlated with the Masson Formation of the Namoona Group by Needham & others (1980). The Mundogie Sandstone has been extended to include similar rocks in the West Alligator River area which were differentiated by Needham & others (1980) as the Mount Hooper Sandstone (Needham & Stuart-Smith, 1984).  Thus the Mount Partridge Group as redefined contains five formations: Coomalie Dolomite, Crater Formation, Mundogie Sandstone, Whites Formation, Wildman Siltstone.|16-MAY-23
13012|Mount Partridge Group|Proposed publication|Changes in strat. Nom. And correlation. BMR Journal Needham & Stuart-Smith (in prep.)|16-MAY-23
79324|Mount Peake Gabbro|Name source|After Mount Peake GDA94 Zone 53K 299900mE 7617000mN in ANNINGIE  1:100 000 sheet 5554 in MOUNT PEAKE 1:250 000 sheet SF53-05, Northern Territory.|16-MAY-23
79324|Mount Peake Gabbro|Unit history|Previously informally named Mount Peake gabbro.|16-MAY-23
79324|Mount Peake Gabbro|Geomorphic expression|None. Does not crop out.|16-MAY-23
79324|Mount Peake Gabbro|Type section locality|Diamond drillhole SD (Stirling Deeps) DD001 MGA94 Zone 53K, 323000 mE, 7606200 mN in ANNINGIE 1:100 000 sheet . The drillcore is accessible at the NTGS Core Facility in Alice Springs.|16-MAY-23
79324|Mount Peake Gabbro|Description at type locality|Medium- to coarse-grained, ophitic textured olivine gabbro.|16-MAY-23
79324|Mount Peake Gabbro|Extent|Extends over an area of ~10 x 20 km subsurface but is non-outcropping (http://www.tngltd.com.au/projects/mount_peake_fe_v_ti/regional_exploration.phtml; accessed 11/02/2016).|16-MAY-23
79324|Mount Peake Gabbro|General description|Non outcropping sill or sill complex (http://www.tngltd.com.au/projects/mount_peake_fe_v_ti/regional_exploration.phtml; accessed 11/02/2016).|16-MAY-23
79324|Mount Peake Gabbro|Thickness range|250-300 m (http://www.tngltd.com.au/projects/mount_peake_fe_v_ti/regional_exploration.phtml; accessed 11/02/2016).|16-MAY-23
79324|Mount Peake Gabbro|Lithology|Olivine gabbro, gabbro, leucogabbro, magnetite-rich olivine gabbro and minor ultramafic rocks.|16-MAY-23
79324|Mount Peake Gabbro|Relationships and boundaries|Intrusive lower contact where fine-grained gabbro is in contact with haematitised siltstone overlying quartzite that in turn overlies porphyritic granite. The igneous crystallisation age of the gabbro and consequent intrusive age of the sill is consistent with the interpretation that the sedimentary country rocks and the granite are constituent units of the local (Palaeoproterozoic) basement, likely Lander Rock Formation (or equivalent) and ca 1789 Ma Esther Granite (Cross et al 2005) respectively.|16-MAY-23
79324|Mount Peake Gabbro|Identifying features|As the Mount Peake Gabbro does not outcrop, it is distinguished on the basis of a magnetic signature.|16-MAY-23
79324|Mount Peake Gabbro|Structure and Metamorphism|Apparently undeformed and largely unmetamorphosed, but locally partially uralitised.|16-MAY-23
79324|Mount Peake Gabbro|Age reasons|LA-ICPMS zircon and baddeleyite dating of an apparently massive gabbro from the interval 83.25 to 204.21m in diamond drillhole SDDD001 yielded magmatic 207Pb/206Pb crystallisation ages of 1053 +/- 24 Ma and 1062 +/- 21 Ma, respectively (Beyer et al 2016).|16-MAY-23
79324|Mount Peake Gabbro|Correlations|The age for the Mount Peake Gabbro is within uncertainty of the Sm-Nd mineral isochron age reported for the Stuart Pass Dolerite 1076 +/- 33 Ma (Zhao and McCulloch 1993), and the two units are correlated. Mount Peake Gabbro is therefore interpreted to be another constituent unit of the ca 1078-1070 Ma Warakurna Large Igneous Province (Wingate et al 2004).|16-MAY-23
79324|Mount Peake Gabbro|Alteration and Mineralisation|V-Ti-Fe mineralisation in cumulate, magnetite-rich layers (http://www.tngltd.com.au/projects/mount_peake_fe_v_ti/regional_exploration.phtml; accessed 11/02/2016).|16-MAY-23
79324|Mount Peake Gabbro|Geophysical Expression|NE-trending zone of high magnetic susceptibility in the semi-regional airborne magnetic data. Moyle and Wetherley (2009) reported that 3D modelling of this magnetic anomaly indicated a zone of high-magnetic susceptibility and locally coincident gravity anomaly surrounding a circular zone of lower magnetic susceptibility.|16-MAY-23
79324|Mount Peake Gabbro|Geochemistry|Ten samples of apparently largely homogeneous unmineralised olivine-bearing and olivine gabbro from the interval 83-204m in diamond drillhole SDDD001 plot in the tholeiite field in an AFM diagram, where they define a short fractionation trend. In a modified Jensen diagram (Jensen 1976; Viljoen et al, 1982) these samples plot on the boundary between normal- and iron-tholeiite. CIPW normative compositions calculated on the basis of an an Fe2O3/FeO ratio of 0.2 include three samples with minor ne (<2 wt%), and the remainder have no normative Q and <10 wt% hyp suggesting transitional rock compositions. When the norm is calculated using an Fe2O3/FeO based on the measured FeO values no samples are ne or Q normative, and only one sample has >10 wt% hyp. Rare earth element geochemistry, in particular slight positive Eu-anomalies when normalised relative to chondrite, indicate some plagioclase accumulation. A plot of CaO vs. MgO is consistent with cumulate olivine in some samples.|16-MAY-23
79324|Mount Peake Gabbro|Defn author|Nigel Donnellan and Eloise Beyer 11-FEB-2016.|16-MAY-23
79324|Mount Peake Gabbro|References|Beyer EE, Donnellan N, Meffre S and Thompson J, 2016. Summary of Results. NTGS laser ablation ICP-MS in situ zircon and baddeleyite geochronology project: Mount Peake Gabbro, Arunta Region, July 2015-June 2016. Northern Territory Geological Survey, Record 2016-XXXX. **Cross A, Claoue-Long JC, Scrimgeour IR, Crispe AJ and Donnellan N, 2005. Summary of results. Joint NTGS-GA geochronology project: northern Arunta and Tanami_regions, 2000-2003. Northern Territory Geological Survey, Record 2005-003.  **Jensen, L.S., 1976. A new cation plot for classifying subalkali volcanic rocks. Ontario Department of Mines, Miscellaneous Paper Number 66, 22pp. **Moyle S and Wetherley C, 2009. Enigma Mining Ltd, Stirling Deeps Project EL 23074 Drilling Report. Diamond drilling to confirm a layered mafic complex in the western Arunta Province and to assess potential for Ni-Cu sulphides and PGE mineralisation. Tennant Creek Gold Ltd. Northern Territory Geological Survey, Open File Company Report CR2009-1079. **Viljoen MJ, Viljoen RP and Pearton TN, 1982. The nature and distribution of Archaean komatiite volcanics in South Africa. In: Arndt NT and Nisbet EG (eds.), Komatiites. George Allen and Unwin, London, 53-79. **Whelan JA, Beyer EE and Donnellan N, 2016.  1.4 billion years of Northern Territory geology: insights from collaborative U-Pb zircon and baddeleyite dating, in: 'Annual Geoscience Exploration Seminar (AGES) 2016. Record of abstracts.' Northern Territory Geological Survey Record 2016-XXX. **Wingate MTD, Pirajno F, Morris PA, 2004. The Warakurna large igneous province: a new Mesoproterozoic large igneous province in west-central Australia. Geology 32, 105-108. **Zhao Jianxin and McCulloch MT, 1993. Sm-Nd isochron ages of Late Proterozoic dyke swarms in Australian: evidence for crustal extension. Chemical Geology (Isotope Geoscience Section) 109, 341-354.|16-MAY-23
27067|Mount Shepherd Rhyolite Member|Name source|Mount Shepherd, Katherine, Edith River Region 1:100 000 Sheet areas, NT GR 245073|16-MAY-23
27067|Mount Shepherd Rhyolite Member|Unit history|This lithology not previously described. The rhyolite was mapped as sandstone of the Kombolgie Formation by Walpole & others (1968).|16-MAY-23
27067|Mount Shepherd Rhyolite Member|Type section locality|Lower slopes of Mount Shepherd.|16-MAY-23
27067|Mount Shepherd Rhyolite Member|Extent|Exposed over about 11 km2 around Mount Shepherd, north of Dorothy Creek.|16-MAY-23
27067|Mount Shepherd Rhyolite Member|Thickness range|<110 m.|16-MAY-23
27067|Mount Shepherd Rhyolite Member|Lithology|Cream-purple banded fine siliceous massive rhyolite. In places flow-banded and flow-top breccia. Weathers buff or brown-orange, and from a distance commonly looks like Kombolgie Formation sandstone, especially when cliff-forming.|16-MAY-23
27067|Mount Shepherd Rhyolite Member|Relationships and boundaries|Rests on Tollis Formation with marked angular unconformity. Overlain by Kombolgie Formation with apparent conformity. Forms a member within the Plum Tree Creek Volcanics and appears to lie at or near the top of the formation. Relationships with Plum Tree Creek Volcanics lithologies north of Mount Shepherd not clear owing to Cainozoic cover, but it must either be a lateral equivalent of these rocks (ignimbrite and basalt) forming a steep-sided flow, or overlie them with an irregular contact. The absence of Plum Tree Creek Volcanics south of Mount Shepherd suggests the latter. The rock type is distinct in the region and boundaries should be sharp. The unit may correlate with other unnamed rhyolite bodies in the Mount Felix/Mount Lambell and Eva Creek headwaters areas, about 20 and 60 km east on Eva Valley and Waterhouse 1:100 000 Sheets respectively (also within Plum Tree Creek Volcanics).|16-MAY-23
27067|Mount Shepherd Rhyolite Member|Age reasons|Late Early Proterozoic. Its unconformable position beneath Kombolgie Formation (dated 1648 +/- 29 m.y., Rb/Sr whole rock + mineral separates isochron, Page, Compston & Needham, 1980), and the unconformabale position of other units within this group (Edith River Group) over 1780 m.y.-granites in the Stow Sheet indicate an age for the group of ~1700 +/- 50 m.y.  (Age of granite inferred from ages of similar granites in Pine Creek Geosyncline reported by Page, Compston & Needham, 1980, and Riley, 1980).|16-MAY-23
27067|Mount Shepherd Rhyolite Member|Proposed publication|1:100 000 map Commentary, Edith River Region|16-MAY-23
27067|Mount Shepherd Rhyolite Member|Category|2|16-MAY-23
27067|Mount Shepherd Rhyolite Member|Proposer|Needham S.|16-MAY-23
27067|Mount Shepherd Rhyolite Member|Resdate|09-MAR-1983|16-MAY-23
27067|Mount Shepherd Rhyolite Member|Reserved? Yes/No|Yes|16-MAY-23
72421|Mount Stafford Member|Name source|After Mount Stafford (53K 257700mE 7563350mN) in NAPPERBY (REYNOLDS RANGE).|16-MAY-23
72421|Mount Stafford Member|Unit history|Mount Stafford Beds (Shaw and Stewart 1975) in part, Mount Stafford beds (Stewart et al 1980).|16-MAY-23
72421|Mount Stafford Member|Geomorphic expression|Forms a prominent range.|16-MAY-23
72421|Mount Stafford Member|Type section locality|Well exposed in Yundurbulu Range, wherein a representative section from approximately 252500mE 7559300mN (22o03'07"S 132o36'11"E) in REYNOLDS RANGE (NAPPERBY) northeast to approximately 260800mE 7565750mN (21o59'42"S 132o41'04"E) in MOUNT PEAKE includes folded Mount Stafford Member crossed by a succession of prograde metamorphic isograds described by Vernon et al (1990). This section includes unit base (a concordant prograde metamorphic contact with otherwise laterally equivalent Woodalla Member), but top not exposed.|16-MAY-23
72421|Mount Stafford Member|Extent|In Yundurbulu Range in north-central NAPPERBY and adjacent south-central MOUNT PEAKE, where it extends into Bilba Hills.|16-MAY-23
72421|Mount Stafford Member|Thickness range|Probably <=1300 m.|16-MAY-23
72421|Mount Stafford Member|Lithology|Spotted and layered, predominantly metapelitic and subordinate metapsammitic hornfels (andalusite-corderite-K-feldspar, spinel-corderite-K-feldspar, orthopyroxene-garnet-cordierite-K-feldspar); local quartz-mica schist and phyllite (now largely included in Woodalla Member); migmatite; ortho-amphibolite.|16-MAY-23
72421|Mount Stafford Member|Depositional environment|Deep-water, turbiditc sedimentary (Greenfield et al 1996).|16-MAY-23
72421|Mount Stafford Member|Relationships and boundaries|Laterally equivalent to Woodalla Member. However, Woodalla Member is a lower metamorphic-grade equivalent of Mount Stafford Member. Top not exposed. Intruded by unnamed dolerite and granite and by Anmatjira Orthogneiss.|16-MAY-23
72421|Mount Stafford Member|Structure and Metamorphism|Polydeformed; major outcrop area comprises northwest-trending open anticlines and synclines.|16-MAY-23
72421|Mount Stafford Member|Age reasons|Late Orosirian. Maximum age of sedimentation 1869 Ma based on youngest coherent group of detrital zircons, 1866 ± 3 Ma (Claoué-Long et al in press). Intruded by Anmatjira Orthogneiss which has an igneous crystallisation age of 1795 ± 3 Ma (KE Worden, pers comm 2006). Stafford Event metamorphism is constrained to 1801 ± 2 Ma in correlative succession in northwestern NAPPERBY (J Claoué-Long and IR Scrimgeour, pers comm 2006).|16-MAY-23
72421|Mount Stafford Member|Correlations|Woodalla Member in part, and therefore probably also Lander Rock Formation in MOUNT DOREEN.|16-MAY-23
72421|Mount Stafford Member|References|Claoué-Long JC, Edgoose C and Worden KE, in press. A correlation of Arunta Region stratigraphy in central Australia. Precambrian Research.Greenfield JE, Clarke GE, Band M and Clark DJ, 1996. In-situ migmatite and hybrid diatexite at Mount Stafford, central Australia. Journal of Metamorphic Geology 14, 413-426.Shaw RD and Stewart AJ, 1975. Arunta Block - regional geology: in Knight CL (editor) `Economic geology of Australia and Papua New Guinea'. Australasian Institute of Mining and Metallurgy, Monograph 5, 437-442.Stewart AJ, Shaw RD, Offe LA, Langworthy AP, Warren RG, Allen AR and Clarke DB, 1980. Stratigraphic definitions of named units in the Arunta Block, Northern Territory. Bureau of Mineral Resources, Australia, Report 216.Vernon RH, Clarke GL and Collins WJ, 1990. Mid-crustal granulite-facies metamorphism: low-pressure metamorphism and melting, Mount Stafford, central Australia: in Ashworth JR and Brown M (editors) `High-temperature metamorphism and crustal anatexis¿. Special Publication of the Mineralogical Society 2, 272-319.|16-MAY-23
28815|Mount Thomas Quartzite|Name source|Mount Thomas (5453-734336), the highest point in the Reynolds Range.|16-MAY-23
28815|Mount Thomas Quartzite|Unit history|Mapped and referred to as Giles Quartzite and Ironbark Silts by Australian Geophysical (1967); included in 'Metasediments and metamorphics of uncertain origin' by Evans & Glikson (1969); mapped as 'Precambrian quartzite' by Wells & others (1971).|16-MAY-23
28815|Mount Thomas Quartzite|Type section locality|AX-1, 3 km east of Mount Thomas; base at 5453-775315, top at -763313 not measured.|16-MAY-23
28815|Mount Thomas Quartzite|Extent|Entire length of the Reynolds Range, in Aileron, Tea Tree, and Reynolds Range 1:100 0000 Sheet areas: also Giles Range, in the Reynolds Range and Denison 1:100 000 Sheet areas; also Wabudali Range, Mount Theo 1:250 000 Sheet area.|16-MAY-23
28815|Mount Thomas Quartzite|Thickness range|850 m in type section (excluding microgranite sills); 235 m in northwest part of Reynolds Range; about 550 m in southeast part of Range. All figures are estimates from airphoto measurements and dip information.|16-MAY-23
28815|Mount Thomas Quartzite|Lithology|At the type section, unit consists mostly of pinkish-brown thin-bedded silicified sandstone which is weakly schistose, cross laminated, and contains a small amount of detrital muscovite. Two sills of retrogressively metamorphosed microgranite of the Warimbi Schist intrude the lower part of the type section, and a third sill overlies the top of the section. Two interbeds of greenish-grey, weakly cleaved silstone with andalusite porphyroblasts are present, one immediately above the lower sills of microgranite, the other near the top of the section. In the southeast of the Reynolds Range, the sequence is generally similar, but the proportion of siltstone and shale is greater. In the northwest of the Range, the unit begins with a few metres of basal conglomerate or pebbly arkose, overlain by white to pink orthoquartzite (about 100 m), and then by blue hematite quartzite (about 125 m); shale is absent. The basal conglomerate is separated from the quartzite by the retrogressively lmetamorphosed microgranite sill of the Coniston Schist.|16-MAY-23
28815|Mount Thomas Quartzite|Relationships and boundaries|Overlies Lander Rock beds with an angular unconformity; conformable overlain by and interfingers with Pine Hill Formation. Intruded by orthoschist sills of Coniston and Warimbi Schists; adjoins and probably intruded by Yakalibadgi Microgranite and Mount Airy Orthogneiss; ;intruded by Napperby Gneiss.|16-MAY-23
28815|Mount Thomas Quartzite|Age reasons|Older than 1800-1500 m.y. preliminary Rb-Sr isochron date on Napperby Gneiss (L P Black, BMR, personal communication, 1974); hence Middle Proterozoic or older.|16-MAY-23
28815|Mount Thomas Quartzite|Proposed publication|Stratigraphic definitions in Arunta Block' - BMR Microfiche Report.|16-MAY-23
28815|Mount Thomas Quartzite|Defn Reference|80/20787|16-MAY-23
28815|Mount Thomas Quartzite|Name first published by|Offe L.A., Stewart A.J., 1977|16-MAY-23
28815|Mount Thomas Quartzite|Reserved? Yes/No|Yes|16-MAY-23
29774|Mount Zeil Granite|Name source|Mount Zeil 132o 24'E 23o 24'S.|16-MAY-23
29774|Mount Zeil Granite|Unit history|Previously included in Mount Zeil granulite (informal, Glikson, 1984).|16-MAY-23
29774|Mount Zeil Granite|Geomorphic expression|Rough boulder-strwen hill slopes.|16-MAY-23
29774|Mount Zeil Granite|Type section locality|North side of Mount Zeil, GR 350000 7411700, Glen Helen 1:100 000 Sheet area.|16-MAY-23
29774|Mount Zeil Granite|Extent|Occupies most of the mass of Mount Zeil, and a low area on the north side of the Mount Heughlin massif.|16-MAY-23
29774|Mount Zeil Granite|Lithology|Massive medium-grained orthogneiss with garnet, hornblende and/or orthopyroxene, medium-grained granitic gneiss, augen gneiss, banded migmatitic gneiss, narrow bands of mafic granulite.|16-MAY-23
29774|Mount Zeil Granite|Relationships and boundaries|Intrudes Bunghara Metamorphics.|16-MAY-23
29774|Mount Zeil Granite|Structure and Metamorphism|Contains variously deformed and metamorphosed granite phases emplaced at different stages during the Strangways Orogeny. Also cut by older high-grade redbank and younger low-grade Alice-Springs type mylonites (Shaw & Black 1991).|16-MAY-23
29774|Mount Zeil Granite|Age reasons|Middle Proterozoic, younger than Bunghara Metamorphics, affected by Strangways metamorphism at about 1760-1750 Ma.|16-MAY-23
29774|Mount Zeil Granite|Defn author|R.D. Shaw & R.G. Warren, 6 Mar 1985.|16-MAY-23
29774|Mount Zeil Granite|Comments|This 'definition' is missing the details of references mentioned in the synonymy, and shows no signs on the card of having been approved.|16-MAY-23
22460|Muckaty Sandstone Member|Name source|Muckaty property in west-central HELEN SPRINGS and east-central SOUTH LAKE WOODS.|16-MAY-23
22460|Muckaty Sandstone Member|Unit history|Undifferentiated 'basal sandstone and breccia' of Helen Spring Volcanics (Randal & Brown 1970).|16-MAY-23
22460|Muckaty Sandstone Member|Geomorphic expression|Prominent low ridges.|16-MAY-23
22460|Muckaty Sandstone Member|Type section locality|7-9km southeast of Helen Springs homestead: lower boundary stratotype- prominent hill at GRLV876564 (lat. 18o29'05"S, long. 133o56'20"E), where conglomerate of the Muckaty Sandstone Member unconformably overlies variegated  mudstone of the Mesoproterozoic Wiernty Formation; upper boundary stratotype- top of prominent scarp along northeastern margin of eroded dome near GRLV861573 (lat. 18o28'50"S, long. 133o55'50"E), where Member is conformably overlain by undifferentiated basalt of Helen Springs Volcanics; type area includes 16m-thick reference section (thickest known section) on southwestern margin of same dome at GRLV859567. Member intersected at 242.2-243.8m depth (reference section) in cored drillhole NTGS96/1 (GRMV214640 HELEN SPRINGS).|16-MAY-23
22460|Muckaty Sandstone Member|Extent|Localised outcrop on Tennant Creek Inlier in TENNANT CREEK and HELEN SPRINGS; subsurface continuation probable in some adjoining sheet areas.|16-MAY-23
22460|Muckaty Sandstone Member|Thickness range|Ranges from a few millimetres (e.g. at GRLV880582) to a maximum known 16m+ in reference section at GRLV859567.|16-MAY-23
22460|Muckaty Sandstone Member|Lithology|Medium- to thick-bedded brown-grey quartzarenite to sublitharenite; conglomeratic toward base, incorporating quartzarenite and mudstone clasts up to cobble size of underlying Mesoproterozoic units.|16-MAY-23
22460|Muckaty Sandstone Member|Relationships and boundaries|Of Helen Springs Volcanics. Overlies with angular unconformity a variety of folded Palaeo- and Mesoproterozoic units of the Tennant Creek Inlier. Conformably overlain by undifferentiated (volcanic) portion of Helen Springs Volcanics.|16-MAY-23
22460|Muckaty Sandstone Member|Structure and Metamorphism|Outcrops generally subcircular in plan, representing either original dunes or subsequent eroded domes.|16-MAY-23
22460|Muckaty Sandstone Member|Age reasons|Early Cambrian or possibly slightly older, based on early Middle Cambrian Gum Ridge Formation and Montejinni Limestone directly overlying Helen Springs Volcanics.|16-MAY-23
22460|Muckaty Sandstone Member|Correlations|Possibly Jindare Formation beneath Antrim Plateau Volcanics along northern margin of Daly Basin in PINE CREEK, FERGUSSON RIVER and KATHERINE|16-MAY-23
22460|Muckaty Sandstone Member|References|RANDAL, M.A. & BROWN, M.C., 1970- 1:250000 geological series explanatory notes. Helen Springs, N.T. Bureau of Mineral Resources, Australia.|16-MAY-23
13301|Mud Tank Carbonatite|Name source|Mud Tank, a water bore adjacent to the Carbonatite, at GR 430460 in the Alcoota 1:250 000 Sheet area.|16-MAY-23
13301|Mud Tank Carbonatite|Unit history|The unit has been referred to in an informal publication as the Strangways Range Carbonatite by Gellatly (1972). It has been referred to as the carbonatites of the Strangways Range by Crohn & Gellatly (1969) and Moore and Gray (1973). The name Mud Tank Carbonatite has been used by Stewart & Warren (1977), Warren (1978), Black & Gulson (1978), and Langworthy & Black (1978).|16-MAY-23
13301|Mud Tank Carbonatite|Type section locality|Large rounded knoll at GR 5751-545259, Laughlen 1:100 000 Sheet area.|16-MAY-23
13301|Mud Tank Carbonatite|Extent|Exposed as three rounded knolls approximately 2 km2 in area, 3 km northeast of Woolanga Bore, Laughlen 1:100 000 Sheet area.|16-MAY-23
13301|Mud Tank Carbonatite|Lithology|Carbonatite with apatite, zircon, ilmenite-magnetite and unusual amounts of trace elements, including rare earths.|16-MAY-23
13301|Mud Tank Carbonatite|Relationships and boundaries|There are no exposed contacts with adjacent basement schist and gneiss; outcrop areas of carbonatite are surrounded and isolated by Quaternary alluvium. The unit is distinguished by its unusual lithology. It is presumed to intrude unnamed basement metamorphics, pCsf.|16-MAY-23
13301|Mud Tank Carbonatite|Age reasons|Late Proterozoic. Dates of 732 +/- 5 m.y. (U-Pb on zircon) and 735 +/- 75 m.y. (Rb-Sr whole-rock) have been determined by Black & Gulson (1978).|16-MAY-23
13301|Mud Tank Carbonatite|Proposed publication|Stewart & others in prep.|16-MAY-23
13301|Mud Tank Carbonatite|Defn approved by|Branch C.T., Brown M. (per V Passmore)|16-MAY-23
13301|Mud Tank Carbonatite|Defn Reference|80/20787|16-MAY-23
13301|Mud Tank Carbonatite|Name first published by|Stewart A.J., Warren R.G., 1977|16-MAY-23
13318|Mudginberri Phonolite|Name source|Mudginberri Homestead' 132o52'E 12o36'S Alligator River 1:250 000 Sheet area.|16-MAY-23
13318|Mudginberri Phonolite|Type section locality|Track running west just north of Woolwonga Reserve northern boundary fence, 4.8 km west of junction with Darwin-Oenpelli road. Two poorly exposed dykes <2 m wide trend northwest - ground level exposures north and south side of track. 132o46'10"E 12o39'47"S.|16-MAY-23
13318|Mudginberri Phonolite|Extent|Scattered narrow dykes within 15 km radius of Mudginberri H.S.|16-MAY-23
13318|Mudginberri Phonolite|Thickness range|<10 m wide, generally >1 m.  Up to 400 m in length.|16-MAY-23
13318|Mudginberri Phonolite|Lithology|Dark green grey fine grained dyke rock, commonly porphyritic with phenocrysts of large euhedral sanidine and anorthoclase laths, small hexagonal nepheline prisms, and dark green acicular prisms of aegirine. Groundmass is generally fine-grained or glassy, with incipient amphibole and biotite crystallites.|16-MAY-23
13318|Mudginberri Phonolite|Relationships and boundaries|Straight parallel sided near vertical dykes cutting Nanambu Complex garnet gneiss, leucogneiss and granite. Apparently does not intrude Carpentarian Kombolgie Formation.|16-MAY-23
13318|Mudginberri Phonolite|Age reasons|Approx. 1350 m.y.  Total rock Rb-Sr isochron. K-Ar data yield unrealistic spread of between 2100 and 600 m.y.  Page & Needham (in prep.).|16-MAY-23
13318|Mudginberri Phonolite|Proposed publication|Journal of the Geological Society of Australia|16-MAY-23
83161|Mulgar Granite|Name source|Mulgar Granite is named after Mulgar Point Bore (GDA94, 53K, 516675mE, 7751759mN), which lies approximately 45 km to the southwest of the undercover extent of this unit.|16-MAY-23
83161|Mulgar Granite|Geomorphic expression|No known outcrops.|16-MAY-23
83161|Mulgar Granite|Type section locality|Drillhole NDIBK05, down-hole depth from 200.15 m to 293.8 m (EOH). Drillhole location 583236mE 7805105mN (MGA94 zone 53) / 19.848342S 135.794937E. Drill core is stored at the NTGS core library in Alice Springs.|16-MAY-23
83161|Mulgar Granite|Description at type locality|Grey to pink, potassium-feldspar megacrystic hornblende-biotite granite characterised by large euhedral microcline in a coarse-grained quartz, plagioclase, biotite, white mica and hornblende matrix. This phase of the Mulgar Granite is intruded by an equigranular medium-grained biotite granite, consisting of sericitic plagioclase, potassium feldspar, quartz, biotite and trace hornblende and muscovite. The boundaries between the megacrystic and medium-grained phases occur over approximately 10 to 20 mm, but are irregular and diffuse.|16-MAY-23
83161|Mulgar Granite|Extent|Uncertain due to lack of outcrop. However, the unit is mappable as a homogeneous magnetic high in regional geophysical imagery. In plan view, magnetic high is visible as a 60 km long by 20 km wide, east?west-trending body that is wrapped and locally cross-cut by major regional shear zones (Clark et al., 2021).|16-MAY-23
83161|Mulgar Granite|General description|Only known in the type interval. See description above.|16-MAY-23
83161|Mulgar Granite|Thickness range|Unknown. Bottom of unit is not exposed in drill core.|16-MAY-23
83161|Mulgar Granite|Lithology|Potassium-feldspar megacrystic hornblende-biotite granite, characterised by large euhedral microcline in a coarse-grained quartz, plagioclase, biotite, white mica and hornblende matrix, intruded by equigranular medium-grained biotite granite containing sericitic plagioclase, potassium feldspar, quartz, biotite and trace hornblende and muscovite.|16-MAY-23
83161|Mulgar Granite|Relationships and boundaries|Kalkarindji Suite basalt nonconformably overlies this unit.|16-MAY-23
83161|Mulgar Granite|Identifying features|Prominent potassium-feldspar phenocrysts and age (see below). Unlike most intrusives of the Mount Lamb Suite, the Mulgar Granite is characterised by moderate magnetic susceptibility in regional geophysical imagery, similar to many intrusives of the Tennant Creek Supersuite. The Mulgar Granite has similar geochemical trends to other constituents of the Tennant Creek Supersuite, and has generally higher concentrations of TiO2, total FeO, high field strength elements and medium to have rare earth elements at equivalent SiO2 levels relative to the Mount Lamb Suite.|16-MAY-23
83161|Mulgar Granite|Structure and Metamorphism|Variably weakly to intensely foliated. Potassium feldspar phenocrysts often show no preferred foliation, but elsewhere are strongly aligned within a shear fabric. In some intervals, which represent more discrete shear zones, the primary texture has been completely obliterated by solid-state recrystallisation of quartz, mica and feldspar, resulting in a fine-grained rock (mylonite). The medium-grained phase of this unit is generally less deformed. However, given the heterogeneous distribution of deformation, this may not necessarily indicate post-tectonic emplacement of this phase.|16-MAY-23
83161|Mulgar Granite|Age reasons|SHRIMP U-Pb analysis returned overlapping igneous crystallisation ages of 1853.4 +/- 4.8 Ma, 1848.6 +/- 4.3 Ma and 1846.9 +/- 4.5 Ma for this unit (Kositcin and Cross et al., in prep). The oldest and youngest ages were obtained from undeformed and mylonitised intervals of the megacrystic phase of the unit, respectively. The intermediate age was collected from the medium- to coarse-grained phase.|16-MAY-23
83161|Mulgar Granite|Correlations|This unit is interpreted to be associated with intrusive rocks of the Tennant Creek Supersuite on the basis of appearance, age, proximity and geochemistry (Schofield and Clark et al., in prep).|16-MAY-23
83161|Mulgar Granite|Alteration and Mineralisation|Unknown.|16-MAY-23
83161|Mulgar Granite|Geophysical Expression|This unit is distinguishable in regional magnetics geophysical imagery due to its massive character and elevated magnetic susceptibility. In regional imagery of gravity data, the Mulgar Granite is characterised by a density high, suggesting that it is slightly denser than surrounding rocks of the Alroy Formation.|16-MAY-23
83161|Mulgar Granite|Geochemistry|The Mulgar Granite has overall similar geochemical trends to those of other components of the Tennant Creek Supersuite and is differentiated from the Mount Lamb Suite by its generally higher concentrations of TiO2, total FeO, high field strength elements and medium to have rare earth elements at equivalent SiO2 levels. SiO2 ranges from 65?76 wt.% with a gap between 66.5 and 74.2 wt.%. Similar to other parts of the Tennant Creek Supersuite, K2O is high (>4.48 wt.%). Slightly peraluminous composition (aluminium saturation index = 1.06?1.17). Rare earth elements patterns show enrichment of light rare earth elements relative to medium and heavy rare earth elements (normalised La/Yb = 12?19) with relatively flat medium to heavy rare earth elements (normalised Gd/Yb = 1.6?2.3) and a pronounced negative Eu anomaly (Eu/Eu* = 0.38?0.58). Whole rock Nd isotope compositions (from 3 samples) are between -3.48 and -3.96.|16-MAY-23
83161|Mulgar Granite|Defn author|A.D. Clark 24-MAR-2022.|16-MAY-23
83161|Mulgar Granite|Proposed publication|Schofield and Clark et al., (in prep). Geology of the East Tennant area, Northern Territory, journal publication.|16-MAY-23
83161|Mulgar Granite|Comments|We include this unit in the Tennant Creek Supersuite as it is lithologically similar (megacrystic granite), is the westernmost known intrusion in the East Tennant area, and has an elevated magnetic susceptibility, as distinct to all known felsic intrusives in the Mount Lamb Suite. Its geochemical characteristics are very similar to those of the Tennant Creek Supersuite. Geochemical characteristics and presence of hornblende suggest an I-type affinity, although this is somewhat at odds with peraluminous bulk rock compositions.|16-MAY-23
83161|Mulgar Granite|References|Kositcin, N., Cross A.J., et al., in prep. Geochronology of the East Tennant area, Geoscience Australia record.  **Schofield and Clark et al., (in prep). Geology of the East Tennant area, Northern Territory.  **Clark, A., Highet, L., Schofield, A., Doublier, M., 2021. Solid Geology map of the East Tennant region, dataset, Geoscience Australia.|16-MAY-23
13399|Mulluk Mulluk Volcanics|Name source|A small billabong lying immediately to the north of the Port Keats road, about 9 km west of the Daly River crossing. AMG 758770, Daly River 1:100 0000 (5070).|16-MAY-23
13399|Mulluk Mulluk Volcanics|Unit history|A not previously recognised volcanic formation. Formerly mapped as metasedimentary rocks of the Burrell Creek Formation (Malone, 1962).|16-MAY-23
13399|Mulluk Mulluk Volcanics|Type section locality|One to three kilometres SW of Daly River Mission; from AMG 810782 (near top of formation) to AMG 797771 (middle of formation) between latitude 13o45'30"S and latitude 13o46'30"S, and longitude 130o39'30"E and 130o40'30"E).|16-MAY-23
13399|Mulluk Mulluk Volcanics|Extent|Outcrop exteands over about 40 km2, in a N-S trending belt lying to the west of Daly River Mission in the SW portion of the Pine Creek (SD52-8) 1:250 000 Sheet area.|16-MAY-23
13399|Mulluk Mulluk Volcanics|Thickness range|Unknown, but probably less than 3000 m.|16-MAY-23
13399|Mulluk Mulluk Volcanics|Lithology|Dark-greyish green, conchoidally fracturing rhyolite, commonly with a spherulitic texture.|16-MAY-23
13399|Mulluk Mulluk Volcanics|Relationships and boundaries|Probably underlies Burrell Creek Formation, but contact is faulted where exposed. Probably intruded by the Wangi Basics. Unconformably overlain by Cambrian sedimentary rocks.|16-MAY-23
13399|Mulluk Mulluk Volcanics|Age reasons|Early Proterozoic|16-MAY-23
13399|Mulluk Mulluk Volcanics|Proposed publication|Dundas D.L., Edgoose C.J., Fahey G.M., and Fahey J.E., in prep - Explanatory Notes (for) Daly River (5070). Northern Territory Geological Survey 1:100 000 Geological Map Series. Northern Territory Government Printer, Darwin.|16-MAY-23
33652|Mulyati Granite|Name source|Mulyati, locality (rockhole) at 25o22'46.5"S, 129o10'26.3"E, Petermann Ranges.|16-MAY-23
33652|Mulyati Granite|Unit history|Comprises part of the Olio Gneiss of Forman (1966, 1972).|16-MAY-23
33652|Mulyati Granite|Constituents|Nil. Forms part of the Pottoyu Granite Suite.|16-MAY-23
33652|Mulyati Granite|Geomorphic expression|Low rocky hills and granite pavements.|16-MAY-23
33652|Mulyati Granite|Type section locality|Low hill 1 km west of Docker River-Wingellina road at 25o21'38.3"S, 129o9'36.1"E.|16-MAY-23
33652|Mulyati Granite|Extent|Comprises scattered low hills and outcrops south of the Pottoyu Hills encompassing most of the southern half of the Pottoyu 1:100 0000 sheet. Extent into Western Australia is not known.|16-MAY-23
33652|Mulyati Granite|Lithology|K-feldspar-rich medium to fine grained equigranular biotite granite and aplite. Contains <5% mafic minerals comprising biotite and Fe-Ti oxides.|16-MAY-23
33652|Mulyati Granite|Relationships and boundaries|Sharp intrusive relationships locally observed with porphyritic granite of Pottoyu Granite Suite. No consistent timing relationships.|16-MAY-23
33652|Mulyati Granite|Age reasons|Mesoproterozoic. Correlated with granites elsewhere in the Pottoyu Granite Suite that have U-Pb zircon ages of 1144 +/- 12 Ma (25o8'12.8"S, 129o52'22.8"E) and 1192 +/- 13 Ma (25o20'49.6"S, 129o54'15.6"E), and Rb-Sr whole rock ages of 1150 Ma (25o24'4.0"S, 130o3'49.6"E; Forman, 1972) and 1190 Ma (25o15'3.2"S, 129o39'22.9"E; Forman, 1972).|16-MAY-23
33652|Mulyati Granite|Correlations|Similar age, but geochemically distinct from the Mantarurr and Umutju Complexes and Walal Granite on Petermann Ranges.|16-MAY-23
33652|Mulyati Granite|Proposed publication|Petermann Ranges 1:250 000 geological mapsheet Explanatory Notes|16-MAY-23
33652|Mulyati Granite|Comments|Variably deformed and metamorphosed during the c.560 Ma Petermann Orogeny. Metamorphic grade is mid to upper amphibolite facies.|16-MAY-23
33652|Mulyati Granite|Category|2|16-MAY-23
33652|Mulyati Granite|Defn approved by|Beir P., Kruse P.D., Young D.N.|16-MAY-23
33652|Mulyati Granite|Proposer|Edgoose C., Cloose D., Scrimgeour I.|16-MAY-23
13518|Muriel Range Sandstone|Name source|Muriel Range, 20o46'S, 129o30'E, The Granites 1:250 000 Sheet area, NT.|16-MAY-23
13518|Muriel Range Sandstone|Unit history|Outcrop in Lucas 1:250 000 Sheet area was mapped as Phillipson Beds by Casey & Wells (1964).|16-MAY-23
13518|Muriel Range Sandstone|Type section locality|Inningarra Range, The Granites Sheet area, from 20o45'10"S, 129o38'45"E to 20o47'00"S, 129o54'30"E. Here about 450 m of mostly ;medium-grained sublithic arenite and quartz arenite dips gently south. The lower 300 m is thin bedded and characterised by pellety bedding planes. The upper 150 m is mainly medium bedded and pellety bedding planes are relatively rare.|16-MAY-23
13518|Muriel Range Sandstone|Extent|The Granites 1:250 000 Sheet are,a NT and easternmost part of Lucas 1:250 000 Sheet area, WA.|16-MAY-23
13518|Muriel Range Sandstone|Thickness range|Maximum exposed is about 450 m, in the type section.|16-MAY-23
13518|Muriel Range Sandstone|Lithology|Predominantly sandstone-sublithic arenite and quartz arenite, mainly thin-bedded; ripple marks, current bedding and pellety bedding planes common. Minor shale, siltstone and conglomerate.|16-MAY-23
13518|Muriel Range Sandstone|Relationships and boundaries|Unconformable on Archaean or Lower Proterozoic Killi Killi and Mount Charles Beds of the Tanami Complex, on Lower Proterozoic Pargee Sandstone and on unnamed granite. Stratigraphic equivalent of the Lewis Range Sandstone to the west, from which it differs in being mainly thin bedded and characterised by pellety bedding planes. Inferred to be overlain unconformably by Palaeozoic and Cretaceous units, but contacts concealed under superficial deposits.|16-MAY-23
13518|Muriel Range Sandstone|Age reasons|Probably Adelaidean.|16-MAY-23
13518|Muriel Range Sandstone|Defn approved by|Taken from xerox copy of approved defs sent by WA Sub-Committee|16-MAY-23
13518|Muriel Range Sandstone|Name first published by|Blake D.H., Hodgson I.M., Walton D.G., 1976|16-MAY-23
13528|Murphy Metamorphics|Name source|Unit name derived from Murphys Creek on the CALVERT HILLS 1:250 000 mapsheet, which rises at approximately (GDA94) 17°46’27”S 136°59’02”E . Name derivation has not been explicitly stated in prior literature.|
13528|Murphy Metamorphics|Unit history|Unit originally termed the “Murphy Metamorphics” by Smith and Roberts (1960). Name has not been revised since.|
13528|Murphy Metamorphics|Constituents|Includes two informal subunits based on lithological character: Plm1: Predominantly metamorphosed silty pelitic rocks and shale consisting of quartz, muscovite, biotite and albite with accessory zircon, tourmaline, leucoxene and opaques. Plm2: Immature meta-arenites consisting of angular quartz, lithic fragments, muscovite, biotite and albite with accessory tourmaline, zircon and opaques. The original rocks (protolith) may have been quartz- and lithic-graywackes (Ahmad and Wygralak, 1989).|
13528|Murphy Metamorphics|Geomorphic expression|Unit typically occurs as poorly exposed, ferruginised outcrop and float (Rawlings et al, 2008). Unit rarely forms topographic highs (Ahmad and Wygralak, 1989).|
13528|Murphy Metamorphics|Type section locality|No type section nominated for this unit. Instead, a reference area is nominated on the CALVERT HILLS 1:250 000 mapsheet at (GDA94) approximately 17°51’42”S 137°44’10”E (53K 790170mE 8036898mN), to the east of Fish River. Exposures of the Murphy Metamorphics in this area have been described by Gardner (1978).|
13528|Murphy Metamorphics|Extent|The unit is exposed across the southern CALVERT HILLS 1:250 000 mapsheet, and the northern and central MOUNT DRUMMOND 1:250 000 mapsheet in the Northern Territory (Ahmad and Wygralak, 1989; Rawlings et al, 2008).|
13528|Murphy Metamorphics|Thickness range|Thickness variations within the Murphy Metamorphics are unknown.|
13528|Murphy Metamorphics|Lithology|Strongly cleaved and weakly to strongly foliated quartz-albite-muscovite-biotite schists (Gardner, 1978).|
13528|Murphy Metamorphics|Depositional environment|This unit is thought to have deposited as a turbiditic succession (with some pelagic sedimentation), in a deep submarine fan or shelf, and was then subsequently metamorphosed to lower greenschist facies (Rawlings et al, 2008).|
13528|Murphy Metamorphics|Relationships and boundaries|Murphy Metamorphics form basement where they occur; therefore, there is no known lower contact. The Murphy Metamorphics are intruded in the by the Nicholson Granite. The Murphy Metamorphics are unconformably overlain by the Cliffdale Volcanics, whereas in the MOUNT DRUMMOND 1:250 000 mapsheet, the Murphy Metamorphics are overlain by the Connellys Volcanics (Ahmad and Wygralak, 1989; Rawlings et al, 2008).|
13528|Murphy Metamorphics|Identifying features|The Murphy Metamorphics can be differentiated from the overlying units by the east–west-oriented upright folding, which is absent from the overlying units (Ahmad and Wygralak, 1989; Rawlings et al, 2008).|
13528|Murphy Metamorphics|Structure and Metamorphism|Unit originally comprised a turbiditic sedimentary succession subsequently exposed to lower greenschist-facies metamorphism. Unit displays common centimetre- to decimetre-scale folding, typically as open to closed, symmetric folds with upright to inclined axes and angular hinges (Rawlings et al, 2008).|
13528|Murphy Metamorphics|Age reasons|age derived from U-Pb SHRIMP isotopic dating of igneous zircons of the Cliffdale Volcanics, which overlie the Murphy Metamorphics: Sample No: 9177.9059 - 1851 ± 3 Ma (Page et al, 2000). Crystallisation age derived from U-Pb SHRIMP isotopic dating of igneous zircons of the Nicholson Granite, which intrudes the Murphy Metamorphics: Sample No: 9177.9056 - 1856 ± 3 Ma (Page et al, 2000), Sample No: 9177.9057 - 1845 ± 3 Ma (Page et al, 2000), NTGS Sample No: CH11LJH171 / GA Sample No: 2129281 - 1846 ± 6 Ma (Kositcin et al, 2013).  Maximum depositional age derived from U-Pb SHRIMP dating of detrital zircons: Murphy Metamorphics: Sample No: CJ10 - 1870 ± 25 Ma (Hanley, 1996), Sample No: 12333 - 1852 ± 4 Ma (Hollis et al, 2010), NTGS Sample No: CH12LJH610 / GA Sample No: 2134819 - 1864 ± 5 Ma (Kositcin et al, 2014), GA Sample No: 2786176 - 1874 ± 7 Ma (Kositcin and Carson, 2019). Therefore, the potential depositional age range for the Murphy Metamorphics can be considered to extend from ca. 1870 ± 25 Ma to ca. 1852 ± 4 Ma.|09-OCT-23
13528|Murphy Metamorphics|Correlations|Possible stratigraphic equivalents for the Murphy Metamorphics include the Finniss River Group in the Pine Creek Orogen and the Warramunga Formation in the Warramunga Province (Ahmad et al, 2013).|
13528|Murphy Metamorphics|Alteration and Mineralisation|Highly ferruginised and saprolitic in places. Contains a 2–10 m-thick, laterally continuous banded iron formation at approximately (GDA94) 18°8’58’S 136°55’54E (Rawlings et al, 2008).|
13528|Murphy Metamorphics|Geophysical Expression|Weak to moderate magnetic response.|
13528|Murphy Metamorphics|Geochemistry|Two outcrop samples of the Murphy Metamorphics (GA Sample Nos: 2786176 and 2786910) were analysed for major, minor and trace element geochemistry using X-ray fluorescence (XRF) and quadrupole inductively coupled plasma mass spectrometry (ICP-MS). Sample 2786176 displays an elevated Cu concentration (361 ppm; Carson et al, 2020).|
13528|Murphy Metamorphics|Defn author|Elliot Foley, Jack Simmons, Ben Williams, Charles Verdel (Northern Territory Geological Survey), Chris Carson (Geoscience Australia) 05-DEC-2022.|
13528|Murphy Metamorphics|Comments|Note: Standard series 1: 100 000 and 1: 250 000 mapsheet names are shown in uppercase.|
13528|Murphy Metamorphics|References|Ahmad M and Wygralak AS, 1989. Calvert Hills, Northern Territory (First Edition). 1:250 000 metallogenic map series explanatory notes, Sheet SE 53-8. Northern Territory Geological Survey, Darwin, Northern Territory.  **Ahmad M, Munson TJ and Wygralak AS, 2013. Chapter 8: Murphy Province. In: Ahmad M and Munson TJ (Eds), Geology and mineral resources of the Northern Territory. Northern Territory Geological Survey Special Publication 5.  **Carson CJ, Jarrett AJM, Anderson JR, Champion DC and Henson PA, 2020. Exploring for the Future - Whole rock geochemistry data release of sedimentary and igneous rocks from the South Nicholson region, Northern Territory and Queensland. Geoscience Australia, Record 2020/02.  **Carson, C. J., Kositcin, N., Anderson, J. R., and Henson, P. A. in prep. A revised Proterozoic tectono-stratigraphy of the South Nicholson region, Northern Territory, Australia - insights from SHRIMP U-Pb detrital zircon geochronology. Australian Journal of Earth Sciences.  **Gardner CM, 1978. Precambrian geology of the Westmoreland region, northern Australia, Part III: Nicholson Granite Complex and Murphy Metamorphics. Bureau of Mineral Resources Record 1978/032.  **Hanley LM, 1996. Geochronology, mineral geochemistry, geochemistry and petrography of diamond-associated rocks in the Coanjula region, Northern Territory. BSc Hons thesis. Department of Geology and Geophysics, University of Western Australia, Perth.  **Hollis JA, Beyer EE, Whelan JA, Kemp AIS, Scherst n, A. and Greig A, 2010. Summary of results. NTGS laser U-Pb and Hf geochronology project: Pine Creek Orogen, Murphy Inlier, McArthur Basin and Arunta Region, July 2007 - May 2008. Northern Territory Geological Survey, Record 2010-001.  **Kositcin N, Beyer EE, Whelan JA, Close DF, Hallett L and Dunkley DJ, 2013. Summary of results. Joint NTGS–GA geochronology project: Arunta Region, Ngalia Basin, Tanami Region and Murphy Province, July 2011–June 2012. Northern Territory Geological Survey, Record 2013-004. **Kositcin N and Carson CJ, 2019. New SHRIMP U-Pb zircon ages from the South Nicholson and Carrara Range regions. Northern Territory. Geoscience Australia, Record 2019/09.  **Kositcin N, Whelan JA, Hallett L and Beyer EE, 2014. Summary of results. Joint NTGS–GA geochronology project: Amadeus Basin, Arunta Region and Murphy Province, July 2012-June 2013. Northern Territory Geological Survey, Record 2014-005.  **Page RW, Jackson MJ and Krassay AA, 2000. Constraining sequence stratigraphy in north Australian basins: SHRIMP U-Pb zircon geochronology between Mt Isa and McArthur River. Australian Journal of Earth Sciences 47(3), 431-459.  **Rawlings DJ, Sweet IP and Kruse PD, 2008. Mount Drummond, NT (Second Edition). 1:250 000 Geological Map Series Explanatory Notes, Sheet SE 53-12. Northern Territory Geological Survey, Darwin, Northern Territory.  **Simmons JM, Williams B, Carson, C and Verdel C, 2023a. Mount Drummond, Northern Territory 1:250 000 Geological Map, Sheet SE 53-12 (Third Edition). Northern Territory Geological Survey, Darwin, Northern Territory.  **Simmons JM, Williams B, Carson, C and Verdel C, 2023b. Mount Drummond, Northern Territory 1:250 000 Geological Map Explanatory Notes, Sheet SE 53-12 (Third Edition). Northern Territory Geological Survey, Darwin, Northern Territory.   **Smith JW and Roberts HG, 1960. Explanatory notes to the Mount Drummond 3-mile area, Northern Territory. Bureau of Mineral Resources Record 1960/070.|09-OCT-23
26787|Murra-Kamangee Granodiorite|Name source|Small, prominent hill at AMG 529306, Moyle (4969) 1:100 000 Sheet.|16-MAY-23
26787|Murra-Kamangee Granodiorite|Unit history|Previously included as part of the Litchfield Complex (Walpole and others, 1968).|16-MAY-23
26787|Murra-Kamangee Granodiorite|Type section locality|Moyle (4969) AMG 414352 (latitude 14o09'00"S, longitude 139o21'57"E) is the type area and contains the weakly to non-foliated type; and Daly River (5070) between AMG 747645 and 750605 (latitude 13o53', longitude 130o37' and latitude 13o55'15" longitude 130o37') is the reference area for the weakly to strongly foliated type.|16-MAY-23
26787|Murra-Kamangee Granodiorite|Extent|Outcrop occupies about 620 km2 in the northeast portion of the Moyle (4969) 1:100 000 Sheet area and in adjacent areas of the Daly River (5070), Greenwood (4970) and Wingate Mountains (5069).|16-MAY-23
26787|Murra-Kamangee Granodiorite|Lithology|Weakly to strongly foliated, garnetiferous tonalite with numerous xenoliths and weakly to non-foliated xenolithic biotite granodiorite, tonalite and minor adamellite.|16-MAY-23
26787|Murra-Kamangee Granodiorite|Relationships and boundaries|Intrudes and has mixed with the Hermit Creek Metamorphics. No contact exposed with the Burrell Creek Formation but age suggests an intrusive relationship.|16-MAY-23
26787|Murra-Kamangee Granodiorite|Identifying features|(stressed) quartz, plagioclase, K-feldspar, biotite (often chloritised); plagioclase usually shows sericitic alteration and myrmekite noted. Garnet nearly always present close to contacts with the Hermit Creek Metamorphics. Accessory minerals include apatite, sphene, ilmenite, magnetite, hematite, muscovite, andalusite, sillimanite, cordierite and zircon.|16-MAY-23
26787|Murra-Kamangee Granodiorite|Age reasons|Early Proterozoic - age dating by the BMR of 1840-1850 Ma (Page, R., pers. comm.)|16-MAY-23
26787|Murra-Kamangee Granodiorite|Proposed publication|Dundas D.L., Edgoose C.J., Fahey G.M., Fahey J.E., in prep - Explanatory Notes (for) Daly River (5070). Northern Territory Geological Survey 1:100 000 Geological Map Series. Northern Territory Government Printer, Darwin.|16-MAY-23
26787|Murra-Kamangee Granodiorite|Category|2|16-MAY-23
24412|Murrenja Dolerite|Name source|Murrenja Hill in the Anson (4971) 1:100 000 sheet AMG 503539 (latitude 13o05', longitude 130o23').|16-MAY-23
24412|Murrenja Dolerite|Unit history|Mapped as unnamed ?Carpentarian gabbro, diorite and dolerite on the Cape Scott 1:250 000 sheet (SD52-7) by Mendum (1972).|16-MAY-23
24412|Murrenja Dolerite|Type section locality|Type area bound by AMG 486489 (latitude 13o07'20", longitude 130o22'12"), AMG 488489 (latitude 13o07'20", longitude 130o22'19"), AMG 486487 (latitude 13o07'26", longitude 130o22'12"), AMG 488487 (latitude 13o07'26", longitude 130o22'19").|16-MAY-23
24412|Murrenja Dolerite|Extent|Occurs at and along the western side of Murrenja Hill.|16-MAY-23
24412|Murrenja Dolerite|Thickness range|Approximately 200 m.|16-MAY-23
24412|Murrenja Dolerite|Lithology|Dolerite, minor gabbro. Medium grained. Mineralogy: plagioclase, pyroxene, chlorite, opaque oxides.|16-MAY-23
24412|Murrenja Dolerite|Relationships and boundaries|Intrudes the ?Middle Proterozoic Moyle River Formation and the Early Proterozoic Wagait Granite.|16-MAY-23
24412|Murrenja Dolerite|Age reasons|Minimum age of late-Middle to Late Proterozoic.|16-MAY-23
24412|Murrenja Dolerite|Defn author|Fahey J.E., Edgoose C.J., 1986|16-MAY-23
24412|Murrenja Dolerite|Proposed publication|Fahey J.E. & Edgoose C.J., in prep - Explanatory Notes (for) Anson (4971). Northern Territory Geological Survey 1:100 000 Geological Map Series. Northern Territory Government Printer, Darwin.|16-MAY-23
24412|Murrenja Dolerite|Defn Reference|87/25679  Fully described p.11|16-MAY-23
24412|Murrenja Dolerite|Proposer|Fahey J.E., Edgoose C.J. (submitted by J.E. Fahey)|16-MAY-23
13671|Nabarlek Granite|Name source|Nabarlek exploration camp, 133o18'E, 12o19'S. Alligator River 1:250 000 Sheet area.|16-MAY-23
13671|Nabarlek Granite|Type section locality|Highly dissected hill forming central southern part of outcrop extent, 7 km from Nabarlek on a bearing of 080o, 133o22'E, 12o18'12"S. Highly altered pink-grey medium-coarse grained granite cut by quartz breccia reefs.|16-MAY-23
13671|Nabarlek Granite|Extent|6 km2, centred 8 km ENE of Nabarlek|16-MAY-23
13671|Nabarlek Granite|Lithology|Altered pink biotite granite - strongly altered to a quartz-clay rock containing some brown iron oxides. Transected by aplite dykes altered to quartz-sericite-clay rock and by approximately north-trending quartz breccias, which often form ridges. Radioactive background is generally X10 that of Nimbuwah Complex.|16-MAY-23
13671|Nabarlek Granite|Relationships and boundaries|Intrudes Nimbuwah Complex. Unconformably overlain by Carpentarian Kombolgie Formation. No contact aureole exposed - probably masked by alteration effects. Petrologically similar to, and most probably genetically associated with, the Tin Camp Granite.|16-MAY-23
13671|Nabarlek Granite|Age reasons|Approximately 1800 m.y. (Page & Needham, in prep.). Age to be taken with caution due to alteration of rock material used in dating this unit.|16-MAY-23
13671|Nabarlek Granite|Proposed publication|Journal of the Geological Society of Australia|16-MAY-23
13671|Nabarlek Granite|Name first published by|Needham R.S., Stuart-Smith P.G., 1976.|16-MAY-23
13676|Naburula Formation|Name source|The name is derived from the Naburula Hills in the central northern part of the Ngalia Basin. (Metric Co-ordinates of Naburula Hills approximately 7250-7400; 5300-5400) on the Mount Doreen SF/52-12) 1:250 000 sheet area.|16-MAY-23
13676|Naburula Formation|Type section locality|The type section (WX-6) is located in the headwaters of Patmungala Creek at 7398:5334. The type section is - TOP 0.20 m Dolomite - thin bedded, fine grained, green-grey, deeply weathered, iron stained.  0.52 m Shale - dark grey to black, well bedded.  0.20 m Dolomite - as above.  3.67 m Shale - dark grey to black, well bedded.  0.15 m Dolomite - yellow brown, fine grained, deeply weathered.   0.87 m Shale and Siltstone - yellow brown, poorly exposed.  2.10 m Diamictite - matrix poorly sorted, green-brown, angular grains of feldspar and quartz; clasts of granite, quartzite, quartz, quartz-mica schist, silicified yellow-grey siltstone, vein quartz with tourmaline, feldspar porphyry, spotted blue-grey hornfels, quartz granule grit etc. The errataics are commonly striated and faceted, and closely fractured. The diamictite shows incipient cleavage.|16-MAY-23
13676|Naburula Formation|Extent|Outcrops extend intermittently around the eastern closure of the Naburula Syncline. Diamictite overlying the Vaughan Springs Quartzite in the Vaughan Springs Syncline is referred to the Naburula Formation.|16-MAY-23
13676|Naburula Formation|Thickness range|The Naburula Formation is 8 m thick in the type section. The formation is not sufficiently well exposed to obtain any information on regional changes in thickness.|16-MAY-23
13676|Naburula Formation|Lithology|The formation comprises three dominant rock types, a basal diamictite, overlain by black shale, which is in turn overlain by interbedded dolomite and shale.|16-MAY-23
13676|Naburula Formation|Relationships and boundaries|The formation unconformably overlies Precambrian basement granite and possibly the Patmungala Beds, and is conformably overlain by the Rinkabeena Shale in the Naburula Hills. In the Vaughan Springs Syncline the formation lies with unconformity on the Vaughan Springs Quartzite and possibly the Albinia Formation but the upper contact is concealed; it is either unconformably overlain by the Mount Doreen Formation or conformably overlain by the Rinkabeena Shale.|16-MAY-23
13676|Naburula Formation|Identifying features|Reason for proposal of name: A mappable unit of thin diamictite, shale, and dolomite that has not been previously differentiated and only partly described.|16-MAY-23
13676|Naburula Formation|Age reasons|Stratigraphic relationships and regional correlations suggest that the formation is Proterozoic in age.|16-MAY-23
13676|Naburula Formation|Defn author|Preiss, W.V., Walter M.R., Coats R.P., Wells A.T., 1978|16-MAY-23
13676|Naburula Formation|Proposed publication|Geology of the Ngalia Basin. Bureau of Mineral Resources, Geology & Geophysics, Bulletin.|16-MAY-23
13676|Naburula Formation|Defn Reference|83/24047|16-MAY-23
76184|Namarrkon Amphibolite|Name source|After Namarrkon waterhole on Cahill SD 5472 (see Geoscience Australia Place Name Search: http://www.ga.gov.au/place-name/; also NT Place Names Register: http://www.ntlis.nt.gov.au/placenames/search.jsp?placeName=Namarrkon&searchType=contains&regOnly=Registered&Submit=Search, Record ID - NT 21056) GDA 94 53L 272174mE 8572007mN (-12º54'32"S 132º54'1"E) on Alligator River 1:250 000 mapsheet, Cahill 1:100 000 mapsheet, Nimbuwah Domain, Pine Creek Orogen.|16-MAY-23
76184|Namarrkon Amphibolite|Unit history|Previously mapped as Zamu Complex (in part; Stewart 1959 unpublished, as cited in Ferguson and Needham 1978, modified Bryan 1962 and Walpole 1962); or Zamu Dolerite (in part; Ferguson and Needham 1978).|16-MAY-23
76184|Namarrkon Amphibolite|Geomorphic expression|River-washed platform in drainages and low-lying outcrop elsewhere.|16-MAY-23
76184|Namarrkon Amphibolite|Type section locality|Large sill in Cahill Formation, Tin Camp Creek, Myra Falls Inlier, Alligator River 1:250 000 and Oenpelli 1:100 000 mapsheets, GDA 94 53L 316063mE 8623613mN (-12°26'43"S 133°18'28"E).|16-MAY-23
76184|Namarrkon Amphibolite|Description at type locality|~30 m-wide water-washed platform consisting of massive, homogeneous, biotite-rich meta-amphibolite.|16-MAY-23
76184|Namarrkon Amphibolite|Extent|Restricted to Oenpelli 1:100 000 mapsheet|16-MAY-23
76184|Namarrkon Amphibolite|General description|Exposed in Tin Camp Creek, Myra Falls Inlier, and also at base of Mamadawerre Sandstone of Kombolgie Subgroup of the McArthur Basin in southeast Arrarra region, Alligator River 1:250 000 and Oenpelli 1:100 000 mapsheets.|16-MAY-23
76184|Namarrkon Amphibolite|Lithology|Equigranular medium-grained mafic amphibolite with moderate schistosity, locally biotite-rich and relatively homogeneous in texture. Composed of pale-green poikilitic hornblende, aggregates of biotite (in type locality only), plagioclase and quartz.|16-MAY-23
76184|Namarrkon Amphibolite|Depositional environment|Probably originally an intrusive rock|16-MAY-23
76184|Namarrkon Amphibolite|Relationships and boundaries|Contact relationships not observed, but occurs within Palaeoproterozoic Cahill Formation and Nourlangie Schist of the Pine Creek Orogen.|16-MAY-23
76184|Namarrkon Amphibolite|Structure and Metamorphism|Amphibolite-facies metamorphism.|16-MAY-23
76184|Namarrkon Amphibolite|Age reasons|Not adequately constrained, but most likely Palaeoproterozoic as occurs within Palaeoproterozoic Cahill Formation and Nourlangie Schist.|16-MAY-23
76184|Namarrkon Amphibolite|Alteration and Mineralisation|Sericitisation of feldspar, no known mineralisation.|16-MAY-23
76184|Namarrkon Amphibolite|Geophysical Expression|Too small to be expressed on geophysical imagery.|16-MAY-23
76184|Namarrkon Amphibolite|Geochemistry|Low-Ti geochemical signature.|16-MAY-23
76184|Namarrkon Amphibolite|Defn author|LM Glass and JA Hollis, 2012|16-MAY-23
76184|Namarrkon Amphibolite|Proposed publication|Hollis JA and Glass LM, 2012. Howship and Oenpelli, Northern Territory. 1:100 00 geological map series explanatory notes, 5572, 5573. Northern Territory Geological Survey, Darwin.|16-MAY-23
76184|Namarrkon Amphibolite|References|Bryan R, 1962. Lower Proterozoic basic intrusive rocks of the Katherine-Darwin area, Northern Territory. Bureau of Mineral Resources, Australia, Record 1962/07.***Walpole BP, 1962. Mount Evelyn, Northern Territory, 1:250 000 Geological Series Explanatory Notes, SD53/5. Bureau of Mineral Resources, Australia, Canberra.***Ferguson J and Needham RS, 1978. The Zamu Dolerite: A lower Proterozoic preorogenic continental tholeiitic suite from the Northern Territory, Australia. Journal of the Geological Society of Australia 25(6), 309¿322.|16-MAY-23
24417|Namatjira Formation|Name source|Namatjira's Copper Prospect 20 km east of Areyonga Mission. The prospect is a very minor non-economic occurrence of azurite and malachite that is dispersed through the Arumbera Sandstone and the Namatjira Formation. It was also referred to as the Areyonga Copper Deposit (Bell, 1953) having been discovered by Albert Namatjira. It is labelled as Namatjira's Copper Prospect on the BMR 1:250 000 Geological Map Sheet of Henbury - Northern Territory (132o22'48", 24o07'57").|16-MAY-23
24417|Namatjira Formation|Unit history|Unit not previously recognised.|16-MAY-23
24417|Namatjira Formation|Type section locality|It occurs at 132o24'15", 24o07'56" and is 50 m thick. The base is the first occurrence of carbonate lenses in the sandstone at the top of the Arumbera Sandstone. The top is a disconformity in a zone of no outcrop between the end of its dip slope and the poorly outcropping Chandler Formation.|16-MAY-23
24417|Namatjira Formation|Extent|The unit is confined to the eastern end of the Gardiner Range Anticline in the Amadeus Basin.|16-MAY-23
24417|Namatjira Formation|Thickness range|It ranges from >100 m in the eastern nose of the anticline (132o25'38" 24o08'15") to where it pinches out 10 km to the west (132o22'12" 24o07'32"), 2 km west of Namatjira's Copper Prospect.|16-MAY-23
24417|Namatjira Formation|Lithology|It is a mixed carbonate and clastic sequence which is cyclical. The base has cycles comprising brown sandstone, buff to cream carbonate mudstone and shale which grades vertically into cycles of grey oolitic grainstone, carbonate mudstone and shale. The latter contains very minor sand stringers. The carbonate is completely dolomitised.|16-MAY-23
24417|Namatjira Formation|Relationships and boundaries|It is vertically gradational with the underlying Arumbera Sandstone and laterally interfingers with the Arumbera Sandstone to the west. It is disconformably overlain by the Chandler Formation.|16-MAY-23
24417|Namatjira Formation|Age reasons|It contains no diagnostic fauna (only ;small domal stromatolites) but is considered to be equivalent to the Arumbera Sandstone in the Gardiner Range which is thought to be Late Proterozoic to Early Cambrian in age (Hamp, 1984).|16-MAY-23
24417|Namatjira Formation|Defn author|Kennard J.M., Nicoll R.G., Owen M., 1986|16-MAY-23
24417|Namatjira Formation|Proposed publication|BMR Report|16-MAY-23
24417|Namatjira Formation|Defn Reference|86/25655  Fully described P.20|16-MAY-23
24417|Namatjira Formation|Proposer|Bradshaw John|16-MAY-23
13724|Namoona Group|Name source|The name was defined by Needham & others (1980) as containing the Masson Formation, Cahill Formation and Stag Creek Volcanics.  Owing to correlation of the upper part of the Cahill Formation with a unit belonging to another group (viz: Mundogie Sandstone of the Mount Partridge Group) the Cahill Formation is no longer placed in the Namoona Group or any other group (Needham 1984).  Recorrelation of units in the Rum Jungle area and recognition of a regional unconformity within the now no longer used "Batchelor Group" has resulted in the addition of the Celia Dolomite and Beestons Formation to the Namoona Group (Needham & Stuart-Smith, in prep.). Thus the Namoona Group as redefined contains the four formations: Beestons Formation, Celia Dolomite, Masson Formation and Stag Creek Volcanics.|16-MAY-23
13724|Namoona Group|Proposed publication|Needham & Stuart-Smith (in prep.) 'Changes in strat. Nom. And correlations.'  BMR Journal|16-MAY-23
13724|Namoona Group|Status|1|16-MAY-23
27091|Napperby Gneiss|Name source|Napperby homestead (2688, 5089), near centre of Napperby 1:250 000 Sheet area.|16-MAY-23
27091|Napperby Gneiss|Unit history|Originally called Napperby Granite by Cook & Scott (1967); Napperby Granite of Australian Geophysical (1967) included granitic rocks in Reynolds and Anmatjira Ranges as well as in Yalyirimbi Range; included in Granitic gneiss (orthogneiss) of Evans & Glikson (1969); mapped as 'Precambrian orthogneiss, granitic gneiss' by Wells & others (1971).|16-MAY-23
27091|Napperby Gneiss|Type section locality|South 20 Mile Waterhole (2834, 5069), on Day Creek 15 km east of Napperby homestead on southern side of Yalyirimbi Range: creek bed provides excellent clean rock surfaces of layered and kinked Gneiss cut by mylonitic zones.|16-MAY-23
27091|Napperby Gneiss|Extent|Entire Yalyirimbi Range in southern part of Reynolds Range and northern part of Napperby 1:100 000 Sheet areas; also in northwestern part of Aileron 1:100 000 Sheet area.|16-MAY-23
27091|Napperby Gneiss|Lithology|Medium to coarse-grained equigranular thinly layered granitic gneiss, comprising dark layers rich in biotite and light layers rich in quartz, microcline perthite, and sodic plagioclase. Layering is re-oriented along kink bands (some in conjuguate sets), strain-slip cleavage zones, and cut by sharply bounded zones up to 1 m wide of black mylonite.|16-MAY-23
27091|Napperby Gneiss|Relationships and boundaries|Intrudes Wickstead Creek beds (q.v.), Mount Freeling schist (q.v.), Mount Dunkin schist (q.v.), Nolans Dam metamorphics (q.v.), Aileron metamorphics, and Lander Rock beds in northwestern part of Aileron 1:100 000 sheet area; intrudes Mount Thomas Quartzite and Pine Hill Formation in southeastern part of Reynolds Range 1:100 000 Sheet area.|16-MAY-23
27091|Napperby Gneiss|Identifying features|The Napperby Granite of Cook & Scott (1967) and Australian Geophysical (1967) is changed to Napperby Gneiss because of the markedly layered structure of the rock. In adition a full stratigraphic definition of this unit has not hitherto been published.|16-MAY-23
27091|Napperby Gneiss|Age reasons|Preliminary Rb-Sr isotopic dates on whole rocks and muscovite are in range 1800 to 1500 m.y. (L P Black, BMR, personal communication, 1975): Middle Proterozoic.|16-MAY-23
27091|Napperby Gneiss|Proposed publication|Stratigraphic definitions in Arunta Block' - BMR Microfiche Report|16-MAY-23
27091|Napperby Gneiss|Defn Reference|82/20787|16-MAY-23
81882|Narbarloo Granite|Name source|Narbarloo North fluorite-barite-copper prospect in JINKA 1:100 000 mapsheet, Northern Territory (135.6458degreesE, 22.6889degreesS (GDA 2020)).|16-MAY-23
81882|Narbarloo Granite|Geomorphic expression|Prominent boulder hills and ranges.|16-MAY-23
81882|Narbarloo Granite|Type section locality|Eastern Mopunga Range at 135.5733degreesE 22.7098degreesS (GDA2020) in JINKA. Access via public roads and private tracks. Some off-track driving/walking might be required.|16-MAY-23
81882|Narbarloo Granite|Description at type locality|Fresh boulder granite forms a prominent ridge. It consists of an inequigranular assemblage of 5-7 mm K-feldspar grains in a finer-grained matrix of sub-mm quartz-K-feldspar-plagioclase-hornblende; K-feldspar is altered and plagioclase is sericitised. A weak compositional banding is defined by mm-scale quartz ribbons. Hornblende is about 5-10 vol%; accessory minerals are magnetite and ilmenite.|16-MAY-23
81882|Narbarloo Granite|Extent|Central-western HUCKITTA 1:250 000 mapsheet in the central and eastern Mopunga Range (Weisheit et al in prep).|16-MAY-23
81882|Narbarloo Granite|General description|Generally fresh in outcrop with a thin to very thin weathering rind that is orange to orange-brown; fresh surfaces are pink due to abundant pink K-feldspar. Onion skin weathering of boulders is noted in some outcrops. Gneissic foliation is moderately to well-developed including bands of quartz-hornblende and feldspar-quartz; locally mylonitic. Geochemical compositions are monzogranitic.|16-MAY-23
81882|Narbarloo Granite|Lithology|Fresh boulder granite forms a prominent ridge. It consists of an inequigranular assemblage of 5?7 mm K-feldspar grains in a finer-grained matrix of sub-mm quartz-K-feldspar-plagioclase-hornblende; K-feldspar is altered and plagioclase is sericitised. A weak compositional banding is defined by mm-scale quartz ribbons. Hornblende is about 5-10 vol%; accessory minerals are magnetite and ilmenite.|16-MAY-23
81882|Narbarloo Granite|Depositional environment|Genesis: Continental margin environment, either arc cordillera or back arc basin, or derived from melting of pre-existing crust that formed in a continental margin environment.|16-MAY-23
81882|Narbarloo Granite|Relationships and boundaries|Is interpreted to intrude the Deep Bore Metamorphics and is intruded by Marshall Granite.|16-MAY-23
81882|Narbarloo Granite|Identifying features|Hornblende-bearing, weakly foliated granite distinguishes this from other granites in area. Relatively fresh in outcrop compared to other granites in area.|16-MAY-23
81882|Narbarloo Granite|Structure and Metamorphism|Grain shape foliation; common moderate to well-developed gneissic foliation. Intruded prior to regional granulite- to amphibolite-facies high-thermal-gradient metamorphism.|16-MAY-23
81882|Narbarloo Granite|Age reasons|A SHRIMP 207Pb/206Pb zircon age of 1792 +/- 3 Ma is interpreted to record timing of magmatic crystallisation (Kositcin et al 2021).|16-MAY-23
81882|Narbarloo Granite|Correlations|Interpreted as co-magmatic and co-genetic with constituent units of the Molyhil, Fosters and Casper suites, Baikal Supersuite, based on similar geochemical and isotopic composition, and timing of structural fabric development.|16-MAY-23
81882|Narbarloo Granite|Alteration and Mineralisation|Locally K-feldspar-quartz altered, silicified near quartz veins. No known mineralisation.|16-MAY-23
81882|Narbarloo Granite|Geophysical Expression|Commonly associated with magnetic low responses; no characteristic gravity response; radiometric high response.|16-MAY-23
81882|Narbarloo Granite|Defn author|Anett Weisheit, Barry Reno, Eloise Beyer, Pablo Farias (NT Department of Industry, Tourism and Trade, Northern Territory Geological Survey) 3-MAY-2022.|16-MAY-23
81882|Narbarloo Granite|References|Kositcin N, Magee CW, Whelan JA and Champion DC, 2011. New SHRIMP geochronology from the Arunta Region: 2009?2010. Geoscience Australia, Record 2011-014.  **Weisheit A et al, in prep. Huckitta, Northern Territory (Third Edition). 1:250 000 geological map series explanatory notes, SF53-11. Northern Territory Geological Survey, Darwin.|16-MAY-23
37962|Narpa Group|Name source|From Narpa Bore in central-eastern HUCKITTA.|16-MAY-23
37962|Narpa Group|Unit history|Templeton Series and Georgina Series of Whitehouse (1936) in part, Selwyn Limestone of Opik (1956a:15) in part, Inca Creek Formation of Opik (1956a:18) in part, Roaring Bore Siltstone of Opik (1956a:20) in part, Pomegranate limestone of Opik (1956a:23) in part, Sandover beds (Opik 1956b) in part, Lancewood Shale Opik (1960) in part, Marqua beds (Smith and Vine 1960, Smith 1963a) in part, Arthur Creek beds (Smith 1964) in part, Meeta beds (Nichols 1964, 1966) in part, Hay River Formation (Shergold in Walter et al 1979) in part, Marqua Formation (Shergold 1985) in part.|16-MAY-23
37962|Narpa Group|Constituents|Thorntonia Limestone, Border Waterhole Formation, Arthur Creek Formation, Beetle Creek Formation, Blazan Shale, Inca Formation, Quita Formation, Roaring Siltstone, Devoncourt Limestone, Steamboat Sandstone, Kajabbi Formation, Chabalowe Formation, Arrinthrunga Formation, Georgina Limestone, Mungerebar Limestone, Selwyn Range Limestone, O'Hara Shale, Pomegranate Limestone, Gowers Formation, Currant Bush Limestone, V-Creek Limestone, Mail Change Limestone, Age Creek Formation, Split Rock Sandstone.|16-MAY-23
37962|Narpa Group|Extent|BARROW CREEK, ALCOOTA, ELKEDRA, HUCKITTA, SANDOVER RIVER, TOBERMORY, HAY RIVER, MOUNT WHELAN, northwestern BOULIA, GLENORMISTON, URANDANGI, DUCHESS, MOUNT ISA, CAMOOWEAL, LAWN HILL, eastern MOUNT DRUMMOND, southern AVON DOWNS, possibly subsurface in RANKEN.|16-MAY-23
37962|Narpa Group|Relationships and boundaries| Unconformably (Shergold and Druce 1980) or conformably and gradationally (Shergold et al 1985) overlies Riversdale Formation (provisionally of Shadow Group). Conformable and gradational on Colless Volcanics (Carter et al 1961, Carter and Opik 1961) and `Mount Hendry Formation' (de Keyser and Cook 1972:10, Rogers and Keevers 1976), the latter probably basal Thorntonia Limestone. Presumed unconformable on Mount Birnie beds, disconformable on Red Heart Dolostone and Neutral Junction Formation of Shadow Group or where these are absent, unconformable on Proterozoic rocks (Shergold and Druce 1980). Passes laterally into Wonarah beds and Camooweal Dolostone. Conformably overlain by Chatsworth Limestone of Cockroach Group or where this is absent, disconformably overlain by Tomahawk Formation and Ninmaroo Formation of Cockroach Group or Mesozoic sedimentary rocks (Casey 1959, Shergold et al 1976, 1985).|16-MAY-23
37962|Narpa Group|Age reasons|Diverse fauna (particularly of trilobites) in many units indicates early Middle Cambrian (Ordian-early Templetonian) to medial Late Cambrian (early Iverian) age (Shergold et al 1985).|16-MAY-23
37962|Narpa Group|Correlations|Gum Ridge Formation, Anthony Lagoon beds, Burton beds, Wonarah beds, Ranken Limestone, Camooweal Dolostone of central and western Georgina Basin, Top Springs Limestone of northern Georgina Basin, Chandler Limestone, Giles Creek Dolostone, Shannon Formation, Cleland Sandstone, Tempe Formation, Illara Sandstone, Deception Formation, Petermann Sandstone, Hugh River Shale, Jay Creek Limestone, lower Goyder Formation of Amadeus Basin, Bloodwood Formation of Ngalia Basin, Montejinni Limestone, Hooker Creek Formation, Lothari Hill Sandstone, Point Wakefield beds of Wiso Basin (Shergold et al 1985).|16-MAY-23
37962|Narpa Group|Comments|This is a widespread group encompassing all Middle and lower Upper Cambrian rock units in the southern and eastern Georgina Basin. It is bounded on the north and west by Wonarah beds and Camooweal Dolostone respectively, and so excludes correlative rocks of the central, western and northern Georgina Basin. A crystalline dolostone unit intersected below Wonarah beds in cored drillhole NTGS01/1 (RANKEN) may be Thorntonia Limestone or an equivalent (Kruse in prep).|16-MAY-23
29528|Narwietooma Metamorphic Complex|Name source|Narwietooma Pastoral Lease|16-MAY-23
29528|Narwietooma Metamorphic Complex|Constituents|Mount Hay Granulite, Mount Chapple Metamorphics, Bunghara Metamorphics, unnamed metamorphic rocks in the north of the Hermannsburg Sheet area (map symbol PLnx). Sliding Rock Metamorphics, Randal Peak Metamorphics, probably part of the Erontonga Metamorphics in the Alice Springs 1:250 000 Sheet area.|16-MAY-23
29528|Narwietooma Metamorphic Complex|Geomorphic expression|Several massifs on Burt Plain.|16-MAY-23
29528|Narwietooma Metamorphic Complex|Extent|Central Province of the Arunta Block, from the western part of the Alice Springs Sheet area at least as far west as the western boundary of the Hermannsburg Sheet area.|16-MAY-23
29528|Narwietooma Metamorphic Complex|Lithology|Predominantly metamorphosed rocks of igneous origin, characterised by a continuous compositional range from basic to felsic. Biotite gneiss is a characteristic rock type at amphibolite grade. Minor metasedimentary rocks, becoming more abundant in the north.|16-MAY-23
29528|Narwietooma Metamorphic Complex|Relationships and boundaries|Encloses Anburla Anorthosite, intruded by anatectic granites, Forty Five Augen Gneiss and Mount Zeil Granite.|16-MAY-23
29528|Narwietooma Metamorphic Complex|Structure and Metamorphism|Several episodes of folding. Metamorphic grade granulite, with migmatites in rocks of suitable composition, and less commonly, amphibolite. Metamorphism during the Strangways Orogeny at about 1750 Ma (Black & Shaw, 1992; Shaw & Black, 1991), southern margin overprinted by fabric of the Redbank Thrust Zone.|16-MAY-23
29528|Narwietooma Metamorphic Complex|Age reasons|Middle Proterozoic: older than 1760 Ma (age of the Forty Five Augen Gneiss, Black & Shaw, 1992), considered to have a depositional age 1760-1780 Ma (this text).|16-MAY-23
29528|Narwietooma Metamorphic Complex|Correlations|Possibly correlated with Illyabba Metamorphics.|16-MAY-23
29528|Narwietooma Metamorphic Complex|Defn author|Shaw, R.D., Warren, R.G. , 1994.|16-MAY-23
29528|Narwietooma Metamorphic Complex|Comments|Reference details missing. No evidence found that this 'definition' was ever approved.|16-MAY-23
24426|Neutral Junction Formation|Name source|Neutral Junction homestead on Home of Bullion 1:100 000 sheet (AMG GR LS957205).|16-MAY-23
24426|Neutral Junction Formation|Unit history|Erroneously mapped as Grant Bluff Formation by Smith and Milligan (1964). Upper part of Donkey Creek beds of Walter (1980).|16-MAY-23
24426|Neutral Junction Formation|Geomorphic expression|Low hills and plains. Generally poorly exposed with partial soil cover.|16-MAY-23
24426|Neutral Junction Formation|Type section locality|25-27 km southest of Neutral Junction homestead on Home of Bullion 1:100 000 sheet. Base of section at AMG GR MS158006 (latitude 21o40'30"S, longitude 134o09'08"E); top of section at AMG GR MR151970 (latitude 21o42'28"S, longitude 134o08'44"E). Approximately same position as Donkey Creek beds type section of Walter (1980).|16-MAY-23
24426|Neutral Junction Formation|Extent|Restricted to Barrow Creek 1:250 000 sheet. Mainly occurs in semi-continuous band of outcrop from 2 km southeast of Neutral Junction homestead (AMG GR LS980200) to 33 km southeast of Neutral Junction homestead (AMG GR MR170950). Isolated outcrops occur along northwestern edge of Spring Range (AMG GR MR2589), 3 km west of Ooralingie Bore (AMG GR MR1081) and several small outcrops about 7 km east of Mt Tops (AMG GR MR0189).|16-MAY-23
24426|Neutral Junction Formation|Thickness range|39 m at type section. Complete sections are restricted to this area.|16-MAY-23
24426|Neutral Junction Formation|Lithology|Reddish-brown silty and micaceous sandstone and siltstone (grey or green when fresh). Siltstone dominant in lower half of section, sandstone dominant above. Sandstone often calcareous and glauconitic, displaying ripple cross-lamination and bioturbation. Minor grey silty and glauconitic limestone. Halite pseudomorphs abundant near top of section. Trace fossils abundant below.|16-MAY-23
24426|Neutral Junction Formation|Relationships and boundaries|Overlies Early Cambrian Octy Formation with probable disconformity. Base picked at irregular contact between coarse cross-bedded sandstone (below) and poorly exposed greenish siltstone. Disconformably overlain by Middle Cambrian Chabalowe Formation. Top picked at sharp erosive contact between flaggy halite pseudomorph-bearing silty sandstone (below) and medium-grained white quartz arenite of the basal Chabalowe Formation.|16-MAY-23
24426|Neutral Junction Formation|Structure and Metamorphism|Horizontal to gently dipping, except near faults.|16-MAY-23
24426|Neutral Junction Formation|Age reasons|Early Cambrian (probably Tommotian) based on trace fossils including Phycodes pedu;m. Daily (1974) reports Early Cambrian Bemella from BMR collection BC3.|16-MAY-23
24426|Neutral Junction Formation|Correlations|Upper Arumbera Sandstone (Arumbera IV) of Amadeus Basin. May also correlate with part of upper Mount Baldwin Formation of southern Georgina Basin and part of upper Yuendumu Sandstone of Ngalia Basin.|16-MAY-23
24426|Neutral Junction Formation|Proposed publication|Barrow Creek 1:250 000 Geol. Series, Explan. Notes, NT Geological Survey|16-MAY-23
24426|Neutral Junction Formation|Category|2|16-MAY-23
24426|Neutral Junction Formation|Proposer|Haines P.W.|16-MAY-23
24427|Newhaven Shale Member|Name source|The anme of the member is derived from Newhaven Homestead in the southern part of the Ngalia Basin (7224 : 4856) on the Mount Doreen (SF/52-12) 1:250 000 Sheet area.|16-MAY-23
24427|Newhaven Shale Member|Type section locality|The type section, WX-2, is located in the eastern part of the Naburula Hills (7385 : 5337). The type section comprises a uniform sequence of red shale.|16-MAY-23
24427|Newhaven Shale Member|Extent|The Newhaven Shale lMember crops out in the eastern part of the Naburula Hills and the western part of the Wanapi Hills. Outcrops are mostly incomplete and sporadic; they are confined to the central northern part of the Ngalia Basin on the Mount Doreen 1:250 000 sheet area.|16-MAY-23
24427|Newhaven Shale Member|Thickness range|The member is 17 m thick in the type section in the Naburula Hills, 16 m of the Newhaven Shale Member was measured in a nearby section but no estimate of regional variation is possible because of its poor exposure and because its upper boundary is marked by an angular unconformity; it appears to maintain this order of thickness in the known exposures.|16-MAY-23
24427|Newhaven Shale Member|Lithology|The member consists predominantly of red shale, but in places the topmost beds are yellow brown and fawn and are probably leached beneath the unconformity.|16-MAY-23
24427|Newhaven Shale Member|Relationships and boundaries|The Newhaven Shale Member in the type section, is unconformably overlain by the Ordovician Djagamara Formation and conformably overlies the Wanapi Dolomite Member of the Mount Doreen Formation.|16-MAY-23
24427|Newhaven Shale Member|Identifying features|Reason for proposal of name: The shale is an easily reacognisable marker unit above the Wanapi Dolomite Member at the top of the Mount Doreen Formation. The shale has been described but not previously named.|16-MAY-23
24427|Newhaven Shale Member|Age reasons|Stratigraphic relationships and regional correlations suggest that the Newhaven Shale Member is Proterozoic in age. It is lithologically similar to red shale that occurs in the Pertatataka Formation in the Amadeus Basin (Wells et al., 1970).|16-MAY-23
24427|Newhaven Shale Member|Proposed publication|Geology of the Ngalia Basin. Bureau of Mineral Resources, Geology & Geophysics, Bulletin|16-MAY-23
24427|Newhaven Shale Member|Defn Reference|83/24047|16-MAY-23
24428|Newlands Volcanics|Name source|Newlands Creek in the southwest of the George Creek 1:100 0000 Sheet area, Elkedra 1:250 000 Sheet area. Headwaters of Newlands Creek drain an outcrop area of the formation. Newlands Bore is on Newlands Creek at GR 696329.|16-MAY-23
24428|Newlands Volcanics|Unit history|Corresponds to part of the Arabulja Volcanics in Blake & others (1982 - BMR Report 239), Blake & Wyche (1983 - BMR Record 1983/18), and Blake & others (1983 - BMR 83).|16-MAY-23
24428|Newlands Volcanics|Type section locality|In the eastern part of Elkedra Pound, 36 km west of Elkedra homestead (latitude 21o11'00"S, longitude 135o28'00"E) from GR 110645 to GR 115592, Elkedra 1:100 000 Sheet area, Elkedra 1:250 000 Sheet area. Here main rock types of the formation are well exposed: partly recessive pink and grey felsic lava, ignimbrite, and minor interlayered feldspathic and volcaniclastic arenite, and a bank of ridge-forming quartz arenite. A sill of porphyritic mafic granophyre, probably comagmatic with adjacent volcanics, is also present. At GR 115592 the formation is overlain by ridge-forming Coulters Sandstone. The base of the formation is not exposed in the type section, which is probably at least 1000 m thick.|16-MAY-23
24428|Newlands Volcanics|Extent|Extensive outcrops in the southeastern part of the Davenport Province, mainly in northwest Elkedra and southwest Frew River 1:250 000 Sheet areas.|16-MAY-23
24428|Newlands Volcanics|Thickness range|0 to probably more than 2000 m.|16-MAY-23
24428|Newlands Volcanics|Lithology|Generally recessive dacitic to rhyolitic ignimbrite and subordinate lava containing abundant phenocrysts of tabular sodic plagioclase up to 5 mm long +/- partly resorbed quartz, together with small ferromagnesian clots (mainly biotite aggregates), in a fine-grained, commonly dark grey, groundmass; minor bedded tuff, ashstone, agglomerate, siltstone, shale, and partly ridge-forming quartzose to feldspathic or lithic (volcaniclastic) arenite and quartzite. The volcanic rocks are commonly cleaved and much altered.|16-MAY-23
24428|Newlands Volcanics|Relationships and boundaries|Conformable on Unimbra Sandstone in southeast and conformable on and probably interfingers with Yeeradgi Sandstone in north, but basal contacts generally poorly exposed; overlain conformably and possibly disconformably by Coulters Sandstone and unconformably by Cambrian and Mesozoic? strata; intruded by sill-like bodies of porphyritic mafic granophyre probably related genetically to the volcanics.|16-MAY-23
24428|Newlands Volcanics|Age reasons|Younger than 1870 m.y. - U-Pb zircon age of volcanics within the Warramunga Group unconformably underlying the Hatches Creek Group. Older than 1640 m.y. - Rb-Sr whole-rock age of granite intruding the Hatches Creek Group.|16-MAY-23
24428|Newlands Volcanics|Defn author|Blake D.H. Stewart A.J., Sweet I.p., Wyche S., 1985|16-MAY-23
24428|Newlands Volcanics|Proposed publication|BMR Report 257|16-MAY-23
24428|Newlands Volcanics|Comments|Remarks:  Mapped separately from the Arabulja Volcanics, a stratigraphic correlative, because of geographical separation and marked lithologic differences - the Newlands Volcanics consist mainly of ignimbrite containing abundant small tabular feldspar phenocrysts, whereas the Arabulja Volcanics consist mainly of lava flows containing relatively sparse equant feldspar phenocrysts. Part of the Wauchope Subgroup of the Hatches Creek Group.|16-MAY-23
24428|Newlands Volcanics|Defn Reference|Defined 86/25362|16-MAY-23
24428|Newlands Volcanics|Proposer|Blake D.H.|16-MAY-23
24429|Ngalurbindi Orthogneiss|Name source|Ngalurbindi Hills (metric grid refereance: 220000E, 7530000N) in S part of Denison 1:100 000 Sheet area. The Hills are largely composed of Ngalurbindi Orthogneiss, plus other smaller finer-grained granite masses.|16-MAY-23
24429|Ngalurbindi Orthogneiss|Type section locality|Point 206700E, 7530700N, 7 km SW of 'Mt Allan' HS, in SW part of Denison 1:100 000 Sheet area. Good clean exposure on N side of hill, showing c.gr. Gneissic granite approaching augen granite, c large xenoliths of biotite gneiss.|16-MAY-23
24429|Ngalurbindi Orthogneiss|Extent|Ngalurbindi Hills, in S part of Denison 1:100 000 Sheet area and SW part of Reynolds Range 1:100 000 Sheet area.|16-MAY-23
24429|Ngalurbindi Orthogneiss|Lithology|Mainly coarse porphyritic gneissic granite to augen granite (some even-grained coarse granite) in W and along N side of Ngalurbindi Hills. Along S side, coarse gneissic granite grades eastwards to medium-grained gneissic granite, similar to Napperby Gneiss farther E in Yalyirimbi Range.|16-MAY-23
24429|Ngalurbindi Orthogneiss|Relationships and boundaries|Intrudes slate, schist (assigned to Lander Rock beds or Pine Hill Formation) and hematitic porphyry in area immediately west of Rocco Bore. Is intruded by Wangala Granite (q.v.)|16-MAY-23
24429|Ngalurbindi Orthogneiss|Identifying features|Reason for proposed name: A distinctive and voluminous gneissic granite mass easily distinguished from surrounding rock-types.|16-MAY-23
24429|Ngalurbindi Orthogneiss|Age reasons|Not isotopically dated. Probably same age as neighbouring Napperby Granite which is dated at 1800-1500 m.y. on muscovite and whole rock Rb-Sr (L P Black, BMR personal communication, 1975).|16-MAY-23
24429|Ngalurbindi Orthogneiss|Proposed publication|1. 'Geology of NW Arunta Block' - BMR Publication.  2. 'Stratigraphic definitions in Arunta Block' - BMR Microfiche Report.|16-MAY-23
24429|Ngalurbindi Orthogneiss|Defn Reference|80/20787|16-MAY-23
24429|Ngalurbindi Orthogneiss|Proposer|Stewart A.J.|16-MAY-23
22544|Ngilipitji Conglomerate Member|Name source|Ngilipitji community (AMG NF568023), Blue Mud Bay 1:250 000 map sheet area.|16-MAY-23
22544|Ngilipitji Conglomerate Member|Unit history|Previously undifferentiated Yarrawirrie Formation. Plumb and Roberts (1992) mention a local basal conglomerate to the Yarrawirrie Formation but did not differentiate it as a member.|16-MAY-23
22544|Ngilipitji Conglomerate Member|Geomorphic expression|Varies from recessive and valley-forming, to being expressed as low hills.|16-MAY-23
22544|Ngilipitji Conglomerate Member|Type section locality|At latitude 13o22'S, longitude 135o34'30"E along the south bank of an unnamed creek in the Blue Mud Bay 1:250 000 scale map sheet area. Base at AMG NF624226. The actual point of contact is covered here, but can be fairly closely constrained. Top at AMG NF622221 where there is a gradational contact with the upper part of the Yarrawirrie Formation at the base of a cliff above the creek.|16-MAY-23
22544|Ngilipitji Conglomerate Member|Extent|Crops out mainly on the Blue Mud Bay 1:250 000 scale map sheet area, where it is exposed from the area of th Ngilipitji airstrip, north to the northern margin of the sheet, and extends on to the southern edge of the Arnhem Bay 1:250 000 scale map sheet area around longitude 135o45'E.|16-MAY-23
22544|Ngilipitji Conglomerate Member|Thickness range|Maximum thickness of 200 m a few kilometres southwest of the type section. May rapidly pinch out along strike.|16-MAY-23
22544|Ngilipitji Conglomerate Member|Lithology|Polymict pebble and cobble conglomerate with a lithic sandstone matrix and some interbeds of poorly sorted lithic sandstone. Weakly bedded and cross-bedded in places. Clasts are rounded to angular and dominantly composed of sandstone but include carbonates, mudstone and chert. Chert becomes more common in northern outcrops and dominates in places. Flat clasts impricated.|16-MAY-23
22544|Ngilipitji Conglomerate Member|Depositional environment|Probably a high energy marginal marine deposit.|16-MAY-23
22544|Ngilipitji Conglomerate Member|Relationships and boundaries|Local basal member of the Yarrawirrie Formation (defined by Plumb and Roberts, 1992). Unconformably overlies several lower formations of the Balma Group (Zamia Creek Siltstone, Conway Formation, Vaughton Siltstone). Base taken at erosive contact below conglomerate or coarse sandstone. Overlain gradationally by the upper part of the Yarrawirrie Formation. Boundary picked above the last significant pebbly or conglomeratic bed.|16-MAY-23
22544|Ngilipitji Conglomerate Member|Age reasons|A SHRIMP U-Pb zircon maximum age of 1620 + 21 Ma has been determined for tuffaceous rocks in the upper part of the Yarrawirrie Formation (Pietsch and others, 1994).|16-MAY-23
22544|Ngilipitji Conglomerate Member|Correlations|Haines (1994) considers the base of the Ngilipitji Conglomerate Member to define a major sequence boundary possibly correlative of the unconformity at the base of the Lynott Formation (McArthur Group) and the contact at the base of the Darwarunga Sandstone (Habgood Group).|16-MAY-23
22544|Ngilipitji Conglomerate Member|Defn author|Haines P.W.|16-MAY-23
22544|Ngilipitji Conglomerate Member|Proposed publication|Blue Mud Bay 1:250 000 Geological Map Series, Northern Territory, National Geoscience Mapping Accord, Explanatory Notes, SD 53-7 (Haines and others, in prep.).|16-MAY-23
22544|Ngilipitji Conglomerate Member|Category|2|16-MAY-23
22544|Ngilipitji Conglomerate Member|Defn approved by|Brakel A.T., Haines P.W.|16-MAY-23
22544|Ngilipitji Conglomerate Member|Proposer|Haines P.W.|16-MAY-23
22544|Ngilipitji Conglomerate Member|Reserved? Yes/No|Yes|16-MAY-23
83787|Ngwrratiji Basalt|Name source|Little Lake Surprise (Ngwrratiji), an ephemeral freshwater lake located ~3.5 km west of type locality in vicinity of (GDA94) 19.81071°S 133.95464°E (53K 390515mE 7809127mN) in Kelly 1:100,000 mapsheet, Northern Territory.|
83787|Ngwrratiji Basalt|Unit history|Replacing an invalid name (Bluebush basalt used in Farias et al 2022a, b, c). Invalid name ‘Bluebush basalt’ could be confused for / or be included in Bluebush Metamorphics (Strat No 75904).|
83787|Ngwrratiji Basalt|Type section locality|No type section nominated. Described entirely from drill core (drillhole TDD01; Page 2010), which is nominated as reference section. Drillhole collar location: (GDA94) 19°48'19"S 133°59'8"E (19.8051561°S 133.985527°E); in Kelly 1:100,000 mapsheet, Northern Territory. Drill core is currently stored at the Core Facility of the Northern Territory Geological Survey in Darwin (38 Farrell Crescent, Winnellie NT 0820).|08-SEP-23
83787|Ngwrratiji Basalt|Description at type locality|Chlorite-epidote-carbonate-K-feldspar-altered, porphyritic actinolite basalt. Dark-green porphyritic basalt with euhedral actinolite, hornblende, augite and albite phenocrysts in a fine-grained amphibole-plagioclase-chlorite groundmass.|02-OCT-23
83787|Ngwrratiji Basalt|Extent|Real extent is unknown. However, the ~500 m thick basalt is associated with a large ~10×10 km gravity high interpreted to be originated by undercover mafic rocks (Farias et al 2022a).|
83787|Ngwrratiji Basalt|General description|Porphyritic actinolite basalt with E-MORB composition, associated with a gravity high anomaly.|
83787|Ngwrratiji Basalt|Thickness range|Drillhole TDD01 (Page 2010) was collared in Quaternary sediments (~5 m thickness). Basalt was intersected from ~5 m to a downhole depth of 151.4 m. Basalt is in faulted contact with an undefined interbedded sandstone/siltstone unit, which continues until 342.5 m. Basalt continues from 342.5 m to end of hole (701.7 m). True thickness remains unknown as end of hole is within unit (Farias 2021).|08-SEP-23
83787|Ngwrratiji Basalt|Lithology|Chlorite–epidote– carbonate–K-feldspar-altered, porphyritic actinolite basalt. Texture is clearly porphyritic with 45–50%, 0.5–2 mm, fresh euhedral actinolite phenocrysts and 35–40%, 0.5–1 mm, relatively fresh euhedral albite phenocrysts in a fine-grained amphibole–plagioclase–chlorite groundmass. Most actinolite phenocrysts have patchy cores of hornblende or augite. Locally, there are interstitial and patchy chlorite, epidote (with allanite cores) and calcite zones with iron–nickel–chromium sulfide mineralisation; and late calcite–k-feldspar veinlets that overprint mineralisation. Apatite and titanite occur as accessory phases in basalt groundmass and in chlorite–epidote–sulfide-rich domains (Farias et al 2022a).
There are two cumulate zones associated with nickel–copper mineralisation at 347–349.1 m and 368.1–374.3 m. Petrology of cumulates suggests a chlorite–talc–carbonate-altered mafic/ultramafic rock. Chlorite and talc domains form a phlebitic texture. Chlorite has up to 3–5%, 0.05–0.1 mm hematite inclusions. Fine-grained carbonate and talc form finely disseminated patches in the chlorite groundmass and form up to 50% of the mineralised sections. Carbonate–talc-rich lenses are probably total alteration of magnesium minerals. Pyrite agglomerates are in obliterated and strained carbonate-rich lenses (Farias 2021).|
83787|Ngwrratiji Basalt|Depositional environment|Interpreted as formed during a ca 1.76 Ga extensional event that could represent a continuation of the ca 1.82–1.80 Ga Murchison Event (Farias et al 2022c).|
83787|Ngwrratiji Basalt|Relationships and boundaries|Not exposed. Basalt is in faulted contact with an undefined siliciclastic sedimentary unit in drill core. Other contact relationships are unknown.|08-SEP-23
83787|Ngwrratiji Basalt|Identifying features|Distinctive composition and age. Whole-rock geochemistry suggests an enriched mid-oceanic ridge basalt (E-MORB) composition, different to other magmatic arc-like mafic rocks in the region (see Donnellan 2013). Similarly, the age of the basalt (ca 1.76 Ga) is unrelated to any known magmatic event in the Warramunga Province.|
83787|Ngwrratiji Basalt|Structure and Metamorphism|Metamorphic foliation that varies in intensity along drillhole is defined by strained amphibole, carbonate and aligned phyllosilicates. This foliation overprints carbonate alteration veins in cumulate layer. Epidote ± chlorite ± actinolite indicate a low-temperature metamorphic assemblage. Actinolite–hornblende after augite suggests metamorphic retrogression.|
83787|Ngwrratiji Basalt|Age reasons|Laser ablation inductively coupled plasma mass spectroscopy (LA–ICP–MS) in situ apatite geochronology age of 1758 ± 78 Ma (2σ) is interpreted as the age of orthomagmatic mineralisation and a proxy for igneous crystallisation age (Farias et al 2022a).|
83787|Ngwrratiji Basalt|Correlations|Potentially represents a late stage of extensional Murchison Event (Donnellan 2013). Mafic magmatism of Murchison Event is represented by dolerite, gabbro and monzodioritic sills that intrude Ooradidgee and Tomkinson Creek groups, and is potentially associated with flood basalts of Kudinga Basalt (Davenport Province), and Whittington Range Volcanics (Tomkinson Province; Donnellan 2013).|
83787|Ngwrratiji Basalt|Alteration and Mineralisation|Alteration of basalt is characterised by sulfide-bearing carbonate veins and breccias, Mg-chlorite and talc (Farias 2021). Nickel mineralisation was reported for TDD01 drillhole by Page (2010): 1 m at 2100 ppm Ni from 369 m, and 7 m at 2185 ppm Ni, including 1 m at 3200 ppm Ni from 376 m. Petrology of samples from this basalt reveal that pentlandite is strongly associated with pyrrhotite, typically with flame-like exsolution textures within pyrrhotite. Pentlandite is also found as disseminated grains or aggregates with chalcopyrite and pyrite. Sphalerite and galena are also observed in contact with pyrrhotite. The association of nickel–copper–iron sulfides with lead–zinc sulfides is not clear. Although sphalerite is in contact with pyrrhotite (and pentlandite), there are multiple examples of galena–sphalerite-bearing carbonate veinlets overprinting the dominant foliation in the basalt; this suggests a post-deformation base metals mineralising event. In summary, the sulfide assemblages suggest an early orthomagmatic nickel–copper sulfide mineralisation overprinted by an epigenetic base metals mineralisation.
Drill core from TDD01 has been analysed with the HyLogger™ by NTGS (Smith and Huntington 2010);Hylogger results support petrological studies.|
83787|Ngwrratiji Basalt|Geophysical Expression|Associated with a gravity high in Bluebush area (Page 2010, Farias et al 2022b) and a moderate-high magnetic response.|
83787|Ngwrratiji Basalt|Geochemistry|E-MORB basalt. Whole-rock Sm–Nd isotopic data yield positive εNd(t) values (0.98–2.30) and two-stage depleted mantle model ages ranging between 2.22–2.12 Ga, implying juvenile rocks were derived from a Palaeoproterozoic mantle-sourced crust (Farias et al 2022b). REE pattern is characterised by overall negative slopes (both, LREE and HREE) and a negligible Eu anomaly.|
83787|Ngwrratiji Basalt|Defn author|Pablo Farias (05-SEP-2023)|
83787|Ngwrratiji Basalt|Comments|Revision of previous invalid / informal name.|
83787|Ngwrratiji Basalt|References|Donnellan N, 2013. Chapter 9 – Warramunga Province: in Ahmad M and Munson TJ (compilers). ‘Geology and mineral resources of the Northern Territory’. Northern Territory Geological Survey, Special Publication 5.  **Farias PG, 2021. Lithology and petrology of drillhole TDD001, Bluebush area, Warramunga Province. Northern Territory Geological Survey, Record 2021-006.  **Farias PG, Reno BL, Whelan JA and Danyushevsky LV, 2022a. Summary of results. Laser ablation ICP–MS in situ apatite geochronology of the base metal and copper–gold–bismuth deposits of the Rover field, and the copper–nickel mineralisation of the Bluebush area, Warramunga Province. Northern Territory Geological Survey, Record 2022-003.  **Farias  PG, Whelan  JA, Reno  BL, Cross A, Huston  D, Maas R, Mernagh T and Danyushevsky L, 2022b. Mineral systems of the Rover field: in ‘Annual Geoscience Exploration Seminar (AGES) Proceedings, Alice Springs, Northern Territory, 5-6 April 2022’. Northern Territory Geological Survey, 127-146.  **Farias PG, Whelan JA, Waltenberg K, Brotodewo A, Clark C, Armstrong R, Evans NJ and McDonald BJ, 2022c. Summary of results. Zircon isotopic and trace element data from the Rover field, Warramunga Province. Northern Territory Geological Survey, Record 2022-009.  **Page T, 2010. Territory Uranium Company LTD. Tennant Creek Bluebush ‘Iron Oxide Copper Gold exploration in covered terrain (EL24966). Northern Territory Geological Survey, Open File Company Report CR2010-0203.  **Smith BR and Huntington JF, 2010. Drillhole report for TDD01, Tennant Region, Northern Territory: National Virtual Core Library NTGS Node: HyLogger 2-7. Northern Territory Geological Survey, Record 2010-008.|02-OCT-23
83787|Ngwrratiji Basalt|Apprdate|05-SEP-2023|02-OCT-23
83787|Ngwrratiji Basalt|Defn approved by|Tim Munson NTGS|
83787|Ngwrratiji Basalt|Proposer|Pablo Farias (NT Department of Industry, Tourism and Trade, Northern Territory Geological Survey)|
83787|Ngwrratiji Basalt|Resdate|11-JAN-2023|
83787|Ngwrratiji Basalt|Reserved? Yes/No|Yes|
83787|Ngwrratiji Basalt|State(s)|NT|
83787|Ngwrratiji Basalt|Status|Formal|
83787|Ngwrratiji Basalt|Unit name|Ngwrratiji Basalt|
14123|Nicholson Granite Complex|Name source|From the Nicholson River in the Calvert Hills and Westmoreland 1:250 000 Sheet areas.|16-MAY-23
14123|Nicholson Granite Complex|Unit history|The name replaces Nicholson Granite and Norris Granite. The name Nicholson Granite Complex has been coined to avoid the continuing confusion over the names it replaces, namely the Nicholson and Norris Granites. Carter (1959) assigned the name Nicholson Granite to adamellite and granite which intrude acid volcanics (the Cliffdale Volcanics) in the Westmoreland 1:250 000 Sheet area, Queensland. Both the granites and acid volcanics crop out more extensively in the Calvert Hills Sheet area, Northern Territory, which was examined by Roberts, Rhodes & Yates (1963). They recognised 2 granites - The Nicholson Granite, which they considered to be older than the Cliffdale Volcanics, and the Norris Granite, which they considered to be younger than the volcanics. isotopic age determinations seemed to bear this out, but contacts were poorly exposed and few conclusions could be drawn from field relations. During detailed mapping parts of the Westmoreland and Calvert Hills Sheet areas in 1973 and 1974, Gardner (in prep.) recognized 5 major phases and 2 minor phases of granite, only one of which could not be shown to have intruded the volcanics. This is the oldest phases, BGN1, and it occupies only a small part of the area previously mapped by roberts, Rhodes & Yates (1963) as Nicholson Granite. All other phases intrude the volcanics and would, under Roberts and others' nomenclature, have been designated Norris Granite. This seemed unsatisfactory, since (A) Nicholson Granite had been used by Carter (1959) for these granites, and (b) it had not been shown that BGN1 was a seperate granite, unrelated to the other phases. The Name Nicholson Granite Complex was therefore proposed to embrace all the granites in the area.|16-MAY-23
14123|Nicholson Granite Complex|Type section locality|Type Area:  Virtually all relations between the seven mapped phases can be recognised between the Fish River and the Qld-N.T. border, in the Calvert Hills Sheet area. This is therefore nominated as the type area.|16-MAY-23
14123|Nicholson Granite Complex|Extent|An east-northeast-trending belt occupying over 600 km ^2 in the southeastern Calvert Hills Sheet area (N.T.), and southwestern Westmoreland Sheet area (Qld.).|16-MAY-23
14123|Nicholson Granite Complex|Lithology|The rocks vary from coarse, porphyritic hornblende-biotie adamellite, with xenoliths, through biotite granite, granodiorite and porphyritic diorite, to leucocratic granite and microgranite. Quartz-muscovite greisen is a marginal phases in some areas.|16-MAY-23
14123|Nicholson Granite Complex|Relationships and boundaries|The granite intrudes the Murphy Metamorphics and Cliffdale Volcanics.|16-MAY-23
14123|Nicholson Granite Complex|Age reasons|Phase BGN1, which cannot be shown to intrude the Cliffdale Volcanics, is in contact with a banded recrystallized rock which Mitchell (1975) assigned to the Cliffdale Volcanics. If the rock was recrystallized by intrusion of BGN1, then clearly there is no granite older than all of the volcanics. BGN1 has yielded a Rb-Sr isotopic age of about 1840 Ma (McDougall et al., 1965; A.W. Webb, Amdel. Rep. AN1814/73, Unpubl.) but phase BGN3-4, which intrudes several phases of granite, and the Cliffdale Volcanics, has yielded an isotopic age of 1860-103 Ma (A.W. Webb, Amdel Rep. An 2850/75, unpubl.). Other phases of granite have yielded ages as young as 1738 Ma (Webb, Amdel Rep. AN2850/75). An age of 1773 +/- 24 Ma from an isochron representing samples from BGN2 and BGN5 is virtually identical to the age of 1770 +/- 20 Ma for the Cliffdale Volcanics.|16-MAY-23
14123|Nicholson Granite Complex|Defn author|Sweet, I., Gardner, C.M. 1981.|16-MAY-23
14123|Nicholson Granite Complex|Comments|Isotopic age determinations suggest that some of the granites in the area are older than some of the Cliffdale Volcanics. Although it seems likely that the granites may have been intruded during a period of nearly 100 Ma, it is possible that the volcanics were also extruded over a long period. Many of the volcanics are ignimbritic and have not been dated. Future zircon dating may help resolve the issue, but in the meantime the name Nicholson Granite Complex is to be applied in place of Nicholson and Norris Granites.|16-MAY-23
14123|Nicholson Granite Complex|References|Carter, E.K., 1959 - Westmoreland Queensland - 4 mile Geological Series. BMR explan. Notes SE/54-5. **Gardner, C.M., in prep. - Precambrian geology of the Westmoreland region, northern Australia. Part 3: The Nicholson Granite Complex and Murphy Metamorphics. BMR Rec. (Unpubl.). **McDougall, I., Dunn, P.R., Compston, W., Webb, A.W.,Richards, J.R., & Bofinger, V.M., 1965 - Isotopic age determinations on precambrian rocks of the Carpentaria region, Northern Territory, Australia. J. geol. Soc. Aust., 12, 67-90. **Mitchell, J.E. 1976 - Precambrian geology of the Westmoreland region, northern Australia. part 2: The Cliffdale Volcanics. BMR Rec. 1976/34 (Unpubl.). **Roberts, H.G., Rhodes, J.M., & Yates, K.R., 1963 - Calvert Hills, Northern Territory - 1:250 000 Geological Series. BMR explan. Notes SE/53-8.|16-MAY-23
25343|Nimbuwah Complex|Type section locality|Migmatite rock pavement intruded by Maningkorrirr Phonolite, AMG LG 457546 (latitude 12o10'S, longitude 13o35'E).|16-MAY-23
25343|Nimbuwah Complex|Extent|Forms a roughly circular mass about 80 km across between Aurari Bay and the headwaters of the Goomadeer River which is extensively covered by a thin veneer of Mesozoic sediments especially near the coast, and in the Caramel East and Myra Falls Inlier between about 20 and 45 km south of Nabarlek.|16-MAY-23
25343|Nimbuwah Complex|Lithology|Rock types: granitic, granodioritic, tonalitic and leucogranitic banded and otherwise migmatitic rocks, the phases displaying a wide range of interpenetration fabrics which are generally more apparent in the south and central parts.|16-MAY-23
25343|Nimbuwah Complex|Relationships and boundaries|Unconformably overlain by Kombolgie Formation intruded by Oenpelli Dolerite. Contacts with Myra Falls Metamorphic not exposed.|16-MAY-23
25343|Nimbuwah Complex|Age reasons|Early Proterozoic. Model age of intrusion of precursor granite about 1870 Ma (Page & others 1980). Age of metamorphism (migmatisation) about 1800 Ma (Page & others 1980).|16-MAY-23
25343|Nimbuwah Complex|Defn author|Needham, R.S. ~1984|16-MAY-23
25343|Nimbuwah Complex|Proposed publication|Needham, 1984 - Nabarlek region N.T. BMR 1:100 000 map commentary|16-MAY-23
25343|Nimbuwah Complex|Comments|Definition: The name was first used by Rix (1965) and re-defined by Needham & others (1974), who recognised four zones. The zones were, from the centre of the unit outwards, the Granitoid Core, Migmatite Zone, Lit-par-lit Gneiss Zone, and Transitional Zone, and were all thought to represent progressive migmatisation of metasediments, to granitoid rocks in the centre. Page & others (1980) determined a meta-igneous origin for the Granitoid Core and Migmatite Zones, so Needham (1984a and b) separated them from the demonstrably metasedimentary Lit-par-lit Transitional Zones, for which he re-instated the name Myra Falls Metamorphics.  Needham and Stuart-Smith (in press) describe the variation from migmatitic to homogeneous granitoid, implicit in the distinction between the Migmatite Zone and Granitoid Core, as apparent only; the entire granitoid mass of the complex is migmatitic, but in places - particularly in the north - less compositional difference between leucosome and melanosome render the migmatitic nature of the rocks difficult to observe. Consequently no subdivision of the complex is now recommended, except for unnamed tonalites differentiated in the south and some locally distinct granite bodies (Needham 1984a and b).  Changed parts of the definition are as follows: Distribution, Type area, Rock Types, Relationships, Age evidence.|16-MAY-23
25343|Nimbuwah Complex|References|NEEDHAM, R.S. 1984a. Nabarlek region. Bureau of Mineral Resoures 1:100 000 map commentary. ** NEEDHAM, R.S. 1984b. Alligator River, NT 1:250 000 geological series (2nd edition).  Bureau of Mineral Resoures, Australia. Explanatory Notes.  **NEEDHAM, R.S., Smart, P.G., Watchman, A.L. 1974. A re-interpretation of the geology of the Alligator Rivers Uranium Field. Search 5, 397-399. **NEEDHAM, R.S., Stuart-Smith, P.G. 1984. Revised stratigraphic nomenclature and correlation of Early Proterozoic rocks of the Darwin - Katherine region, Nothern Territory. BMR Journal 9(3) 233-238.   **PAGE, R.W., Compston, W., Needham, R.S. 1980 Geochronology and evolution of the late- Archaean basement and Proterozoic rocks in the Alligator Rivers Uranium Field, Northern Territory. IN:  Ferguson J., Goleby, A.B. (eds), 'Uranium in the Pine Creek Geosyncline'. International Atomic Energy Agency, Vienna. Proceedings. 39-68.  **RIX, P. 1965 Milingimbi N.T. 1:250 000 geological series. Bureau of Mineral Resources, Australia, Explanatory Notes|16-MAY-23
75717|Njibinjibinj Gneiss|Name source|After Njibinjibinj locality, ca 37 km east of Oenpelli; ALLIGATOR RIVER; OENPELLI, Nimbuwah Domain, Pine Creek Orogen, western Arnhem Land, Northern Territory.|16-MAY-23
75717|Njibinjibinj Gneiss|Unit history|Previously known as part of the Myra Falls Metamorphics. The name 'Myra Falls Metamorphics' was first introduced by Dunn (1962) to describe metamorphic rocks in the Oenpelli area (now often referred to as Kunbarllanjnja or Gunbalanya) which were then considered to be Archaean. Subsequent work by Needham et al (1974) suggested these rocks were Palaeoproterozoic. The name 'Myra Falls Metamorphics' is abandoned, as it is now known to comprise components of the Palaeoproterozoic Kakadu Group, Cahill Formation and Neoarchaean gneissic basement (Hollis et al 2009b).|16-MAY-23
75717|Njibinjibinj Gneiss|Geomorphic expression|Isolated, low-lying, weathered boulders.|16-MAY-23
75717|Njibinjibinj Gneiss|Type section locality|Small exposure in northeast Myra Falls Inlier, about 40 km east-southeast of Oenpelli. ALLIGATOR RIVER, OENPELLI. Grid reference: GDA94 53L 327668mE 8625341mN ( 12°25'49''S 133°24'52''E)|16-MAY-23
75717|Njibinjibinj Gneiss|Description at type locality|Isolated, low-lying, weathered boulder exposures at base of talus slope derived from the adjacent Mamadawerre Sandstone (Kombolgie Subgroup).|16-MAY-23
75717|Njibinjibinj Gneiss|Extent|Minor exposures at type locality. Subsurface extent is unknown.|16-MAY-23
75717|Njibinjibinj Gneiss|Thickness range|Unknown due to poor exposure|16-MAY-23
75717|Njibinjibinj Gneiss|Lithology|Granitic gneiss with strong haematitic and chloritic alteration. Minerals include sericitised plagioclase, K-feldspar, quartz, rare muscovite and opaque oxides.|16-MAY-23
75717|Njibinjibinj Gneiss|Depositional environment|Genesis: Metamorphosed granitic intrusion.|16-MAY-23
75717|Njibinjibinj Gneiss|Relationships and boundaries|Njibinjibinj Gneiss is the oldest recognised component of Archaean basement in Nimbuwah Domain and is coeval with the 2674 Ma Woolner Granite of Central Domain (Glass et al 2009; Glass et al 2010; Carson et al 2010). Based on the SHRIMP U-Pb age of a single recrystallised zircon rim of 2508 +/-8 Ma, Njibinjibinj Gneiss is thought to have experienced metamorphism at this time, which may be related to the intrusion of the ca 2530-2510 Ma Kukalak Gneiss and 2520 Ma Nanambu Complex (Hollis et al 2009c). Njibinjibinj Gneiss forms tectonic basement to Palaeoproterozoic Kudjumarndi Quartzite (Kakadu Group) in northeastern Myra Falls Inlier. The exact nature of unit boundary with the structurally overlying Kudjumarndi Quartzite is not possible to define, owing to poor exposure. However, Njibinjibinj Gneiss is inferred to have been thrust northwest against Kudjumarndi Quartzite, based on outcrop-scale northwest-vergent isoclinal folds and thrusts in Kukalak Gneiss and Cahill Formation that are locally observed in outcrop and in drill core. Detailed stratigraphic relationships are described in Hollis et al (2009c). Haematitic and chloritic alteration is attributed to localised, late brittle thrusting of Njibinjibinj Gneiss and structurally overlying Palaeoproterozoic metasedimentary rocks northwest over younger Kombolgie Subgroup. Consistent with this, adjacent outcrops of unconformably overlying Mamadawerre Sandstone show brecciation, silicification and brittle deformation of primary bedding structures.|16-MAY-23
75717|Njibinjibinj Gneiss|Identifying features|Njibinjibinj Gneiss is distinguished from younger Palaeoproterozoic Nimbuwah granitoids by distinctive metamorphic fabrics, e.g., a moderately developed gneissosity, and by a distinctive geochemical signature characterised by depletion in heavy rare earth elements relative to light rare earth elements (Glass et al 2009).|16-MAY-23
75717|Njibinjibinj Gneiss|Structure and Metamorphism|Amphibolite-facies Njibinjibinj Gneiss preserves a moderately developed gneissic compositional layering, defined by quartzo-feldspathic and biotite-rich mm- to cm-scale layers, and by feldspars elongated within fabric. Local isoclinal folds of gneissosity are present (Hollis et al 2009c).|16-MAY-23
75717|Njibinjibinj Gneiss|Age reasons|U-Pb SHRIMP zircon age of 2671 +/- 3 Ma (Hollis et al 2009a, c, Carson et al 2010), interpreted to represent primary magmatic crystallisation age of granitic protolith|16-MAY-23
75717|Njibinjibinj Gneiss|Correlations|Temporal correlative of Woolner Granite (2674 +/- 3 Ma, Glass et al 2009, Glass et al 2010, Carson et al 2010; 2675 +/- 28 Ma, Williams and Compston 1983) in Central Domain of Pine Creek Orogen.|16-MAY-23
75717|Njibinjibinj Gneiss|Alteration and Mineralisation|Strong haematitic and chloritic alteration.|16-MAY-23
75717|Njibinjibinj Gneiss|Geophysical Expression|No distinctive geophysical expression.|16-MAY-23
75717|Njibinjibinj Gneiss|Geochemistry|Has a distinctive geochemical signature typical of Archaean rocks, characterised by depletion in heavy rare earth elements relative to light rare earth elements (Glass et al 2009).|16-MAY-23
75717|Njibinjibinj Gneiss|Defn author| JA Hollis and LM Glass, NTGS,   03-NOV-2010|16-MAY-23
75717|Njibinjibinj Gneiss|References|**CARSON CJ, Hollis JA, Glass LM, Close DF, Whelan JA and Wygralak A, 2010. Summary of results. Joint NTGS-GA geochronology project: East Arunta Region, Pine Creek Orogen and Murphy Inlier, July 2007  - June 2009. Northern Territory Geological Survey, Record 2010-004.    **DUNN PR, 1962. Alligator River, NT. 1:250,000 geological series explanatory notes, D/53-1. Bureau of Mineral Resources, Australia, Canberra.    **GLASS LM, Hollis JA and Carson CJ, 2009. Geochemical and isotopic discrimination methods for Neoarchaean and Palaeoproterozoic rocks in western Arnhem Land, Pine Creek Orogen: Applications for uranium exploration: in 'Annual Geoscience Exploration Seminar (AGES) 2009. Record of abstracts'. Northern Territory Geological Survey, Record 2009-002.    **GLASS LM, Hollis JA, Carson CJ, Yaxley G and Armstrong R, 2010. Archaean and Palaeoproterozoic crustal evolution processes in the Pine Creek Orogen: U-Pb, Hf, O, Nd isotopic data and geochemistry: in 'Annual Geoscience Exploration Seminar (AGES) 2010, Record of abstracts'. Northern Territory Geological Survey, Record 2010-002.    **HOLLIS JA, Carson CJ and Glass LM, 2009a. Regionally extensive Neoarchaean basement in Arnhem Land: in 'Annual Geoscience Exploration Seminar (AGES) 2009. Record of Abstracts.' Northern Territory Geological Survey, Record 2009-002.    **HOLLIS JA, Scherstén A, Glass LM and Carson CJ, 2009b. Stratigraphic and tectonic evolution of the Nimbuwah Domain: a separate terrane to the rest of the Pine Creek Orogen?: in 'Annual Geoscience Exploration Seminar (AGES). Record of abstracts'. Northern Territory Geological Survey, Record 2009-002.    **HOLLIS JA, Carson CJ and Glass LM, 2009c. SHRIMP U-Pb zircon geochronological evidence for Neoarchean basement in western Arnhem Land, northern Australia. Precambrian Research 174(3-4), 364-380.    **NEEDHAM RS, Smart PG and Watchman AL, 1974. A reinterpretation of the geology of the Alligator Rivers uranium field, NT. Search 5(8), 397-399.    **WILLIAMS IS and Compston W, 1983. Ion microprobe U-Pb dating of zircons from granitoids recovered in core from drill holes P4/1D, P11/1, P12/11 and P14/1, Woolner, Northern Territory: in Manning ER, Richardson BR and Starkey LJ. Annual Report for EL 3478 "Woolner", Appendix 3. Mobil Energy Minerals Australia Inc. Northern Territory Department Geological Survey, Open File Company Report CR1983-0231.|16-MAY-23
68735|No Mans Sandstone Member|Name source|From No Mans Creek, which drains the western Carrara Range in southeastern MOUNT DRUMMOND.|16-MAY-23
68735|No Mans Sandstone Member|Unit history|Previously included in the Constance Sandstone on the first edition of MOUNT DRUMMOND by Smith and Roberts (1963), and on the Carrara Range region 1:100 000 sheet by Sweet (1984).|16-MAY-23
68735|No Mans Sandstone Member|Geomorphic expression|Forms a single low rocky ridge or narrow plateau up to 0.5 km wide.|16-MAY-23
68735|No Mans Sandstone Member|Type section locality|Three kilometres east-southeast of Mitchiebo Waterhole, continuing on from Top Lily Sandstone Member type section. Base is at latitude 18o39'25"S longitude 137o7'33"E (724230E 7935810N), and top is 450 m north, latitude 18o39'10"S longitude 137o7'33"E (724230E 7936260N).|16-MAY-23
68735|No Mans Sandstone Member|Extent|Forms a west to west-southwest-trending outcrop belt in southeastern and central Mount Drummond, from the headwaters of Maloney Creek in the east, to 7 km southwest of Mitchiebo Waterhole in the west.|16-MAY-23
68735|No Mans Sandstone Member|Thickness range|130 m in type section, and up to 200 m to the east. Thins to the north across Mitchiebo Fault, and only 50 m thick 17 km to the northwest in the Playford Anticline; absent in outcrops of Playford Sandstone further north and west.|16-MAY-23
68735|No Mans Sandstone Member|Lithology|Very coarse-grained to granule and pebbly, quartz-rich sandstone, and minor fine-grained sandstone with coarse to pebbly lags. Strongly trough cross bedded on medium to large scale throughout.|16-MAY-23
68735|No Mans Sandstone Member|Depositional environment|Braided fluvial and possibly shallow marine (intertidal).|16-MAY-23
68735|No Mans Sandstone Member|Relationships and boundaries|Lower contact, with the Top Lily Sandstone Member, is sharp and probably erosive at the type section. It is placed at the change from fine-grained pink lithic sandstone to coarse-grained and granular to pebbly quartz sandstone. The upper contact is also abrupt - sandstone beds become thinner upwards, and are overlain by mudstone of the Crow Formation. Both contacts are conformable. Parent units: Playford Sandstone, Wild Cow Subgroup, South Nicholson Group.|16-MAY-23
68735|No Mans Sandstone Member|Age reasons|A maximum age of 1591+/-10 Ma for the Playford Sandstone as a whole, based on reworked tuffaceous material from the underlying Lawn Hill Formation (Page et al 2000) in LAWN HILL, or 1595+/-6 Ma based on tuffs in the Lawn Hill Formation in the same area (Page and Sweet 1998). The interpreted age range of 1500-1400 Ma for the South Nicholson Group is based on its correlation with the Roper Group of the southern McArthur Basin (Dunn et al 1966; Plumb & Derrick 1975). Ages of 1492+/-4 and 1493+/-4 Ma for tuffaceous material from the Mainoru Formation in the Roper Group (Jackson et al 1999) provides the most reliable estimate for the age of the lower part of that Group, and hence for the Playford Sandstone and its members.|16-MAY-23
68735|No Mans Sandstone Member|Correlations|None known, but it is likely that sandstones low in the Renner Group (Hussey et al 2001) and the Roper Group (Jackson et al 1999) are in part correlative, given the overall correlation between these groups.|16-MAY-23
68735|No Mans Sandstone Member|Defn author|Sweet, I.P [aproved 11-APR-2005], after Rawlings, D. J. 2003|16-MAY-23
68735|No Mans Sandstone Member|Comments|The Playford Sandstone and its members, including the No Mans Sandstone Member, have been recognised and excluded from the Constance Sandstone as they lie unconformably beneath the Constance Sandstone as defined in the Lawn Hill 1:250 000 sheet area to the east. Note: All locations are based on the GDA94 geodetic datum. Standard series 1:250 000 sheet names are shown in upper case.|16-MAY-23
68735|No Mans Sandstone Member|References|**DUNN P.R., Plumb K.A. and Roberts H.G. 1966. A proposal for time-stratigraphic subdivision of the Australian Precambrian. Journal of the Geological Society of Australia, 13, 593-608.  **HUSSEY K.J., Beier P.R., Crispe A.J., Donnellan N. and Kruse P.D. 2001. Helen Springs, Northern Territory (Second Edition); 1:250 000 geological series, sheet SE53-10.   **JACKSON M.J., Sweet I.P., Page R.W. and Bradshaw B.E., 1999. The South Nicholson and Roper Groups: evidence for the early Proterozoic Roper Superbasin. In: Bradshaw B.E. and Scott D.L. (Eds.), Integrated basin analysis of the Isa Superbasin using seismic, well-log and geopotential data: an evaluation of the economic potential of the northern Lawn Hill Platform. Australian Geological Survey Organisation, Record 1999/19 (unpaginated).    **PAGE R.W., Jackson M.J. and Krassay A.A., 2000. Constraining sequence stratigraphy in north Australian basins: SHRIMP U-Pb zircon geochronology between Mt Isa and McArthur River. Australian Journal of Earth Sciences, 47, 3; 431-459.  **PAGE R.W. and Sweet I.P., 1998. Geochronology of basin phases in the western Mount Isa Inlier, and correlation with the McArthur Basin. Australian Journal of Earth Sciences, 45, 2; 219-232.  **PLUMB K.A. and Derrick G.M., 1975. Geology of the Proterozoic rocks of the Kimberley to Mount Isa Region. In Knight C.L. (Editor), Economic Geology of Australia and Papua New Guinea, 1. Metals. The Australasian Institute of Mining and Metallurgy, Monograph Series, 5, 217¿252.  **SMITH J.W. and Roberts H.G., 1963. Mount Drummond, N.T. (First Edition); 1:250,000 geological series, sheet SE53-12. Bureau of Mineral Resources, Geology and Geophysics, Map and Explanatory Notes.|16-MAY-23
14422|Nyanantu Formation|Name source|Nyanantu Creek, Mount Young 1:250 0000 scale map sheet area.|16-MAY-23
14422|Nyanantu Formation|Unit history|Previously mapped as 'Masterton Formation' in most areas by Plumb and Paine (1964) and Smith (1964). Outcrop at type section assigned to the lower Masterton Sandstone by Jackson and others (1987) and Pietsch and others (1991a,b).|16-MAY-23
14422|Nyanantu Formation|Geomorphic expression|Forms a prominent strike ridge at the type section. Low hills elsewhere.|16-MAY-23
14422|Nyanantu Formation|Type section locality|At Sawtooth Range in the northern part of the Bauhinia Downs 1:250 000 scale map sheet area. Base at latitude 16o05'50"S, longitude 135o51'20"E (AMG grid reference NC914198). Top at latitude 16o06'30"S, longitude 135o51'50"E (NC922189).|16-MAY-23
14422|Nyanantu Formation|Extent|Eastern half of the Mount Young and northern Bauhinia Downs 1:250 0000 map sheet areas.|16-MAY-23
14422|Nyanantu Formation|Thickness range|Estimated thickness of 450 m at the type section. Preserved thickness elsewhere is considerably thinner.|16-MAY-23
14422|Nyanantu Formation|Lithology|At type section: coarse-grained, cross-bedded, lithic sandstone with numerous pebble and cobble horizons. Thick beds of conglomerate near the base with distinctive porphyritic rhyolite clasts. Elsewhere: conglomeratic throughout with an abundance of rhyolitic clasts, except in northern parts of its range where these clasts are rare. Thin beds and veins of fine-grained rhyolite occur in the sequence at NC895655.|16-MAY-23
14422|Nyanantu Formation|Depositional environment|Probably deposited in a fluvial and alluvial fan environment.|16-MAY-23
14422|Nyanantu Formation|Relationships and boundaries|At the type section it overlies red sandstones assigned to ther Warramana Sandstone with a possibly disconformable or conformable relationship (contact not well exposed). The contact is picked at the incoming of conglomerate. On the Mount Young 1:250 0000 scale map sheet area it disconformably overlies the Warramana Sandstone and Gold Creek Volcanics, or lies above a non-outcropping unit inferred to be the Tanumbirini Rhyolite. At the type section it is overlain with probable disconformity by the Masterton Sandstone. The Masterton Sandstone is clearly distinguished by its much paler colour and clean (non-lithic) character. No assigned to any group.|16-MAY-23
14422|Nyanantu Formation|Age reasons|Statherian based on the 1713 +/- 6 Ma age of the underlying Tanumbirini Rhyolite (Haines and others, in press).|16-MAY-23
24436|Octy Formation|Name source|Mt Octy on Barrow 1:100 0000 sheet (AMG GR LR116673).|16-MAY-23
24436|Octy Formation|Unit history|Originally mapped as part of Central Mount Stuart beds (Smith & Milligan, 1964), but not included in Central Mount Stuart Formation type section of Offe (1978). Later placed in lower part of Donkey Creek beds (Walter, 1980). Outcrops south of Mt Octy miscorrelated with Grant Bluff Formation by Daily (1974). Mapped as unit PuCs3 of Central Mount Stuart beds by Shaw and Warren (1975) on Alcoota 1:250 000 sheet.|16-MAY-23
24436|Octy Formation|Geomorphic expression|Generally forms resistant capping on top of ranges.|16-MAY-23
24436|Octy Formation|Type section locality|22-25 km southeast of Neutral Junction homestead on Home of Bullion 1:100 000 sheet. Base at AMG GR MS160038 (latitude 21o38'48"S, 134o09'15"E); top at GR MS160003 (latitude 21o40'38"S, longitude 134o09'15"E). Approximate position of Donkey Creek beds type section (Walter, 1980).  Reference section: 29 km southwest of Stirling homestead on Barrow 1:100 000 sheet. Base of section at AMG GR LR682671 (latitude 22o00'13"S, longitude 133o43'23"E); top at LR685674 (latitude 21o59'40"S, longitude 133o43'36"E). Better outcrop than type section, but top not exposed.|16-MAY-23
24436|Octy Formation|Extent|SW quarter of Barrow Creek and central north of Alcoota 1:250 000 sheets.|16-MAY-23
24436|Octy Formation|Thickness range|68 m at type section; 88 m exposed at reference section (incomplete).|16-MAY-23
24436|Octy Formation|Lithology|White (often orange weathering) and brown, medium- to coarse-grained, cross-bedded feldspathic quartzarenite. Minor interbedded siltstone and purple silty sandstone. Basal conglomerate developed locally (mainly eastern areas). 14 m bioturbated purple and white mudstone at base at reference section. Trace fossils common.|16-MAY-23
24436|Octy Formation|Relationships and boundaries|Overlies Adnera Member of Central Mount Stuart Formation with probable disconformity. Base picked at sharp contact (with local basal conglomerate) between rarely fossiliferous red or white sandstone of Adnera Member and white trace fossil-bearing quartzarenite above. Overlain by Neutral Junction Formation with probabale disconformity. Top picked at irregular contact between coarse, cross-bedded sandstone (below) and poorly exposed greenish siltstone of the basal Neutral Junction Formation.|16-MAY-23
24436|Octy Formation|Structure and Metamorphism|Horizontal or gently dipping to southwest, except near faults.|16-MAY-23
24436|Octy Formation|Age reasons|Early Cambrian (probably Tommotian) based on trace fossils including Phycodes pedum.|16-MAY-23
24436|Octy Formation|Correlations|Part of upper Arumbera Sandstone (Arumbera III/IV) of Amadeus Basin. Probably correlates with part of upper Mount Baldwin Formation of southern Georgina Basin and part of upper Yuendumu Sandstone of Ngalia Basin.|16-MAY-23
24436|Octy Formation|Proposed publication|Barrow Creek 1:250 000 Geol. Series, Explan. Notes, NT Geological Survey|16-MAY-23
24436|Octy Formation|Category|2|16-MAY-23
24436|Octy Formation|Proposer|Haines P.W.|16-MAY-23
14496|Oenpelli Dolerite|Name source|Oenpelli Mission 133o04', 12o20'. Alligator River 1:250 000 Sheet area.|16-MAY-23
14496|Oenpelli Dolerite|Unit history|Walpole et al. (1958) misinterpreted some exposures as either Zamu Complex or Nungbalgarri Volcanic Member - remainder of exposures were unnamed dolerite.|16-MAY-23
14496|Oenpelli Dolerite|Type section locality|Graveside Gorge, 132o34', 13o18'. A ridge of differentiated dolerite 150 m high trending northeast along south side of gorge. Differentiates include porphyritic olivine dolerite, ophitic dolerite and ophitic gabbro with igneous lamination, granophyric dolerite and syenite.|16-MAY-23
14496|Oenpelli Dolerite|Extent|As arcuate ridges over 30,000 km2 in the Alligator River, Mount Evelyn, Milingimbi and Cobourg Peninsula 1:250 000 Sheet areas between 132o30' and 134o00', and 11o45' and 13o30'.|16-MAY-23
14496|Oenpelli Dolerite|Thickness range|Range <250 m. Arcuate ridges probably are exposed rims of roughly ellipsoidal basins which may be part of a large undulating sheet of dolerite, or mark individual lopoliths, the latter being supported by a general thickening of the dolerite towards the centres of the basins. There are also occasional narrow dykes of Oenpelli Dolerite (porphyritic olivine dolerite) >10 cm with sharp margins.|16-MAY-23
14496|Oenpelli Dolerite|Lithology|An approximately symmetrically differentiated dolerite intrusive sill. Central part is igneously laminated ophitic dolerite often displaying local ophitic gabbro, granophyric dolerite, granophyre and syenite differentiates as large lens-shaped bodies. Central part grades upwards and downwards with decrease in groundmass size to porphyritic olivine dolerite containing porphyroblasts of saussertized pale green plagioclase <5 cm. A chilled margin is rarely apparent at the outer margins of the porphyritic olivine dolerite phases. Gabbro pegmatite is rarely developed adjacent to the upper chilled margin (see accompanying card).|16-MAY-23
14496|Oenpelli Dolerite|Relationships and boundaries|Intrudes Nanambu and Nimbuwah migmatite Complexes. Intrudes all Lower Proterozoic sedimentary and metamorphic units. Forms basement highs to, and unconformably overlain by, Carpentarian Kombolgie Formation sandstone. Also intrudes Jim Jim Granite. Generally sharp contacts with country rock, which is usually hornfelsed. In central parts of Nimbuwah Complex however boundaries often gradational into country rock which was assimilated by the dolerite during intrusion.|16-MAY-23
14496|Oenpelli Dolerite|Age reasons|1720 m.y.  Total rock Rb-Sr isochron of 1718 +/- 65 m.y.  Page & Needham (in prep.).|16-MAY-23
14496|Oenpelli Dolerite|Proposed publication|Journal of the Geological Society of Australia|16-MAY-23
28161|Old Hamilton Downs Gneiss|Name source|Old Hamilton Downs homestead near the headwaters of Jay Creek in the eastern part of the MacDonnell Ranges 1:100 000 Sheet area.|16-MAY-23
28161|Old Hamilton Downs Gneiss|Type section locality|Along the track to the homestead; Alice Springs 1:100 000 Sheet area GR 5650-486858.|16-MAY-23
28161|Old Hamilton Downs Gneiss|Extent|Extends from north of Simpsons Gap in the Alice Springs 1:100 000 Sheet area westwards into MacDonnell Ranges 1:100 000 Sheet area.|16-MAY-23
28161|Old Hamilton Downs Gneiss|Lithology|Homogeneous granitic gneiss; more aptly described as muscovite gneiss in MacDonnell Ranges 1:100 000 Sheet area. Northeast margin in Alice Springs 1:100 000 Sheet area consists in part of migmatised biotite gneiss.|16-MAY-23
28161|Old Hamilton Downs Gneiss|Relationships and boundaries|Interfingers with the Charles River gneiss (new name) to the east, grades rapidly into unnamed gneiss to the northeast. Faulted to the northwest and south.|16-MAY-23
28161|Old Hamilton Downs Gneiss|Identifying features|Reason for proposed name: Distinctive homogeneous unit of granitic gneiss cropping out in an area surrounded by layered gneiss.|16-MAY-23
28161|Old Hamilton Downs Gneiss|Age reasons|The Old Hamilton Downs Gneiss is considered to be an anatectic granite which has formed during the thermal event which accompanied the Ormiston Phase of deformation at about 1080 m.y.|16-MAY-23
28161|Old Hamilton Downs Gneiss|Proposed publication|Geological report on 1:100 000 scale mapping of southeastern Arunta Block, Alice Springs 1:250 000 Sheet area, Northern Territory, by R D Shaw et al. BMR Microfiche report in prep.|16-MAY-23
28161|Old Hamilton Downs Gneiss|Defn Reference|80/20787|16-MAY-23
28161|Old Hamilton Downs Gneiss|Proposer|Offe L.A.|16-MAY-23
28161|Old Hamilton Downs Gneiss|Resdate|03-NOV-1975|16-MAY-23
28161|Old Hamilton Downs Gneiss|Reserved? Yes/No|yes|16-MAY-23
14563|Olympic Formation|Name source|The formation was named by Wells et al (1967) after Olympic Bore, ca 113 km southeast of Alice Springs; ALICE SPRINGS; ALICE SPRINGS, Amadeus Basin, Northern Territory. Wells et al (1967) called it the Olympic Member as the then proposed type section was approximately 25 km east of Olympic Bore.|16-MAY-23
14563|Olympic Formation|Unit history|The Olympic Formation was originally defined by Wells et al (1967) as a member of the Pertatataka Formation (of Prichard and Quinlan 1962). Preiss et al (1978) upgraded the unit to formation status due to the redefinition of the Pertatataka Formation (and its constituent members) and the definition and recognition of the overlying Pioneer Sandstone which might be a possible equivalent of the upper Olympic Formation.|16-MAY-23
14563|Olympic Formation|Geomorphic expression|Exposures of diamictite and sandstone often form rounded hills and ridges, whereas the siltstone facies of the Olympic Formation are recessive and are often only exposed in creeks and incised valleys.|16-MAY-23
14563|Olympic Formation|Type section locality|Type section of  Olympic Member of  Wells et al. (1967) (ASR4, Plate 10) is 5 miles SE of Ringwood homestead (Note: Plate 10 says 4 miles SE) on the Alice Springs 1:250 000 sheet.|16-MAY-23
14563|Olympic Formation|Type section locality|The type area for the Olympic Formation is the centre of the Hi Jinx Syncline, HALE RIVER, from GDA94 53J 508526mE 7338785mN (base) on the eastern limb to GDA94 53J 500411mE 7361081 mN where diamictite units make up a series of ridges and siltstone units are exposed in creeks, incised valleys and at the base of hill slopes.|16-MAY-23
14563|Olympic Formation|Description at type locality|The Olympic Formation is comprised primarily of glacially-derived units including diamictite, sandstone and siltstone and as a consequence the unit is generally poorly or sporadically exposed. The most distinctive and best-exposed units are those composed of diamictite. The diamictite units form the ridge in the centre of the syncline as well as small, isolated rises to the south of the central ridge. These units are variably ferruginised, granule to pebble, matrix-supported diamictite. Occasional exposures of laminated and medium bedded, red siltstone occur within creek banks and incised valleys. These occur between the exposed diamictite and are possibly interbedded with the diamictite. Some poor exposures of siltstone also occur in mostly soil covered intervals between diamictite unit exposures. The siltstone becomes increasingly sandier towards the centre of the syncline.|16-MAY-23
14563|Olympic Formation|Extent|The Olympic Formation is poorly outcropping with the best exposures recorded at the type area in the centre of the Hi Jinx Syncline in northwestern HALE RIVER (GDA94 53J 50246mE 7339276mN). Other recorded exposures occur in southeastern ALICE SPRINGS in the vicinity of Olympic Bore (GDA94 53K 496068mE 7349433mN) and near Mt Capitor Bore (GDA94 53J 469702mE 7341159mN) and Larrier Bore (GDA94 53J 478218mE, 7323453mN) in RODINGA.|16-MAY-23
14563|Olympic Formation|Thickness range|Thickness of the Olympic Formation can vary significantly within one exposure. The thickness of the type area is about 1100 m. Due to the limited continuous exposures of the Olympic Formation it is difficult to ascertain a true thickness. Thickness varies from approximately 60m near Mt Capitor Bore to 20 m at Larrier Bore. Wells et al (1967) reported a thickness of about 200 m near Halfway Dam and ridges of up to 60 m where resistant ridges of the Olympic Formation have formed.|16-MAY-23
14563|Olympic Formation|Lithology|As is typical for most glacial deposits the Olympic Formation has a number of facies which include lenticular units of diamictite, sandstone, siltstone, conglomerate, shale, boulder clay and dolomite in varying proportions. The Olympic Formation shows rapid lateral variation in thickness and lithology (Wells et al 1967). Clasts within the diamictite include carbonate rocks of the Bitter Springs Group, siltstone and rock fragments that include basement-derived quartzite, gneiss, granite and vein quartz. The siltstone clasts are likely to have been derived from the underlying Aralka Formation as well as from siltstone beds within the lower part of the Olympic Formation. It is likely that the basement-derived rock fragments are at least partially derived from the underlying glacigene Areyonga Formation.|16-MAY-23
14563|Olympic Formation|Depositional environment|The presence of diamictite units and striated, faceted and polished erratics confirms the presence of glacial ice in the region. The absence of glaciated pavements and compaction of underlying strata infers that the glaciation was not that of a large continental ice sheet. This is confirmed by the thickness of the diamictite units which is limited to a few metres, suggesting that the large, active glaciers were not proximal to the deposits (Ashley et al 1985, Field 1991a). The other lithologies in the Olympic Formation suggests depositional environments that were partly terrestrial, partly marine and lacustrine (Field 1991a). This deposition is likely to have occurred on the edge of glaciers or in terrains adjacent to glacial lobes.|16-MAY-23
14563|Olympic Formation|Fossils|None known.|16-MAY-23
14563|Olympic Formation|Diastems or hiatuses|Nil.|16-MAY-23
14563|Olympic Formation|Relationships and boundaries|The Olympic Formation is observed in unconformable contact with the underlying Gillen Formation, Johnnys Creek Formation, and the Limbla Formation within the northeast of the basin. The Olympic Formation cuts into the underlying strata at varying depths across the northeast of the basin; the underlying unit varies from exposure to exposure. As most of the Olympic Formation is poorly exposed, the upper contact is only seen where the Olympic Formation sediments form a ridge or hill. Siltstone units of the Pertatataka Formation and sandstone units of the Waldo Pedlar Member of the Pertatataka Formation typically cap exposures of the Olympic Formation.|16-MAY-23
14563|Olympic Formation|Identifying features|Diamictite units of the Olympic Formation have a reduced basement clast content compared to diamictite units of the Areyonga Formation. It is possible that the proportion of basement clasts could be diagnostic of the Olympic Formation however stratigraphic position is a more accurate indicator.|16-MAY-23
14563|Olympic Formation|Identifying features|The Olympic Member of Wells et al. (1967) is here upgraded to formation status because of the redefinition of the Pertatataka Formation and the recognition of the Pioneer Sandstone, a probable correlative of the Olympic Formation. This allows the lower boundary of the Pertatataka Formation to be placed at the same stratigraphic position throughout the northern Amadeus Basin.|16-MAY-23
14563|Olympic Formation|Structure and Metamorphism|The Olympic Formation has been folded and faulted during both the 580¿530 Ma Petermann and 450¿300 Ma Alice Springs orogenies (Edgoose 2013 and references therein). Due to the poor exposure and unconsolidated sediments of the Olympic Formation it is difficult to characterise the effect these events had on the formation.|16-MAY-23
14563|Olympic Formation|Age reasons|The age of the Olympic Formation is constrained by correlations with the Chambers Bluff Tillite in the Officer Basin. The tillite gave a 651 ± 87 Ma Rb-Sr age (Freeman et al 1991). This age correlates with other glacial units known to have formed during the Elatina glaciation (Freeman et al 1991).Recent U-Pb isotopic studies of detrital zircons from a sandstone bed within the Olympic Formation yielded a maximum depositional age of 690 +/- 14 Ma (Kositcin et al 2015). This is only slightly older than the current constraint of 640 ¿ 580Ma for the Olympic Formation.|16-MAY-23
14563|Olympic Formation|Correlations|Olympic Formation has been correlated with the diamictite member of the Mount Doreen Formation in the Ngalia Basin and the Elatina Formation of the Adelaide Rift Complex (Preiss et al 1978). Cap carbonates or cap dolostones of the Olympic Formation have been correlated with the Nuccaleena Formation of the Adelaide Rift Complex (Walter et al 1995). The unit is also correlated with the Oorabra and Black Stump arkoses, and the Boko Formation in the Georgina Basin (Walter 1980) as well as the Chambers Bluff Tillite in the Officer Basin (Freeman et al 1991). The Pioneer Sandstone is interpreted to be a lateral equivalent of the Olympic Formation (Field 1991b); the Pioneer Sandstone is also restricted to the northeast of the basin.|16-MAY-23
14563|Olympic Formation|Alteration and Mineralisation|Petroleum: The Olympic Formation is included in the 2nd Petroleum system of Marshall et al (2007) but is not thought to be a significant component (Munson 2014).|16-MAY-23
14563|Olympic Formation|Geophysical Expression|The Olympic Formation is detected in seismic lines however the unit is often too thin or disrupted to follow across the basin.|16-MAY-23
14563|Olympic Formation|Geochemistry|Not known.|16-MAY-23
14563|Olympic Formation|Defn author|VJ Normington, N Donnellan 29-SEP-2015.|16-MAY-23
14563|Olympic Formation|Defn author|Preiss, W. 1977. Original definition approved by A.T. Wells on 1-OCT-1977.|16-MAY-23
14563|Olympic Formation|Proposed publication|BMR Journal|16-MAY-23
14563|Olympic Formation|Comments|Although a definition card exists for this formation no type locality has previously been assigned.|16-MAY-23
14563|Olympic Formation|References|Ashley GM, Shaw J and Smith ND, 1985. Glacial sedimentary environments. SEPM Short Course No. 16. Oklahoma, USA, Society of Palaeotologists and Mineralogists. **Edgoose C, 2013. Amadeus Basin: in Ahmad M and Munson TJ (editors) 'Geology and mineral resources of the Northern Territory; Special Publication 5', Northern Territory Government. **Field BD, 1991a. Measured sections of the Late Proterozoic Olympic Formation, Pioneer Sandstone and Gaylad Sandstone, Amadeus Basin, central Australia BMR Record 1991/69. BMR Geology and Geophysics. ** Field BD, 1991b. Paralic and periglacial facies and contemporaneous deformation of the Late Proterozoic Olympic Formation, Pioneer Sandstone and Gaylad Sandstone, Amadeus Basin, Central Australia: in Korsch RJ and Kennard J (editors) 'Geological and geophysical studies in the Amadeus Basin, central Australia. ' Bulletin 236. Australia, Bureau of Mineral Resources. **Freeman M, Oaks R and Shaw R, 1991. Stratigraphy of the Late Proterozoic Gaylad Sandstone, northeastern Amadeus Basin, and recognition of an underlying regional unconformity: in Korsch RJ and Kennard J (editors) 'Geological and geophysical studies in the Amadeus Basin, central Australia. ' Bulletin 236. Australia, Bureau of Mineral Resources. **Kositcin N, Normington V and Edgoose C, 2015. Summary of results. Joint NTGS-GA geochronology project: Amadeus Basin, July 2013-June 2014. NTGS Record 2015-001, Northern Territory Geological Survey. **Marshall TR, Dyson IA and Liu Keyu, 2007. Petroleum systems in the Amadeus Basin, central Australia: Were they oil prone?: in Munson TJ and Ambrose GJ (editors) 'Proceedings of the Central Australian Basins Symposium, Alice Springs, 16 ¿ 18th August, 2005'. Alice Springs, Northern Territory Geological Survey, Special Publication 2, 136-146. **Munson TJ, 2014. Petroleum geology and potential of the onshore Northern Territory, 2014, Northern Territory Geological Survey, Report 22. **Normington VJ and Donnellan N, in prep. Characterisation of the Neoproterozoic stratigraphy of the northeast Amadeus Basin, Northern Territory. Record 2015-##, Northern Territory Geological Survey. **Preiss WV, Walter MR, Coats RP and Wells AT, 1978. Lithological correlations of Adelaidean glaciogenic rocks in parts of the Amadeus, Ngalia, and Georgina basins. BMR Journal of Australian Geology and Geophysics 3, 43-53. **Prichard CE and Quinlan T, 1962. The geology of the southern half of the Hermannsburg 1:250 000 sheet. BMR Report No. 61. Bureau of Mineral Resources Geology and Geophysics.  **Walter MR, 1980. Adelaidean and early Cambrian stratigraphy of the southwestern Georgina Basin, Australia: correlation chart and explanatory notes. , Bureau of Mineral Resources, Australia, Report 214: BMR Microform MF92. **Walter MR, Veevers JJ, Calver CR and Grey K, 1995. Neoproterozoic stratigraphy of the Centralian Superbasin, Australia. Precambrian Research 73, 173-195. **Wells AT, Ranford LC, Stewart AJ, Cook PJ and Shaw R, 1967. Geology of the north-eastern part of the Amadeus Basin, Northern Territory BMR Report 113, Australia.|16-MAY-23
14563|Olympic Formation|Status|1|16-MAY-23
24443|Oolloo Dolostone|Name source|'Oolloo' property, south-central Tipperary 1:1000 000.|16-MAY-23
24443|Oolloo Dolostone|Unit history|Oolloo Limestone (Randal, 1962; Malone, 1962).|16-MAY-23
24443|Oolloo Dolostone|Constituents|The Oolloo Dolostone has been subdivided into two new members in 2014; the Briggs Member comprising the lower third of the formation and the King Member comprising the upper third. This subdivision has been recognised and mapped across the full extent of the formation in both outcrops and in boreholes.|16-MAY-23
24443|Oolloo Dolostone|Geomorphic expression|Flat to undulating plains with isolated residuals.|16-MAY-23
24443|Oolloo Dolostone|Type section locality|51.5-243.9 m in cored drillhole NTGS 86/1, northeastern Jinduckin 1:100 0000, AMG587327 (latitude 14o09'50"S, longitude 131o23'50"E). Core stored at NTGS Core Library, Darwin.|16-MAY-23
24443|Oolloo Dolostone|Extent|Outcrop in Pine Creek, Fergusson River and Katherine 1:250 000.|16-MAY-23
24443|Oolloo Dolostone|Thickness range|Maximum 192.4 m in type section; "200m" (Jolly, 1984), but probably 190-195 m in percussion drillhole DB10 (south-central Tipperary 1:100 000). Thickness in type section is treated as definitive.|16-MAY-23
24443|Oolloo Dolostone|Lithology|Pink-grey dolostone, ooid dolograinstone, stromatolitic doloboundstone and cryptalgal dololaminate, minor dolomitic sandstones toward base. Occasion flat pebble breccias and other indications of erosive surfaces representing minor hiatuses.|16-MAY-23
24443|Oolloo Dolostone|Relationships and boundaries|Conformable gradational contact with Jinduckin Formation below; in places unconformably overlain by Cretaceous sandstones (Petrel Formation, Bathurst Island Formation). In type section, lower boundary of unit is placed at top of highest finely laminated dolomitic sandstone-siltstone interbeds in the sequence; upper boundary is unconformity with Cretaceous sandstones.|16-MAY-23
24443|Oolloo Dolostone|Structure and Metamorphism|Horizontal to very gently dipping.|16-MAY-23
24443|Oolloo Dolostone|Age reasons|An Early Ordovician age based on conodonts was ascribed to the formation in its original definition. The strata in which the fossils were found are now considered to belong to the Florina Formation, a newly recognised unit unconformably overlying the Oolloo Dolostone. The Oolloo Dolostone is unfossiliferous but its age is broadly constrained by the securely dated early middle Cambrian Tindall Limestone below and the early Ordovician Florina Formation above. A middle Cambrian age is considered most likely from the presence of generally conformable contacts between units of the Daly River Group and from broad lithological correlations with the Georgina Basin middle Cambrian succession.|16-MAY-23
24443|Oolloo Dolostone|Age reasons|Early Ordovician. Conodonts place the lowermost Oolloo Dolostone at Claravale (southwestern Fergusson River 1:100 000), within the early Arenig Drepanodus? Gracilis - Scolopodus sexplicatus Assemblage Zone of Druce & Jones (1971; Jones, 1971; Webby and others, 1981).|16-MAY-23
24443|Oolloo Dolostone|Correlations|Pander Greensand (Bonaparte Basin) and Datson Member of Ninmaroo Formation (Georgina Basin) - Jones (1971).|16-MAY-23
24443|Oolloo Dolostone|Proposed publication|Tipperary 1:100 000 explanatory notes. NTGS|16-MAY-23
24443|Oolloo Dolostone|Proposer|Kruse P.D. in 1988; originally Randal (1962), Malone (1962)|16-MAY-23
24443|Oolloo Dolostone|Status|1|16-MAY-23
14610|Oorabra Arkose|Type section locality|The type section is that selected by Smith (1964), for the Oorabra Arkose Member,  "half a mile" NNE of Grant Bluff, Huckitta 1:250 000 Sheet area, where the formation is 25 m thick without the top being exposed (p22. See also p25).|16-MAY-23
14610|Oorabra Arkose|Identifying features|The Oorabra Arkose as named by Joklik (1955) and formalised by Smith (1964) as a member of the Elyuah Formation is now considered to lie disconformably and locally with slight angular unconformity beneath the former upper member of the Elyuah Formation (Walter, 1979). The angular unconformity has been recognised by photo-interpretation of the eastern Mopunga Range, in the newly named Mopunga Trough. The base of the redefined Elyuah Formation is marked by the base of sandstone and pebbly arkose.  The Oorabra Arkose is here raised to the status of a formation. It is discontinuous between depositional troughs but for convenience the same name is applied in each trough in the Huckitta area. The name is not used for the arkose at Poomingie Waterhole on the Alcoota 1:250 000 Sheet area because of some uncertainty about the correlation of that unit. The type section is that selected by Smith (1964), "half a mile" NNE of Grant Bluff, Huckitta 1:250 000 Sheet area, where the formation is 25 m thick without the top being exposed.|16-MAY-23
14610|Oorabra Arkose|References|Smith, K.G. 1964. Progress report on the geology of the Huckitta 1:250 000 sheet, Northern Territory. BMR Report 67.|16-MAY-23
27297|Ooralingie Granite|Name source|Ooralingie Bore (AMG GR MR128826) on the Home of Bullion 1:100 000 sheet (5754)|16-MAY-23
27297|Ooralingie Granite|Unit history|Previously included in the 'Barrow Creek Granite' (Smith and Milligan, 1964).|16-MAY-23
27297|Ooralingie Granite|Geomorphic expression|Low irregular hills and large tors; medium airphoto tones, slightly darker than those of the Bean Tree Granite.|16-MAY-23
27297|Ooralingie Granite|Type section locality|At the Barrow Creek Racecourse on the Barrow 1:100 000 sheet at AMG GR LS862204 (latitude 21o30'58"S, longitude 133o53'55"E).|16-MAY-23
27297|Ooralingie Granite|Extent|Southeastern corner of Crawford (5655), northeastern corner of Barrow (5654) and northwest corner of Home of Bullion 1:100 000 sheets.|16-MAY-23
27297|Ooralingie Granite|Lithology|Granite-adamellite: medium to very coarse, foliated, porphyritic, with biotite, partly sericitised plagioclase, quartz (with undulose extinction) and alkali feldspar, minor muscovite, sericite, epidote, apatite and opaque minerals, and traces of zircon and chlorite +/- sphene.|16-MAY-23
27297|Ooralingie Granite|Relationships and boundaries|Included in the Barrow Creek Granite Complex. Intruded by the Bean Tree Granite (e.g. at AMG GR LS893080) and unnamed pegmatite (Pgbc). Intrudes the Bullion Schist.|16-MAY-23
27297|Ooralingie Granite|Structure and Metamorphism|Faulted in places. Foliated.|16-MAY-23
27297|Ooralingie Granite|Age reasons|Probably Early to Middle Proterozoic. Older than the Bean Tree Granite, which intrudes it and which is considered to be Middle Proterozoic. Younger than the Bullion Schist which is probably Early Proterozoic.|16-MAY-23
27297|Ooralingie Granite|Proposed publication|Barrow Creek 1:250 000 Geol. Series, Explan. Notes, NT Geological Survey|16-MAY-23
27297|Ooralingie Granite|Category|2|16-MAY-23
27297|Ooralingie Granite|Proposer|Bagas L.|16-MAY-23
29772|Ormiston Pound Granite|Name source|Ormiston Pound.|16-MAY-23
29772|Ormiston Pound Granite|Unit history|Originally assigned by Marjoribanks and Black (1974) to anatectic granites of the so-called Ormiston Event, since renamed to Teapot Tectonothermal Event, and so presumed to have an age of 1000-1100 Ma, but now considered to be part of the Central part of the Chewings Orogeny at about 1600 Ma.|16-MAY-23
29772|Ormiston Pound Granite|Geomorphic expression|Rubble-covered low rise, boulders and tors, locally.|16-MAY-23
29772|Ormiston Pound Granite|Type section locality|The Ormiston Pound, just east of the main gorge. GR 312200 7485200.|16-MAY-23
29772|Ormiston Pound Granite|Extent|Occupies the central part of Ormiston Pound.|16-MAY-23
29772|Ormiston Pound Granite|Lithology|Equigranular, medium to fine-grained homogenous, pale pink, biotite-bearing alkaline leucogranite, also minor pegmatite.|16-MAY-23
29772|Ormiston Pound Granite|Relationships and boundaries|Intruded as, a small body and a series of north-south and minor east-west dykes, into a highly foliated migmatitic gneiss tentatively assigned to the Glen Helen Metamorphics. Also intrudes the Lovely Hills Schists; unconformably overlain by the Heavitree Quartzite.|16-MAY-23
29772|Ormiston Pound Granite|Structure and Metamorphism|Some of the granite and granite dykes are undeformed while others are weakly deformed by the main regional D2 two-mica foliation-forming event of, the redefined Chewings Orogeny (Collins & Shaw in press, compare with Teyssier et al., 1988, Shaw et al., 1984). So, the U-Pb zircon age of 1603 +/- 10 Ma (Collins et al., 1994) for the granites gives the age of the Chewings Orogeny. Majoribanks and Black (1974) obtained a Rb-Sr whole-rock age of 1586 +/- 70 Ma <a for amphibolite facies gneiss from near Ormiston Pound, an age which is considered to approximate the D2 deformation of Teyssier (1988). Thje granite has been recrystallised presumably under amphibolite facies conditions, during the Teapot Tectonothermal Event at 1000-1100 Ma, reflected by Rb-Sr and 40Ar/39 Ar ages (Majoribanks & Black 1974; Shaw et al. 1992b).|16-MAY-23
29772|Ormiston Pound Granite|Age reasons|U-Pb zircon age of 1603 +/- 10 Ma (Collins et al., 1994) is the age of intrusion. Minor resetting has occurred during the Teapot Tectonothermal Event at about 1110 Ma.|16-MAY-23
29772|Ormiston Pound Granite|Correlations|Bluff Gneiss dated at about 1605 Ma (Zhao & Bennett 1993). Also correlates with units within the Ellery Granite Complex.|16-MAY-23
29772|Ormiston Pound Granite|Defn author|R.D. Shaw & W. Collins, 1995.|16-MAY-23
29772|Ormiston Pound Granite|Comments|This 'definition' is missing the details of references mentioned throughout, and shows no signs on the card of having been approved.|16-MAY-23
77885|Pandanus Formation|Name source|Unit name derived from Pandanus Creek, Northern Territory. Creek rises at a point approximately 45 km south by southwest of Wollogorang Station, Northern Territory, and approximately 13 km west of the Queensland-Northern Territory border (Roberts, unpublished manuscript).|
77885|Pandanus Formation|Unit history|Unit originally defined as the “Pandanus Siltstone Member” of the Constance Sandstone by Roberts (unpublished manuscript). Unit mapped as the “Pandanus Siltstone Member” on the First Edition CALVERT HILLS 1:250 000 mapsheet (Roberts et al, 1963) and MOUNT DRUMMOND 1:250 000 (Smith and Roberts, 1963a, b) mapsheet. Unit reclassified as the “Pandanus Formation” by Sweet (2017), most likely due to the interpretation of a minor unconformity at the top of the Pandanus Formation.|
77885|Pandanus Formation|Geomorphic expression|Mostly forms poorly-exposed scree-covered outcrops in low scarps (Sweet and Slater, 1975; Sweet, 2017).|
77885|Pandanus Formation|Type section locality|Reference area nominated at (GDA94) 17°56’S, 137°52’E (53K 803690mE 8014850mN), approximately 5 km northwest of the confluence of Pandanus Creek and the Nicholson River (Roberts, unpublished manuscript). This is retained as a type area.|
77885|Pandanus Formation|Extent|The Pandanus Formation, previously the Pandanus Siltstone Member, has been mapped across the CALVERT HILLS and MOUNT DRUMMOND 1:250 000 mapsheets in the Northern Territory, and the western LAWN HILL 1:250 000 mapsheet in Queensland (Sweet and Slater, 1975; Sweet, 2017).|
77885|Pandanus Formation|Thickness range|The unit is at least 120 m thick in the type section (Sweet and Slater, 1975), thinning to approximately 50 m thick to the west. The formation reaches approximately 130 m thick in the HEDLEYS CREEK 1:100 000 mapsheet, thinning to approximately 60 m thick elsewhere on this mapsheet.).|
77885|Pandanus Formation|Lithology|The unit consists of fissile and flaggy, green, purple and red-brown, coarse-grained micaceous siltstone with shaly partings and thin interbeds of very fine-grained sandstone. A prominent blocky sandstone bed is present in about the middle of the member across much of the SEIGAL 1:100 000 mapsheet. The sandstone forms a slight bench in the type section (Sweet and Slater, 1975).|
77885|Pandanus Formation|Depositional environment|Unit is interpreted as depositing in a storm-dominated shelf environment (Sweet, 2017).|
77885|Pandanus Formation|Relationships and boundaries|The lower boundary of the Pandanus Formation with the underlying Hedleys Formation is thought to be conformable (Sweet and Slater, 1975). The upper boundary of the Pandanus Formation with the overlying Burangoo Sandstone is sharp, erosive, and is interpreted as unconformable (Sweet, 2017).|
77885|Pandanus Formation|Identifying features|The Pandanus Formation is recessive, and forms scree-covered slopes between outcrops of the more resistant Hedleys Formation below and the Burangoo Sandstone above (Sweet, 2017). A prominent blocky sandstone bed is present in about the middle of the member across much of the SEIGAL 1:100 000 mapsheet.|
77885|Pandanus Formation|Age reasons|Maximum depositional ages derived from U-Pb SHRIMP dating of detrital zircons: Constance Sandstone (stratigraphically overlies Pandanus Formation): GA sample 2678595 - 1591 ± 18 Ma (Anderson et al, 2019). Doomadgee Formation (stratigraphically underlies Pandanus Formation): GA sample 2678601 - 1612 ± 11 Ma (Anderson et al, 2019). Therefore, the potential depositional age range for the Pandanus Formation can be considered to extend from ca. 1612 ± 11 Ma to 1591 ± 18 Ma.|
77885|Pandanus Formation|Correlations|No precise correlations at the formation level are known. Given the potential depositional age range of ca. ca. 1612 ± 11 Ma to 1591 ± 18 Ma, the Hedleys Formation may be correlative with components of the upper Glyde package to the Favenc package of the McArthur Basin (Rawlings, 1999).|
77885|Pandanus Formation|Geophysical Expression|Weak to moderate magnetic response, likely due to the sandstone formations in the South Nicholson Group possessing “subtle magnetic layering” (Rawlings et al, 2008).|
77885|Pandanus Formation|Defn author|Elliot Foley, Jack Simmons, Ben Williams, Charles Verdel (Northern Territory Geological Survey), Chris Carson (Geoscience Australia) 31-MAY-2023.|
77885|Pandanus Formation|Comments|Standard series 1: 100 000 and 1: 250 000 mapsheet names are shown in uppercase.|
77885|Pandanus Formation|References|Anderson JR, Lewis CJ, Jarrett AJM, Carr LK, Henson P, Carson CJ, Southby C and Munson TJ, 2019. New SHRIMP U–Pb zircon ages from the South Nicholson Basin, Mount Isa Province and Georgina Basin, Northern Territory and Queensland. Geoscience Australia, Record 2019/10. 
 **Carson, C. J., Kositcin, N., Anderson, J. R., and Henson, P. A. in prep. A revised Proterozoic tectono-stratigraphy of the South Nicholson region, Northern Territory, Australia - insights from SHRIMP U-Pb detrital zircon geochronology. Australian Journal of Earth Sciences. 
 **Rawlings DJ, 1999. Stratigraphic resolution of a multiphase intracratonic basin system: the McArthur Basin, northern Australia. Australian Journal of Earth Sciences 46(5), 703-723.  **Rawlings DJ, Sweet IP and Kruse PD, 2008. Mount Drummond, NT (Second Edition). 1:250 000 Geological Map Series Explanatory Notes, Sheet SE 53-12. Northern Territory Geological Survey, Darwin, Northern Territory.  **Roberts HG, Rhodes JM and Yates KR, 1963. Calvert Hills, Northern Territory (First Edition). 1:250 000 geological map series explanatory notes, SE 53‑8. Bureau of Mineral Resources, Canberra.  **Smith JW and Roberts HG, 1963a. Mount Drummond, NT (First Edition). 1:250 000 Geological Map Series Explanatory Notes, Sheet 53-12. Bureau of Mineral Resources, Canberra.  **Smith JW and Roberts HG, 1963b. Mount Drummond, NT (First Edition). 1:250 000 Geological Map Series, Sheet SE 53-12. Bureau of Mineral Resources, Canberra.  **Sweet IP, 2017. The geology of the South Nicholson Group, northwest Queensland. Queensland Geological Record 2017/07.  **Sweet IP and Slater PJ, 1975. Precambrian Geology of the Westmoreland Region, northern Australia. Bureau of Mineral Resources Record 1975/88. Bureau of Mineral Resources, Canberra.|
28201|Pandanus Siltstone Member|Name source|Pandanus Creek, NT, which rises at a point 28 miles S by SW of Wollogorang Station, NT and 8 miles west of the Qld-NT border. It folws approximately due S for 25 miles to join the Nicholson River 6 miles W of the State border.|16-MAY-23
28201|Pandanus Siltstone Member|Unit history|The member was defined by Roberts (unpubl. MS), and was mapped in the Calvert Hills and Mount Drummond 1:250 000 Sheet areas by Roberts et al. (1963) and Smith & Roberts (1963) respectively. It was not distinguished in the Westmoreland 1:250 000 Sheet area by Carter (1959), although it forms a prominent valley between cuestas of sandstone in the Hedleys Creek Sheet area.|16-MAY-23
28201|Pandanus Siltstone Member|Type section locality|Roberts nominated a reference area around lat. 17degrees 56'S, long. 137degrees 52'E, about 5 km northwest of the confluence of Pandanus Creek and the Nicholson River. This is retained as a type section.|16-MAY-23
28201|Pandanus Siltstone Member|General description|The Pandanus Siltstone Member consists of fissile and flaggy, green, purple and reddish brown, coarse micaceous siltstone (e.g. 74760156) with shaly partings and thin interbeds of very fine sandstone. A prominent blocky sandstone bed is present in about the middle of the member in much of the Seigal Sheet area. Most exposures are in scarps capped by Psa 2 [part of the Constance Sandstone] , and consist of weathered ferruginous rubble. The blocky sandstone bed is well exposed between 1 and 7 km east of Wallis Creek (grid ref. 685110). One kilometre east of the creek it comprises 2 m of cross-bedded, reddish, fine to medium quartz sandstone overlain by 2 m of blocky white fine-grained orthoquartzite. Six kilometres to the northeast the unit is about 5 m thick and consists of flaggy fine-grained sandstone showing low-angle cross-bedding, primary current lineations, mud clasts, and sandstone concretions (Table 23, 74760153, 0154 [probably AGD66]).The sandstone forms a slight bench in a scarp in the type section, but was not observed farther east. In the southwestern part of the Hedleys Creek Sheet area, the member is poorly exposed, as it is partly masked by Lower Cretaceous rocks. East and southeast of Wire Creek the upper part of the member crops out in low scarps, and the lower part is poorly exposed in valleys. Fine-grained labile sandstone beds and lenses are common here, interbedded with micaceous silt stone.|16-MAY-23
28201|Pandanus Siltstone Member|Thickness range|The Pandanus Siltstone Member increases in thickness from about 50 m in the west to at least 120 in at the type section. It is estimated to be 130 m thick at Wire Creek, but it thins southwards, and is only 60 m thick near the Nicholson River 4 km southeast of Connolly Waterhole. Farther to the southeast the Pandanus Siltstone Member appears to have lensed out. The member is definitely absent in the Bowthorn Sheet area to the south, where the entire Constance Sandstone is well exposed.|16-MAY-23
28201|Pandanus Siltstone Member|Relationships and boundaries|Both the lower and upper contacts of the Pandanus Siltstone Member, with Psa 1 and Psa 2 [parts of the Constance Sandstone] respectively, are conformable. Roberts (unpubl., MS) considered that the member formed the base of the Constance Sandstone in parts of the Calvert Hills Sheet area, but our mapping has shown that there is always at least a thin veneer (as little as 1 m) of Psa 1 below.|16-MAY-23
28201|Pandanus Siltstone Member|Defn author|Sweet, I.P., Slater, P.J. 1975. after Roberts, H.G. in Techfile E/53-8 [Calvert Hills] ~1962.|16-MAY-23
28201|Pandanus Siltstone Member|References|ROBERTS, H.G., RHODES, J.M., & YATES, K,R., 1963 - Calvert Hills, Northern Territory - 1:250 000 Geological Series. Bur. Miner. Resour. Aust. explan. Notes SE/53-8.  **SMITH, J.W., & ROBERTS, H.G., 1963 - Mount Drummond, Northern Territory - 1:250 000 Geological Series. Ibid SE/53-12.  **Sweet, I.P., Slater, P.J. 1975. Precambrian geology of the Westmoreland region, northern Australia. Part I: regional setting and cover rocks. BMR Record 1975/88|16-MAY-23
41848|Papunya Igneous Complex|Name source|Papunya community 23o 13' 00" S, 131o 54' 00" E, MOUNT LIEBIG.|16-MAY-23
41848|Papunya Igneous Complex|Unit history| Previously included within undifferentiated gneiss, schist, amphibolite, quartzite, granite, dolerite and pegmatite and undifferentiated granite of Ranford (1969). Includes informally named Papunya gabbro, South Papunya gabbro, Papunya ultramafic and West Papunya gabbro of Hoatson and Stewart (2001) and Hoatson and Clauoe-Long (2002).|16-MAY-23
41848|Papunya Igneous Complex|Geomorphic expression|Low to prominent bouldery hills, locally steep-sided.|16-MAY-23
41848|Papunya Igneous Complex|Type section locality|1 km north of Beantree Creek at location 23o18'11.48"S, 131o48'43.44"E (WGS 84), MOUNT LIEBIG.|16-MAY-23
41848|Papunya Igneous Complex|Description at type locality|Outcrop of metagabbro, biotite tonalite and leucogranite. The gabbro has largely recrystallised to mafic amphibolite and less common granulite, and contains a number of hybrid variants including biotite gabbro, quartz gabbro and biotite tonalite, with larger bodies of biotite leucogranite (Hoatson and Stewart 2001).|16-MAY-23
41848|Papunya Igneous Complex|Extent|Numerous bodies ranging from outcrop-scale dykes and sills to plutons scattered through hills up to 30 km east and southeast of Papunya, north of Belt Range, MOUNT LIEBIG.|16-MAY-23
41848|Papunya Igneous Complex|Lithology|Mafic granulite and amphibolite, gabbro and gabbronorite, quartz gabbro; less common plagioclase pyroxenite, pyroxenite, biotite tonalite and biotite leucogranite.|16-MAY-23
41848|Papunya Igneous Complex|Relationships and boundaries|Intrudes metasediments and orthogneiss of the Yaya Metamorphic Complex, intruded by Larrie Granodiorite. Intrusive contacts with Illili Suite granites give no clear timing relationships.|16-MAY-23
41848|Papunya Igneous Complex|Age reasons|late Palaeoproterozoic (1640-1635 Ma). Gabbro at 23o16'29.20" S, 131o41'48.44"E has a SHRIMP U-Pb zircon date of 1637 +/- 2 Ma (Hoatson and Clauoe-Long 2002). A metagabbro at 23o18'11.48"S, 131o48'43.44"E has a SHRIMP U-Pb zircon date of 1635 +/- 5 Ma (Hoatson and Clauoe-Long 2002). A gabbro within a pyroxenite body at 23o17'25.59"S, 131o42'04.91"E has a SHRIMP U-Pb zircon date of 1639 +/- 2 Ma (Hoatson and Clauoe-Long 2002).|16-MAY-23
41848|Papunya Igneous Complex|Correlations|Intruded at a similar time to the largely mafic Andrew Young Igneous Complex in MOUNT DOREEN and MOUNT RENNIE, but is geochemically distinct.|16-MAY-23
41848|Papunya Igneous Complex|Comments|Variably recrystallised and metamorphosed at granulite and amphibolite facies during the 1640-1635 Ma Liebig and 1590-1560 Ma Chewings Orogenies respectively.|16-MAY-23
41848|Papunya Igneous Complex|References|Hoatson DM and Claoue-Long J, 2002. Event chronology and prospectivity of the mafic magmatic systems in the Arunta Province. Northern Territory Geological Survey, Record 2002-003. **Hoatson DM and Stewart AJ, 2001. Field investigations of Proterozoic mafic-ultramafic intrusions in the Arunta Province, central Australia. Geoscience Australia, Record 2001/39. **Ranford LC, 1969. Mount Liebig, Northern Territory (First Edition). 1:250 000 geological map series explanatory notes, SF52-16. Bureau of Mineral Resources, Australia. **Scrimgeour IR, Close DF & Edgoose CJ, in prep. Mount Liebig, Northern Territory (Second Edition) 1:250 000 geological map series explanatory notes, SE 52-16. Northern Territory Geological Survey, Darwin.|16-MAY-23
41849|Peculiar Complex|Name source|Mount Peculiar 23o 26' 00" S, 131o 16' 00" E, MOUNT LIEBIG.|16-MAY-23
41849|Peculiar Complex|Unit history|Previously included within undifferentiated gneiss, schist, amphibolite, quartzite, granite, dolerite and pegmatite and undifferentiated granite of Ranford (1969)|16-MAY-23
41849|Peculiar Complex|Geomorphic expression|Low bouldery and rubbly hills and outcrops.|16-MAY-23
41849|Peculiar Complex|Type section locality|Outcrop of flow-banded rhyolite 10 km west-northwest of Mount Peculiar at location 23o23?18.00?S 131o11?00.97? (WGS 84), MOUNT LIEBIG. Reference locality for sediments is at 23o22'31.47?S 131o12?02.21?E, leucogranite at 23o21' 59.52" S, 131o11' 39.43" E|16-MAY-23
41849|Peculiar Complex|Description at type locality|Grey, very fine-grained to microcrystalline quartz-K-feldspar rhyolite with minor muscovite and disseminated Fe-oxides, with swirly flow-banded texture that is generally only visible on weathered surfaces.|16-MAY-23
41849|Peculiar Complex|Extent|In area of low hills north of Mount Peculiar and Mount Putardi and west of Mount Palmer in central MOUNT LIEBIG.|16-MAY-23
41849|Peculiar Complex|Thickness range|n/a, but thickness of flow-banded rhyolite is likely to be >200 metres.|16-MAY-23
41849|Peculiar Complex|Lithology|Flow banded rhyolite, quartz-muscovite schist, equigranular leucogranite, laminated  iron- and manganese-rich metasediment, minor calc-silicate rock and biotite schist.|16-MAY-23
41849|Peculiar Complex|Depositional environment|Rhyolite is interpreted to be a subaerial rheomorphic ignimbrite or long lava flow.|16-MAY-23
41849|Peculiar Complex|Relationships and boundaries|Faulted contact with Lizard Schist and Talipata Granite. Interpreted to be intruded by Udor Granite. Intruded by Stuart Pass Dolerite (Warren and Shaw 1995) and unconformably overlain by Heavitree Quartzite.|16-MAY-23
41849|Peculiar Complex|Age reasons|late Palaeoproterozoic. Flow-banded rhyolite from the type locality has a SHRIMP U-Pb zircon age of 1680 +/- 4 Ma (Cross et al in prep).|16-MAY-23
41849|Peculiar Complex|Correlations|May have correlatives within 1690-1660 Ma felsic migmatites of the Glen Helen Metamorphics (Warren and Shaw 1995) in HERMANNSBURG and eastern MOUNT LIEBIG.|16-MAY-23
41849|Peculiar Complex|Comments|Interpeted to be a succession of volcanic rhyolites with subvolcanic intrusives, along with  minor intercalated sediments. Rhyolite and leucogranite are geochemically indistinguishable. Metamorphosed to lower to middle amphibolite facies during the 1590-1560 Ma Chewings Orogeny.|16-MAY-23
41849|Peculiar Complex|References|Cross A, Claoue-Long J, Scrimgeour IR, Close DF & Edgoose CJ, in prep. NTGS-GA Geochronology project, Report 6. Northern Territory Geological Survey, Record  **Ranford LC, 1969. Mount Liebig, Northern Territory (First Edition). 1:250 000 geological map series explanatory notes, SF52-16. Bureau of Mineral Resources, Australia. **Scrimgeour IR, Close DF & Edgoose CJ, in prep. Mount Liebig, Northern Territory (Second Edition) 1:250 000 geological map series explanatory notes, SE 52-16. Northern Territory Geological Survey, Darwin. **Warren RG and Shaw RD 1995. Hermannsburg, Northern Territory (Second Edition). 1:250 000 geological map series explanatory notes, SF-53-13. Northern Territory Geological Survey, Darwin.|16-MAY-23
24454|Peppimenarti Granite|Name source|Name derived from Peppimenarti Aboriginal Settlement, Daly River Aboriginal Reserve. Peppimenarti is situated within the outcrop area, and translates as "Big Rock".|16-MAY-23
24454|Peppimenarti Granite|Unit history|Previously undivided from the "Litchfield Complex", a blanket term for all the granitoids of the Litchfield Province (Morgan, 1972).|16-MAY-23
24454|Peppimenarti Granite|Type section locality|As above, centred around 14o08'S, 130o04'E.|16-MAY-23
24454|Peppimenarti Granite|Extent|The granitoid crops out over about 3 km2 on the north side of Tom Turners Creek, in an area bounded by the AMG co-ordinates 154375, 177375, 154365, 177363. A smaller outcrop (250 m2) is  south of Tom Turners Creek at AMG coordnates 138345.|16-MAY-23
24454|Peppimenarti Granite|Lithology|Ranges in composition from adamellite to granite; also includes aplitic and pegmatitic phases. The adamellite is a coarse grained, equigranular rock consisting of plagioclase, K-feldspar, quartz and biotite. The granite is fine to medium grained and consists of quartz, K-feldspar and plagioclase in an interlocking granular mosaic. The granitoid is pervasively altered, with sericite and chlorite forming the dominant secondary mineral phases.|16-MAY-23
24454|Peppimenarti Granite|Relationships and boundaries|Overlain unconformably by quartzarenites of the Middle Proterozoic Moyle River Formation. Intruded by the Middle (Late?) Proterozoic Murrenja Dolerite, although this relationship is interpreted from other evidence as it is not clearly demonstrated in the field. Host rocks obscured by cover.|16-MAY-23
24454|Peppimenarti Granite|Age reasons|U-Pb dating of both the Wagait and Murra-Kamangee Granaitoids puts this event at 1840-1850 Ma (page and others, 1984).|16-MAY-23
24454|Peppimenarti Granite|Correlations|The Peppimenarti Granite is separated from the Early Proterozoic Murra-Kamangee Granodiorite to the east and the Wagait Granite to the north by Younger sedimentary sequences. It has the same field relationships with other units as the two abovementioned granitoids. Geochemically, the Peppimenarti Granite is similar to the Wagait Granite. Therefore all three granitoids are believed to have crystallised during the same intrusive event.|16-MAY-23
24454|Peppimenarti Granite|Proposed publication|Moyle, Northern Territory - 1:100 0000 Geological Map Series. Northern Territory Geological Survey, Explanatory Notes, SD 52-11 4969.|16-MAY-23
24454|Peppimenarti Granite|Comments|Reserved. Updated 24/4 to YE|16-MAY-23
24454|Peppimenarti Granite|Category|2|16-MAY-23
24454|Peppimenarti Granite|Proposer|Edgoose C.J.|16-MAY-23
24455|Perenti Metamorphics|Name source|Perenti copper prospect, locality at approximately GR NR033104 (latitude 22o30'S, longitude 135o02'E) (Huckitta 1:250 000).|16-MAY-23
24455|Perenti Metamorphics|Geomorphic expression|Topographic expression and airphoto characteristics: Generally forms low ridges within the Mount Swan Granite. Distinguishing features are a lighter tone on airphoto, and the presence of pronounced layering.|16-MAY-23
24455|Perenti Metamorphics|Type section locality|Generally along a traverse 2 km west of Tower Rock, from GR NR067148 (latitude 22o28'S, longitude 135o04'E) to GR NR067156 on Huckitta. The structure and hence sequence of the unit is not defined and the top and base are not known.|16-MAY-23
24455|Perenti Metamorphics|Extent|On Huckitta, near western edge of sheet area and on Alcoota, near eastern boundary of sheet name. :Mostly as outcrops isolated from each other by granite.|16-MAY-23
24455|Perenti Metamorphics|Lithology|Quartzofeldspathic gneiss, felsic granulite, quartz-sillimanite-biotite-cordierite rocks, calc-silicate rock, metadolerite. Felsic granulite consists of orthoclase, antiperthite and orthopyroxene; calc-silicate rocks consist of diopside, calcic plagioclase and quartz with lesser orthopyroxene, sphene and apatite; metadolerite is fine-grined, consists of hornblende-orthopyroxene-clinopyroxene and has a granulite texture. Generally consists of mineral assemblage with granulite metamorphic grade, later partly retrogressed to amphibolite facies and subsequently hydrated at a still lower grade.|16-MAY-23
24455|Perenti Metamorphics|Identifying features|Outcrops of generally felsic gneiss or granulite mostly associated with or occurring as rafts within the Mount Swan Granite. Pronounced layering is present in most outcrops.|16-MAY-23
24455|Perenti Metamorphics|Age reasons|The age is unknown but is inferred to be early Proterozoic and older than about 1.8 Ga.|16-MAY-23
24455|Perenti Metamorphics|Correlations|No definite correlate known but assigned to Division 2 of the Arunta orogenic domain because of its dominantly felsic composition.|16-MAY-23
24455|Perenti Metamorphics|Proposed publication|NT Geological Survey - Huckitta 1:250 000 Explan. Notes Ed. 2|16-MAY-23
24455|Perenti Metamorphics|Proposer|Warren R.G., Freeman M.J.|16-MAY-23
15094|Pertatataka Formation|Type section locality|The type section of Prichard & Quinlan (1962) as originally designated (3 miles W of Ellery Creek) is retained.|16-MAY-23
15094|Pertatataka Formation|Identifying features|The Pertatataka Formation of Prichard & Quinlan (1962) is redefined here because the original definition has not been followed by subsequent authors (apparently unknowingly). To revert to the original definition now would cause considerable confusion. The type section as originally designated (Section W of Ellery Creek) is retained. The top of the Pertatataka Formation is taken as the base of the Julie Formation (former Julie Member), i.e., at the incoming of the first dolomite or limestone. The base of the formation is put at the top of the Pioneer Sandstone. The formation is predominantly red and green siltstone, shale and feldspathic sandstone.|16-MAY-23
15094|Pertatataka Formation|Defn author|Preiss, W.V., Walter M.R., Coats R.P., Wells A.T., 1978|16-MAY-23
15094|Pertatataka Formation|Proposed publication|BMR Journal|16-MAY-23
15094|Pertatataka Formation|References|Prichard & Quinlan (1962), BMR Report 61.|16-MAY-23
15094|Pertatataka Formation|Status|1|16-MAY-23
15139|Phillips Creek Sandstone|Name source|Phillips Creek, latitude 14o10'S, longitude 132o10'E Katherine 1:100 000 Sheet area.|16-MAY-23
15139|Phillips Creek Sandstone|Unit history|Previously called the Phillips Creek Member of the Edith River Volcanics by Walpole & others (1968).|16-MAY-23
15139|Phillips Creek Sandstone|Type section locality|200 m thick sequence on north side of Phillips Creek from GR 930263 (bottom) to GR 933262 (top) Katherine 1:100 000 Sheet area.|16-MAY-23
15139|Phillips Creek Sandstone|Extent|A semi-continuous ridge forming the western edge of the Edith Basin between 3 km north of Edith Falls and 2 km northeast of O'Shea Hill (Katherine).|16-MAY-23
15139|Phillips Creek Sandstone|Thickness range|Up to 300 m.|16-MAY-23
15139|Phillips Creek Sandstone|Lithology|Purple medium sandstone, conglomerate, red and purple shales and tuffaceous sediments.|16-MAY-23
15139|Phillips Creek Sandstone|Relationships and boundaries|Unconformably overlies the Tollis Formation, conformably overlain by the Plum Tree Creek Volcanics. A basal unit of the Edith River Group probably equivalent to the Kurrundie and Hindrance Creek Sandstones.|16-MAY-23
15139|Phillips Creek Sandstone|Age reasons|Late Early Proterozoic (1780-1650 m.y.) as the Group unconformably overlies the Cullen Granite Complex (1780-1730 m.y.) and is older than the Kombolgie Formation (1650 m.y.)|16-MAY-23
15139|Phillips Creek Sandstone|Proposed publication|Geological map Commentary. Geology of the Edith River Region 1:100 000 scale|16-MAY-23
15139|Phillips Creek Sandstone|Status|1|16-MAY-23
26103|Pine Hill Formation|Name source|Pine Hill homestead (5553-996231), in the southwest of the Tea Tree 1:100 000 Sheet area.|16-MAY-23
26103|Pine Hill Formation|Unit history|Called Ironbark Silts by Australian Geophyhsical (1967); included in 'Meta-sediments and acid metamorphics of uncertain origin' of Evans & Glikson (1969); mapped as 'Precambrian schist metasediments, including marble' by Wells & others (1971).|16-MAY-23
26103|Pine Hill Formation|Type section locality|AX-2, 3 km east of Mount Thomas, immediately above type section of Mount Thomas Quartzite, in Reynolds Range. Base at 5453-761313, top at -756311, Not measured.|16-MAY-23
26103|Pine Hill Formation|Extent|Entire length of Reynolds Range, in Reynolds Range, Tea Tree, and Aileron 1:100 000 Sheet areas; Giles Range, in Reynolds Range and Denison 1:100 000 Sheet areas; also in Wabudali Range Mount Theo 1:250 000 Sheet area.|16-MAY-23
26103|Pine Hill Formation|Thickness range|570 m in type section (estimated from airphoto measurement and dip information); apparently fairly constant along entire Reynolds Range.|16-MAY-23
26103|Pine Hill Formation|Lithology|In type section, weakly cleaved red-brown to grey-green shale, siltstone, and fine-grained silty sandstone, grading to slate, with porphyroblasts of andalusite. A distinctive pair of marker beds occurs near the middle of the section, comprising a white orthoquartzite below, and blue hematite quartzite above, the two separated by a few metres of shale. Two thin sills of microgranite retrogressively metamorphosed to orthoschist of Warimbi Schist are present in lower part of section.|16-MAY-23
26103|Pine Hill Formation|Relationships and boundaries|Conformably overlies and interfingers with Mount Thomas Quartzite; no overlying formation known. Includes conformable Algamba Dolomite Member and Woodforde River beds. Intruded by sills of retrogressively metamorphosed microgranite of Warimbi Schist, and by Napperby Gneiss.|16-MAY-23
26103|Pine Hill Formation|Age reasons|Older than 1800 to 1500 m.y. age of Napperby Gneiss; preliminary Rb-Sr isotopic date on slate from northwest part of Reynolds Range gives time of metamorphism as 1500 m.y. (L P Black, BMR, personal communication, 1977). Hence Formation is Middle Proterozoic or older.|16-MAY-23
26103|Pine Hill Formation|Proposed publication|Stratigraphic definitions in Arunta Block' - BMR Microfiche Report.|16-MAY-23
26103|Pine Hill Formation|Defn Reference|80/20787|16-MAY-23
26103|Pine Hill Formation|Name first published by|Offe L.A., Stewart A.J., 1977|16-MAY-23
26103|Pine Hill Formation|Reserved? Yes/No|Yes|16-MAY-23
15284|Pioneer Sandstone|Name source|Pioneer Creek, which flows into Ormiston Creek near Glen Helen Tourist Camp, Hermannsburg 1:250 000 Sheet area.|16-MAY-23
15284|Pioneer Sandstone|Unit history|This is the upper member of the Areyonga Formation of Prichard & Quinlan (1962) and subsequent authors.|16-MAY-23
15284|Pioneer Sandstone|Type section locality|170 metres of sandstone with minor dolomite in the bed of Ellery Creek, 1.0-1.3 km south of Ellery Creek Big Hole at 133o04'12", 23o47'24", Hermannsburg 1:250 000 Sheet area. The base is put at the first sandstone above the Areyonga Formation and the top is put at the top of the pink dolomite into which the sandstone grades.|16-MAY-23
15284|Pioneer Sandstone|Extent|The formation is exposed on the Henbury, Hermannsburg, Alice Springs and probably Rodinga 1:250 000 Sheet areas.|16-MAY-23
15284|Pioneer Sandstone|Thickness range|170 m in the type section, and similar elsewhere. |16-MAY-23
15284|Pioneer Sandstone|Lithology|Sandstone, white to brown, friable, medium to coarse grained, cross-bedded, feldspathic. The uppermost 8 m are silicified and outcrop prominently. Erosional scours in the uppermost sandstone are filled with lenses of dolomite about 10 cm thick; this is pink and contains erect columnar stromatolites. The sandstone grades up into pale pinkish grey dolomite with cross-cutting red chert nodules and lenses. In much of the Alice Springs 1:250 000 Sheet area the formation is conglomeratic.|16-MAY-23
15284|Pioneer Sandstone|Relationships and boundaries|Overlies the Areyonga Formation and Bitter Springs Formation with inferred disconformity. Conformably overlain by the Pertatataka Formation.|16-MAY-23
15284|Pioneer Sandstone|Age reasons|The Pioneer Sandstone is a probable correlative of the Olympic Formation, the upper tillite of the Amadeus Basin. By correlation with the Adelaide Geosyncline, it is late Adelaidean.|16-MAY-23
15284|Pioneer Sandstone|Defn author|Preiss W.V., Walter M.R., Coats R.P., Wells A.T., 1978|16-MAY-23
15284|Pioneer Sandstone|Proposed publication|BMR Journal|16-MAY-23
39078|Pitjantjatjara Supersuite|Name source|Anangu Pitjantjatjara Lands, northern South Australia.|16-MAY-23
39078|Pitjantjatjara Supersuite|Unit history|Kulgera Suite (Major and Conor 1993), Kulgera Supersuite (Budd et al 1996)|16-MAY-23
39078|Pitjantjatjara Supersuite|Constituents|NT - Pottoyu Suite*, Umutju Suite, Kulpitjata Suite, unnamed granites in the Umbeara region, Ayers Range Granite, Kulgera Granite, Mantarurr Suite, Walal Granite; SA ? Ernabella Adamellite Suite, Ngarinya Adamellite and unnamed granite (Camacho 1997); unnamed granite in the Tompkinson Ranges area; unnamed and undivided granite in SA will include constituents which cannot be identified at this stage; WA ? unnamed granite in the Tompkinson Ranges area; other unnamed and undivided granite in WA will include constituents which cannot be identified at this stage.|16-MAY-23
39078|Pitjantjatjara Supersuite|Geomorphic expression|Low rounded hills with numerous boulders, tors and pavements. Low bouldery rises and scattered pavements.|16-MAY-23
39078|Pitjantjatjara Supersuite|Type section locality|Type localities are described within definitions of constituent units|16-MAY-23
39078|Pitjantjatjara Supersuite|Extent|Widespread across Musgrave Block in the Northern Territory. Present in the Musgrave Block in northern SA and in WA but extent of distribution at this stage is unknown.|16-MAY-23
39078|Pitjantjatjara Supersuite|Lithology|Biotite +/- hornblende granite, monzonite. Often porphyritic, sometimes includes rapakivi textures. Division into constituent units is based on field criteria, location and composition/geochemistry.|16-MAY-23
39078|Pitjantjatjara Supersuite|Relationships and boundaries|Intrudes gneiss with protolith ages in the range 1600-1540 Ma which was metamorphosed and deformed during the 1200-1160 Ma Musgrave Orogeny. Intruded by the 1080 Ma Alcurra Dolerite, 1000 Ma dolerite and the 800 Ma Amata Dykes. Unconformably overlain by the c. 850 Ma Dean Quartzite of the Amadeus Basin.|16-MAY-23
39078|Pitjantjatjara Supersuite|Age reasons|SHRIMP U-Pb zircon ages in the range 1190-1120 Ma (Edgoose et al 1993, Major and Conor 1993, Scrimgeour et al 1999, Edgoose et al 2002, Young et al 2002, Close et al 2003).|16-MAY-23
39078|Pitjantjatjara Supersuite|Proposed publication|Edgoose et al 2003|16-MAY-23
39078|Pitjantjatjara Supersuite|Comments|* The terms Granite Suite and Granite Complex have been replaced with Suite for the constituent members for ease of reference. These granites and granite suites have been grouped into a supersuite on the basis that they formed through substantial melting of crustal rocks during and immediately postdating the 1200-1160 Ma Musgrave Orogeny. Granites of this age in the Musgrave Block have previously been referred to as the Kulgera Suite (Major and Conor 1993) or Kulgera Supersuite (Budd et al 1996). The term Kulgera Adamellite/Granite has prior usage, however, hence the requirement for a new name.|16-MAY-23
39078|Pitjantjatjara Supersuite|References|Budd A, Wyborn L and Bastrakova I, 2002. The metallogenic potential of Australian Proterozoic granites. Australian Geological Survey Organisation, Record 2001 012. **Camacho A, 1997. An isotopic study of deep-crustal orogenic processes, Musgrave Block, central Australia. PhD thesis, Australian National University, Canberra. **Close DF, Edgoose CJ and Scrimgeour IR,  2003. Hull and Bloods Range Special, Northern Territory (First Edition). 1:100 000 geological map series explanatory notes, SE 53-5. Northern Territory Geological Survey, Darwin. **Edgoose CJ, Camacho A, Wakelin-King, GA and Simons BA, 1993. Kulgera, Northern Territory (Second Edition). 1:250 000 geological map series explanatory notes, SE 53-5. Northern Territory Geological Survey, Darwin. **Edgoose CJ, Close DF, Stewart AJ and Duncan N, 2002. Umbeara, Northern Territory (First Edition). 1:100 000 geological map series explanatory notes, SE 53-5. Northern Territory Geological Survey, Darwin. **Edgoose CJ, Scrimgeour IR and Close DF, 2003. The geology of the Musgrave Block, Northern Territory. Northern Territory Geological Survey, Report 15. **Major RB and Conor CHH, 1993. Musgrave Block: in Drexel JF, Preiss WV and Parker AJ (editors) The geology of South Australia, Volume 1, The Precambrian. Bulletin 54. S.A. Dept of Mines and Energy, Adelaide. **Scrimgeour IR, Close DF and Edgoose CJ, 1999. Petermann Ranges, Northern Territory (Second Edition). 1:250 000 geological map series explanatory notes, SE 53-5. Northern Territory Geological Survey, Darwin. **Young DN, Duncan N, Camacho A, Ferenzi PA and Madigan TLA, 2002. Ayers Rock, Northern Territory (Second Edition). 1:250 000 geological map series explanatory notes, SE 53-5. Northern Territory Geological Survey, Darwin.|16-MAY-23
15306|Plain Creek Formation|Name source|From Plain Creek, a minor creek which drains north from the Carrara Range in southeastern MOUNT DRUMMOND.|16-MAY-23
15306|Plain Creek Formation|Name source|From Plain Creek, a tributary of the South Nicholson River, which drains the northwestern Carrara 1:100 000 Sheet area (Sheet 6460), Northern Territory.|16-MAY-23
15306|Plain Creek Formation|Unit history|Previously mapped as part of the Bluff Range beds on the first edition of MOUNT DRUMMOND by Smith and Roberts (1963). Delineated and mapped as Plain Creek Formation on the Carrara Range region 1:100 000 sheet by Sweet (1984).|16-MAY-23
15306|Plain Creek Formation|Geomorphic expression|Forms plains and undulating low hills. Several sandstone interbeds form higher ridges in some sections.|16-MAY-23
15306|Plain Creek Formation|Type section locality|Sixteen kilometres northwest of Mount Drummond, in the northwestern Carrara 1:100 000 Sheet area. The base is at grid ref. 676444, and the top is at grid ref. 673453. It consists of 600 m of interbedded sandstone and micaceous siltstone and shale.|16-MAY-23
15306|Plain Creek Formation|Type section locality|Location unchanged from that nominated by Sweet (1982), but base begins approximately 50 m stratigraphically higher, at the top of the Shady Bore Quartzite. Base now at 767626E 7944717N (latitude 18o 34.3'S longitude 137o 32.1'E), and the top remains at 767426E 7945467N (latitude 18o33.9'S longitude 137o32.0'E).|16-MAY-23
15306|Plain Creek Formation|Extent|A series of east to northeast-trending strike ridges in the northeastern Mitchiebo and northern Carrara 1:100 0000 Sheet areas.|16-MAY-23
15306|Plain Creek Formation|Extent|Southeastern part of MOUNT DRUMMOND, in the Carrara Range, and 10 km to the north, between the South Nicholson River and Cleanskin Creek.|16-MAY-23
15306|Plain Creek Formation|Thickness range|550 m in the type section and 400 m in the Maloney Creek Inlier, 16 km north of the type seciton; 1000 m in the Bluff Range, although there is a possibility of fault repetition in that section.|16-MAY-23
15306|Plain Creek Formation|Lithology|The unit is characterised by micaceous siltstone and shale, with at least 3 interbeds of fine to medium, well sorted, quartz-rich sandstone. The formation thickens eastwards and contains a higher proportion of sand in the sequence. It is virtually non-dolomitic in all areas.|16-MAY-23
15306|Plain Creek Formation|Lithology|Cycles of shale or laminated siltstone, grading up through laminated and thin-bedded very fine-grained lithic sandstone to thin to medium beds of very fine or fine-grained sandstone. Rarely, medium to coarse-grained sandstone, some with mudstone intraclasts, is present in the upper parts of cycles. Thin to thick graded sandstone and cobble to boulder-bearing pebbly mudstone interbeds in northern outcrops.|16-MAY-23
15306|Plain Creek Formation|Depositional environment|Storm-dominated shelf, and probable fan-delta facies in northern outcrops.|16-MAY-23
15306|Plain Creek Formation|Relationships and boundaries|Both the lower and upper contacts of the Plain Creek Formation are conformable; they are marked by a rapid transition from siltstone to sandstone (base) and sandstone to siltstone (top). The sandstone defining the base of the formation is a massive, medium-grained orthoquartzite unit about 50 m thick in the type section.|16-MAY-23
15306|Plain Creek Formation|Relationships and boundaries|Overlies Shady Bore Quartzite, apparently conformably - the boundary is sharply gradational over a few metres. The upper contact, with the Lawn Hill Formation, is invariably concealed but is concordant and presumed to be conformable. Parent unit: McNamara Group.|16-MAY-23
15306|Plain Creek Formation|Age reasons|Proterozoic,Carpentarian - correlated with sequences of known Carpentarian age by Plumb & Derrick (1975) and Hutton & Sweet (1982, in press).|16-MAY-23
15306|Plain Creek Formation|Age reasons|Palaeoproterozoic, late Statherian. Based on correlations (see below) it is around 1640-1630 Ma.|16-MAY-23
15306|Plain Creek Formation|Correlations|The Plain Creek Formation is correlated with the Riversleigh Siltstone and Termite Range Formation in the Lawn Hill region, 100 km to the east (Sweet 1984, Rawlings et al, in prep). These formations yield ages in the range 1647+/-8 Ma to 1630+/-5 Ma (Page et al 2000).|16-MAY-23
15306|Plain Creek Formation|Defn author|Sweet, I.P. [approved 11-APR-2005]|16-MAY-23
15306|Plain Creek Formation|Proposed publication|BMR Report 242|16-MAY-23
15306|Plain Creek Formation|Comments|This revised definition is necessary as the basal sandstone, Pmas, mapped by Sweet (1984) has been excluded from the formation, and is now mapped separately as Shady Bore Quartzite. The revised Plain Creek Formation consists of those rocks above the Shady Bore Quartzite, and retains/maintains the essential character of the unit - a predominantly fine-grained, siliciclastic formation. Note: All locations are based on the GDA94 geodetic datum. Standard series 1:250 000 sheet names are shown in upper case.|16-MAY-23
15306|Plain Creek Formation|References| **RAWLINGS D.J. Sweet I.P. and Kruse P.D., in prep [2008]. Mount Drummond, Northern Territory (Second Edition); 1:250 000 Geological Map Series, sheet SE53-12. Northern Territory Geological Survey, Map and Explanatory Notes.    **SMITH J.W. and Roberts H.G., 1963. Mount Drummond, N.T. (First Edition); 1:250,000 geological series, sheet SE53-12. Bureau of Mineral Resources, Geology and Geophysics, Map and Explanatory Notes.   **SWEET I.P., 1982. Definition of new stratigraphic units in the Carrara Range region. Bureau of Mineral Resources, Geology and Geophysics, Report, 242.   **SWEET I.P., 1984. Carrara Range region, Northern Territory (First Edition); 1:100,000 geological series, portions of sheets 6460 and 6360. Bureau of Mineral Resources, Geology and Geophysics, Explanatory Notes.|16-MAY-23
15306|Plain Creek Formation|Defn approved by|Brakel A.T. (subject to Hutton & Sweet reference details being entered when available)|16-MAY-23
15306|Plain Creek Formation|Defn Reference|83/23538|16-MAY-23
15306|Plain Creek Formation|First Reference|82/12103 Fig. 3|16-MAY-23
15306|Plain Creek Formation|Proposer|Sweet I.|16-MAY-23
37727|Playford Sandstone|Name source|From the Playford River, which drains southwards from the Mitchiebo Waterhole area and in the Mount Drummond 1:250 000 sheet area.|16-MAY-23
37727|Playford Sandstone|Unit history|Previously mapped as Constance Sandstone on the first edition of Mount Drummond by Smith and Roberts (1963). Most of it also mapped as Constance Sandstone by Sweet (1984) on the Carrara Range region 1:100 000 sheet, except for the basal part adjacent to Western Creek, which was included in the underlying Widdallion Sandstone Member of the Lawn Hill Formation, McNamara Group.|16-MAY-23
37727|Playford Sandstone|Constituents|Subdivided into three members in the type section - from oldest to youngest Wangalinji Member, Top Lily Sandstone Member, and No Mans Sandstone Member. The two older members can be traced through most outcrops, but the No Mans Sandstone Member is recognised only in the type section and in outcrops to the east of it.|16-MAY-23
37727|Playford Sandstone|Geomorphic expression|A series of low sandstone ridges with intervening valleys underlain by finer-grained components of the formation.|16-MAY-23
37727|Playford Sandstone|Type section locality|In the area 4 km southeast of Mitchiebo Waterhole, MOUNT DRUMMOND, and is easily accessible from the Mittiebah-Wangalinji access road. The section runs from south to north: base is at latitude 18o39'57''S longitude 137o7'38''E (724360E 7934820N). The top is 1.4 km north, at latitude 18o39'10''S longitude 137o7'33''E (724230E 7936260N).|16-MAY-23
37727|Playford Sandstone|Extent|South-central and southwestern Mount Drummond 1:250 000 sheet area, and one isolated outcrop in the northwest in the headwaters of Benmara Creek.|16-MAY-23
37727|Playford Sandstone|Thickness range|From 390 m in the type section, to at least 1450 m in the Playford Anticline, 13 km to the northwest.|16-MAY-23
37727|Playford Sandstone|Lithology|Very coarse-grained to granule quartz-rich sandstone at base, overlain by interbedded laminated shale with thin-bedded siltstone and very fine-grained lithic sandstone, coarse-grained quartz sandstone interbeds. Thick to very thick bedded, large-scale cross bedded, very fine- to fine-grained, well-sorted lithic sandstone, minor ferruginous sandstone, ironstone, and stromatolitic carbonates, and strongly trough-cross-bedded, fine- to coarse-grained quartz-rich sandstone with granule to pebble lags.|16-MAY-23
37727|Playford Sandstone|Depositional environment|Shallow marine shelf, mainly tide-dominated and nearshore; minor deeper water, storm-dominated facies.|16-MAY-23
37727|Playford Sandstone|Relationships and boundaries|Lies with angular unconformity on the Widdallion Sandstone Member of the Lawn Hill Formation 6.5 km SW of Mitchiebo Waterhole (717310E 7932906N), and disconformably on the same formation over a strike length of some 50 km to the east of the Mitchiebo Waterhole outcrops. The contact is placed at the change from highly lithic, dark-coloured sandstone below, to light-coloured coarse to granule-rich or pebbly, sublithic sandstone (Playford). The formation is overlain conformably in virtually all outcrops by the Crow Formation. Where seen the contact is a rapid transition over a few metres into fine-grained siliciclastic rocks. Parent units: Wild Cow Subgroup, South Nicholson Group.|16-MAY-23
37727|Playford Sandstone|Age reasons|A maximum age of 1591+/-10 Ma, based on reworked tuffaceous material from the underlying Lawn Hill Formation (Page et al 2000) in LAWN HILL, or 1595+/-6 Ma based on tuffs in the Lawn Hill Formation in the same area (Page and Sweet 1998). The interpreted age range of 1500-1400 Ma for the South Nicholson Group is based on its correlation with the Roper Group of the southern McArthur Basin (Dunn et al 1966; Plumb & Derrick 1975). Ages of 1492+/-4 and 1493+/-4 Ma for tuffaceous material from the Mainoru Formation in the Roper Group (Jackson et al 1999) provides the most reliable estimate for the age of the lower part of that Group, and hence for the Playford Sandstone or its members.|16-MAY-23
37727|Playford Sandstone|Correlations|None known, but it is likely that sandstones low in the Renner Group (Hussey et al 2001) and the Roper Group (Jackson et al 1999) are in part correlative, given the overall correlation between these groups.|16-MAY-23
37727|Playford Sandstone|Defn author|Sweet, I.P. [11-APR-2005]|16-MAY-23
37727|Playford Sandstone|Comments|Basal formation of the Wild Cow Subgroup, and of the South Nicholson Group as a whole. Note: All locations are based on the GDA94 geodetic datum. Standard series 1:250 000 sheet names are shown in upper case.|16-MAY-23
37727|Playford Sandstone|References|**DUNN P.R., Plumb K.A. and Roberts H.G. 1966. A proposal for time-stratigraphic subdivision of the Australian Precambrian. Journal of the Geological Society of Australia, 13, 593-608.  **HUSSEY K.J., Beier P.R., Crispe A.J., Donnellan N. and Kruse P.D. 2001. Helen Springs, Northern Territory (Second Edition); 1:250 000 geological series, sheet SE53-10.   **JACKSON M.J., Sweet I.P., Page R.W. and Bradshaw B.E., 1999. The South Nicholson and Roper Groups: evidence for the early Proterozoic Roper Superbasin. In: Bradshaw B.E. and Scott D.L. (Eds.), Integrated basin analysis of the Isa Superbasin using seismic, well-log and geopotential data: an evaluation of the economic potential of the northern Lawn Hill Platform. Australian Geological Survey Organisation, Record 1999/19 (unpaginated).    **PAGE R.W., Jackson M.J. and Krassay A.A., 2000. Constraining sequence stratigraphy in north Australian basins: SHRIMP U-Pb zircon geochronology between Mt Isa and McArthur River. Australian Journal of Earth Sciences, 47, 3; 431-459.  **PAGE R.W. and Sweet I.P., 1998. Geochronology of basin phases in the western Mount Isa Inlier, and correlation with the McArthur Basin. Australian Journal of Earth Sciences, 45, 2; 219-232.  **PLUMB K.A. and Derrick G.M., 1975. Geology of the Proterozoic rocks of the Kimberley to Mount Isa Region. In Knight C.L. (Editor), Economic Geology of Australia and Papua New Guinea, 1. Metals. The Australasian Institute of Mining and Metallurgy, Monograph Series, 5, 217-252.  **SMITH J.W. and Roberts H.G., 1963. Mount Drummond, N.T. (First Edition); 1:250,000 geological series, sheet SE53-12. Bureau of Mineral Resources, Geology and Geophysics, Map and Explanatory Notes.  **SWEET I.P., 1984. Carrara Range region, Northern Territory (First Edition); 1:100,000 geological series, portions of sheets 6460 and 6360. Bureau of Mineral Resources, Geology and Geophysics, Explanatory Notes.|16-MAY-23
37959|Plenty Group|Name source|From the Plenty Highway, which passes near outcrop of Yackah beds at Mount Cornish in southeastern HUCKITTA.|16-MAY-23
37959|Plenty Group|Unit history|Part of Field River beds of Smith (1963a) and Central Mount Stuart beds of Smith and Milligan 1964); Amesbury Quartzite Member of Central Mount Stuart Formation (Offe 1978).Distribution: HUCKITTA, BARROW CREEK and MOUNT PEAKE.|16-MAY-23
37959|Plenty Group|Constituents|Yackah beds, Amesbury Quartzite.|16-MAY-23
37959|Plenty Group|Extent|HUCKITTA, BARROW CREEK and MOUNT PEAKE.|16-MAY-23
37959|Plenty Group|Relationships and boundaries|Nonconformably overlies Jervois Granite in HUCKITTA, Mount Dobbie Granite in HAY RIVER, Palaeo-Mesoproterozoic granitoids and metamorphic rocks in BARROW CREEK and MOUNT PEAKE. Disconformable beneath Aroota Group: Mount Cornish Formation in HUCKITTA and Yardida Tillite in HAY RIVER. Unconformable beneath Keepera Group: Boko Formation and Central Mount Stuart Formation in BARROW CREEK and MOUNT PEAKE.|16-MAY-23
37959|Plenty Group|Age reasons|Stratigraphic position, lithological similarity and mutual occurrence of stromatolite Acaciella australica (Walter 1972, Walter et al 1979) permit correlation with Bitter Springs Formation of Amadeus Basin and confirm an immediate post-800 Ma Cryogenian age. Stratigraphic position beneath the fossiliferous latest Neoproterozoic Central Mount Stuart Formation, together with fault-associated quartz veining (indicating a tectonic imprint and therefore apparently favouring an age early in Georgina Basin developmental history) suggested to Haines et al (1991) a Neoproterozoic or older age for the Amesbury Quartzite.|16-MAY-23
37959|Plenty Group|Correlations|Heavitree Quartzite and Bitter Springs Formation of Amadeus Basin (Walter 1980), Albinia Formation and Vaughan Springs Quartzite of Ngalia Basin (Freeman 1986).|16-MAY-23
37959|Plenty Group|Comments|The utility of this group name relies on the validity of the correlation by Haines et al (1991) of its two constituent formations.|16-MAY-23
15334|Plum Tree Creek Volcanics|Name source|Plum Tree Creek. Latitude 13o35'S, longitude 132o27'E Ranford Hill 1:100 000 Sheet area.|16-MAY-23
15334|Plum Tree Creek Volcanics|Unit history|Includes all areas previously called the Plum Tree Creek Volcanic Member of the Kombolgie Formation and all volcanic units within the Edith River Volcanics on Katherine, and Eva Valley 1:100 000 Sheet areas, mapped by Walpole & others (1968).|16-MAY-23
15334|Plum Tree Creek Volcanics|Type section locality|Between GR 138038 (bottom) to 190050 (top) Ranford Hill 1:100 0000 Sheet area.|16-MAY-23
15334|Plum Tree Creek Volcanics|Extent|Extensive outcrops over an area about 5000 km2 between Katherine, Eva Valley, and El Sherana (Ranford Hill, Mundogie, Stow, Katherine, Eva Valley 1:100 000 Sheet areas.|16-MAY-23
15334|Plum Tree Creek Volcanics|Thickness range|Range 400 to 1000 m.|16-MAY-23
15334|Plum Tree Creek Volcanics|Lithology|Massive pink ignimbrite, miknor pink rhyolite, amygdaloidal basalt, dolerite, felsic tuff. Minor shale and lithic quartz sandstone also present in the Mundogie 1:100 000 Sheet area.|16-MAY-23
15334|Plum Tree Creek Volcanics|Relationships and boundaries|Conformably overlies the Kurrundie Sandstone and Phillips Creek Sandstone where present; otherwise unconformably overlies metamorphosed Early Proterozoic rocks (1800 m.y.) of the Pine Creek Geosyncline, and the Cullen Granite Complex (1780-1730 m.y.). Unconformably or disconformably overlain by Kombolgie Formation (1650 m.y.). Intruded by Grace Creek Granite which appears to be similar in composition and may be cogenetic. Upper unit of the Edith River Group. Contains the Mount Shepherd Rhyolite Member in the Katherine 1:100 000 Sheet area.|16-MAY-23
15334|Plum Tree Creek Volcanics|Age reasons|Late Early Proterozoic (between 1780 to 1650 m.y., see above).|16-MAY-23
15334|Plum Tree Creek Volcanics|Proposed publication|Geological map Commentary Randford Hill 1:100 000 Sheet.|16-MAY-23
15334|Plum Tree Creek Volcanics|Status|1|16-MAY-23
15428|Poodyea Formation|Name source|From Poodyea Point; GR 648148 Glenormiston 1:250 000 Sheet area (22o52'S, 138o13'E).|16-MAY-23
15428|Poodyea Formation|Unit history|The Poodyea Formation was included in the jSiluro-Devonian cravens Peak Beds (by Reynolds) in Smith (1965), Smith (1972); unconsolidated pebble deposits in the Mount Whelan sheet were described by Reynolds (1968) and interpreted as Permian by Smith (1972); "Unit 4-post-Devonian rocks" of Draper (1976); mapped as the Beattie Creek Conglomerate on Toko 1:100 000 (BMR, 1979); "post-Palaeozoic sediments" of Turner et al (1981).|16-MAY-23
15428|Poodyea Formation|Type section locality|An unknown thickness (probably less than 10 m) is exposed in the watershed dividing the upper tributaries of Beattie Creek and Linda Creek, 53K RQ 004666 on Toko 1:100 000 (Sheet 6452), 9 km north of Tobermory Outstation "The Gap". The outcrop has a low, subdued relief and is differentiated from the underlying Carlo Sandstone by its light pinkish-brown appearance on colour aerial photography.|16-MAY-23
15428|Poodyea Formation|Extent|Southwest part of Glenormiston, southeast party of Tobermory, and western area of Mt Whelan 1:250 000 Sheets. The unit occurs within the Toko Range and to the south as narrow discontinuous belts.|16-MAY-23
15428|Poodyea Formation|Lithology|Boulder conglomerate, generally unconsolidated and comprising well-rounded clasts of quartzite, Carlo Sandstone, milky quartz; cross-stratified sandy conglomerate and pebbly sandstone with parting lineation. The cross-strata comprise medium- to large-scale cosets of low, medium and high-angle trough lamination.|16-MAY-23
15428|Poodyea Formation|Relationships and boundaries|Disconformably overlies Early to Middle Ordovician Carlo Sandstone, Ethabuka, Mithaka and Nora Formations, Lower to Middle Devonian Cravens Peak Beds, and possibly (although not observed) Jurassic-Cretaceous Hooray Sandstone. Unknown but presu;med lateral transition with the Tertiary Austral Downs Limestone. Overlain by unconsolidated Quarternary Units.|16-MAY-23
15428|Poodyea Formation|Age reasons|Presumed Tertiary on the following basis as there is no known fauna: 1) The physiographic occurrence in the Toko Range is in canyons incised below the Mesozoic level; 2) Outcrop trends indicate pre-existing valleys down the synclinal axis. These valleys are present and further enhanced in the Carlo Sandstone within the Toko Range but there is inverted relief over the Ethabuka Sandstone and Mithaka Formation terrain; 3) The Unit is locally overlain by Quaternary cover.|16-MAY-23
15428|Poodyea Formation|Proposed publication|BMR Journal|16-MAY-23
15428|Poodyea Formation|Comments|Notes: The Poodyea Formation is defined primarily from airphoto interpretation, the brief description of Unit 4 by Draper (1976), and field observations by Draper on BMR Georgina Basin Data file, CPDMRXWG GBD.|16-MAY-23
15428|Poodyea Formation|Defn approved by|Brakel A.T., Stuart-Smith P., Freeman M.J.|16-MAY-23
15428|Poodyea Formation|Proposer|Radke B.M., Simpson C.J., Draper J.J.|16-MAY-23
15428|Poodyea Formation|Resdate|16-MAR-1982|16-MAY-23
15428|Poodyea Formation|Reserved? Yes/No|Yes|16-MAY-23
15428|Poodyea Formation|State(s)|Qld, NT|16-MAY-23
26321|Possum Creek Charnockite|Name source|Possum Creek (metric grid reference: 296000E, 7541000N), which flows past the type locality of the Possum Creek Charnockite, N. side of Anmatjira Range, Tea Tree 1:100 000 Sheet area.|16-MAY-23
26321|Possum Creek Charnockite|Type section locality|Hill (at metric grid reference 295000E, 7539000N) about 400 m across of Possum Creek Charnockite on SE bank of Possum Creek.|16-MAY-23
26321|Possum Creek Charnockite|Extent|Six separate and discrete masses in SE part of Anmatjira Range, Tea Tree 1:100 000 Sheet area, most 1-2 km across, some smaller.|16-MAY-23
26321|Possum Creek Charnockite|Lithology|Brown, med-gr., foliated, hornblende (brown) - hypersthene-quartz-andesine-sanidine granite with sparse, rapakivi feldspar augen.|16-MAY-23
26321|Possum Creek Charnockite|Relationships and boundaries|Intrudes Tyson Creek granulite (q.v.). Adjoins Aloolya Gneiss (q.v.) but no intrusive relationship seen. Foliation in Charnockite is drag-folded at one contact with Aloolya Gneiss suggesting that Charnockite is deformed by and therefore older than Aloolya Gneiss. However, 1.5 m from contact into Charnockite, vergence of dragfolds reverses across a pegmatite dyke, and so both sets of drag-folds could have been formed by intrusion of pegmatite alone. Retrogressively metamorphosed near Aloolya Gneiss, but this could be deuteric alteration during its own cooling.|16-MAY-23
26321|Possum Creek Charnockite|Identifying features|Reason for Proposed Name: A very distinctive and easily recognised rock-type which forms several mappable bodies in Anmatjira Range.|16-MAY-23
26321|Possum Creek Charnockite|Age reasons|No isotopic date available. Younger than Tyson Creek granulite, probably older than Aloolya Gneiss and therefore older than Anmatjira Orthogneiss (1642 +/- 100 m.y.). Probably Early Proterozoic, and must be late Early Proterozoic or early Middle Proterozoic (Early Carpentarian) if Tyson Creek granulite is Early Proterozoic (as supposed, but not proved).|16-MAY-23
26321|Possum Creek Charnockite|Proposed publication|1. 'Geology of NW Arunta Block, NT' - BMR Publication.  2. 'Stratigraphic definitions in Arunta Block' - BMR Microfiche Report.|16-MAY-23
26321|Possum Creek Charnockite|Defn Reference|80/20787|16-MAY-23
26321|Possum Creek Charnockite|Proposer|Stewart A.J.|16-MAY-23
26321|Possum Creek Charnockite|Reserved? Yes/No|Yes|16-MAY-23
33649|Pottoyu Granite Suite|Name source|Pottoyu Hills, south of Petermann Ranges, Petermann Ranges.|16-MAY-23
33649|Pottoyu Granite Suite|Unit history|Comprises the Pottoyu Granite Complex of Forman (1966a, 1972) and outcrops previously mapped as Olia Gneiss and undifferentiated to the north of the Petermann Ranges and south of the Pottoyu Hills by Forman (1966a, 1966b, 1972).|16-MAY-23
33649|Pottoyu Granite Suite|Constituents|Mulyati Granite, undivided Pottoyui Granite Suite.|16-MAY-23
33649|Pottoyu Granite Suite|Geomorphic expression|Rounded rocky hills covered by tors and boulders.|16-MAY-23
33649|Pottoyu Granite Suite|Type section locality|(1) Coarsely porphyritic granite 25o7'16.6"S, 129o10'49.9"E; (2) Hornblende-bearing granitic gneiss 25o34'48.7"S, 130o1'24.8"E; Equigranular granite 25o21'38.3"S, 129o9'36"E.|16-MAY-23
33649|Pottoyu Granite Suite|Extent|Throughout the Pottoyu Hills, in scattered low outcrops to the south of the Pottoyu Hills, and north of the Petermann Ranges extending onto Bloods Range. Extent to west into Western Australia is not known.|16-MAY-23
33649|Pottoyu Granite Suite|Lithology|Coarsely porphyritic K-feldspar-rich foliated biotite granite, with spherical K-feldspar phenocrysts 1-6 cm in diameter typically with rapakivi textures. The mineral assemblage is quartz, K-feldspar, plagioclase, biotite, sphene and Fe-Ti oxides, with or without allanite, epidote and hornblende. Less abundant K-feldspar-rich medium to fine grained equigranular biotite granite and aplite occurs. A gneissic texture with partial melting and coarse hornblende is developed in high strain regions in the southern Pottoyu Hills.|16-MAY-23
33649|Pottoyu Granite Suite|Relationships and boundaries|Overlain by c.1060 Ma felsic volcanics and Bloods Range Beds, and Neoproterozoic Dean Quartzite. Intruded by Alcurra Dyke Swarm (c. 1078 Ma) and Amata Dyke Swarm (c.800 Ma).|16-MAY-23
33649|Pottoyu Granite Suite|Age reasons|Mesoproterozoic. U-Pb zircon ages of 1144 +/- 12 Ma (25o15'3.2"S, 129o39'22.9"E) and 1192 +/- 13 Ma (25o8'12.8"S, 129o52'22.8"E), and Rb-Sr whole rock ages of 1150 Ma (25o20'49.6"S, 129o54'15.6"E; Forman, 1972) and 1190 Ma (25o24'4"S, 130o3'49.6"E; Forman, 1972).|16-MAY-23
33649|Pottoyu Granite Suite|Correlations|Similar age, but geochemically distinct from the Mantarurr and Umutju Suites and Walal Granite on Petermann Ranges.|16-MAY-23
33649|Pottoyu Granite Suite|Defn author|Edgoose C., Close D., Scrimgeour I., 1999.|16-MAY-23
33649|Pottoyu Granite Suite|Proposed publication|Petermann Ranges 1:250 000 geological mapsheet Explanatory Notes|16-MAY-23
33649|Pottoyu Granite Suite|Comments|Variably deformed and metamorphosed to amphibolite facies during the c.560 Ma Petermann Orogeny.|16-MAY-23
33649|Pottoyu Granite Suite|Defn approved by|Beier P., Kruse P.D., Young D.N.|16-MAY-23
33649|Pottoyu Granite Suite|Status|1|16-MAY-23
83005|Prentice Gneiss|Name source|Prentice Gneiss is named after Prentice Lake (GDA94, 53K, 581824mE, 7839516mN), which lies approximately 20 km to the west of the type intersection of this unit.|16-MAY-23
83005|Prentice Gneiss|Geomorphic expression|No known outcrop.|16-MAY-23
83005|Prentice Gneiss|Type section locality|Drillhole NDIBK03, down-hole depth from 281.07 m to 285.60 m. Drillhole location 599262mE 7837276mN (MGA94 zone 53) / 19.556905S 135.946267E. Drill core is stored at the NTGS core library in Alice Springs.|16-MAY-23
83005|Prentice Gneiss|Description at type locality|Medium-grained granoblastic and weakly schistose feldspathic gneiss comprising bands of feldspar and quartz, with minor biotite and white mica, along with darker bands of biotite, altered feldspar and green hornblende, with traces of pyroxene.|16-MAY-23
83005|Prentice Gneiss|Extent|Unknown.|16-MAY-23
83005|Prentice Gneiss|General description|Only known in type interval. See description above.|16-MAY-23
83005|Prentice Gneiss|Thickness range|Approximately 5.5 m apparent thickness in drill core. However, the boundaries of this unit are extremely diffuse/difficult to identify. Thickness variations are unconstrained due to insufficient data.|16-MAY-23
83005|Prentice Gneiss|Lithology|Feldspathic gneiss comprising bands of feldspar and quartz, with minor biotite and white mica, along with darker bands of biotite, altered feldspar and green hornblende, with traces of pyroxene.|16-MAY-23
83005|Prentice Gneiss|Relationships and boundaries|Difficult to determine due to deformation and high- to medium-grade metamorphism, as well as an uncertain protolith. It is uncertain whether this unit is a metamorphosed intrusive or volcanic rock. The unit is surrounded by heterogeneous pelitic gneiss and schist that is interpreted to have originated in a supracrustal setting (Alroy Formation).|16-MAY-23
83005|Prentice Gneiss|Identifying features|Felsic composition and mostly unimodal zircon population, with euhedral grains and well-defined oscillatory zoning, suggesting that the unit?s protolith was magmatic (Kositcin, Cross et al. in prep).|16-MAY-23
83005|Prentice Gneiss|Structure and Metamorphism|Weakly foliated, but metamorphic grade is medium?high. Likely partially melted/migmatitic.|16-MAY-23
83005|Prentice Gneiss|Age reasons|SHRIMP U-Pb analysis returned an igneous crystallisation age of 1870.6 +/- 3.8 Ma (Kositcin, Cross et al. in prep).|16-MAY-23
83005|Prentice Gneiss|Correlations|None known.|16-MAY-23
83005|Prentice Gneiss|Alteration and Mineralisation|None.|16-MAY-23
83005|Prentice Gneiss|Geophysical Expression|Poorly defined/unknown. Lacks distinctive geophysical properties relative to the surrounding rocks of the Alroy Formation. Difficult to distinguish in geophysical imagery due to magnetic rocks of the overlying Kalkarindji Suite.|16-MAY-23
83005|Prentice Gneiss|Defn author|A.D. Clark 24-Mar-2022.|16-MAY-23
83005|Prentice Gneiss|Proposed publication|Schofield and Clark et al., (in prep). Geology of the East Tennant area, Northern Territory, journal publication.|16-MAY-23
83005|Prentice Gneiss|References|Kositcin, N., Cross A.J., et al., in prep. Geochronology of the East Tennant area, Geoscience Australia record.|16-MAY-23
33654|Puka Granite|Name source|Puka outstation; 25o59'28.42"S, 129o53'28.42"E, PETERMANN RANGES|16-MAY-23
33654|Puka Granite|Unit history|Comprises part of the Musgrave-Mann Metamorphics of Thomson (1969) and undivided metamorphosed granites of Forman (1972).|16-MAY-23
33654|Puka Granite|Constituents|Nil. Forms part of the Umutju Granite Suite, along with the Mantapayika and Walytjatjata Granites.|16-MAY-23
33654|Puka Granite|Geomorphic expression|Low rocky hills with bouldery outcrop.|16-MAY-23
33654|Puka Granite|Type section locality|On northern side of low outcrop 5 km northwest of Puka outstation at 25o55'50.70"S, 129o53'33.46"E|16-MAY-23
33654|Puka Granite|Extent|In low outcrops immediately to the north of the Mann Ranges, Northern Territory. The extent of the unit within South Australia is unknown.|16-MAY-23
33654|Puka Granite|Thickness range|n/a|16-MAY-23
33654|Puka Granite|Thickness range|n/a|16-MAY-23
33654|Puka Granite|Lithology|Variably mylonitised, weakly porphyritic to coarsely megacrystic clinopyroxene- and hornblende-bearing granite containing plagioclase phenocrysts which mainly range in diameter from 3 mm to 3 cm but in places form megacrysts up to 9 cm. The primary hornblende granite mineralogy is overprinted by a mylonitic fabric defined by quartz, feldspar, garnet and biotite. Localised hydrous shear zones contain partial melts and hornblende-garnet bearing assemblages.  A weakly porphyritic, charnockitic granite (containing orthopyroxene and clinopyroxene) also forms part of this unit.|16-MAY-23
33654|Puka Granite|Relationships and boundaries|Interpreted to intrude 1600-1550 granulite facies felsic and mafic gneisses. The Puka Granite is intruded by 1078 Ma Alcurra Dyke Swarm and 800 Ma Amata Dyke Swarm.|16-MAY-23
33654|Puka Granite|Age reasons|Mesoproterozoic. Pb-Pb zircon evaporation age of 1145 +/- 6 Ma for weakly porphyritic hornblende granite at 25o55'50.70"S, 129o53'33.46"E.|16-MAY-23
33654|Puka Granite|Correlations|Very similar to Mantapayika and Walytjatjata Granites (also part of the Umutju Granite Suite), with only minor textural and geochemical differences.  Similar age to Pottoyu and Mantarurr Suites, PETERMANN RANGES.|16-MAY-23
33654|Puka Granite|Comments|mylonitised during the c.560 Ma Petermann Orogeny.|16-MAY-23
33654|Puka Granite|References|Thomson, B.P., 1969.  The Musgrave Block.  In Parkin, L.W. (ed.) Handbook of South Australian Geology. Geological Survey of South Australia, p.39-46. **Forman, D.J., 1972. Petermann Ranges, Northern Territory.  1:250 000 geological sheet and explanatory notes.  Bureau of Mineral Resources, Canberra, Australia.|16-MAY-23
15650|Pul Pul Rhyolite|Name source|Pul Pul Hill, latitude 13o34'S, longitude 132o35'E.|16-MAY-23
15650|Pul Pul Rhyolite|Unit history|Includes all outcrops previously referred to as the Pul Pul Rhyolite Member of the Edith River Volcanics, and outcrops of undifferentiated volcanics east and southeast (to 10 km) of Big Sunday (Stow 1:100 0000 Sheet area), Walpole & others (1968).|16-MAY-23
15650|Pul Pul Rhyolite|Type section locality|Pul Pul Hill, latitude 13o34'S, longitude 132o35'E, Stow 1:100 000 Sheet area.|16-MAY-23
15650|Pul Pul Rhyolite|Extent|Main outcrop in the South Alligator River Valley, between 10 km southeast of Big Sunday (Stow 1:100 000 Sheet area) and Rockhole mine (Mundogie 1:100 000 Sheet area). Minor scattered outcrop throughout northeastern Stow.|16-MAY-23
15650|Pul Pul Rhyolite|Thickness range|1300 m|16-MAY-23
15650|Pul Pul Rhyolite|Lithology|Siliceous altered purple and pink rhyolite and ignimbrite, rare black rhyolite and minor interbeds of siltstone and shale.|16-MAY-23
15650|Pul Pul Rhyolite|Relationships and boundaries|Major unit within the El Sherana Group. Conformably overlies the Coronation Sandstone and Scinto Breccia. Unconformably overlies metamorphosed Early Proterozoic rocks of the Pine Creek Geosyncline (1800 m.y.). Conformably overlain by the Big Sunday Formation.  Unconformably overlain by the Kombolgie Formation (1650 m.y.). Intruded by the Malone Creek Granite.|16-MAY-23
15650|Pul Pul Rhyolite|Age reasons|Late Early Proterozoic (1800-1730 m.y.), see above. (Note the Big Sunday Formation's equivalent, the Tollis Formation, is intruded by the post orogenic Cullen Granite Complex dated 1780-1730 m.y.).|16-MAY-23
15650|Pul Pul Rhyolite|Proposed publication|Geological map Commentary Mundogie 1:100 000 Sheet|16-MAY-23
79226|Puna Kura Kura Formation|Name source|Puna Kura Kura Bore in southwestern HENBURY (WALLERA 1:100 000), 132.4216degE, -24.8492degS.|16-MAY-23
79226|Puna Kura Kura Formation|Unit history|Previously mapped as undivided Winnall beds.|16-MAY-23
79226|Puna Kura Kura Formation|Constituents|Chookla Member|16-MAY-23
79226|Puna Kura Kura Formation|Geomorphic expression|Predominantly ridge-forming.|16-MAY-23
79226|Puna Kura Kura Formation|Type section locality|From 132.2989deg E,  -24.9041deg S (base) to 132.3019deg E, -24.9082deg S° (top) in the Liddle Hills, southwestern Henbury 1:250 000 sheet.|16-MAY-23
79226|Puna Kura Kura Formation|Extent|Currently mapped in central and southwestern HENBURY. Its regional extent is not yet known but it likely extends at least into LAKE AMADEUS, AYERS ROCK and BLOODS RANGE.|16-MAY-23
79226|Puna Kura Kura Formation|Thickness range|330m in type locality. Variations currently unknown.|16-MAY-23
79226|Puna Kura Kura Formation|Lithology|Comprises well-sorted and well-rounded subarkose or quartz arenite. Bedding characteristics vary up-succession suggesting changing conditions of sedimentation. Near the base the sandstone is thinly- to medium-bedded, with tabular non-tangential angular cross-beds in simple bed sets. Bedding rapidly thickens up-succession and outcrop appears massive before another rapid transition, this time to medium-bedded then predominantly thinly-bedded sandstone. These latter sandstones are planar-parallel and apparently continuously bedded suggesting that any cross-stratification is low-angle. A similar cyclicity is repeated up-succession. Weathered-out shale clasts are common in the more thinly- and medium-bedded units, particularly near the base of the formation, and are commonly associated with ripple-marks. Sandstones of the Puna Kura Kura Formation are locally trough cross-stratified. Surficial calcrete formation suggests intervals of calcareous-cemented sandstone are present, and are locally associated with interbedded fissile to flaggy, very-thinly- to thinly-bedded, micromicaeous arkose.|16-MAY-23
79226|Puna Kura Kura Formation|Depositional environment|Probably shallow marine.|16-MAY-23
79226|Puna Kura Kura Formation|Diastems or hiatuses|Not known.|16-MAY-23
79226|Puna Kura Kura Formation|Relationships and boundaries|Transitional contact with underlying Liddle Formation, locally overlain or partially incised by Chookla Member. Top not exposed in type locality. Interpreted to be the uppermost unit of Winnall Group, and is variably unconformably overlain by the Mount Currie Conglomerate, Cleland, Stairway and Carmichael sandstones, Polly Conglomerate or Langra Formation across its extent (Edgoose 2013).|16-MAY-23
79226|Puna Kura Kura Formation|Structure and Metamorphism|Folded and faulted, but apparently unmetamorphosed.|16-MAY-23
79226|Puna Kura Kura Formation|Age reasons|Probably correlates with the former Eninta Sandstone of Ranford et al (1963), that was subsequently included in Arumbera Sandstone by Warren and Shaw (1995). This suggests a late Ediacaran/early Cambrian age.|16-MAY-23
79226|Puna Kura Kura Formation|Geophysical Expression|Generally linear, low Total Magnetic Intensity typical of Winnall Group.|16-MAY-23
79226|Puna Kura Kura Formation|Defn author|N Donnellan, VJ Normington FEB-2017.|16-MAY-23
79226|Puna Kura Kura Formation|References|Edgoose CJ, 2013. Amadeus Basin. in Ahmad M and Munson TJ 'Geology and mineral resources of the Northern Territory'. Special Publication 5. ***Ranford LC, Cook PJ, Wells AT and Stewart AJ, 1963. Henbury, Northern Territory (First Edition). 1:250 000 geological map, SG 53¿01. Bureau of Mineral Resources, Australia, Canberra. ***Warren RG and Shaw RD, 1995. Hermannsburg, Northern Territory (Second Edition). 1:250 000 geological map series explanatory notes, SF 53-13. Bureau of Mineral Resources, Australia, Canberra.|16-MAY-23
15661|Pungalina Member|Name source|Pungalina Creek, in central part of Robinson River 1:250 000 sheet area (16o30'S and 137o22'E).|16-MAY-23
15661|Pungalina Member|Unit history|Not differentiated from 'Masterton Sandstone' or Hobblechain Rhyolite by Ahmad & Wygralak (1989) and Pietsch et al. (1991).|16-MAY-23
15661|Pungalina Member|Geomorphic expression|Lower unit is generally resistant, forming gently-dipping karstically-weathered mesas. Upper unit is recessive and poorly exposed.|16-MAY-23
15661|Pungalina Member|Type section locality|Around 16o30'S, 137o30'E (Robinson River sheet), adjacent to the Calvert River. The lower sandstone part of the member is best exposed at 765160E 8175260N (16o29.5'S, 137o29'E), while the upper mudstone-rich part is exposed nearby at 765130E 8172230N (16o29.5'S, 137o31'E).   REFERENCE AREAS/SECTIONS: 795120E 8099030N to 794720E 8098900N, near Redbank Mine (Calvert Hills sheet), is designated as a reference section. A conformable gradation with the upper Echo Sandstone at 792940E 8099840N is a good reference for the upper boundary. Another two useful reference sections are the drillhole intersections: (i) 680-745m in DDH Wearyan 1 drilled at 656320E 8139820N (north of Foelsche Inlier, Bauhinia Downs); and (ii) 0-88m in DD95GC007 drilled at 784810E 8163630N (Sandy Creek in northern Selby 1:100 000 sheet). Drillcore is available for inspection at the NTGS Core Library, Darwin.|16-MAY-23
15661|Pungalina Member|Extent|Exposed on the Wearyan Shelf (Plumb & Wellman, 1987), being constrained mostly to the Calvert Hills & Robinson River 1:250 000 sheet areas. It also includes a western extension into the Foelsche Inlier on Bauhinia Downs sheet.|16-MAY-23
15661|Pungalina Member|Thickness range|0-120 m.|16-MAY-23
15661|Pungalina Member|Lithology|Lower unit of pink, medium- to coarse-grained lithic sandstone with locally developed pebbly or cobbly sandstone near the base, containing abundant clasts of rhyolite, basalt and mudstone. Sandstone is cross-bedded with symmetrical to slightly asymmetrical ripples, current lineation and rare mudclasts. Local poorly stratified boulder conglomerate at the base of this member represents a talus deposit from nearby Hobblechain Rhyolite. Upper unit of red/brown dolomitic mudstone and fine-grained sandstone with halite casts, hummocky cross-stratification, load casts, tool marks and flute moulds.|16-MAY-23
15661|Pungalina Member|Depositional environment|Lower unit was deposited in a high-energy shallow water environment. Upper part was deposited in oxic restricted shallow water bodies, influenced by storm action.|16-MAY-23
15661|Pungalina Member|Relationships and boundaries|Local lateral facies variant of the lower Echo Sandstone. Conformably to unconformably overlies the Gold Creek Volcanics and sometimes the Wollogorang Formation (e.g., Camp Creek area). When unconformable, this boundary exhibits a low-angle (up to 10o) erosional truncation of the underlying units. Locally conformably overlies the Hobblechain Rhyolite, and the lower conglomeratic Pungalina Member is an epiclastic/talus apron of the rhyolite. Overlain conformably and gradationally by the upper Echo Sandstone, the contact marked by a transition from red/brown mudstone and fine-grained sandstone into white medium-grained sandstone.|16-MAY-23
15661|Pungalina Member|Age reasons|Palaeoproterozoic. Constrained by SHRIMP U-Pb zircon dates of ~1725 Ma for underlying Hobblechain Rhyolite and ~1640 Ma for the overlying middle McArthur Group (Page and Sweet, 1998).|16-MAY-23
15661|Pungalina Member|Correlations|Warramana Sandstone in the Batten Fault Zone.|16-MAY-23
15661|Pungalina Member|Defn author|David Rawlings, 1999, after Roberts et al. (1963) and Jackson et al. (1987).|16-MAY-23
15661|Pungalina Member|Comments|The Pungalina Member was initially assigned by Roberts et al. (1963) and Yates (1965) as a member of the 'Masterton Formation', which included various sedimentary and volcanic units on the Wearyan Shelf. Jackson et al. (1987) suggested that the Pungalina Member interfingered with the Gold Creek Volcanics and was overlain unconformably by the 'Masterton Sandstone' (now upper Echo Sandstone) and should therefore be a member of the Gold Creek Volcanics. The current study has shown that these relationships are incorrect and that the Pungalina Member has greater affinity with the conformably overlying upper Echo Sandstone, and should thus be returned as a member of this formation. By this definition, the Pungalina Member also includes proximal rhyolite talus conglomerate that was assigned by Ahmad & Wygralak (1989) to the Hobblechain Rhyolite.|16-MAY-23
15661|Pungalina Member|References|AHMAD M. & WYGRALAK A. S. 1989. Calvert Hills, Northern Territory; 1:250 000 Metallogenic Map Series, sheet SE53-8. Northern Territory Geological Survey Map and Explanatory Notes.   JACKSON M. J., MUIR M. D. & PLUMB K. A. 1987. Geology of the southern McArthur Basin, Northern Territory. Bureau of Mineral Resources, Australia, Bulletin 220, 173pp.   PAGE R. W. & SWEET I. P. 1998. Geochronology of basin phases in the western Mount Isa Inlier, and correlation with the McArthur Basin. Australian Journal of Earth Sciences 45, 219-232.   PIETSCH B. A., RAWLINGS D. J., CREASER P. M., KRUSE P. D., AHMAD M., FERENCZI P. A. & FINDHAMMER T. L. R. 1991. Bauhinia Downs, Northern Territory; 1:250 000 Geological Map Series, sheet SE53-3. Northern Territory Geological Survey, Map and Explanatory Notes.   PLUMB K. A. & WELLMAN P. 1987. McArthur Basin, Northern Territory; mapping of deep troughs using gravity and magnetic anomalies. BMR Journal of Australian Geology and Geophysics 10, 243-251.   ROBERTS H. G., RHODES J. M. & YATES K. R. 1963. Calvert Hills, N.T.; 1:250,000 geological series, sheet SE53-8. Bureau of Mineral Resources, Geology and Geophysics, Map and Explanatory Notes.   YATES K. R. 1965. Robinson River, N.T.; 1:250,000 geological series, sheet SE53-4. Bureau of Mineral Resources, Geology and Geophysics, Map and Explanatory Notes.|16-MAY-23
33811|Puntitjata Rhyolite|Name source|Puntitjata Outstation, north-central Hull 1:100 000 mapsheet.|16-MAY-23
33811|Puntitjata Rhyolite|Unit history|Previously described as unnamed quartz feldspar porphyry (Forman 1966).|16-MAY-23
33811|Puntitjata Rhyolite|Constituents|Nil|16-MAY-23
33811|Puntitjata Rhyolite|Geomorphic expression|Footslopes below scarp slopes, rare low rises in plains.|16-MAY-23
33811|Puntitjata Rhyolite|Type section locality|11 km west of Mount Harris at location 24o38' 32.24" S, 129o 24' 13.16" E (WGS 84).|16-MAY-23
33811|Puntitjata Rhyolite|Extent|Scattered exposures across central Hull 1:100 000 mapsheet and central western Bloods Range 1:100 000 mapsheet.|16-MAY-23
33811|Puntitjata Rhyolite|Thickness range|n/a|16-MAY-23
33811|Puntitjata Rhyolite|Lithology|Rhyolite, tuff, minor volcaniclastics.|16-MAY-23
33811|Puntitjata Rhyolite|Depositional environment|Volcanic.|16-MAY-23
33811|Puntitjata Rhyolite|Relationships and boundaries|Interpreted to overlie Mount Harris Basalt. Overlain by Bloods Range Formation or Kulail Sandstone.|16-MAY-23
33811|Puntitjata Rhyolite|Age reasons|Mesoproterozoic. Pb-Pb evaporation dating of zircon yielded an age of 1075 +/- 2 Ma (Close et al, 2002).|16-MAY-23
33811|Puntitjata Rhyolite|Correlations|Correlated with the Smoke Hill Felsic Volcanics of the Tollu Group in the western Musgrave Block, dated at 1078 +/- 5 Ma (Sun et al, 1996).|16-MAY-23
33811|Puntitjata Rhyolite|Proposed publication|Close, D.F., Edgoose, C.J., Scrimgeour, I.R., 2002. Bloods Range and Hull 1:100 000 geological special, Northern Territory Geological Survey, Explanatory notes.|16-MAY-23
33811|Puntitjata Rhyolite|References|Close, D.F., Edgoose, C.J. and Scrimgeour, I.R., 2002. Bloods Range and Hull 1:100 000 geological special, Northern Territory Geological Survey, Explanatory notes. **98/29502 - Forman, D.J., 1966. Bloods Range Northern Territory 1:250 000 geological series explanatory notes. Sheet (SG53-3). Bureau of Mineral Resources, Australia. **97/28568 - Sun, S-S., Sheraton, J.W., Glickson, A.Y. & Stewart, A.J. A major magmatic event during 1050-1080 in central Australia and an emplacement age for the Giles Complex. AGSO Research Newsletter, 24, 13-15.|16-MAY-23
41850|Putardi Quartzite|Name source|Mount Putardi 23o 28' 00" S, 131o 06' 00" E, MOUNT LIEBIG|16-MAY-23
41850|Putardi Quartzite|Unit history|Previously included within unnamed quartzite of the Arunta Complex  (Ranford 1969)|16-MAY-23
41850|Putardi Quartzite|Geomorphic expression|Prominent rounded ridges.|16-MAY-23
41850|Putardi Quartzite|Type section locality|Adjacent to Mount Liebig-Browns Bore track at 23o 26' 10.25" S, 131o 13' 06.88" E (WGS 84), MOUNT LIEBIG.|16-MAY-23
41850|Putardi Quartzite|Description at type locality|Crystalline kyanite-bearing quartzite|16-MAY-23
41850|Putardi Quartzite|Extent|Prominent east-trending ridges including Mount Peculiar, Mount Putardi, Mount Udor and Mount Udor West, extending over a strike length of ~50 km through central to western MOUNT LIEBIG|16-MAY-23
41850|Putardi Quartzite|Thickness range|Unknown, but likely to be greater than 250 metres.|16-MAY-23
41850|Putardi Quartzite|Lithology|Coarsely crystalline quartzite, commonly kyanite-bearing. Lesser quartz-muscovite schist, biotite-muscovite-quartz schist and phyllite.|16-MAY-23
41850|Putardi Quartzite|Depositional environment|Probable shallow marine environment|16-MAY-23
41850|Putardi Quartzite|Relationships and boundaries|Interpreted to overlie 1663 Ma Udor Granite and unnamed biotite granites. Unconformably overlain by Heavitree Quartzite. Intruded by 1080 Ma Stuart Pass Dolerite (Warren and Shaw 1995).|16-MAY-23
41850|Putardi Quartzite|Age reasons|late Palaeoproterozoic. Youngest population of detrital zircons has a SHRIMP U-Pb age of 1766 +/- 4 Ma (Cross et al in prep), but the unit is interpreted to overlie the Udor Granite which has a SHRIMP U-Pb zircon age of 1663 +/- 4 Ma (Cross et al in prep). Deformed during Chewings Orogeny at 1590-1560 Ma.|16-MAY-23
41850|Putardi Quartzite|Comments|The unit has undergone middle to lower amphibolite facies metamorphism. Highly deformed and is locally interleaved with Udor Granite during south-directed deformation in 1590-1560 Ma Chewings Orogeny.|16-MAY-23
41850|Putardi Quartzite|References|Cross A, Claoue-Long J, Scrimgeour IR, Close DF & Edgoose CJ, in prep. NTGS-GA Geochronology project, Report 6. Northern Territory Geological Survey, Record **Ranford LC, 1969. Mount Liebig, Northern Territory (First Edition). 1:250 000 geological map series explanatory notes, SF52-16. Bureau of Mineral Resources, Australia. **Scrimgeour IR, Close DF & Edgoose CJ, in prep. Mount Liebig, Northern Territory (Second Edition) 1:250 000 geological map series explanatory notes, SE 52-16. Northern Territory Geological Survey, Darwin. **Warren RG and Shaw RD 1995. Hermannsburg, Northern Territory (Second Edition). 1:250 000 geological map series explanatory notes, SF-53-13. Northern Territory Geological Survey, Darwin.|16-MAY-23
83014|Quart Pot Granite|Name source|The Quart Pot Granite is named after Quart Pot Dam (GDA94, 53K, 621904mE, 7848735mN), which lies approximately 15 km to the northeast of the type intersection of this unit.|16-MAY-23
83014|Quart Pot Granite|Geomorphic expression|No known outcrops.|16-MAY-23
83014|Quart Pot Granite|Type section locality|Drillhole NDIBK09, down-hole depth from 166.91 m to 168.28 m. Drillhole location 608328 mE 7843609 mN (MGA94 zone 53) / 19.499208S 136.032320E. Drill core is stored at the NTGS core library in Alice Springs.|16-MAY-23
83014|Quart Pot Granite|Description at type locality|Medium- to coarse-grained feldspar-porphyritic biotite-hornblende granite, comprising plagioclase, potassium feldspar, quartz, biotite, hornblende and muscovite, with traces of zircon, apatite, tourmaline and titanite.|16-MAY-23
83014|Quart Pot Granite|Extent|Poorly defined/unknown. A lack of distinctive geophysical properties relative to the surrounding rocks, together with complexities due to overlying magnetic rocks of the Kalkarindji Suite, result in a unit that is extremely difficult to map undercover.|16-MAY-23
83014|Quart Pot Granite|General description|This unit is only known from drillhole NDIBK09, where it is intersected numerous times. These intersections do not differ significantly in appearance from the type intersection described above.|16-MAY-23
83014|Quart Pot Granite|Thickness range|Approximately 1.5 m (maximum thickness) in the type intersection. However, the unit is intersected numerous times in drill core NDIBK09, with thickness varying between approximately 20 centimetres and three metres. The Quart Pot Granite intrudes the Francis Dam Granite over a total depth interval of approximately 140 metres, from a down-hole depth of ca. 135 m to 275 m.|16-MAY-23
83014|Quart Pot Granite|Lithology|Feldspar-porphyritic biotite-hornblende granite comprising plagioclase, potassium feldspar, quartz, biotite, hornblende and muscovite, with traces of zircon, apatite, tourmaline and titanite.|16-MAY-23
83014|Quart Pot Granite|Relationships and boundaries|The upper boundary of the type-intersection of this unit is a sharp, planar intrusive contact where the Quart Pot Granite intrudes the Francis Dam Granodiorite. The lower boundary consists of a thin pegmatitic vein separating this unit from the Francis Dam Granodiorite. The boundaries of the other intervals of the Quart Pot Granite with the Francis Dam Granodiorite in drill core NDIBK09 are also sharp and planar, and are oriented at a moderate to high angle to the core axis, suggesting that the unit was emplaced within the Francis Dam Granodiorite as a series of dykes.|16-MAY-23
83014|Quart Pot Granite|Identifying features|More porphyritic and younger than the Francis Dam Granodiorite, which it intrudes in the type intersection.|16-MAY-23
83014|Quart Pot Granite|Structure and Metamorphism|In thin-sections of the limited drill core available, the rock appears largely undeformed. In drill core, the unit is unfoliated to weakly foliated. Whether this reflects magmatic or solid-state deformation is uncertain.|16-MAY-23
83014|Quart Pot Granite|Correlations|None known, although unnamed porphyritic felsic intrusive rocks younger than ca. 1870 Ma were also intersected in drillhole DDH004, approximately 30 km to the south (Cross et al., 2020; Collings, 2009).|16-MAY-23
83014|Quart Pot Granite|Alteration and Mineralisation|Red intervals in drill core may reflect localised hematitic alteration.|16-MAY-23
83014|Quart Pot Granite|Geophysical Expression|Poorly defined/unknown.|16-MAY-23
83014|Quart Pot Granite|Geochemistry|Based on limited data, the Quart Pot Granite has a restricted, felsic compositional range (SiO2 = 69.4?73.2 wt.%). It is high-K (K2O >3.96 wt.%), peraluminous (ASI = 1.13?1.37), and has chondrite-normalised rare earth element patterns with enrichment in light rare earth elements relative to medium and heavy rare earth elements (normalised La/Yb = 19?30) with relatively flat medium to heavy rare earth elements (normalised Gd/Yb = 1.8?2.2), and a negative Eu anomaly (Eu/Eu* = 0.46?0.66). The Quart Pot Granite is compositionally similar to the Mount Lamb Suite.|16-MAY-23
83014|Quart Pot Granite|Defn author|A.D.Clark 24-MAR-2022|16-MAY-23
83014|Quart Pot Granite|Proposed publication|Schofield and Clark et al., (in prep). Geology of the East Tennant area, Northern Territory, journal publication.|16-MAY-23
83014|Quart Pot Granite|Comments|Geochemical characteristics and presence of hornblende suggest an I-type affinity, although this is somewhat at odds with peraluminous bulk rock composition.|16-MAY-23
83014|Quart Pot Granite|References|Kositcin, N., Cross A.J., et al., in prep. Geochronology of the East Tennant area, Geoscience Australia record.  **Collings, P.S., 2009. Relinquishment report for EL 23726, for the period 1 August 2003 to 31 July 2009, 801 Project. Open File Company Report, CR2009-0749. https://geoscience.nt.gov.au/gemis/ntgsjspui/handle/1/75417.  **Cross, A.J., Clark, A.D., Schofield, A., Kositcin, N., 2020. New SHRIMP U-Pb zircon and monazite geochronology of the East Tennant region: a possible undercover extension of the Warramunga Province, Tennant Creek. In: Czarnota, K., Roach, I., Abbott, S., Haynes, M., Kositcin, N., Ray, A., Slatter, E. (Eds.), Exploring for the Future: Extended Abstracts, Geoscience Australia, Canberra, 1?4. http://dx.doi.org/10.11636/132771|16-MAY-23
84112|Racecourse Formation|Name source|Unit name derived from Flemington Racecourse Claypan, which is located at approximately (GDA94) 18°23’09”S 137°03’30”E in the central MOUNT DRUMMOND 1:250 000 mapsheet area, Northern Territory.|
84112|Racecourse Formation|Unit history|Outcrops of this unit were originally mapped as either the “Mullera Formation” or the “Mittiebah Sandstone” on the First Edition MOUNT DRUMMOND 1:250 000 mapsheet (Smith and Roberts, 1963a, b) and subsequently remapped as part of the “Crow Formation” on the Second Edition MOUNT DRUMMOND 1:250 000 mapsheet (Rawlings et al 2008). The Racecourse Formation replaces Crow Formation NW of Michiebo Fault.|
84112|Racecourse Formation|Geomorphic expression|Predominantly recessive, with variably light to dark phototones in aerial imagery.|
84112|Racecourse Formation|Type section locality|There is no type locality nominated for this formation. A reference area is nominated in the western MOUNT DRUMMOND 1:250 000 mapsheet, in the vicinity of (GDA94) 18°23’S 136°45’E (53K 84878mE 66513mN).|
84112|Racecourse Formation|Extent|Unit outcrops across much of the western MOUNT DRUMMOND 1:250 000 mapsheet, Northern Territory [NW of the Michiebo Fault].|
84112|Racecourse Formation|Thickness range|Gross estimate of unit thickness, based on description of former Crow Formation (due to poor outcrop exposure and rare dip measurements), thought to reach up to approximately 2500 m (Rawlings et al, 2008).|
84112|Racecourse Formation|Lithology|Gum Waterhole Member (formerly part of the Tobacco Member of the Crow Formation): White, silicified fine- to very coarse-grained, ± pebbly, quartzose to lithic, possibly glauconitic sandstone and localised pebble-cobble conglomerate, with some minor interbedded white and flaggy shale and siltstone (Rawlings et al, 2008). Racecourse Formation (formerly part of the Crow Formation): Interbedded lithic micaceous siltstone and fine-grained sandstone, red/brown to grey shale, chalky white claystone, fine- to medium-grained quartzose to sublithic sandstone. Also, minor local red/brown, poorly sorted, feldspathic, micaceous, ferruginous and lithic, medium- to very coarse-grained sandstone, pebbly sandstone and matrix-supported conglomerate (Rawlings et al, 2008).|09-OCT-23
84112|Racecourse Formation|Depositional environment|The Racecourse Formation (formerly [part of] the Crow Formation) is interpreted as depositing across a variety of marine depositional environments, ranging from deep-shelf, through storm-dominated shelf, to very nearshore marine (Rawlings et al, 2008).|
84112|Racecourse Formation|Relationships and boundaries|The Racecourse Formation (formerly the Crow Formation) conformably overlies the Fish Hole Formation, and is unconformably overlain by the Playford Sandstone (South Nicholson Group). Gum Waterhole Member forms the top part of the formation and is conformably underlain by undivided lower Racecourse Formation.|
84112|Racecourse Formation|Identifying features|The Gum Waterhole Member of the Racecourse Formation is highly feldspathic in outcrop compared to surrounding units.|
84112|Racecourse Formation|Age reasons|Maximum depositional age derived from U-Pb SHRIMP dating of detrital zircons:  Top Lily Sandstone Member of the Playford Sandstone (stratigraphically overlies the Racecourse Formation): GA Sample 2785628 – 1546 ± 26 Ma (Kositcin and Carson, 2019). Gum Waterhole Member (formerly the Tobacco Member of the Crow Formation): GA sample 3305197 – 1591 ± 7 Ma (Kositcin et al, 2020). Racecourse Formation (formerly the Crow Formation): GA sample 2785613 – 1569 ± 22 Ma (Kositcin and Carson, 2019). Ten Mile Creek Member of the Fish Hole Formation (stratigraphically underlies the Racecourse Formation): GA Sample 2786167 – 1656 ± 12 Ma (Kositcin and Carson, 2019). Therefore, the potential depositional age range for the Racecourse Formation can be considered to extend from ca. 1591 ± 7 Ma to 1546 ± 26 Ma.|
84112|Racecourse Formation|Correlations|The Racecourse Formation, based on similar maximum depositional age estimates, can be correlated with the Lawn Hill Formation (also within the McNamara Group), and the Playford Sandstone of the South Nicholson Group (Kositcin and Carson, 2019). The Racecourse Formation may be correlative with components of the lower Favenc package (Rawlings, 1999) of the McArthur Basin.|
84112|Racecourse Formation|Alteration and Mineralisation|Unit displays mottled ferruginous and/or saprolitic weathering products.|
84112|Racecourse Formation|Geophysical Expression|Weak to moderate magnetic response, likely due to the formations in the South Nicholson Group possessing “subtle magnetic layering” (Rawlings et al, 2008).|
84112|Racecourse Formation|Defn author|Elliot Foley, Jack Simmons, Ben Williams, Charles Verdel (Northern Territory Geological Survey), Chris Carson (Geoscience Australia) 31-MAY-2023.|
84112|Racecourse Formation|Comments|Note: Standard series 1: 100 000 and 1: 250 000 mapsheet names are shown in uppercase.|
84112|Racecourse Formation|References|Carson, C. J., Kositcin, N., Anderson, J. R., and Henson, P. A. in prep. A revised Proterozoic tectono-stratigraphy of the South Nicholson region, Northern Territory, Australia - insights from SHRIMP U-Pb detrital zircon geochronology. Australian Journal of Earth Sciences. 
 **Kositcin N and Carson CJ, 2019. New SHRIMP U-Pb zircon ages from the South Nicholson and Carrara Range regions, Northern Territory. Geoscience Australia, Record 2019/09.  **Kositcin N, Carson CJ, Anderson JR, Doublier MP and Murr J, 2020. Exploring for the Future - New SHRIMP geochronology constraints on the basin evolution of the South Nicholson region. Geoscience Australia, Record 2020/025.  **Rawlings DJ, 1999. Stratigraphic resolution of a multiphase intracratonic basin system: the McArthur Basin, northern Australia. Australian Journal of Earth Sciences 46(5), 703-723.  **Rawlings DJ, Sweet IP and Kruse PD, 2008. Mount Drummond, NT (Second Edition). 1:250 000 Geological Map Series Explanatory Notes, Sheet SE 53-12. Northern Territory Geological Survey, Darwin, Northern Territory.  **Simmons JM, Williams B, Carson, C and Verdel C, 2023a. Mount Drummond, Northern Territory 1:250 000 Geological Map, Sheet SE 53-12 (Third Edition). Northern Territory Geological Survey, Darwin, Northern Territory.  **Simmons JM, Williams B, Carson, C and Verdel C, 2023b. Mount Drummond, Northern Territory 1:250 000 Geological Map Explanatory Notes, Sheet SE 53-12 (Third Edition). Northern Territory Geological Survey, Darwin, Northern Territory.  **Smith JW and Roberts HG, 1963a. Mount Drummond, NT (First Edition). 1:250 000 Geological Map Series Explanatory Notes, Sheet 53-12. Bureau of Mineral Resources, Canberra.  **Smith JW and Roberts HG, 1963b. Mount Drummond, NT (First Edition). 1:250 000 Geological Map Series, Sheet SE 53-12. Bureau of Mineral Resources, Canberra.|
27886|Ranken Limestone|Name source|From Ranken River (AVON DOWNS-RANKEN).|16-MAY-23
27886|Ranken Limestone|Unit history|Ranken limestone of Öpik (1956a, 1956b).|16-MAY-23
27886|Ranken Limestone|Geomorphic expression|Scattered bouldery outcrops on grey-black clay-rich soil.|16-MAY-23
27886|Ranken Limestone|Type section locality|Outcrop at 708543mE 7787880mN on western side of Ranken River, 6 km north of Soudan homestead (RANKEN).|16-MAY-23
27886|Ranken Limestone|Extent|Eastern flank of Alexandria-Wonarah Basement High in central Georgina Basin: northern AVON DOWNS, RANKEN, southern MOUNT DRUMMOND.|16-MAY-23
27886|Ranken Limestone|Thickness range|At least 74 m in drillhole BMR GRG 16 (RANKEN; Milligan 1963).|16-MAY-23
27886|Ranken Limestone|Lithology|Bioclast, bioclast-ooid and bioclast-intraclast rudstone, bioclast wacke/floatstone; minor calcimudstone.|16-MAY-23
27886|Ranken Limestone|Depositional environment|Marine ramp seaward of high-energy shallow subtidal barrier.|16-MAY-23
27886|Ranken Limestone|Relationships and boundaries|Conformable between Wonarah Formation below and Camooweal Dolostone above. Lenticular; passes laterally into adjacent Camooweal Dolostone. Parent unit: Barkly Group.|16-MAY-23
27886|Ranken Limestone|Age reasons|Middle Cambrian: ?Floran to late Undillan or early Boomerangian, based on poorly documented trilobite fauna (Öpik 1956b).|16-MAY-23
27886|Ranken Limestone|Correlations|Anthony Lagoon beds of Barkly Sub-basin; lower Camooweal Dolostone, Age Creek Formation, Currant Bush Limestone, V Creek Limestone, Mail Change Limestone, Devoncourt Limestone and/or Roaring Siltstone of Undilla Sub-basin; medial Arthur Creek Formation of southern Georgina Basin.|16-MAY-23
27886|Ranken Limestone|Comments|The nominated type locality supersedes the type area of Randal and Brown (1962a), which encompassed the entire then-recognised outcrop area of the formation. The new type locality is the best outcrop within this area.|16-MAY-23
70535|Redhackle Granite|Name source|After Redhackle Dam (53K 218400mE 7573000mN) in GILES.|16-MAY-23
70535|Redhackle Granite|Unit history|Mapped as unnamed Carpentarian granite Pg on First Edition MOUNT PEAKE (Offe 1978). Giles Range granite (Worden et al 2004).|16-MAY-23
70535|Redhackle Granite|Geomorphic expression|Gneissosity results in generally tabular outcrop morphology, although locally less deformed granite forms bouldery nubbins.|16-MAY-23
70535|Redhackle Granite|Type section locality|Small group of granites extending over an area of about 6 km2 centred on 222000mE 7576500mN (21o53'32"S 132o18'39"E) in GILES.|16-MAY-23
70535|Redhackle Granite|Extent|Outcrops sporadically in southwestern MOUNT PEAKE, in vicinity of Giles Range and Western Creek Yard. Minor outcrops to west-southwest and southwest of Woodalla Bore also included. Locally extends in outcrop into northwestern NAPPERBY. Airborne magnetic and regional gravity data together with company drilling indicate that the granite probably extends over an area of about 1000 km2 in southwestern MOUNT PEAKE, and a further 150 km2 in northwestern NAPPERBY. It also extends locally into southeastern MOUNT THEO.|16-MAY-23
70535|Redhackle Granite|Lithology|Grey, K-feldspar megacrystic biotite-orthogneiss or granite that includes aligned tabular, coarse equant and minor rapakivi (sensu lato) feldspar megacrystic textural variants. Rapakivi feldspars tend to be euhedral rather than classically rounded, although locally texture is more typically wiborgitic|16-MAY-23
70535|Redhackle Granite|Relationships and boundaries|Intrudes Lander Rock Formation.|16-MAY-23
70535|Redhackle Granite|Age reasons|Statherian, based on SHRIMP single-crystal zircon U-Pb igneous crystallisation age of 1772 ± 3 Ma (Worden et al 2004).|16-MAY-23
70535|Redhackle Granite|Correlations|Possibly Carrington Suite in MOUNT DOREEN (mainly YUENDUMU).|16-MAY-23
70535|Redhackle Granite|References|Offe LA, 1978. Mount Peake, Northern Territory. 1:250 000 geological series explanatory notes, SF 53-5. Bureau of Mineral Resources, Australia, Canberra.Worden KE, Claoué-Long JC, Scrimgeour IR and Lally JH, 2004. Summary of results. Joint NTGS-GA geochronology project: August 2003-December 2003. Northern Territory Geological Survey, Record 2004-004.|16-MAY-23
16061|Reynolds Range Group|Name source|Reynolds Range (5453-750320), in centre of Reynolds Range 1:100 000 Sheet area. The metasedimentary rocks forming the Reynolds Range are a conformable sequence which comprises, in ascending order, the Mount Thomas Quartzite, Pine Hill Formation, the Algamba Dolomite Member of the Pine Hill Formation,  and the Woodforde River beds, which are laterally equivalent to the Algamba Dolomite Member. The sequence is interpreted as a lithogenetic group that formed during a marine transgression.|16-MAY-23
16061|Reynolds Range Group|Proposed publication|Stratigraphic definitions in Arunta Block' - BMR Microfiche Report|16-MAY-23
16061|Reynolds Range Group|Defn Reference|80/20787|16-MAY-23
16061|Reynolds Range Group|Name first published by|Shaw R.D., Warren R.G., 1975|16-MAY-23
16061|Reynolds Range Group|Reserved? Yes/No|Yes|16-MAY-23
16104|Ringwood Member|Name source|The unit is named after Ringwood Station/Homestead (53K 495403mE 7364711mN).|16-MAY-23
16104|Ringwood Member|Unit history|The Ringwood Member was originally defined by Wells et al (1967) as a member of the Pertatataka Formation (of Prichard and Quinlan 1962). It is now a member of the Aralka Formation as defined by Preiss et al (1978). Aralka Formation also includes the Limbla Member of the Pertatataka Formation as originally defined.|16-MAY-23
16104|Ringwood Member|Geomorphic expression|Rounded hills and ridges with 'tram-line' expression of silicified, stromatolitic carbonate beds are common.|01-JUN-23
16104|Ringwood Member|Type section locality|Approximately 6.5 km southeast of Ringwood Homestead, between GDA94 53K 501638mE 7358987mN and GDA94 53K 501510 mE 7358993 mN in ILLOGWA CREEK, this is close to the inferred (but not in the stratigraphic units database) type section of Preiss et al (1978).|16-MAY-23
16104|Ringwood Member|Description at type locality|Approximately 178 m of Ringwood Member is exposed on the western limb of an anticline. Primary texture of carbonate rocks is well preserved approximately 1 km along strike to the north from this section between GDA94 53K 501370mE 7360586mN and GDA94 53K 501429mE 7360512mN. Approximately 35 m of section is intermittently exposed, interpreted to be an upward continuation of the section. Stratigraphically above this point the outcrop of the Ringwood Member is poor.  Occurrences of laterally persistent, 1-2 m thick intervals of thin- to-medium bed sets of silicified carbonate rock are present between GDA94 53K 501604mE 7358982mN and 53K 501510mE 7358993mN,  These alternate with unexposed recessive intervals containing calcrete regolith, interpreted as variably siliciclastic-bearing calcareous siltstones. This alternation of resistant and recessive units gives the 'railway line' aerial photograph expression that is characteristic of this unit (Shaw et al 1982). Bed sets on weathered surfaces are comprised of thinly-laminated siltstone alternating with thinly-bedded fine-grained calcarenite (laminites), and a variety of intraclast-bearing breccias and conglomerates. Coarse-grained intraclast breccia beds have erosional bases, with relict cross-bedding defined by the tabular intraclasts. Pebbly-intraclast breccias are formed from clasts derived from thickly-laminated/very thin-bedded siltstone units. Up section intervals of carbonate rock are less indurated and less massive. Bed thickness is typically medium (15-20 cm) and individual beds are planar and laterally persistent. Laminations within beds are also laterally persistent and define well-developed bidirectional tabular-planar, trough and ripple cross-lamination. Stratigraphically below this interval at the location GDA94 53K 501510mE 7358993mN, carbonate rock is flaggy and fissile. This location has the first occurrence of convincing, biohermal stromatolites within the local succession.|01-JUN-23
16104|Ringwood Member|Extent|The Ringwood Member is mainly exposed in southeastern ALICE SPRINGS, northwestern HALE RIVER), central-northern HALE RIVER) and southwestern ILLOGWA CREEK 1:250K mapsheets.|16-MAY-23
16104|Ringwood Member|General description|Carbonate rocks dominate the Ringwood Member. These are typically exposed in rounded hills that are surrounded by flat-lying plains which are typically formed over the recessive Aralka Formation.|16-MAY-23
16104|Ringwood Member|Thickness range|Aggregate thickness of Ringwood Member is approximately 178 m [ in type section?]. Wells et al (1967) considered the 166 m of Ringwood Member measured in the type section to be the average thickness of the unit in northwestern HALE RIVER mapsheet. The unit reaches its maximum thickness in the Limbla Syncline in south-western ILLOGWA CREEK mapsheet, where it is estimated to be in the order of 1000 m.|16-MAY-23
16104|Ringwood Member|Lithology|The Ringwood Member is largely dominated by dolostone and limestone which is stromatolitic and pisolitic in part. Beds of calcarenite and lenticular intraclast breccia dolostone are common, minor siltstone are also observed. Stromatolites are Tungussia inna and the Atilanya fennensis (Allen et al 2015) are diagnostic.|16-MAY-23
16104|Ringwood Member|Depositional environment|The Aralka Formation was deposited during the widespread flooding event that is related to the marine incursion following the deglaciation of the Sturtian glaciation (Munson et al 2013). The deposition of the siltstone, sandstone and shale units is likely to be in a low energy, shallow marine environment The deposition of the shallow water carbonate and siliciclastic members may be the result of isostatic rebound (Walter et al 1995).|16-MAY-23
16104|Ringwood Member|Fossils|The unit has two unique stromatolites, the Tungussia inna (Walter 1972), and the Atilanya fennensis (Allen et al 2015). Cryptomicrobial/stromatolitic mats are also present.|16-MAY-23
16104|Ringwood Member|Relationships and boundaries|The contact between the lower Aralka Formation and the Ringwood Member is transitional at the type section. The calcareous and dolomitic siltstone and fine-grained sandstone units of the Aralka Formation become increasingly calcareous and more thickly bedded until the siltstone is absent. In the northeast of the basin the contact is obscured by calcareous soil and aeolian sand and is often the case for the upper contact into the overlying Aralka Formation. In several locations, the Ringwood Member is a ridge or series of ridges where the overlying unit is not observed.|16-MAY-23
16104|Ringwood Member|Identifying features|The Ringwood Member is considered to be characterised by the occurrence of lenticular intraclast breccia, clast supported stromatolites. The divergently-branched Tungussia inna ('finger') (Walter 1972) stromatolite is also diagnostic.|16-MAY-23
16104|Ringwood Member|Structure and Metamorphism|The Ringwood Member has been folded and faulted in accordance with movement controlled by  being included within larger structures such as the Limbla Syncline.|16-MAY-23
16104|Ringwood Member|Age reasons|Based on stratigraphic position overlying the Sturtian glacial succession, the age of the Aralka Formation is estimated to be approximately 0.6 Ga (Edgoose 2013). This is supported by Re-Os geochronology results from samples taken within the Wallara-1 drill hole that yielded ages of 658 +/- 5 Ma (Kendall and Creaser 2004) and 657.2 +/- 5.4 Ma (Kendall et al 2006).|01-JUN-23
16104|Ringwood Member|Correlations|The Aralka Formation is correlated with the Rinkabeena Shale in the Ngalia Basin, and with part of the Inindia beds in the south-western Amadeus Basin. No direct correlations with the Ringwood Member have been made, however, the same stromatolites observed in the Ringwood Member in the northeast of the Amadeus Basin have been observed in the Inindia beds of W.A. which have been correlated with the Boord Formation (Grey et al 2012).|16-MAY-23
16104|Ringwood Member|Alteration and Mineralisation|Lead-Zinc-Silver Mineralisation: 2 unnamed occurrences in the Aralka Formation (mapped as Ringwood Member) in the Limbla Syncline, ILLOGWA CREEK 1:250K mapsheet (Edgoose 2013). Petroleum: Included in 2nd Petroleum system of Marshall et al (2007), the Aralka Formation shows good source rock potential and may be a potential unconventional petroleum source rock (Munson 2014).|01-JUN-23
16104|Ringwood Member|Defn author|VJ Normington, N Donnellan 29-OCT-2015|01-JUN-23
16104|Ringwood Member|References|Allen H-J, Grey K and Haines PW, 2015. Systematic description of Cryogenian Aralka Formation stromatolites, Amadeus Basin, Australia. Alcheringa: An Australasian Journal of Palaeontology, 1-21.   **Edgoose C, 2013. Amadeus Basin: in Ahmad M and Munson TJ (editors) 'Geology and mineral resources of the Northern Territory; Special Publication 5', Northern Territory Government.  **Grey K, Allen HJ, Hill AC and Haines PW, 2012. Neoproterozoic biostratigraphy of the Amadeus Basin 'Central Australian Basins Symposium III '. Alice Springs 
Kendall B, Creaser RA and Selby D, 2006. Re-Os geochronology of postglacial black shales in Australia: Constraints on the timing of  "Sturtian" glaciation. Geology 34, 729-732.  **Marshall TR, Dyson IA and Liu Keyu, 2007. Petroleum systems in the Amadeus Basin, central Australia: Were they oil prone?: in Munson TJ and Ambrose GJ (editors) 'Proceedings of the Central Australian Basins Symposium, Alice Springs, 16 ¿ 18th August, 2005'. Alice Springs, Northern Territory Geological Survey, Special Publication 2, 136-146.  **Munson TJ, 2014. Petroleum geology and potential of the onshore Northern Territory, 2014, Northern Territory Geological Survey, Report 22.  **Munson TJ, Kruse PD and Ahmad M, 2013. Centralian Superbasin: in Ahmad M and Munson TJ (editors) 'Geology and mineral resources of the Northern Territory; Special Publication 5', Northern Territory Government.  **Normington VJ and Donnellan N, in prep. Characterisation of the Neoproterozoic stratigraphy of the northeast Amadeus Basin, Northern Territory. Record 2015-##, Northern Territory Geological Survey.
Preiss WV, Walter MR, Coats RP and Wells AT, 1978. Lithological correlations of Adelaidean glaciogenic rocks in parts of the Amadeus, Ngalia, and Georgina basins. BMR Journal of Australian Geology and Geophysics 3, 43-53.  **Prichard CE and Quinlan T, 1962. The geology of the southern half of the Hermannsburg 1:250 000 sheet. BMR Report No. 61. Bureau of Mineral Resources Geology and Geophysics.  **Shaw R, Freeman M, Offe L and Senior B, 1982. Geology of the Illogwa Creek 1: 250 000 sheet area, central Australia: preliminary data BMR Record 1982/23, Australia.  **Walter MR, 1972. Stromatolites and the biostratigraphy of the Australian Precambrian and Cambrian. Special Publication Palaeontology 11.  **Walter MR, Veevers JJ, Calver CR and Grey K, 1995. Neoproterozoic stratigraphy of the Centralian Superbasin, Australia. Precambrian Research 73, 173-195.  **Wells AT, Ranford LC, Stewart AJ, Cook PJ and Shaw R, 1967. Geology of the north-eastern part of the Amadeus Basin, Northern Territory BMR Report 113, Australia.|01-JUN-23
16107|Rinkabeena Shale|Name source|The name of the formation is derived from Rinkabeena Bore in the eastern part of the Ngalia Basin (2130 : 4868) on the Napperby 1:250 000 sheet area (SF/53-9).|16-MAY-23
16107|Rinkabeena Shale|Type section locality|The type section of the Rinkabeena Shale is located in the headwaters of Patmungala Creek at 7387 :5334 to 73 : 5332. The type section consists predominantly of shale with some interbeds of siltstone. The formation is in places slightly calcareous especially towards its base.|16-MAY-23
16107|Rinkabeena Shale|Extent|Outcrops extend intermittently around the eastern closure of the Naburula Syncline and follow approximately the trend of the Patmungala and Gum Creeks in their headwaters. The Rinkabeena Shale is known from a shallow stratigraphic drillhole in the Davis Gap Area, and it probably occurs in the Vaughan Springs Syncline but outcrops here are extremely poor to be certain of its identification.|16-MAY-23
16107|Rinkabeena Shale|Thickness range|The Rinkabeena Shale is about 100 m thick in the type section. The shale is not sufficiently well exposed to obtain any information on regional changes in thickness.|16-MAY-23
16107|Rinkabeena Shale|Lithology|The formation consists of a very uniform sequence of green shale with subordinate interbeds of siltstone.|16-MAY-23
16107|Rinkabeena Shale|Relationships and boundaries|In the type section the Rinkabeena Shale is overlain, probably disconformably, by the Mount Davenport Diamictite Member and conformably overlies the Naburula Formation. In the Vaughan Springs Syncline it may also unconformably overlie the Albinia Formation.|16-MAY-23
16107|Rinkabeena Shale|Identifying features|Reason for Proposal of Name: A mappable unit of shale that was originally included in the basal part of the Mount Doreen Formation. It is probably separated from the Mount Davenport Diamictite Member of the Mount Doreen Formation by a disconformity.|16-MAY-23
16107|Rinkabeena Shale|Age reasons|Stratigraphic relationships and regional correlations suggest that the Rinkabeena Shale is Proterozoic in age. It is correlated with the basal part of the Pertatataka Formation (as defined by Wells et al. 1970) in the eastern part of the Amadeus Basin.|16-MAY-23
16107|Rinkabeena Shale|Defn author|Preiss W.V., Walter M.R., Coats R.P., Wells A.T., 1978|16-MAY-23
16107|Rinkabeena Shale|Proposed publication|Geology of the Ngalia Basin, Bureau of Mineral Resources, Geology & Geophysics. Bulletin|16-MAY-23
16107|Rinkabeena Shale|Defn Reference|83/24047|16-MAY-23
29328|Ritarango Formation|Name source|Ritarango Gap (latitude 12o52'S, longitude 135o36'E), a topographical saddle in the middle part of the Mitchell Range, Arnhem Bay 1:250 000 scale map sheet area.|16-MAY-23
29328|Ritarango Formation|Unit history|Comprises the upper half of the "Mitchell Range Formation" of Crohn (1954) and "Ritarango beds" of Dunnet (1965) and Plumb and Roberts (1992).|16-MAY-23
29328|Ritarango Formation|Geomorphic expression|Forms resistant and upstanding ridges, which are poorly vegetated.|16-MAY-23
29328|Ritarango Formation|Type section locality|The entire Mitchell Range was nominated as a reference area for the "Ritarango beds" by Plumb and Roberts (1992), but no boundary stratotypes were nominated. A type section for the redefined Ritarango Formation is the semi-complete north-south section through the axis of a large syncline on the eastern margin of the Mitchell Range at latitude 12o50'E, longitude 135o37'E. The base of the section is AMG NF6=40772 and the top is NF680840 (also the top boundary stratotype). The base of the formation is not exposed and consequently no lower boundary stratotype is nominated. The top boundary stratotype (NF680840) is the sinuous and scalloped contact between coarse-grained lithic sandstone of the Ritarango Formation and mildly foliated porphyritic rhyolite of the overlying Maidjunga Member (Fagan Volcanics).  Reference area: Outcrop along the Koolatong River near AMG NF600530 is representative of the formation to the south.|16-MAY-23
29328|Ritarango Formation|Extent|Small area bordering on southern Arnhem Bay and northern Blue mud Bay 1:250 000 scale map sheet areas. Along with the Dhunganda Formation, comprises the core of the Mitchell Range, centred on Ritarango Gap.|16-MAY-23
29328|Ritarango Formation|Thickness range|500-1500 m.|16-MAY-23
29328|Ritarango Formation|Lithology|Mildly deformed fine- to very coarse-grained (partly conglomeratic) lithic sandstone with minor red-brown mudstone and volcaniclastic sandstone. Sandstone is white to maroon, with local rounded to angular clasts (granules, pebbles and rarely cobbles) of mainly massive quartz, with lesser lithified sandstone, quartzite, felsic igneous (volcanic) rock and mudstone. It is medium- to very thick-bedded with large scale trough cross-bedding and rarely ripples. Rocks are commonly diffusely bedded or sheared.|16-MAY-23
29328|Ritarango Formation|Depositional environment|Based on limited palaeoenvironmental information, a shallow water fluvial setting appears the most likely depositional environment for the sandstones. Some of the finer-grained sediments may have been deposited in a floodplain or delta situation, complementary to the coarser-grained higher-energy fluvial (braided?) sediments.|16-MAY-23
29328|Ritarango Formation|Relationships and boundaries|Middle formation of the Donydji Group. Lies unconformably? on the Dhunganda Formation and conformably below the Fagan Volcanics. The lower contact was not observed, but appears to have been intruded by a major dolerite sill along much of its length. However, it clearly corresponds to a significant change in rock-types and structural characteristics, possibly related to a sedimentological break and period of tectonism. The Ritarango Formation comprises considerably coarser-grained and less-mature siliciclastic rocks with an apparently lower degree of deformation. The underlying Dhunganda Formation is made up of strongly-deformed interlayered sandstone, mudstone, volcaniclastic and bimodal igneous rocks. The boundary with the overlying Maidjunga Member of the Fagan Volcanics is conformable or "mildly" disconformable. The contact surface is often very sinuous, scalloped or crenulated in a north-south orientation on a scale of 10-100 m. This feature is most obvious on the aerial photography near the top stratotype. It is ascribed to either; a manifestation of the structural contrast between sandstones of the Ritarango Formation and porphyritic rhyolite of the Maidjunga Member, or syndepositional loading; or an irregular erosive (disconformity) surface. This problem remains unresolved. In the vicinity of NF490540 (Blue Mud Bay), the Maidjunga Member is absent (by erosion) and the Ritarango Formation is disconformably overlain by the Sheridan Member of the Fagan Volcanics.|16-MAY-23
29328|Ritarango Formation|Age reasons|Palaeoproterozoic (Statherian). The maximum age is poorly constrained by an inferred age of ~1870 Ma for the underlying Mirarrmina Complex (based on correlation with Bradshaw Complex in eastern Arnhem Bay/western Gove mapsheet areas; Plumb and Roberts, 1992). Its minimum age is constrained by 1710 Ma age determinations for concordant igneous units at the top of the Donydji Group (Rawlings and othes, in prep.). A close temporal relationship with the overlying Fagan Volcanics is favoured, suggesting it is closer in age to 1710 Ma.|16-MAY-23
29328|Ritarango Formation|Correlations|Rawlings and others (in prep.) and Rawlings (1994) suggest correlation with the upper parts of the Tawallah and Katherine River Groups in the southern and western McArthur Basin respectively. This correlation is based on geochemical, petrological, lithostratigraphic and geochronological constraints, and the physical form of igneous units.|16-MAY-23
29328|Ritarango Formation|Proposed publication|Arnhem Bay-Gove 1:250 000 Geological Map Series, Northern Territory, National Geoscience Mapping Accord, Explanatory Notes (Rawlings and others, in prep.).|16-MAY-23
29328|Ritarango Formation|Comments|The "Ritarango beds" of Dunnet (1965) and Plumb and Roberts (1965, 1992) were inadequately defined with no type section. The reference locality nominated was too broad to be useful. The need to subdivide them was brought about by the identification of significant mid-sequence changes in rock-type and structural characteristics, thought to be related to a significant sedimentological break and period of tectonism (unconformity). Most of the areas previously mapped as Ritarango beds are now mapped as Ritarango Formation, and a small mappable area of distinctly different (older) outcrop has been extracted and mapped as Dhunganda Formation.|16-MAY-23
29328|Ritarango Formation|Category|1|16-MAY-23
29328|Ritarango Formation|Defn approved by|Brakel A.T., Haines P.W.|16-MAY-23
29328|Ritarango Formation|Proposer|Rawlings D.J. 1995 (after Dunnet, 1965; Plumb and Roberts, 1992)|16-MAY-23
29328|Ritarango Formation|Reserved? Yes/No|Yes|16-MAY-23
83017|Roadhouse Formation|Name source|The Roadhouse Formation is named after the Barkly Roadhouse (GDA94, 53K, 586646mE, 7820133mN), which lies approximately 10 km to the northwest of the type intersection of this unit.|16-MAY-23
83017|Roadhouse Formation|Unit history|Rasch (2021) used the terminology Sedimentary units B through F to describe this unit.|16-MAY-23
83017|Roadhouse Formation|Geomorphic expression|No known outcrops.|16-MAY-23
83017|Roadhouse Formation|Type section locality|Drillhole NDIBK10, down-hole depth of 303 m to 724 m. Drillhole location 593827mE 7813094mN (MGA94 zone 53) / 19.775675S 135.895673E. Drill core is stored at the NTGS core library in Alice Springs.|16-MAY-23
83017|Roadhouse Formation|Description at type locality|Interbedded mudstone to coarse sandstone. Locally turbiditic. Some intervals contain interbeds of dolarenite. Base of unit defined by massive quartz arenite interbedded with conglomerate (Rasch 2021).|16-MAY-23
83017|Roadhouse Formation|Extent|This unit is associated with a regional low in gravity data and elevated conductivity in regional airborne electromagnetic data (see below). These characteristics indicate that the unit is likely to extend across an east-northeast trending, 50 km by 10 km area in the centre of the East Tennant region. Possibly continues to the west and north into the Brunette Downs Rift Corridor (e.g. Southby et al. 2021).|16-MAY-23
83017|Roadhouse Formation|General description|Only known in type interval. See description above.|16-MAY-23
83017|Roadhouse Formation|Thickness range|Approximately 421 metres in drill core, which intersects bedding at close to 90 degrees throughout, so this thickness is likely to approximate the true thickness of this unit at this location.|16-MAY-23
83017|Roadhouse Formation|Lithology|Interbedded mudstone to coarse sandstone with subordinate dolarenite, massive quartz arenite and conglomerate.|16-MAY-23
83017|Roadhouse Formation|Depositional environment|Rasch (2021) interpreted the base of the unit to have been deposited in a high-energy, shallow-water shelf environment, followed by regression towards a lower-energy, shallow-water marine setting, a transgression into a deeper-marine setting, a second regression into shallow-marine conditions, and a final transgression into a deepening marine setting towards the top of the unit.|16-MAY-23
83017|Roadhouse Formation|Fossils|Undescribed oncolites and stromatolites are present locally (Rasch, 2021).|16-MAY-23
83017|Roadhouse Formation|Relationships and boundaries|Erosional unconformity (disconformity) between this unit and overlying unnamed `unit A? (Rasch 2021). A prominent nonconformity separates this unit from underlying crystalline basement rocks of the Alroy Formation.|16-MAY-23
83017|Roadhouse Formation|Identifying features|The Roadhouse Formation is characterised by a massive quartz arenite basal unit overlain by several alternating clastic and dolarenite successions (Rasch, 2021). The formation is significantly older than unconformably overlying `unit A?, which was deposited after 902 ? 34 Ma (Rasch, 2021), and significantly younger and less deformed than underlying crystalline basement (see age section below).|16-MAY-23
83017|Roadhouse Formation|Structure and Metamorphism|Relatively flat-lying. Drill core intersection of this unit shows little evidence of significant brittle or ductile deformation.|16-MAY-23
83017|Roadhouse Formation|Age reasons|Rasch (2021) interpreted this unit to have been deposited between 1660 ? 11 Ma and 1547 ? 13 Ma, based on a detrital zircon maximum depositional age (1660 ? 11 Ma ) and a Rb-Sr age (1547 ? 13) obtained from a sample  with initial 87Sr/86Sr values and REE compositions consistent with diagenetic mineral growth in equilibrium with contemporaneous seawater.|16-MAY-23
83017|Roadhouse Formation|Correlations|Rasch (2021) used age constraints, detrital zircon spectra and geographic location to propose the Favenc package of the McArthur Basin (Rawlings, 1999) as a possible correlative of this unit.|16-MAY-23
83017|Roadhouse Formation|Alteration and Mineralisation|Rasch (2021) interpreted this unit to have undergone weak hydrothermal alteration, with carbonate and glauconite-rich beds undergoing some recrystallisation.|16-MAY-23
83017|Roadhouse Formation|Geophysical Expression|Negligible magnetic susceptibility. Appears as a subtle low in gravity data due to deeper underlying basement rocks, with consistent down-hole density readings of approximately 3 g/cc. Down-hole conductivity within the upper 100 m of unit is elevated (approximately 100 micro s) and prominent in inversions of regional airborne electromagnetic data. Lower part of the unit returned readings of ca. 50-60 micro s and is indistinguishable from basement in regional data.|16-MAY-23
83017|Roadhouse Formation|Geochemistry|Rasch (2021) presented shale geochemistry that indicates deposition in an oxic environment, becoming less oxic at around 350 m down-hole depth.|16-MAY-23
83017|Roadhouse Formation|Defn author|A. D. Clark 24-MAR-2022.|16-MAY-23
83017|Roadhouse Formation|Proposed publication|Schofield and Clark et al., (in prep). Geology of the East Tennant area, Northern Territory, journal publication.|16-MAY-23
83017|Roadhouse Formation|Comments|No constituent units, other than the informal units described by Rasch (2021) mentioned above.|16-MAY-23
83017|Roadhouse Formation|References|Rasch S., 2021. Dating and characterising a newly discovered sedimentary basin in the East Tennant region, unpublished BSc Honours thesis, University of Adelaide.  **Southby, C., Rollet, N., Carson, C., Carr, L., Henson, P., Fomin, T., Costelloe, R., Doublier, M., Close, D., 2021. The Exploring for the Future 2019 Barkly 2D Deep Crustal Reflection Seismic Survey: key discoveries and implication for resources. In Annual Geoscience Exploration Seminar (AGES) Proceedings, Alice Springs, Northern Territory.  **Rawlings D. J., 1999. Stratigraphic resolution of a multiphase intracratonic basin system: The McArthur Basin, northern Australia, Australian Journal of Earth Sciences, 46:5, 703?723.|16-MAY-23
24476|Rooneys Formation|Name source|Rooneys Yard, GR 308430, Hatches 1:100 000 Sheet area, Frew River 1:250 000 Sheet area.|16-MAY-23
24476|Rooneys Formation|Type section locality|In vicinity of Kurinelli outstation (latitude 20o37'00"S, longitude 135o02'15"E), from GR 068 180 (base, contact with intrusive gabbro) northeast to GR 030206 (top, conformable contact with overlying Kurinelli Sandstone, 1 km west of the outstation). The typical rock types of the formation are well exposed here, together with dolerite/gabbro sills (a typical association), dipping 20-35oNE.|16-MAY-23
24476|Rooneys Formation|Extent|One outcrop area in the northeast of the Davenport Province - in the northern part of Hatches and northwestern part of Hanlon 1:100 000 Sheet areas, Frew River 1:250 000 Sheet area - and one outcrop area in the southwest - in the southeastern part of Elkedra and southwestern part of George Creek 1:100 000 Sheet areas, Elkedra 1:250 000 Sheet area.|16-MAY-23
24476|Rooneys Formation|Thickness range|Uncertain because of lack of continuity of outcrop and variable dips. About 1200 m exposed in the type section.|16-MAY-23
24476|Rooneys Formation|Lithology|Recessive thin-bedded to laminated, grey or greenish grey, variably micaceous siltstone and fine-grained commonly quartz-poor arenite and greywacke. Rocks are locally cleaved, especially in the east.|16-MAY-23
24476|Rooneys Formation|Relationships and boundaries|Conformable on and locally interfingers with Epenarra Volcanics; overlain conformably by thicker bedded and more quartz-rich arenite of Kurinelli Sandstone - contact generally gradational over thickness of several metres; intruded by dolerite/gabbro sills and also by Elkedra Granite (in southeast), granophyre and unnamed granite.|16-MAY-23
24476|Rooneys Formation|Age reasons|Younger than 1870 m.y. - U-Pb zircon age of volcanics in Warramunga Group overlain unconformably by Hatches Creek Group. Older than 1640 m.y. - Rb-Sr whole-rock approximate age for Elkedra Granite intruding Rooneys Formation.|16-MAY-23
24476|Rooneys Formation|Defn author|Blake D.H., Stewart A.J., Sweet I.P., Wyche S., 1985|16-MAY-23
24476|Rooneys Formation|Proposed publication|BMR Report 257|16-MAY-23
24476|Rooneys Formation|Comments|Remarks: Part of the Ooradidgee Subgroup of the Hatches Creek Group.|16-MAY-23
24476|Rooneys Formation|Defn Reference|86/25362|16-MAY-23
24476|Rooneys Formation|Proposer|Blake D.H.|16-MAY-23
24476|Rooneys Formation|Resdate|07-OCT-1981|16-MAY-23
22777|Rorruwuy Sandstone|Name source|Rorruwuy outstation, on the northeastern coast of Arnhem Bay. (AMG PG400520, Arnhem Bay 1:250 000 scale mapsheet area).|16-MAY-23
22777|Rorruwuy Sandstone|Unit history|Previously incorrectly mapped as Mount Bonner Sandstone by Dunnet (1965).|16-MAY-23
22777|Rorruwuy Sandstone|Geomorphic expression|Northeast-striking ridge of very resistant blocky to bouldery pseudokarstic-weathered sandstone.|16-MAY-23
22777|Rorruwuy Sandstone|Type section locality|Latitude 12o11'S, longitude 136o29'15"E. Base of section is at AMG PG618528 and top is at PG615529 (Arnhem Bay mapsheet area). However, as actual contacts are not exposed, no boundary stratotypes were defined.|16-MAY-23
22777|Rorruwuy Sandstone|Extent|Outcrop is confined to a very small area 22 km northwest of Yanungbi outstation, adjacent to the Peter John River floodplain, in northeastern Arnhem Bay and northwestern Gove 1:250 000 scale mapsheet areas.|16-MAY-23
22777|Rorruwuy Sandstone|Thickness range|90 m at type section. Top and base not exposed and may be faulted. To the north and south of the type section, it appears to have been removed by the unconformity at the base of the overlying Mount Bonner Sandstone.|16-MAY-23
22777|Rorruwuy Sandstone|Lithology|White to pink, mature, silicified, fine- to medium-grained, quartzose sandstone. It is thin- to thick-bedded (mostly medium), low-angle trough cross-bedded to flat-bedded and commonly ripple marked. Mudclasts and mudclast impressions are particularly common. Some levels are pervasively pitted with iron oxides, perhaps after pyrite and/or evaporites. Pink coloured sandstone is more common in the basal part of the section, whilst white sandstone is more common in the upper part.|16-MAY-23
22777|Rorruwuy Sandstone|Depositional environment|Based on lithofacies and comparison with similar units elsewhere in the McArthur Basin, the environment of deposition is envisaged to have been shallow water, possibly represented by a fan-delta.|16-MAY-23
22777|Rorruwuy Sandstone|Relationships and boundaries|Upper sandstone formation of the Spencer Creek Group. Lies with probable disconformity on the Cato Volcanics and is probably unconformably overlain by the Mount Bonner Sandstone. The lower and upper contacts are not exposed, so these relationships are inferred. A disconformable boundary appears most likely between the Rorruwuy Sandstone and the underlying Cato Volcanics, as the sandstone is mature and basal conglomerate appears to be absent. The basal beds are also locally overturned, suggesting the contact is at least partly faulted. The overlying Mount Bonner Sandstone is inferred to be unconformable, as it exhibits a marked angular discordance with other units of the Spencer Creek Group.|16-MAY-23
22777|Rorruwuy Sandstone|Age reasons|Palaeoproterozoic (Statherian). Maximum age constrained by the underlying Cato Volcanics (~1710 Ma; Rawlings and others, in prep.). Minimum age constrained by the inferred relationship with the overlying Statherian to Calymmian Mount Bonner Sandstone. A Statherian age is favoured based on concordant relationship with rest of group and probable correlation with the Parsons Range Group, or more specifically the Fleming Sandstone?|16-MAY-23
22777|Rorruwuy Sandstone|Correlations|Probably correlates with the Parsons Range Group, but more specifically (and tentatively) the Fleming Sandstone (Blue Mud Bay and Arnhem Bay) and Kurala Sandstone (Arnhem Bay). Correlation is based on the resemblance of exposed rock-types and lithofacies.|16-MAY-23
22777|Rorruwuy Sandstone|Comments|The tentative correlations above suggest the Rorruwuy Sandstone is potentially significantly younger than the rest of the Spencer Creek Group, but is essentially concordant with the underlying stratigraphy. However, this is purely speculative and, without any conclusive evidence of a time break, there is no reason to exclude it from the group.|16-MAY-23
22777|Rorruwuy Sandstone|References|98/29079; Dunnet, D., 1965;  Rawlings, D.J. et al.|16-MAY-23
22777|Rorruwuy Sandstone|Defn approved by|Commonwealth Territories Division of the Stratigraphic Names Sub-Committee|16-MAY-23
22777|Rorruwuy Sandstone|Proposer|Rawlings, D.J.|16-MAY-23
36771|Rowley Granophyre|Name source|Rowley Range, north-central Hull 1:100 000 mapsheet.|16-MAY-23
36771|Rowley Granophyre|Unit history|Previously described as unnamed Precambrian granite (Forman 1966).|16-MAY-23
36771|Rowley Granophyre|Geomorphic expression|Low, bouldery hills.|16-MAY-23
36771|Rowley Granophyre|Type section locality|4 km west south west of Walu Outstation at 24o 44' 54.97" S, 129o 29' 22.35" E (WGS 84).|16-MAY-23
36771|Rowley Granophyre|Extent|Series of outcrops 4 km west-southwest of Walu Outstation.|16-MAY-23
36771|Rowley Granophyre|Thickness range|n/a|16-MAY-23
36771|Rowley Granophyre|Lithology|Porphyritic biotite-epidote granite with fine grained phenocrysts of feldspar.|16-MAY-23
36771|Rowley Granophyre|Depositional environment|Shallow level intrusive.|16-MAY-23
36771|Rowley Granophyre|Relationships and boundaries|Forms part of the Hull Granite Suite. Isolated outcrops, intruded by mafic dykes interpreted to belong to the ~1780 Ma Alcurra Dyke Swarm.|16-MAY-23
36771|Rowley Granophyre|Age reasons|Mesoproterozoic. Pb-Pb evaporation dating of zircon yielded an age of 1075 +/- 2 Ma (Close et al, 2002).|16-MAY-23
36771|Rowley Granophyre|Correlations|Geochemically similar to the Walu Granite (1084 +/- 9 Ma) and Imbumbunna Granite|16-MAY-23
36771|Rowley Granophyre|Proposed publication|Close, D.F., Edgoose, C.J., Scrimgeour, I.R., 2002. Bloods Range and Hull 1:100 000 geological special, Northern Territory Geological Survey, Explanatory notes.|16-MAY-23
36771|Rowley Granophyre|Comments|Granophyric texture suggests intrusion at upper crustal levels. Foliation variably developed during the 570-530 Ma Petermann Orogeny|16-MAY-23
36771|Rowley Granophyre|References|Close, D.F., Edgoose, C.J., Scrimgeour, I.R., 2002. Bloods Range and Hull 1:100 000 geological special, Northern Territory Geological Survey, Explanatory notes. **98/29502 - Forman, D.J., 1966. Bloods Range Northern Territory 1:250 000 geological series explanatory notes. Sheet (SG53-3). Bureau of Mineral Resources, Australia.|16-MAY-23
16439|Rum Jungle Complex|Name source|After Rum Jungle Creek, a NW-flowing tributary of the Finniss River.|16-MAY-23
16439|Rum Jungle Complex|Unit history|Waterhouse Complex of Johnson (1974).|16-MAY-23
16439|Rum Jungle Complex|Constituents|Igneous intrusive lithologies of the Rum Jungle Complex are informally subdivided into Ar1 15 based on geophysics and mapping. Also includes Stanley Metamorphics.|16-MAY-23
16439|Rum Jungle Complex|Extent|Exposed within two structural domes north (Rum Jungle Dome) and southwest (Waterhouse Dome) of Batchelor township in BYNOE, NOONAMAH and REYNOLDS RIVER 1:100 000 sheets.|16-MAY-23
16439|Rum Jungle Complex|Lithology|Metasediments and banded ironstone (Stanley Metamorphics), granite gneiss, migmatite, metadiorite, fine to coarse granite, porphyritic K-feldspar granite, garnetiferous granite, leucocratic granite.|16-MAY-23
16439|Rum Jungle Complex|Relationships and boundaries|Unconformably overlain by Beestons Formation sandstone and conglomerate on eastern side of domes and by Crater Formation on western side of domes. Boundary recognised as the sudden change from granite, granite-gneiss and high-grade metasediments to overlying conglomerate and arkosic sandstone. Contact is commonly intensely sheared.|16-MAY-23
16439|Rum Jungle Complex|Age reasons|2535-2525 Ma and older. SHRIMP U-Pb ages on zircons from two of the youngest granites (from intrusive relationships) from the Waterhouse and Rum Jungle domes are 2535+/-7 Ma and 2525+/-5 Ma respectively (NTGS unpublished data).|16-MAY-23
16439|Rum Jungle Complex|Correlations|Equivalent to Nanambu Complex in eastern Pine Creek Orogen.|16-MAY-23
24482|Rungutjirba Gneiss|Name source|Rungutjirba Ridge, a conspicuous west-trending ridge passing through Simpsons Gap in Alice Springs 1:100 000 Sheet area.|16-MAY-23
24482|Rungutjirba Gneiss|Type section locality|About 5 km WNW of Temple Bar Gap along a tributary of Roe Creek; Alice Springs 1:100 000 Sheet area GR 5650-670758.|16-MAY-23
24482|Rungutjirba Gneiss|Extent|Exposed south of Simpsons Gap - bifurcates westwards towards the headwaters of Laura Creek in Alice Springs 1:100 000 Sheet area.|16-MAY-23
24482|Rungutjirba Gneiss|Lithology|Fine-grained laminated quartzofeldspathic gneiss. Pink or cream in hand specimen. Commonly contains quartz or plagioclase augen less than 2 mm long.|16-MAY-23
24482|Rungutjirba Gneiss|Relationships and boundaries|Appears to intrude the Simpsons Metasediments (new name) and the Chewings Range Quartzite. Interfingering of the unit with the Burt Bluff Gneiss (new name) is interpreted to be an intrusive contact. Dolerite dykes of the Stuart Dyke Swarm (new name) intrude the Gneiss. Unconformably overlain by the Heavitree Quartzite.|16-MAY-23
24482|Rungutjirba Gneiss|Identifying features|Reason for proposed name: Distinctive unit quite different from neighbouring units.|16-MAY-23
24482|Rungutjirba Gneiss|Age reasons|Thought to be similar metamorphic age to other units of the Iwupataka Metamorphic Complex (new name) I.e. about 1620 m.y. Known to be older than the Late Proterozoic Heavitree Quartzite which unconformably overlies it and the dolerite dykes which intrude it.|16-MAY-23
24482|Rungutjirba Gneiss|Proposed publication|Geological report on the 1:100 000 scale mapping of southeastern Arunta Block, Alice Springs 1:250 000 Sheet area, Northern Territory by R.D. Shaw et al. BMR - Microfiche report in prep.|16-MAY-23
24482|Rungutjirba Gneiss|Defn Reference|80/20787|16-MAY-23
24482|Rungutjirba Gneiss|Proposer|Offe L.A.|16-MAY-23
24482|Rungutjirba Gneiss|Reserved? Yes/No|Yes|16-MAY-23
81865|Running Water Member|Name source|Running Water Yard (53K 285630mE 7307720mN in PALM VALLEY 5449 in HENBURY SG53-01).|16-MAY-23
81865|Running Water Member|Unit history|Stairway Sandstone was informally divided into lower, middle and upper units on the basis of lithology by Cook (1966 and 1972). Running Water Member is equivalent to, or is correlated with, part of the lower Stairway Sandstone. Stairway Sandstone is correlated with the Nora Formation and lowermost Carlo Sandstone of the southern Georgina Basin by Munson et al (2013).  Jakobsen et al (2013 figure 10), in contrast, interpreted that a disconformity between the Horn Valley Siltstone and the Stairway Sandstone in the Amadeus Basin may correspond with the contact between the Nora Formation and Carlo Sandstone in the Georgina Basin. The result is that Stairway Sandstone is largely correlated with the Carlo Sandstone and of Middle Darriwilian age (Jakobsen et al, 2013). However, Jakobsen et al (2013) noted that 'there is still uncertainty about the exact age and correlation of [Ordovician] formations in the three [Amadeus, Georgina and Canning] basins'.|16-MAY-23
81865|Running Water Member|Constituents|none.|16-MAY-23
81865|Running Water Member|Geomorphic expression|Ridge-forming.|16-MAY-23
81865|Running Water Member|Type section locality|28m stratigraphic thickness in the type section from 53K 290859mE 7307211mN (base) to 53K 290785mE 7307245mN (in PALM VALLEY 5449 in HENBURY SG53-01).|16-MAY-23
81865|Running Water Member|Description at type locality|Extremely pure quartz arenite (up to 95% quartz): coarsely- to very coarsely-grained, and variably well-sorted and well-rounded but with syntaxial quartz overgrowths/cement. Variably thinly to thickly bedded, but predominantly medium to thickly, and planar, parallel continuously bedded.|16-MAY-23
81865|Running Water Member|Extent|Northern HENBURY, northeastern LAKE AMADEUS and southern HERMANNSBURG 1:250,000-scale map areas in the central-northern area of the Amadeus Basin|16-MAY-23
81865|Running Water Member|Thickness range|Maintains a more-or-less consistent thickness throughout its area of outcrop.|16-MAY-23
81865|Running Water Member|Lithology|Extremely pure quartz arenite (up to 95% quartz): coarsely- to very coarsely-grained, and variably well-sorted and well-rounded but with syntaxial quartz overgrowths/cement. Variably thinly to thickly bedded, but predominantly medium to thickly, and planar, parallel continuously bedded.|16-MAY-23
81865|Running Water Member|Depositional environment|The Running Water Member includes interbedded Skolithos- and Phycodes-bearing, generally medium to thickly bedded, quartz arenite and is interpreted to have been deposited at or above storm wavebase (cf Buatois and Mangano, 2011).|16-MAY-23
81865|Running Water Member|Fossils|Phycodes is characteristic of Running Water Member, and Phycodes-bearing beds are interbedded with Skolithos-bearing beds. Minor Diplocraterion.|16-MAY-23
81865|Running Water Member|Diastems or hiatuses|Coarse grain size, and medium- to very thickly-bedded sandstone are interpreted to indicate a high-energy depositional environment, and scouring at the contacts between some beds indicates local erosional breaks.|16-MAY-23
81865|Running Water Member|Relationships and boundaries|Running Water Member is the basal unit of the Stairway Sandstone in the central-northern Amadeus Basin. It apparently conformably overlies Horn Valley Siltstone, with which it has a locally transitional contact, and is conformably overlain by the upward stratigraphic continuation of the Stairway Sandstone (the informal lower Stairway Sandstone of Cook, 1966 and 1972). Running Water Member is interpreted to be equivalent to, or a correlative of, part of the informal lower Stairway Sandstone of Cook (1966).|16-MAY-23
81865|Running Water Member|Identifying features|Medium to very thick Phycodes-bearing beds locally interbedded with Skolithos-bearing beds are diagnostic.|16-MAY-23
81865|Running Water Member|Structure and Metamorphism|Open to gentle, concentric folding; locally faulted; unmetamorphosed.|16-MAY-23
81865|Running Water Member|Age reasons|Middle Ordovician. A Middle Darriwilian age of 462.52 Ma has been reported for upper Stairway Sandstone by Kelman and Khider (2018). Conodonts and trilobites from the conformably underlying Horn Valley Siltstone indicate a late Early-Middle Ordovician age that is equivalent to the Floian-middle Dapingian international stages and the Bendigonian-Yapeenian Australian stages (Cooper, 1981; Nicoll and Jones in Kennard and Nicoll 1986; Shergold, 1986; Shergold et al, 1991; Laurie, 2006).|16-MAY-23
81865|Running Water Member|Correlations|Stairway Sandstone was informally divided into lower, middle and upper units on the basis of lithology by Cook (1966 and 1972). Running Water Member is equivalent to, or is correlated with, part of the lower Stairway Sandstone. Stairway Sandstone is correlated with the Nora Formation and lowermost Carlo Sandstone of the southern Georgina Basin by Munson et al (2013).  Jakobsen et al (2013 figure 10), in contrast, interpreted that a disconformity between the Horn Valley Siltstone and the Stairway Sandstone in the Amadeus Basin may correspond with the contact between the Nora Formation and Carlo Sandstone in the Georgina Basin. The result is that Stairway Sandstone is largely correlated with the Carlo Sandstone and of Middle Darriwilian age (Jakobsen et al, 2013). However, Jakobsen et al (2013) noted that 'there is still uncertainty about the exact age and correlation of [Ordovician] formations in the three [Amadeus, Georgina and Canning] basins'.|16-MAY-23
81865|Running Water Member|Alteration and Mineralisation|N/A|16-MAY-23
81865|Running Water Member|Geophysical Expression|Too thin to have a discrete geophysical signature|16-MAY-23
81865|Running Water Member|Geochemistry|N/A|16-MAY-23
81865|Running Water Member|Defn author|Nigel Donnellan  April 2020.|16-MAY-23
81865|Running Water Member|Proposed publication|Donnellan N et al, in prep. Henbury, Northern Territory, 1:250 000 geological map series explanatory notes, SG53-01. Northern Territory Geological Survey, Darwin.|16-MAY-23
81865|Running Water Member|Comments|Locally, eg at 53K 235383mE 7281023mN in northeastern WALLARA 5348 in HENBURY SG53-01, there is a transitional relationship between Horn Valley Siltstone and Running Water Member.|16-MAY-23
81865|Running Water Member|References|Buatois LA and Mangano MG, 2011. Ichnology: Organism-substrate interaction in space and time. Cambridge University Press, Cambridge, 358 pp.  **Cook PJ, 1966. The Stairway Sandstone-a sedimentological study. Unpublished M.Sc., thesis, Australian National University, Canberra, 214 pp.  **Cook PJ, 1972. Sedimentological studies on the Stairway Sandstone central Australia. Bureau of Mineral Resources, Australia, Bulletin 95.  **Cooper BJ, 1981. Early Ordovician conodonts from the Horn Valley Siltstone, central Australia. Palaeontology 24 (1), 147?183.  **Jakobsen KG, Nielsen AT, Harper DAT and Brock GA, 2013. Trilobites from the Middle Ordovician Stairway Sandstone, Amadeus Basin, central Australia. Alcheringa 38, 70?96.  **Kelman A and Khider K, 2018. Middle Ordovician conodonts and fish from the Stairway Sandstone, Amadeus Basin. ASEG Extended Abstracts 2018 (1), 1-1.  **Kennard JN and Nicoll RS, 1986. Late Proterozoic and early Palaeozoic depositional facies of the northern Amadeus Basin, central Australia. Sediments Down-under. 12th International Sedimentological Congress, Canberra, Australia, 24?30 August 1986. Field Excursion 25B. Bureau of Mineral Resources, Canberra.  **Laurie JR, 2006. Early Middle Cambrian trilobites from Pacific Oil and Gas Baldwin 1 well, southern Georgina Basin, Northern Territory. Memoirs of the Association of Australasian Palaeontologists 32, 127?204.  **Munson TJ, Kruse PD and Ahmad M, 2013. Centralian Superbasin; in Ahmad M and Munson TJ (compilers) `Geology and mineral resources of the Northern Territory.? Northern Territory Geological Survey, Special Publication 5.  **Shergold JH, 1986. Review of the Cambrian and Ordovician palaeontology of the Amadeus Basin, central Australia. Bureau of Mineral Resources, Australia, Report 276.  **Shergold JH, Gorter JD, Nicoll RS and Haines PW, 1991. Stratigraphy of the Pacoota Sandstone (Cambrian?Ordovician), Amadeus Basin NT. Bureau of Mineral Resources, Australia, Bulletin 237, 1?14.|16-MAY-23
41851|Russell Charnockite|Name source|Mount Russell  23o 14' 00" S, 130o 23' 00" E, MOUNT RENNIE.|16-MAY-23
41851|Russell Charnockite|Unit history|Previously included within undifferentiated gneiss, schist, amphibolite, quartzite, granite, dolerite and pegmatite of the Arunta Complex  (Ranford 1969) and undifferentiated gneissic granite of Ranford (1968).|16-MAY-23
41851|Russell Charnockite|Geomorphic expression|Prominent bouldery hills|16-MAY-23
41851|Russell Charnockite|Type section locality|Northern edge of Ehrenberg Range  23o 19' 10.47" S, 130o 22' 03.19" E, MOUNT RENNIE.|16-MAY-23
41851|Russell Charnockite|Description at type locality|Undeformed charnockite with rounded phenocrysts of zoned plagioclase 3-5 mm in diameter and pyroxene phenocrysts 1-2mm in diameter, in a fine-grained groundmass.|16-MAY-23
41851|Russell Charnockite|Extent|In hills across northeastern MOUNT RENNIE and northwestern MOUNT LIEBIG, including parts of the Ehrenberg Range and Mount Russell.|16-MAY-23
41851|Russell Charnockite|Lithology|Orthopyroxene- and clinopyroxene-bearing granite, with rounded phenocrysts of zoned plagioclase 3-5 mm in diameter and pyroxene phenocrysts 1-2mm in diameter, in a fine-grained groundmass. The rock contains abundant mafic xenoliths. In zones of higher strain, the rock is foliated and hornblende-bearing, and locally contains leucosomes.|16-MAY-23
41851|Russell Charnockite|Relationships and boundaries|Intruded by Ehrenberg Granite of Illili Suite(Close et al in prep). Intruded by dykes of Ilpilli Dolerite (Close et al in prep). Interpreted to intrude Yaya Metamorphic Complex, but no contacts are exposed.|16-MAY-23
41851|Russell Charnockite|Age reasons|late Palaeoproterozoic. Geochemically indistinguishable from the Talyi-Talyi Charnockite which has a SHRIMP U-Pb age of 1631 +/- 4 Ma (Cross et al in prep).|16-MAY-23
41851|Russell Charnockite|Correlations|Correlated with Talyi-Talyi Charnockite and Larrie Granodiorite in eastern and central MOUNT LIEBIG (Scrimgeour et al in prep). Geochemically similar to all other units of the Waluwiya Suite.|16-MAY-23
41851|Russell Charnockite|Comments|Generally undeformed, but truncated by discrete shear zones. Bodies of Russell Charnockite are interpreted to have been low-strain domains during deformation in the 1590-1560 Ma Chewings Orogeny. Metamorphosed at upper amphibolite facies.|16-MAY-23
41851|Russell Charnockite|References|Cross A, Claoue-Long J, Scrimgeour IR, Close DF & Edgoose CJ, in prep. NTGS-GA Geochronology project, Report 6. Northern Territory Geological Survey, Record 2004-003. **Close DF, Scrimgeour IR and Edgoose CJ, in prep. Mount Rennie, Northern Territory (Second Edition). 1:250 000 geological map series explanatory notes, SF52-15. Northern Territory Geological Survey, Darwin. **Ranford LC, 1968. Mount Rennie, Northern Territory (First Edition). 1:250 000 geological map series explanatory notes, SF52-15. Bureau of Mineral Resources, Australia. **Ranford LC, 1969. Mount Liebig, Northern Territory (First Edition). 1:250 000 geological map series explanatory notes, SF52-16. Bureau of Mineral Resources, Australia. **Scrimgeour IR, Close DF & Edgoose CJ, in prep. Mount Liebig, Northern Territory (Second Edition) 1:250 000 geological map series explanatory notes, SE 52-16. Northern Territory Geological Survey, Darwin. **Stewart AJ, Shaw RD, Offe LA, Langworthy AP, Warren RG, Allen AR & Clarke DB, 1980. Stratigraphic definitions of named units in the Arunta Block, Northern Territory. Bureau of Mineral Resources, Australia, Report 216.|16-MAY-23
22797|Ryans Gap Metamorphics|Name source|Ryans Gap 132o 14'E 23o 47.5'S|16-MAY-23
22797|Ryans Gap Metamorphics|Unit history|Previously mapped as unnamed metamorphic rocks of sedimentary origin (Majoribanks, 1974; Offe, 1981).|16-MAY-23
22797|Ryans Gap Metamorphics|Geomorphic expression|Low rises and rubble-covered ridges. Quartzite layers form narrow prominent ridges.|16-MAY-23
22797|Ryans Gap Metamorphics|Type section locality|(Reference localities): GR 341100 7370500 for (probable) upper unit of muscovite-bearing quartzofeldspathic gneiss, second reference locality at GR 336600 73710000 for (probable) lower unit of laminated quartzofeldspathic gneiss; both MacDonnell Ranges 1:100 000 Sheet area.|16-MAY-23
22797|Ryans Gap Metamorphics|Extent|South of the Chewings Range, west from Iwupataka to Ormiston Pound.|16-MAY-23
22797|Ryans Gap Metamorphics|Lithology|(Probable) lower unit: leucocratic laminated muscovite-bearing quartzofeldspathic gneiss, schistose quartzofeldspathic gneiss, quartzose metasediments; (probable) upper unit: muscovite-bearing schistose quartzofeldspathic gneiss, two-mica schist, biotite gneiss, micaceous metaquartzite, calc-silicate rock, para-amphibolite.|16-MAY-23
22797|Ryans Gap Metamorphics|Relationships and boundaries|Part of Iwupataka Metamorphic Complex of Offe & Shaw 1983, see also Stewart et al. 1980). Intruded by Burt Bluff Gneiss and by Cumming Meta-leucogabbro. Thought to be overlain by Chewings Range Quartzite. Cut by Stuart Dykes. Overlain by Heavitree Quartzite.|16-MAY-23
22797|Ryans Gap Metamorphics|Structure and Metamorphism|Complexly folded and metamorphosed during the Chewings Orogeny at about 1600 Ma (Teyssier et al., 1988, Collins & Shaw in press) cut by many east-west faults.|16-MAY-23
22797|Ryans Gap Metamorphics|Age reasons|Middle Proterozoic: affected by regional metamorphism at about 1590 Ma.|16-MAY-23
22797|Ryans Gap Metamorphics|Correlations|Equivalent to the Lovely Hill Schist north of the Chewings Range. Lateral facies variant of Simpsons Gap Metasediments.|16-MAY-23
22797|Ryans Gap Metamorphics|Defn author|R.D. Shaw & R.G. Warren, 21 Oct 1991.|16-MAY-23
22797|Ryans Gap Metamorphics|Comments|This 'definition' is missing the details of references mentioned in the synonymy, and shows no signs on the card of having been approved.|16-MAY-23
81827|Sainthill Suite|Name source|Mount Sainthill (135.6828degreesE 22.7469degreesS (GDA 2020)) in Jinka 1:100 000 mapsheet, Northern Territory.|16-MAY-23
81827|Sainthill Suite|Constituents|Marshall Granite; Jinka Granite.|16-MAY-23
81827|Sainthill Suite|Geomorphic expression|Generally exposed as large hills and ranges, isolated hills, nubbins, and pavement.|16-MAY-23
81827|Sainthill Suite|Type section locality|An outcrop at 135.7801degreesE 22.7642degreesS (GDA2020)  east of the Molyhil W-Mo deposit has both constituent units.|16-MAY-23
81827|Sainthill Suite|Description at type locality|m-scale dyke of Jinka Granite intrudes the Marshall Granite.|16-MAY-23
81827|Sainthill Suite|Extent|East of Little Frazer Creek and west of the Bonya Hills, south of the Dulcie Range and north of the Marshall River in HUCKITTA 1:250 000 mapsheet (Weisheit et al in prep; ~135.2529-136.0033degreesE 22.5705-22.7753degreesS (GDA2020)).|16-MAY-23
81827|Sainthill Suite|General description|Marshall Granite occurs in the western half of the extent of the Sainthill Suite; Jinka Granite in the eastern half. There is only a narrow zone west of the Elua Range where both constituent units overlap spatially.|16-MAY-23
81827|Sainthill Suite|Lithology|Jinka Granite: fine- to coarse-grained, porphyritic biotite granite. Marshall Granite: K-feldspar-plagioclase-quartz granite.|16-MAY-23
81827|Sainthill Suite|Depositional environment|Genesis: formed via melting of thickened crust during a period of crustal stabilisation and relaxation towards the end of a regional Palaeoproterozoic tectonothermal event.|16-MAY-23
81827|Sainthill Suite|Relationships and boundaries|Dyke of Jinka Granite cross-cuts Marshall Granite.|16-MAY-23
81827|Sainthill Suite|Identifying features|The Sainthill Suite comprises a variety of I-type felsic and intermediate intrusive rocks, with the two named members being the Jinka and Marshall granites. Regionally, the Marshall Granite is locally foliated to gneissic, but commonly undeformed. It is mylonitic in the Delny Shear Zone. The Jinka Granite is undeformed. Compositions of the Sainthill Suite are uniformly felsic; its constituent units are inferred to be genetically related based on mineralogical, geochemical, and structural similarities. These similarities are detailed in Beyer and Whelan (2021) and Reno et al (2022).|16-MAY-23
81827|Sainthill Suite|Structure and Metamorphism|Intrusion of the constituents of the Sainthill Suite spanned the timing of deformation on the Delny Shear Zone: the Marshall Granite ranges from undeformed to locally gneissic away from the Delny Shear Zone to foliated or locally mylonitic where it outcrops proximal to, and within the Delny Shear Zone; the Jinka Granite is undeformed. Marshall Granite is an anatectic granite that formed during regional amphibolite- to granulite-facies metamorphism. Jinka Granite formed late during that regional tectonothermal event.|16-MAY-23
81827|Sainthill Suite|Age reasons|Apatite LA?ICP?MS age of 1732 +/- 4 Ma for Marshall Granite at the Molyhil tungsten?molybdenum deposit (135.7510degreesE 22.7595degreesS (GDA 2020)) is interpreted to record timing of granite crystallisation (Reno et al 2021). SHRIMP 207Pb/206Pb zircon age of 1714 +/- 3 Ma for the Jinka Granite is interpreted as igneous crystallisation (Kositcin et al 2011).|16-MAY-23
81827|Sainthill Suite|Alteration and Mineralisation|Silicification is common in areas where the granites are intruded by quartz veins. Marshall Granite is interpreted as the driver for skarn alteration and associated W?Mo mineralisation at Molyhil W-Mo deposit and nearby prospects (McGloin and Weisheit 2021).|16-MAY-23
81827|Sainthill Suite|Geophysical Expression|Moderate-low and high responses; associated with gravity low and radiometric high responses.|16-MAY-23
81827|Sainthill Suite|Geochemistry|Monzogranite and syenogranite that are moderately metaluminous and weakly to strongly peraluminous.|16-MAY-23
81827|Sainthill Suite|Defn author|Barry Reno, Anett Weisheit, Eloise Beyer, Pablo Farias (NT Department of Industry, Tourism and Trade, Northern Territory Geological Survey) 3-MAY-2022.|16-MAY-23
81827|Sainthill Suite|References|Beyer EE and Whelan JA, 2021. Revising the igneous stratigraphy in the eastern Aileron Province: implications for geodynamic setting between ca 1.81-1.71 Ga. Annual Geoscience Exploration Seminar (AGES) Proceedings, Alice Springs, Northern Territory, 20?21 April 2021. Northern Territory Geological Survey, Darwin.  **Joklik GF, 1955. The geology and mica-fields of the Harts Range, Central Australia. Bureau of Mineral Resources, Australia, Bulletin 26.  **McGloin MV and Weisheit A, 2021. Epigenetic copper and tungsten mineralisation in JINKA and JERVOIS RANGE, northeastern Aileron Province. Northern Territory Geological Survey, Record.  **Reno BL and Fraser G, 2021. Summary of results. Joint NTGS-GA geochronology project: Constraining cooling and deformation in the eastern Aileron Province through 40Ar/39Ar step-heating of hornblende, muscovite, and biotite. Northern Territory Geological Survey, Record 2021-001.  **Reno BL, Weisheit A, Beyer EE and PG Farias, 2022. Jinka, Northern Territory. 1:100 000 geological map series explanatory notes, 6052. Northern Territory Geological Survey, Darwin.  **Shaw, R.D., Warren, R.G., Freeman, M.J., 1985. Stratigraphic definitions of named units in the Arunta Block, Northern Territory, 1979-82., Bureau of Mineral Resources, Australia, Report, 260.  **Weisheit A, Reno BL and Beyer EE, 2019. Jervois Range Special, Northern Territory (First Edition). 1:100 000 geological map series, explanatory notes 6152 and part 6252. Northern Territory Geological Survey, Darwin.  **Weisheit A et al, in prep. Huckitta, Northern Territory. 1:250 000 geological map series explanatory notes, SF53-11. Northern Territory Geological Survey, Darwin.|16-MAY-23
26131|Samarkand Pegmatite|Name source|Samarkand tungsten deposit (136.0924degreesE 22.7346degreesS (GDA2020)) in Jervois Range 1:100 000 mapsheet, Northern Territory.|16-MAY-23
26131|Samarkand Pegmatite|Unit history|First defined by Shaw et al (1985) as extensive tourmaline-muscovite-bearing pegmatitic dykes.|16-MAY-23
26131|Samarkand Pegmatite|Geomorphic expression|Low rises, bouldery hills, and nubbins.|16-MAY-23
26131|Samarkand Pegmatite|Type section locality|Samarkand tungsten deposit 136.0924degreesE 22.7346degreesS (GDA2020); access via private tracks.|16-MAY-23
26131|Samarkand Pegmatite|Description at type locality|Coarse-grained K-feldspar-quartz-muscovite-tourmaline pegmatite. Tourmaline crystals are coarse-grained and reach </=4 cm length. Muscovite is commonly green-coloured. Rare beryl. This is the only undeformed pegmatite east of the Elua Range in Jinka and Jervois Range 1:100 000 mapsheets (Weisheit et al 2019); cross-cuts all pre-existing fabrics.|16-MAY-23
26131|Samarkand Pegmatite|Extent|East of the Elua Range, south of the Johannsen and Jervois Ranges, north of the Plenty Highway in JERVOIS RANGE and JINKA 1:100 000 mapsheets.|16-MAY-23
26131|Samarkand Pegmatite|General description|Samarkand Pegmatite includes pegmatite, pegmatitic granite and leucogranite: fine- to coarse-grained to megacrystic, inequigranular to porphyritic, muscovite+/-tourmaline-bearing, rare tourmaline-quartz miaroles, local magmatic garnet; variably weathered and altered, locally brecciated; undeformed.|16-MAY-23
26131|Samarkand Pegmatite|Thickness range|Decimetre- to decametre-scale dykes; up to km-wide irregular pods.|16-MAY-23
26131|Samarkand Pegmatite|Lithology|Coarse-grained K-feldspar-quartz-muscovite-tourmaline pegmatite. Tourmaline crystals are coarse-grained and reach up to 4 cm length. Muscovite is commonly green-coloured. Rare beryl.|16-MAY-23
26131|Samarkand Pegmatite|Depositional environment|Genesis: Possibly derived from melting of a meta-sedimentary source region at the end of a regional Palaeoproterozoic tectonothermal cycle.|16-MAY-23
26131|Samarkand Pegmatite|Relationships and boundaries|Intrudes the Bonya Metamorphics, White Violet Orthogneiss, Kings Legend Metadolerite, Jericho and Thring granites. Undeformed.|16-MAY-23
26131|Samarkand Pegmatite|Identifying features|This is the only undeformed pegmatite east of the Elua Range in Jinka and Jervois Range 1:100 000 mapsheets (Weisheit et al 2019); cross-cuts all pre-existing fabrics.|16-MAY-23
26131|Samarkand Pegmatite|Structure and Metamorphism|Undeformed, unmetamorphosed.|16-MAY-23
26131|Samarkand Pegmatite|Age reasons|LA-ICP-MS apatite U-Pb lower intercept age of 1680 +/- 59 Ma is the youngest possible crystallisation age (McGloin et al 2018). Interpreted to have formed at late stages of intrusion of the nearby Marshall Granite (McGloin and Weisheit 2021).|16-MAY-23
26131|Samarkand Pegmatite|Alteration and Mineralisation|Outcrop is generally highly weathered with a jointed and dissected appearance; bleaching, silicification, and localised brecciation is common adjacent to faults and quartz veins. Tourmaline, hematite, epidote, chlorite, and/or silica alteration of host rocks adjacent to pegmatite margins is locally developed, commonly in association with extensive quartz veining. Associated with widespread epigenetic Cu-W mineralisation (McGloin and Weisheit 2021).|16-MAY-23
26131|Samarkand Pegmatite|Geophysical Expression|Patchy magnetic low response; no characteristic gravity response; strong K radiometric response.|16-MAY-23
26131|Samarkand Pegmatite|Geochemistry|Monzogranite, syenogranite, granodiorite, alkali feldspar granite. Moderately to strongly peraluminous. LREE-enriched and flat to slightly concave HREE. Depleted in Ba, Th, and U relative to Rb and K, and depleted in Nb relative to K and Ta. Deep negative Ti anomalies relative to Sm and Y.|16-MAY-23
26131|Samarkand Pegmatite|Defn author|Barry Reno, Eloise Beyer, Anett Weisheit, Pablo Farias (NT Department of Industry, Tourism and Trade, Northern Territory Geological Survey) 3-MAY-2022.|16-MAY-23
26131|Samarkand Pegmatite|References|McGloin MV and Weisheit A, 2021. Epigenetic copper and tungsten mineralisation in JINKA and JERVOIS RANGE, northeastern Aileron Province. Northern Territory Geological Survey, Record.  **McGloin MV, Whelan JA, Reno BL, Beyer EE, Weisheit A, Thompson JM, Meffre S1 and Zhukova I, 2018. Summary of results. NTGS LA-ICP-MS geochronology project: Jervois mineral field, Bonya Hills and Jinka Plain in HUCKITTA, Aileron Province, May 2014-December 2015. Northern Territory Geological Survey, Record 2018-012.  **Reno BL, Weisheit A, Beyer EE and PG Farias, 2022. Jinka, Northern Territory. 1:100 000 geological map series explanatory notes, 6052. Northern Territory Geological Survey, Darwin.  **Shaw, R.D., Warren, R.G., Freeman, M.J., 1985, Stratigraphic definitions of named units in the Arunta Block, Northern Territory, 1979-82., Bureau of Mineral Resources, Australia, Report, 260.  **Weisheit A, Reno BL and Beyer EE, 2019. Jervois Range Special, Northern Territory (First Edition). 1:100 000 geological map series, explanatory notes 6152 and part 6252. Northern Territory Geological Survey, Darwin.|16-MAY-23
72488|Sarah Granite|Name source|Lake Sarah, (GDA94) 20deg27'S, 129deg06'E, western THE GRANITES.|16-MAY-23
72488|Sarah Granite|Unit history|Informal 'Maverick granite' of industry geologists, 'Maverick monzogranite' of Smith (2000), 'Mavericks Monzogranite' of Dean (2001), `Maverick Monzogranite' of Smith (2001).|16-MAY-23
72488|Sarah Granite|Geomorphic expression|Weathered outcrops in southeastern portion of pluton, remainder covered by sand and granitoid-derived clasts; weathered zone greater than 100 m deep.|16-MAY-23
72488|Sarah Granite|Type section locality|Weathered coarse biotite granite outcrop around (GDA94) 20deg00'56''S, 129deg03'16''E. NTGS drillhole TAN99DDH2, (GDA94) 20deg01'00''S, 129deg03'15''E, THE GRANITES. Drillcore located in NTGS Core Library, Alice Springs.|16-MAY-23
72488|Sarah Granite|Extent|Discrete elongate-ovoid 7 x 4.5 km pluton in southwestern TANAMI, northwestern THE GRANITES and adjacent Western Australia.|16-MAY-23
72488|Sarah Granite|Lithology|Biotite-hornblende monzogranite and granodiorite.|16-MAY-23
72488|Sarah Granite|Relationships and boundaries|Intrudes Killi Killi Formation as outcrops on eastern margin of pluton exhibit contact metamorphic spotting after probable andalusite.|16-MAY-23
72488|Sarah Granite|Age reasons|Late Orosirian-early Statherian. SHRIMP U-Pb dating of zircon from drillhole TAN99DDH2 yielded a date of 1801 ± 4 Ma (`Maverick Monzogranite' sample of Smith 2001).|16-MAY-23
72488|Sarah Granite|Correlations|A larger (28 x 14 km), non-outcropping, magnetically discrete unnamed pluton informally known as `Pipeline Granodiorite¿ (Dean 2001) is interpreted to intrude Killi Killi Formation to north. This was also drilled by NTGS (TAN99DDH1) and yielded a date of 1802 ± 4 Ma (Cross et al 2005). It is geochemically similar to Sarah Granite and also included in Frederick Suite.|16-MAY-23
72488|Sarah Granite|Proposed publication|Crispe AJ and Vandenberg LC, in press. Geology of the Tanami Region, Northern Territory. NTGS Report.|16-MAY-23
72488|Sarah Granite|Comments|The pluton has a westnorthwesterly orientation, and is clearly delineated in magnetic imagery due to its high magnetic character relative to surrounding nonmagnetic Killi Killi Formation.|16-MAY-23
72488|Sarah Granite|References|Cross A, Claoué-Long JC, Scrimgeour IR, Crispe A and Donnellan N, 2005.Summary of results. Joint NTGS-GA geochronology project: northern Arunta and Tanami regions, 2000¿2003. Northern Territory Geological Survey, Record 2005-003.Dean AA, 2001. Igneous rocks of the Tanami Region. Northern Territory Geological Survey, Record 2001-003.Smith JB, 2000. NTGS-AGSO Geochronology Project, Report 3. Geoscience Australia, Professional Opinion 2000/27.Smith J, 2001. Summary of results. Joint NTGS-AGSO age determination program 1999-2001. Northern Territory Geological Survey, Technical Report GS2001-007.|16-MAY-23
72488|Sarah Granite|Proposer|Andrew Crispe.|16-MAY-23
16675|Scinto Breccia|Name source|The name is derived from the Scinto group of uranium projects near El Sherana.|16-MAY-23
16675|Scinto Breccia|Type section locality|The type section is that of Walpole & others (1968),for  the Scinto Breccia Member. It is at Cliff Face mine (AMG 355026) latitude 13o32'S, longitude 132o33'E where the Scinto Breccia overlies Koolpin Formation. Stow 1:100k sheet area.|16-MAY-23
16675|Scinto Breccia|Identifying features|Definition: The definition is unchanged from that of Walpole & others (1968), who described the unit as the Scinto Breccia Member of the Edith River Volcanics; but rocks of this formation have been reordered into the Edith River Group or El Sherana Group owing to the recognition of an unconformity within them (Needham & Stuart-Smith, in press). The Scinto Breccia Member has been placed in the El Sherana Group. Owing to its distinct lithology (hematitic siliceous breccia) which does not occur in any of the other units of the group, it is proposed to elevate its status to that of formation. The Scinto Breccia is developed at the base of the El Sherana Group generally adjacent to and/or above carbonate rocks in the older sequence (generally South Alligator Group). Where the Scinto Breccia is absent the base of the El Sherana Group is mostly, but not always, represented by the Coronation Sandstone and, as reported by Walpole & others, the Coronation Sandstone and Scinto Breccia can be seen to interfinger in places. The name is derived from the Scinto group of uranium projects near El Sherana. The type section is at Cliff Face mine (AMG 355026) latitude 13o32'S, longitude 132o33'E where the Scinto Breccia overlies Koolpin Formation.|16-MAY-23
16675|Scinto Breccia|Proposed publication|Needham & Stuart-Smith (in press) Australian Journal of Earth Sciences|16-MAY-23
16726|Seigal Volcanics|Name source|From Seigal Creek, a tributary of Calvert River, in southeastern Calvert Hills 1:250 000 Sheet area.|16-MAY-23
16726|Seigal Volcanics|Unit history|Unit here defined had been mapped as Peters Creek Volcanics by Carter, Brooks and Walker (1961), Roberts et al., (1963), Smith (1963), Plumb and Paine (1964) and others by correlation with type section of Carter et al., (1961) on southern side of Murphy Tectonic Ridge. Peters Creek Volcanics were therefore included in Tawallah Group. Recent detailed mapping of type section of Peters Creek Volcanics (Plumb & Sweet, in press), however, has shown that type Peters Creek Volcanics are probably equivalent to most of Tawallah Group north of Murphy Tectonic Ridge; Seigal Volcanics correlate with only the lowest of seven informal subdivisions of Peters Creek Volcanics. Peters Creek Volcanics are now confined to area south of Murphy Tectonic Ridge and are tentatively removed from Tawallah Group, pending later review of stratigraphic nomenclature of northwest Queensland when 1:100 000 mapping has progressed further.|16-MAY-23
16726|Seigal Volcanics|Type section locality|In valley 6 km northwest of confluence of Fish River and Breakneck Creek in Calvert Hills Sheet area. Base is on northern side of Lchina Wall, a prominent strike ridge of Westmoreland Conglomerate, at metric grid ref. 797319. Section extends northwards for 2 km to base of steep scarp at 795333.|16-MAY-23
16726|Seigal Volcanics|Extent|An area of about 600 km2 in northeast-trending belt in Calvert Hills and Westmoreland 1:250 000 Sheet areas on Northern Territory-Queensland border, extending 300 km to northwest as series of narrow outcrops through Bauhinia Downs and Mount Young 1:250 000 Sheet areas.|16-MAY-23
16726|Seigal Volcanics|Thickness range|From 225 m (northwest) to 1,100 m (type section).|16-MAY-23
16726|Seigal Volcanics|Lithology|Amygdaloidal basalt in flows 5-30 m thick; thin siltstone and tuffaceous interbeds in upper part. Unit includes Carolina Sandstone Member, a prominent sandstone bed which was previously defined as a member of the Peters Creek Volcanics (Roberts, Rhodes and Yates, 1963).|16-MAY-23
16726|Seigal Volcanics|Relationships and boundaries|Part of Tawallah group, which is oldest group occupying McArthur Basin. Oldest units in Group consist of thick basal conglomerate (Westmoreland Conglomerate) in Calvert Hills Sheet area and sandstone (Yiyintyi Sandstone) in Bauhinia Downs and Mount Young Sheet areas. Seigal Volcanics conformable on these basal units and overlain conformably by McDermott Formation (part of Calvert Hills area) and with apparent conformity but probable disconformity by Sly Creek Sandstone (all other areas). McDermott Fm, Sly Creek Sandstone and several younger formations (including three more volcanic units) also included in Tawallah Group. Base and top of Seigal Volcanics placed at base and top, of respectively first and last lava flows.|16-MAY-23
16726|Seigal Volcanics|Defn author|Plumb K.A., Sweet I.P., 1974.|16-MAY-23
16726|Seigal Volcanics|Proposed publication|Aus. IMM Regional Conf. Series - Mt Isa, August 1974|16-MAY-23
16726|Seigal Volcanics|Defn Reference|82/22568|16-MAY-23
16726|Seigal Volcanics|Name first published by|Rossiter A.G., 1976|16-MAY-23
38902|Settlement Creek Dolerite|Name source|Settlement Creek, which flows northeastwards from central Calvert Hills 1:250 000 map sheet, via Wollogorang Homestead (latitude 17o12'S longitude 137o57'E), into the Gulf of Carpentaria in Queensland.|16-MAY-23
38902|Settlement Creek Dolerite|Unit history|Settlement Creek Volcanics (Jackson et al 1987)|16-MAY-23
38902|Settlement Creek Dolerite|Geomorphic expression|Generally recessive with dark red/brown aerial phototones. The finer-grained upper and lower basaltic margins and adjacent hornfelsed sedimentary rocks are relatively resistant.|16-MAY-23
38902|Settlement Creek Dolerite|Type section locality|Jackson et al (1987) nominated Mallapunyah Dome as the type area. This fault bounded inlier of Tawallah Group, immediately north of Mallapunyah homestead around latitude 17o05'S longitude 135o50'E (590000E 8110000N) in north-central Wallhallow mapsheet, is reasonably accessible by 4WD vehicle, but contains some local structural complexity. The upper boundary stratotype may be found at 595400E 8110900N in the banks of Archies Creek.  REFERENCE SECTION: the interval 5-90 m in DDH HO1 in the Robinson Dome (691700E 8150700N, Robinson River mapsheet), which includes two sills divided by a hornfelsed sedimentary raft (Rawlings 2002). Drill core is stored in the NTGS Core Library, Darwin, for viewing.   REFERENCE AREAS: reference area A is at 12 Mile Creek (792000E 8091000N, Calvert Hills mapsheet), where there is a variety of upper contact relations with the Wollogorang Formation exposed over a strike length of 2 km. Reference area B is at Eagle Hawk Neck on Camp Creek (786000E 8085300N, Calvert Hills mapsheet) where there is a spectacular apophysis of dolerite within the lower Wollogorang Formation (Rod 1978, Rawlings 2002). Jackson et al (1987) nominated the northeastern end of Batten Range as a reference area, however, the recessive sedimentary outcrop in this area is now assigned to the McDermott Formation (Rawlings 2002).|16-MAY-23
38902|Settlement Creek Dolerite|Extent|Throughout the southern McArthur Basin in both the Batten Fault Zone and Wearyan Shelf, within Calvert Hills, Mount Young, Bauhinia Downs, Wallhallow and Robinson River 1:250 000 sheet areas.|16-MAY-23
38902|Settlement Creek Dolerite|Thickness range|20-200 m (Ahmad and Wygralak 1989, Rawlings 2002).|16-MAY-23
38902|Settlement Creek Dolerite|Lithology|The cores of most sheets are medium- to coarse-grained, aphyric or locally porphyritic dolerite, with ophitic and subophitic textures, comprising plagioclase, pyroxene and opaque oxides. Dolerite is incipiently altered in most areas and assumes a grey/green or pink/brown colour.  Irregular or polygonal jointing is common. The upper 1-5 m of individual sheets is generally finer-grained basalt that is weakly to moderately vesicular or vuggy. Unusual and diagnostic wrinkles and bulbous lobes (`ropy' texture) are locally recognised on the planar upper surface of the Settlement Creek Dolerite or, less commonly, as successive horizons in the upper 1 m of the dolerite sheet (Rawlings 2002). The marginal dolerite of some sheets is also strongly brecciated, with textures ranging from in situ jigsaw-fit to autoclastic and autorotated. Autorotated breccia is monomict to polymict, with angular to subrounded, vesicular and/or massive dolerite clasts.  Finely-laminated green, red/brown, yellow and purple mudstone hornfels and hornfels breccia are developed at the lower and upper contacts of the Settlement Creek Dolerite and locally as large concordant and discordant rafts within the dolerite sheets. The thickness and degree of complication of the hornfels vary according to the type of contact with the adjacent formation (ie smooth, brecciated, complex, irregular or peperitic). In some cases, hornfels is associated with polymictic (dolerite-dolostone-mudstone hornfels) autorotated breccia.|16-MAY-23
38902|Settlement Creek Dolerite|Relationships and boundaries|Lies non-conformably between hornfelsed halite-bearing mudstones of the Aquarium Formation below and Wollogorang Formation above, at essentially the same stratigraphic level of the upper Tawallah Group regionally. The upper and lower surfaces are typically smooth, planar or mildly sinuous on a 10 m scale and are generally concordant with the enclosing formations on a kilometre scale (ie sill geometry). Grossly irregular discordant contacts are recognised at several localities, and in some cases, dolerite protrusions are contiguous up into the upper Wollogorang Formation. Examples include parts of the Mallapunyah Dome, Eagle Hawk Neck and the 90 m thick dolerite intersection in DD91CCK1 at Camel Creek (805300E 8136300N, Robinson River mapsheet). The lower boundary of the Settlement Creek Dolerite is also generally planar and concordant, but in some areas (eg Mallapunyah Dome), it is a complicated amalgamation of breccias and coalescing concordant and discordant dolerite bodies. A broad laccolith geometry is interpreted for the Robinson and Mallapunyah Domes.|16-MAY-23
38902|Settlement Creek Dolerite|Age reasons|1725-1730 Ma, as constrained by the enclosing Wollogorang Formation (~1730 Ma, Jackson et al 1997) and overlying Hobblechain Rhyolite (~1725 Ma, Page and Sweet 1998).|16-MAY-23
38902|Settlement Creek Dolerite|Correlations|Intrusive correlatives include parts of the Peters Creek Volcanics (Ptp1e and Ptp6) in the Murphy Inlier (Calvert Hills and Westmoreland 1:250 000 mapsheets, Jackson et al 2000) and McCaw Formation on the western Arnhem Shelf (Mount Marumba 1:250 000 mapsheet, Sweet et al 1999). Interpreted deeper-level feeders lower in the stratigraphy include the Oenpelli Dolerite on the northern Arnhem Shelf (Millingimbi 1:250 000 mapsheet; Carson et al 1999; Kurt Kyser, Queens University, unpubl data) and altered microdolerite dykes that crosscut the Seigal Volcanics adjacent to the Murphy Inlier (Calvert Hills mapsheet, Sweet et al 1981, Rawlings 2002). Interpreted extrusive correlatives of the Settlement Creek Dolerite include the upper `flow' unit of the Gold Creek Volcanics (`Basalt 4') on the Wearyan Shelf (Calvert Hills and Robinson River mapsheets, Rawlings 2002).|16-MAY-23
38902|Settlement Creek Dolerite|Comments|This formation was originally defined as the Settlement Creek Volcanics by Jackson et al (1987), having been interpreted as a mainly extrusive volcanic formation (Yates 1963, Roberts et al 1963, Ahmad and Wygralak 1989, Jackson et al 1987, Pietsch et al 1991, Haines et al 1993). The main evidence cited was the 'ropy' upper surface, marginal volcanic breccia ('agglomerate' or autobreccia) and locally intermingled muddy and 'tuffaceous' sedimentary rocks.  However, detailed studies by Bull (1993), Rogers (1996) and Rawlings (2002) have observed that it typically has a coarse-grained doleritic texture and intrusive relationship with enclosing hornfelsed sedimentary rocks, indicating that it is a regional-scale composite set of dolerite sills. Consequently, it is renamed here the Settlement Creek Dolerite to reflect the coarser grainsize, and redefined in terms of its boundary relationships and mode of emplacement.  The distribution of the Settlement Creek Dolerite in Bauhinia Downs and Mount Young mapsheets has been corrected since the erroneous definition of Jackson et al (1987). Most sedimentary intervals that were assigned to this formation have now been remapped as McDermott Formation (Pietsch et al 1991, Haines et al 1993).|16-MAY-23
37961|Shadow Group|Name source|From Shadow Bluff, in Grant Bluff Formation in the western Elua Range, central HUCKITTA.|16-MAY-23
37961|Shadow Group|Unit history|Former component of Mopunga Group sensu Smith (1964) in part; Central Mount Stuart beds of Smith and Milligan (1964) in part; and mapped as PLuEs3 of that unit by Shaw and Warren (1975) in part; Donkey Creek beds of Walter (1980) in part; Arthur Creek beds (Smith 1964) in part; Errarra Formation of Freeman (1986) in part (Ambrose et al 2001).|16-MAY-23
37961|Shadow Group|Constituents|Octy Formation, Neutral Junction Formation, Mount Baldwin Formation, Adam Shale, Mount Birnie beds, Red Heart Dolostone; provisionally Sylvester Sandstone and Riversdale Formation.|16-MAY-23
37961|Shadow Group|Extent|BARROW CREEK, ALCOOTA, ELKEDRA, HUCKITTA, TOBERMORY, HAY RIVER, MOUNT WHELAN, GLENORMISTON, URANDANGI, DUCHESS.|16-MAY-23
37961|Shadow Group|Relationships and boundaries|Overlies Elkera Formation of Mopunga Group with angular unconformity, presumed to unconformably overlie Sun Hill Arkose of Keepera Group, and disconformably overlies Proterozoic rocks including Central Mount Stuart Formation of Mopunga Group and Little Burke Tillite of Keepera Group (Shergold 1985:7, Haines et al 1991). Unconformably (Shergold and Druce 1980) to conformably and gradationally (Shergold et al 1985) overlain by Thorntonia Limestone or where this is absent, unconformably overlain by Beetle Creek Formation, Chabalowe Formation (all Narpa Group) or Mesozoic sedimentary rocks.|16-MAY-23
37961|Shadow Group|Age reasons|Ichnofossils of Cambrian aspect in Mount Baldwin Formation, Octy Formation, Neutral Junction Formation and Mount Birnie beds, acritarchs and bioturbated beds in Adam Shale, and archaeocyaths and small skeletal fossils in Red Heart Dolostone confirm an Early Cambrian age (Nemakit-Daldynian or Tommotian to late Atdabanian in Siberian terms; Laurie and Shergold 1985, Walter et al 1989, Debrenne and Zhuravlev 1992). Sylvester Sandstone presumed by Shergold (1985:7) to be Early Cambrian by lithological correlation with Mount Baldwin Formation, but may be Neoproterozoic (Pritchard in Shergold and Druce 1980:155). Riversdale Formation is directly overlain by Thorntonia Limestone, either conformably (Shergold et al 1985) or unconformably (Shergold and Druce 1980), and is thus in the age range of late Early to early Middle Cambrian.|16-MAY-23
37961|Shadow Group|Correlations|Arumbera Sandstone III and IV, Quandong Conglomerate, Eninta Sandstone, Mount Currie Conglomerate, Mutitjulu Arkose and Todd River Dolostone of Amadeus Basin, Yuendumu Sandstone II and Walbiri Dolostone of Ngalia Basin (Shergold et al 1985, Young et al 2002).|16-MAY-23
37961|Shadow Group|Comments|The Shadow Group embraces all Lower Cambrian rocks in the southern Georgina Basin, although these do not span the entire epoch. The Sylvester Sandstone and Riversdale Formation are only provisionally included in the group due to uncertainty as to their age: the former may be older (Mopunga or even Keepera Group), the latter younger (Narpa Group). Regardless, the Shadow Group includes an unconformity between Mount Baldwin Formation-Adam Shale and Red Heart Dolostone (Shergold 1985), and possibly between Octy Formation and Neutral Junction Formation (Haines et al 1991).|16-MAY-23
29329|Sheridan Member|Name source|Sheridan Creek, a west-flowing fresh-water tributary of the Goyder River. Its headwaters cut the unit near AMG NF470500 (Blue Mud Bay 1:250 000 scale mapsheet area).|16-MAY-23
29329|Sheridan Member|Unit history|Includes all outcrop previously assigned to the now redundant "Sheridan Formation" of Plumb and Roberts (1965, 1992). Also includes some areas of previously undifferentiated Fagan Volcanics. Equates roughly to the informal "basal unit b" of Plumb and Roberts (1992).|16-MAY-23
29329|Sheridan Member|Geomorphic expression|Forms resistant banded strike ridges, seperating relatively recessive valleys of the enclosing igneous-dominated members.|16-MAY-23
29329|Sheridan Member|Type section locality|The most complete and representative sections of this unit are in the Blue Mud Bay mapsheet area, where access is restricted to helicopter. The type section follows a small un-named creek near lat. 13o07'30"s, long. 135o30'30"E. The section runs between the lower boundary stratotype at AMG NF592490 and the top boundary stratotype at NF586486, and comprises mainly sandstone and mudstone. REFERENCE AREAS: For ease of access, incomplete exposures adjacent to the Gove-Bulman road around NF680960 (Arnhem Bay mapsheet area) are nominated as a reference area. The localised sandstone-mudstone-conglomerate lithofacies recognised only in the Blue Mud Bay mapsheet area, originally the "Sheridan Formation" of Plumb and Roberts (1965), is best exposed west of the Sheridan Fault. These authors nominated a reference area near lat. 13o06's, long. 135o24'30"E. (AMG NF480510) which is retained.|16-MAY-23
29329|Sheridan Member|Extent|Outcrop occurs in two distinct areas in the northern and southern parts of the Mitchell Range, in both Arnhem Bay and Blue Mud Bay 1:250 000 scale mapsheet areas. The areas are seperated by a considerable distance (~30km).|16-MAY-23
29329|Sheridan Member|Thickness range|200-400m.|16-MAY-23
29329|Sheridan Member|Lithology|Fine- to medium-grained (locally coarse), white to maroon, thin- to thick-bedded, quartzose-lithic-feldspathic sandstones with trough cross-beds and ripples. Interbedded on 5cm to 50 m-scale with red-brown massive to poorly-bedded micaceous and sandy mudstone. locally associated with conglomeratic lithic sandstone. Clasts of mudstone, felsic igneous rock, sandstone and quartzite are common. Locally sheared.|16-MAY-23
29329|Sheridan Member|Depositional environment|Sandstone mudstone lithofacies: shallow water, low-energy setting, perhaps fan-delta. Conglomeratic lithofacies: high energy fluvial (alluvial).|16-MAY-23
29329|Sheridan Member|Relationships and boundaries|Lies conformably between the felsic igneous Maidjunga Member and the mixed igneous-sedimentary Dhupuwamirri Member. The lower boundary is gradational, with porphyritic rhyolite overlain by a maturing upward sequence of volcaniclastic sandstones. In the vicinity of NF490540 (Blue Mud Bay), The Maidjunga Member is absent (by erosion) amnd the Ritarango Formation is disconformably overlain by the conglomeratic lithofacies of the Sheridan member. This appears to be the result of localised intraformational faulting and erosion. The Upper contact is often well exposed and comprises flow-banded, partly amygdaloidal and autoclastic, porphyritic rhyolite of the Dhupuwamirri Member sitting on red-brown mudstone and white sandstone of the Sheridan Member. A locally peperitic base indicates emplacement of the igneous (probably extrusive) body onto wet unconsolidated sediment.|16-MAY-23
29329|Sheridan Member|Age reasons|Paleoproterozoic (Statherian). Well constrained by the ages of the enclosing Maidjunga and Dhupuwamirri Members, which are 1710 Ma (Rawlings and other, in prep).|16-MAY-23
29329|Sheridan Member|Correlations|Rawlings and others (in prep.) and Rawlings (1994) suggest correlation with the upper parts of the Tawallah and Katherine River Groups in the southern and western McArthur Basin respectively. More locally, it correlates with the Spencer Creek Group in the northeastern Arnhem Bay mapsheet area.|16-MAY-23
29329|Sheridan Member|Comments|The "Sheridan Formation" originally mapped by Plumb and Roberts (1965), included small outcrops of conglomeratic rocks near NF470500 (Blue Mud bay) which had poorly understood stratigraphic relationships. It was seen to unconformably overlie the Ritarango beds and Fagan Volcanics, yet be older than Parsons Range Group. A disconformable relationship with the Ritarango Formation and a conformable relationship with the Dhupuwamirri Member of the Fagan Volcanics are now established (Rawlings and others, in prep.) A broad correlation, based on facies characteristics, also exists between these conglomeratic rocks and the mudstone, sandstone sequence in the middle part of the Fagan Volcanics to the east, thus indicating the need to redefine the unit as the Sheridan Member of the Fagan Volcanics. The name Sheridan Formation is now abandoned.|16-MAY-23
29329|Sheridan Member|References|Plumb, K.A. and Roberts, H.G., 1965. Blue Mud Bay - Port Langdon, Northern Territory 1:250 000 Geological Series. Burea of Mineral Resources, Australia, Explanatory Notes, SD53-7, 8. **Plumb, K.A. and Roberts, H.G., 1992. The geology of Arnhem Land, Northern Territory, Bureau of Mineral Resources, Australia, Record, 1992/55. **Rawlings, D.J., 1994. Characterisation and correlation of volcanism in the McArthur Basin and transitional domain, N.T. Proceedings the AusIMM Annual Conference, Darwin 1994, pp. 157-160. **Rawlings, D.J. and others, in prep. Arnhem Bay - Gove, Northern Territory 1:250 000 Geological Map Series. National Geoscience Mapping Accord, Explanatory Notes, SD53 -3, 4.|16-MAY-23
24493|Shoobridge Granite|Name source|Mt Shoobridge, a conical flat-topped hill at AMG 467037, Tipperary 1:100 000.|16-MAY-23
24493|Shoobridge Granite|Unit history|Mount shoobridge granite of Jensen and others (1916); Mount Shoorbridge Granite of Sullivan and Iten (1952); Shoobridge Granite of Malone (1962), Walpole and others (1968), D'Addario and Pillinger (1985).|16-MAY-23
24493|Shoobridge Granite|Type section locality|Area about 0.3 km2 of dark medium-grained slightly porphyritic biotite-hornblende granite around AMG 463042 (latitude 13o31'10"S, longitude 131o16'30"E).|16-MAY-23
24493|Shoobridge Granite|Extent|Near-circular surface area of about 3 km2 transected by old Stuart Highway, north-central Tipperary 1:100 000 sheet area.|16-MAY-23
24493|Shoobridge Granite|Lithology|Core of leucogranite surrounded by biotite-hornblende granite, in turn enclosed by quartz monzodiorite. Quartz-tourmaline veins are associated with fault or shear zones. Mineralogy includes sodic plagioclase, alkali feldspar, biotite, hornblende, muscovite, chlorite and carbonate (at least partly as alteration product); accessory minerals: apatite, sphene, zircon, opaque minerals.|16-MAY-23
24493|Shoobridge Granite|Relationships and boundaries|Intrudes Early Proterozoic Burrell Creek Formation and possibly Mount Bonnie Formation. Hornfelsed contact aureole best exposed along eastern and southern boundaries.|16-MAY-23
24493|Shoobridge Granite|Age reasons|Early Proterozoic. No isotopic dating available.|16-MAY-23
24493|Shoobridge Granite|Proposed publication|Tipperary 1:100 000 explanatory notes. NTGS|16-MAY-23
24493|Shoobridge Granite|Comments|87/25872|16-MAY-23
24493|Shoobridge Granite|References|01/31589; GOLD1765; B012; B082.|16-MAY-23
24493|Shoobridge Granite|Proposer|Mulder C.A. (after Malone, 1962)|16-MAY-23
26139|Short Range Sandstone|Name source|Short Range in the Tennant Creek 1:250 000 Sheet area, latitude 19o12'S, longitude 134o05'30"E.|16-MAY-23
26139|Short Range Sandstone|Type section locality|Near grid reference 401894, where a southern tributary of Attack Creek cuts through the sandstone. The section, generalised, shows pink, light grey, cream and purple, massive to blocky orthoquartzite. It is silicified, compact and resistant to weathering. It is characterised in its lower half by very long, low-angle, medium to large-scale cross-beds about 1 m thick. Ripple marks are common throughout. The upper half of the formation is characterised by numerous shale clasts, abundant wave-formed ripple marks and small to medium scale cross-beds.|16-MAY-23
26139|Short Range Sandstone|Extent|In the Tennant Creek Sheet area, the formationcrops out on the western side of the Whittington Range, and a short distance north of the eastern end of the Short Range.|16-MAY-23
26139|Short Range Sandstone|Thickness range|200 to 800 m. Genrally, the formation thickens northwards.|16-MAY-23
26139|Short Range Sandstone|Relationships and boundaries|Conformably overlies the Morphett Creek Formation and is conformably overlain by the Attack Creek Formation.|16-MAY-23
26139|Short Range Sandstone|Age reasons|By assumed correlation of Tomkinson Creek Beds with Hatches Creek Group, late Early Proterozoic to Early Carpentarian.|16-MAY-23
26139|Short Range Sandstone|Proposed publication|See references under Mendum and Tonkin; Dodson and Gardener.|16-MAY-23
26139|Short Range Sandstone|Name first published by|Stewart A.J., Langworthy A.P., Warren R.G., Offe L.A., Glikson A.Y., Wells A.T., Le Messurier P., Gardener J.E.F., 1976|16-MAY-23
24495|Simpsons Gap Metasediments|Name source|Simpsons Gap 17 km west of Alice Springs in the Alice Springs 1:100 000 Sheet area. NB: National Mapping had for some time referred to the gap as Simpson Gap. However their policy has changed and the possessive 's' has been added - thus Simpsons Gap.|16-MAY-23
24495|Simpsons Gap Metasediments|Type section locality|Along Jay Creek in Alice Springs 1:100 0000 Sheet area between GR 5650-506767 to 513779. Basal conglomerate does not crop out at type locality but a good exposure can be seen at GR 5650-765782 in Alice Springs 1:100 000 Sheet area.|16-MAY-23
24495|Simpsons Gap Metasediments|Extent|South of Simpsons Gap and between the Chewings Range and the Burt Bluff Gneiss (new name) in Alice Springs 1:100 000 Sheet area. The unit is also correlated with rocks which crop out south of the Chewings Range in MacDonnell Ranges and Hermannsburg 1:100 000 Sheet areas to the west.|16-MAY-23
24495|Simpsons Gap Metasediments|Lithology|Thin cobble conglomerate at base, overlain by recrystallised micaceous and feldspathic quartz sandstone with interlayered staurolite-garnet-two mica schist and a small amount of amphibolite. Some interlayered white, grey and blue recrystallised quartzite.|16-MAY-23
24495|Simpsons Gap Metasediments|Relationships and boundaries|East of Simpsons Gap the Metasediments overlie nonconformably the Sadadeen Range gneiss (new name); to the south they are unconformably overlain by the Heavitree Quartzite. Concordantly overlain to the north by the Chewings Range Quartzite (defined). Metasediments are intruded by both the Burt Bluff Gneiss and Rungutjirba Gneiss (new name). Dolerite dykes of the Stuart Dyke Swarm (new name) intrude the Metasediments.|16-MAY-23
24495|Simpsons Gap Metasediments|Identifying features|Reason for proposed name: This unit forms a discrete mass of mainly metasedimentary origin which non conformably overlies older crystalline basement.|16-MAY-23
24495|Simpsons Gap Metasediments|Age reasons|No direct evidence. Older than unconformably overlying Late Proterozoic Heavitree Quartzite and intrusive Stuart Dyke Swarm. Recrystallisation and metamorphic fabric may have developed during the regional Chewings Phase of deformation which in Hermannsburg 1:100 000 Sheet area to the west has been dated by total-rock Rb/Sr at 1620 +/- 70 m.y.|16-MAY-23
24495|Simpsons Gap Metasediments|Proposed publication|Geological report on 1:100 000 scale mapping of southeastern Arunta Block, Alice Springs 1:250 000 Sheet area, Northern Territory by R. D. Shaw et al.  BMR Microfiche report in prep.|16-MAY-23
24495|Simpsons Gap Metasediments|Defn Reference|80/20787|16-MAY-23
24495|Simpsons Gap Metasediments|Proposer|Offe L.A.|16-MAY-23
24495|Simpsons Gap Metasediments|Resdate|18-MAR-1975|16-MAY-23
24495|Simpsons Gap Metasediments|Reserved? Yes/No|Reserved Simpson Gap Metasediments - have since changed to Simpsons Gap Metasediments.|16-MAY-23
17111|South Alligator Group|General description|Definition: Needham and others (1980) extensively redefined the group relative to the description given by earlier workers who first introduced the term (Walpole & others 1968), and included in it the Koolpin Formation, Shovel Billabong Andesite, Gerowie Tuff and Kapalga Formation. Later work (Stuart-Smith & others, 1984a and b) determined fundamental lithological differences in the group east and west of the Waterfall Creek Fault, where to the west the normal sequence exists but to the east volcanic components are absent and no stratigraphic subdivision is possible (Needham & Stuart-Smith, 1984). The name Kapalga Formation is restricted to areas east of the fault. Rocks previously referred to west of the fault as Kapalga Formation (i.e. stratigraphically above the Gerowie Tuff) are renamed Mount Bonnie Formation. Thus the South Alligator Group as redefined contains five formations: Koolpin Formation, Shovel Billabong Andesite, Gerowie Tuff, Mount Bonnie Formation, Kapalga Formation.|16-MAY-23
17111|South Alligator Group|Proposed publication|Needham and Stuart-Smith (in prep.) - changes in strat. Nom. And correlation.  BMR Journal|16-MAY-23
17111|South Alligator Group|Status|1|16-MAY-23
22869|Speares Metamorphics|Name source|Speares Bore 132o 39'E 23o 24'S.|16-MAY-23
22869|Speares Metamorphics|Unit history|Previously mapped as part of the Mount Zeil granulite (informal) of Glikson (1984).|16-MAY-23
22869|Speares Metamorphics|Geomorphic expression|Low rubbly hills.|16-MAY-23
22869|Speares Metamorphics|Type section locality|Hills northeast of Speares Bore near GR 210700 7414400, Glen Helen 1:100 000 Sheet area.|16-MAY-23
22869|Speares Metamorphics|Extent|Extending from north of Glen Helen homestead westwards into the Mount Liebig 1:250 000 Sheet area.|16-MAY-23
22869|Speares Metamorphics|Lithology|Migmatitic quartzofeldspathic gneiss, biotite gneiss, augen gneiss, amphibolite, mafic granulite, metasediments.|16-MAY-23
22869|Speares Metamorphics|Relationships and boundaries|Enclosed between faults of the Redbank Thrust Zone.|16-MAY-23
22869|Speares Metamorphics|Structure and Metamorphism|Occupies a boudin-like fault blocks within the Redbank Thrust Zone. Folded into open folds and metamorphosed to, or close to, granulite facies grade, presumably during the Argilke Tectonic Event at about 1650-1680 Ma. Complexly folded.|16-MAY-23
22869|Speares Metamorphics|Age reasons|Proterozoic, affected by high-grade metamorphism, either Strangways metamorphism or that which affected the Glen Helen Metamorphics to the South, older than the Redbank Thrust Zone at about 1450 Ma (Shaw & Black, 1992).|16-MAY-23
22869|Speares Metamorphics|Defn author|R.G. Warren & R.D. Shaw, 1 July 1991|16-MAY-23
22869|Speares Metamorphics|Comments|This 'definition' is missing the details of references mentioned in the synonymy and age, and shows no signs on the card of having been approved.|16-MAY-23
29406|Spencer Creek Group|Name source|Spencer Creek (lat. 12o20'S, long. 136o25'30"E), which flows into the eastern side of Arnhem Bay. Arnhem Bay 1:250 000 scale mapsheet area.|16-MAY-23
29406|Spencer Creek Group|Unit history|The formations which now collectively make up the Spencer Creek Group were originally mapped as "Spencer Creek Volcanics" by Dunnet (1965), which was subsequently formalised by Plumb and Roberts (1992). This also included some small outcrops now recognised as belonging to the Dhalinybuy Granite and Balbirini Dolomite (Nathan Group) which were not previously mapped in this area.|16-MAY-23
29406|Spencer Creek Group|Constituents|In ascending order; Yanungbi Volcanics, Gove Sandstone, Yuduyudu  Formation, Cato Volcanics and Rorruwuy Sandstone.|16-MAY-23
29406|Spencer Creek Group|Geomorphic expression|Sandstone-dominated formations form resistant and upstanding strike ridges, while the igneous-mudstone units are typically recessive.|16-MAY-23
29406|Spencer Creek Group|Type section locality|Type localities and reference areas as defined for each constituent formation. Plumb and Roberts (1992) did not assign a specific type section, only a loose reference area to the "Spencer Creek Volcanics".|16-MAY-23
29406|Spencer Creek Group|Extent|Restricted to a series of small northeast-striking disconnected ridges stretching between Spencer Creek and Mount Bonner, northeastern Arnhem Bay and northwestern Gove 1:250 000 scale mapsheet areas.|16-MAY-23
29406|Spencer Creek Group|Thickness range|1500 m. Unconformity at the base of overlying units (Mount Bonner Sandstone and Balbirini Dolomite) has reduced the thickness to 200 m locally.|16-MAY-23
29406|Spencer Creek Group|Lithology|Undeformed lithic to quartzose sandstone and conglomeratic sandstone, felsic and mafic igneous rocks, and mudstone.|16-MAY-23
29406|Spencer Creek Group|Depositional environment|Ranges from fluviatile to shallow-water delta-fan for the sedimentary facies; igneous rocks are interpreted as mainly volcanic.|16-MAY-23
29406|Spencer Creek Group|Relationships and boundaries|Unconformably overlies the metamorphic and granitic rocks of the Bradshaw Complex and the Orosirian Dhalinybuy Granite, and is unconformably overlain by coarse-grained siliciclastic rocks of the Mount Bonner Sandstone.|16-MAY-23
29406|Spencer Creek Group|Age reasons|Palaeoproterozoic (Statherian). The maximum age is constrained by the underlying ~1870 Ma Bradshaw Complex. However, a likely comagmatic relationship between the lower-most unit of the group (Yanungbi Volcanics) and the nearby Latram Granite, indicates a maximum age of ~1710 Ma. An indistinguishable age for the Cato Volcanics near the top of the group tightly constrains the majority of the sequence, however, there is no minimum constraining age for the upper-most unit of the group (Rorruwuy Sandstone).|16-MAY-23
29406|Spencer Creek Group|Correlations|The bulk of the group correlates with the Fagan phase within the regional framework of Rawlings (1994), based on geochemical, petrological, lithostratigraphic and geochronological constraints, and the physical form of igneous units. This infers correlation with the upper units of the Tawallah and Katherine River Groups in the southern and western portions of the McArthur Basin respectively. It also includes the upper part of the Donydji Group (Fagan Volcanics) in southern Arnhem Bay/northern Blue Mud Bay 1:250 000 scale mapsheet areas, and possibly the Gadabara Volcanics in eastern Blue Mud Bay. A probable disconformable relationship exists between the Cato Volcanics and overlying Rorruwuy Sandstone, thus not providing a constraint on the minimum age of the group. This allows for possible correlation of this upper-most sandstone unit with the Fleming Sandstone in upper part of the Parsons Range Group.|16-MAY-23
29406|Spencer Creek Group|Proposed publication|Arnhem Bay-Gove 1:250 000 Geological Map Series, NT, National Geoscience Mapping Accord, Explan. Notes.|16-MAY-23
29406|Spencer Creek Group|Comments|The existing definition of the "Spencer Creek Volcanics" does not take into consideration the presence of a mappable internal stratigraphy of both sedimentary and igneous units. For this reason, the succession is renamed as the Spencer Creek Group and is subdivided into five formations.|16-MAY-23
29406|Spencer Creek Group|References|DUNNET, D., 1965- Arnhem Bay/Gove, Northern Territory - 1:250 000 Geological Series. Bureau of Mineral Resources, Australia, Explanatory Notes, SD53-3, 4. **PLUMB, K. A. and ROBERTS, H. G., 1992- The geology of Arnhem Land, Northern Territory, Bureau of Mineral Resources, Australia, Record, 1992/55. **RAWLINGS, D. J., 1994- Characterisation and Correlation of Volcanism in the McArthur Basin and Transitional Domain, N.T. In Proceedings The AusIMM Annual Conference, Darwin, 1994, pp. 157-160 (The Australasian Institute of Mining and Metallurgy: Melbourne). **RAWLINGS, D. J. and others, in prep- Arnhem Bay - Gove, Northern Territory - 1:250 000 Geological Map Series.  National Geoscience Mapping Accord, Explanatory Notes, SD53 -3, 4.|16-MAY-23
37624|Stanley Metamorphics|Name source|After Stanley Creek, 22.5 km NNE of Batchelor, Northern Territory|16-MAY-23
37624|Stanley Metamorphics|Unit history|Referred to as Ar1 unit of Rum Jungle Complex and Aw1 unit of Waterhouse Complex by Crick (1984).|16-MAY-23
37624|Stanley Metamorphics|Type section locality|Eastern side of Rum Jungle Dome, 724400mE, 8565500mN (lat. 131o 4' E, long 12o 58' S).|16-MAY-23
37624|Stanley Metamorphics|Extent|Stanley Metamorphics occur as scattered outcrops concentrated in the central-eastern side of the Rum Jungle Dome 10 km NE of Batchelor, Northern Territory and as inclusions within granitic rocks elsewhere in the Rum Jungle Dome and within the Waterhouse Dome in BYNOE, NOONAMAH and REYNOLDS RIVER 1:100 000 sheets.|16-MAY-23
37624|Stanley Metamorphics|Thickness range|Unknown|16-MAY-23
37624|Stanley Metamorphics|Lithology|Various metasedimentary schists and gneisses, including biotite gneiss, biotite-muscovite gneiss, quartz-muscovite schist, thinly banded feldspathic gneiss, chlorite schist, actinolite schist and banded ironstone.|16-MAY-23
37624|Stanley Metamorphics|Relationships and boundaries|Part of the Rum Jungle Complex..  Intruded by granitic phases of the Rum Jungle Complex, unconformably overlain by Beestons Formation. Boundary between Stanley Metamorphics and granitic rocks of the Rum Jungle Complex is intrusive.|16-MAY-23
37624|Stanley Metamorphics|Identifying features|Metasedimentary rocks within granitic Rum Jungle Complex.|16-MAY-23
37624|Stanley Metamorphics|Age reasons|Older than 2535 Ma, the age of Waterhouse Complex granitoid determined by SHRIMP U-Pb zircon dating (NTGS unpublished data).|16-MAY-23
37624|Stanley Metamorphics|Correlations|Possible correlation with Dirty Water Metamorphics, which unconformably overlie 2675 Ma Woolner Granite (Pietsch and Stuart-Smith, 1987).|16-MAY-23
17395|Strangways Metamorphic Complex|Name source|The Complex is named after Strangways Range which spans central and northwestern Alice Springs 1:250 000 Sheet area. (This is an extended usage approved by the NT Lands Branch and National Mapping and shown on latest 1:250 000 topographic map).|16-MAY-23
17395|Strangways Metamorphic Complex|Unit history|Previously published as Strangways Range Metamorphic Complex by Shaw & Warren (1975). The name is now changed to Strangways Metamorphic Complex for brevity.|16-MAY-23
17395|Strangways Metamorphic Complex|Constituents|The Complex includes the Utnalanama Granulite, Harry Anorthositic Gabbro, the Erontonga metamorphics, the Cadney metamorphics, the Yambah granulite, the Ongeva granulite, and the Bungitina metamorphics in the Alice Springs 1:250 000 Sheet area. The Complex also includes the Mount Bleechmore Granulite and the Kanandra Granulite in the Alcoota 1:250 000 Sheet area (Shaw & Warren, 1975). The Ingula Migmatite Suite and the Wuluma Granite are considered to have   formed during the ultrametamorphism which has affected the entire complex and are also included in it.|16-MAY-23
17395|Strangways Metamorphic Complex|Type section locality|Strangways Range is the type area. A reference section between GR 5751-042263 and Southern Cross Bore (GR 5751-191395) is representataive of the lower part of the Complex. jA reference section between the White Lady Mica Mine and White Hill Dam in northeastern Alice Springs 1:250 000 Sheet area is a representative section of the upper part of the Complex because its boundary with the overlying Harts Range Group is clearly displayed.|16-MAY-23
17395|Strangways Metamorphic Complex|Extent|Northwestern and northern central Alice Springs 1:250 0000 Sheet area, and southern central and central-eastern Alcoota 1:250 000 Sheet area.|16-MAY-23
17395|Strangways Metamorphic Complex|Lithology|Mainly mafic and felsic granulites and lesser amounts of cordierite and sillimanite-bearing gneisses. The upper part of the Complex also contains calc-silicate rock, marble, sillimanite gneiss, schistose biaotite gneiss, and layered amphibolite.|16-MAY-23
17395|Strangways Metamorphic Complex|Relationships and boundaries|The unit is overlain by the Irindina Gneiss (Joklik, 1955) of the Harts Range Group between Old (Schaber) Station Well and White Hill Dam. The contact is slightly discordant in that there is a distinct change in rock type, an abarupt increase in the continuity of compositional layering, and in a sharp decrease in the amount of minor folding. Farther west (north of the Oonagalabi Prospect) the contact becomes clear angular discordance, but the presence of a deformed zone containing numerous intrafolial folds and small thrust faults makes the nature of the contact difficult to assess. The Strangways Metamorphic Complex contains much less garnet in its biotite gneiss, and includes abundant quartzofeldspathic gneiss not apparent in the Irindina Gneiss. Cross-cutting mafic granulite and amphibolite bodies (meta-gabbros) are common in the Strangways Metamorphic Complex, but very rare and generally absent from the Harts Range Group. Compositional units tend to be much more continuous in the Harts Range Group. The Complex is thought to be an older basement (Division 1) below the other rocks (Divisions 2 and 3) in the Arunta Block.|16-MAY-23
17395|Strangways Metamorphic Complex|Age reasons|A widespread metamorphism which affeacts the entire Complex has been datead by Black (1975) at about 1800 m.y. and at 1860 +/- 70 m.y. by Iyer, Woodford & Wilson (1976).|16-MAY-23
17395|Strangways Metamorphic Complex|Proposed publication|Stewart & others in prep.|16-MAY-23
17395|Strangways Metamorphic Complex|Defn Reference|80/20787|16-MAY-23
17395|Strangways Metamorphic Complex|Name first published by|Shaw R.D., Warren R.G., Kopras J., Green D.E., 1975|16-MAY-23
17418|Stray Creek Sandstone|Type section locality|As per Walpole et al. (1968), reference [type] area: tributaries of Stray Creek, lat. 13deg53' S, 131deg 38' E, but best developed [reference areas] in Rock Candy Range and east of Buldiva.|16-MAY-23
17418|Stray Creek Sandstone|Identifying features|The unit was first published by White and others (1963) and later more fully defined by Walpole and others (1968), as the Stray Creek Sandstone Member of the Bluldiva Sandstone, Tolmer Group. As it is an extensive, individually mappable unit its status is now elevated from member to formation, and the name Buldiva Sandstone is discarded.|16-MAY-23
17418|Stray Creek Sandstone|Proposed publication|Dundas D.L., Edgoose C.J., Fahey G.M., Fahey J.E., in prep. Explanatory Notes for Daly River (5070). Northern Territory Geological Survey 1:100 000 Geological Map Series (Darwin: Northern Territory Govrnment Printer).|16-MAY-23
17418|Stray Creek Sandstone|References|B082; 01/31590.|16-MAY-23
25695|Strzeleckie Volcanics|Name source|Mount Strzeleckie (AMG GR LS832608) at the northern end of Crawford Range on the Crawford 1:100 000 sheet (5655).|16-MAY-23
25695|Strzeleckie Volcanics|Unit history|Originally mapped as undifferentiated Arunta Block or as unnamed quartz feldspar porphyry (Smith and Milligan, 1964).|16-MAY-23
25695|Strzeleckie Volcanics|Geomorphic expression|Generally recessive, but can form undulating terrain and low ridges with pale to dark air photo tones adjacent to higher ridges of the Illoquara Sandstone.|16-MAY-23
25695|Strzeleckie Volcanics|Type section locality|In northwestern corner of Taylor 1:100 0000 sheet; base at AMG GR LS967580 (latitude 21o10'36"S, longitude 134o00'17"E); top at GR LS982590 (latitude 21o10'03"S, longitude 134o02'10"E).|16-MAY-23
25695|Strzeleckie Volcanics|Extent|Around the edges of the Osborne and Crawford ranges on the Crawford and Taylor (5755) 1:100 0000 sheets.|16-MAY-23
25695|Strzeleckie Volcanics|Thickness range|About 1700 m at the type section; up to 500 m in the Crawford Range.|16-MAY-23
25695|Strzeleckie Volcanics|Lithology|(in decreasing order of abundance): Tuff: very fine-grained, thinly bedded, commonly altered and iron-stained; Tuffaceous siltstone: fine- to medium-grained, poorly sorted, angular-grained, with clayey/sericitic matrix; Porphyritic lava, crops out mainly near Osborne Range, dacitic to rhyolitic, medium to coarse, tabular phenocrysts of plagioclase in a dark grey to black cryptocrystalline matrix; Quartz arenite, minor ridge-forming, medium-grained, medium- to thick-bedded variably feldspathic/lithic; Partly recrystallised and foliated porphyritic rhyolite-dacite, minor trachyandesite, feldspathic quartz arenite, micaceous arenite, and quartz-biotite schist are exposed to the southeast of Osborne Range around AMG GR MS197425.|16-MAY-23
25695|Strzeleckie Volcanics|Relationships and boundaries|Conformably overlies the Gwynne Sandstone and is conformably overlain by, and in places interfingers with the Tinfish Sandstone in the region of the type section. Sharply and probably disconformably overlain by the Illoquara Sandstone in the southeast Osborne Range area (e.g. at AMG GM MS149372) and Crawford Range. Intruded by Ali Curung Granite and an unnamed granite southeast of Osborne Range. The Strzeleckie Volcanics are included in the Wauchope Subgroup of the Hatches Creek Group.|16-MAY-23
25695|Strzeleckie Volcanics|Identifying features|Defined in Haines et al., 1991 (proposed publication).|16-MAY-23
25695|Strzeleckie Volcanics|Structure and Metamorphism|Steeply dipping and open to tightly folded, faulted.|16-MAY-23
25695|Strzeleckie Volcanics|Age reasons|The maximum age of the Hatches Creek Group is considered to be Early Proterozoic (Blake and others, 1987).|16-MAY-23
25695|Strzeleckie Volcanics|Correlations|Possible correlative of Newlands Volcanics (Blake and others, 1985).|16-MAY-23
25695|Strzeleckie Volcanics|Proposed publication|Barrow Creek 1:250 000 Geol. Series, Explan. Notes, NT Geological Survey.|16-MAY-23
25695|Strzeleckie Volcanics|Category|2|16-MAY-23
25695|Strzeleckie Volcanics|Proposer|Bagas L., Wyche S.|16-MAY-23
22910|Stuart Pass Dolerite|Name source|Stuart Pass 133o20'E, 23o44'S.|16-MAY-23
22910|Stuart Pass Dolerite|Unit history|Previously Stuart Dykes, Stuart Dyke Swarm, Stuart dolerite (informal).|16-MAY-23
22910|Stuart Pass Dolerite|Geomorphic expression|Low ridges of dark rock; recessive relative to resistant units, e.g., Chewings Range Quartzite.|16-MAY-23
22910|Stuart Pass Dolerite|Type section locality|GR 245300 7374100 MacDonnell Ranges Sheet area (dyke adjacent to the road to Standley Chasm).|16-MAY-23
22910|Stuart Pass Dolerite|Extent|Southern Arunta Province, from Undoolya 1:100 000 Sheet area to west of papunya.|16-MAY-23
22910|Stuart Pass Dolerite|Lithology|Olivine-bearing dolerite.|16-MAY-23
22910|Stuart Pass Dolerite|Relationships and boundaries|Cut by narrow mylonites of Alice Springs age, overlain by Heavitree Quartzite, cuts wide deformed zones of Chewings Deformation.|16-MAY-23
22910|Stuart Pass Dolerite|Structure and Metamorphism|Commonly near north-south dykes, some east-west dykes in northwest.|16-MAY-23
22910|Stuart Pass Dolerite|Age reasons|1060 Ma (Camacho et al. 1991), 1080 Ma (Zhao & McCulloch, 1993).|16-MAY-23
22910|Stuart Pass Dolerite|Correlations|Kulgera Dyke Swarm (Camacho et al. 1991).|16-MAY-23
22910|Stuart Pass Dolerite|Defn author|R.D. Shaw, R.G. Warren, C. Teyssier & G.A. Wakelin-King, 1992.|16-MAY-23
22910|Stuart Pass Dolerite|Comments|This 'definition' is missing the details of references mentioned in the age and synonymy, and shows no signs on the card of having been approved.|16-MAY-23
27664|Sweets Member|Name source|Sweets lookout GR FL713744 on Bynoe 1:100 000 Sheet (5072).|16-MAY-23
27664|Sweets Member|Type section locality|In drill hole LKN20, coordinates FL657820, intesected between 70 m-420 m. Core is currently held by Idemitsu Uranium Exploration Australia Pty Ltd and on expiration of tenement shall be held by the NT Department of Mines and Energy, Darwin.|16-MAY-23
27664|Sweets Member|Extent|Bynoe, Fog Bay, Anson and Reynolds River 1:100 0000 sheet areas. Very poor, to non-outcropping.|16-MAY-23
27664|Sweets Member|Thickness range|Unknown|16-MAY-23
27664|Sweets Member|Lithology|Marble, in places graphitic; para-amphibolite, diopside +/- tremolite gneiss; quartz-feldspar-biotite gneiss in places graphitic.|16-MAY-23
27664|Sweets Member|Relationships and boundaries|The member occurs within the Welltree Metamorphics. Top unit consists of diopside +/- tremolite gneiss containing amphibolite bands. The bottom unit consists of marble. The member's amphibolite and marble content distinguishes it from the rest of the Welltree Metamorphics.|16-MAY-23
27664|Sweets Member|Age reasons|Early Proterozoic because - (1) it occurs as a member within the Welltree Metamorphics; (2) age dating (by W.A.I.T. for NTGS) Rb/Sr 1785 +/- 101 m.y., Nd-Sm 2150 +/- 40 m.y.|16-MAY-23
27664|Sweets Member|Proposed publication|Explanatory Notes Bynoe 1:100 000 sheet area (Northern Territory Geological Survey)|16-MAY-23
37706|Talipata Granite|Name source|Talipata Gorge 23o 22' 50" S, 131o 22' 20" E, MOUNT LIEBIG.|16-MAY-23
37706|Talipata Granite|Unit history|Previously included within undifferentiated gneiss, schist, amphibolite, quartzite, granite, dolerite and pegmatite of the Arunta Complex  (Ranford 1969)|16-MAY-23
37706|Talipata Granite|Geomorphic expression|Prominent rounded hills|16-MAY-23
37706|Talipata Granite|Type section locality|10 km west of Berry Pass at location 23o 20' 28.57" S, 131o 17' 03.10" E (WGS 84), MOUNT LIEBIG.|16-MAY-23
37706|Talipata Granite|Description at type locality|Foliated porphyritic biotite-hornblende granite with phenocrysts of K-feldspar and a mineral assemblage comprising quartz, K-feldspar, plagioclase, biotite, hornblende, titanite and opaque oxides.|16-MAY-23
37706|Talipata Granite|Extent|In valley between Mount Palmer and western extension of Belt Range, MOUNT LIEBIG.|16-MAY-23
37706|Talipata Granite|Lithology| Foliated, coarse grained, porphyritic biotite and biotite-hornblende granite. The rock contains phenocrysts of K-feldspar typically 1-2 cm in diameter that are flattened and elongated in a well-developed fabric that is locally gneissic. The dominant mafic mineral is biotite, with variable amounts of hornblende, and minor titanite and Fe-Ti oxides. The granite has locally undergone pervasive greenschist facies retrogression.|16-MAY-23
37706|Talipata Granite|Relationships and boundaries|Has ambiguous highly strained intrusive or tectonic contact with metasedimentary rocks of the Lizard Schist.  In faulted contact with Peculiar Complex. Unconformably overlain by Heavitree Quartzite|16-MAY-23
37706|Talipata Granite|Age reasons|late Palaeoproterozoic. Granite from 23o 21' 58.94" S, 131o 20' 50.14" E has a SHRIMP U-Pb zircon age of 1683 +/- 2 Ma (Cross et al, in prep).|16-MAY-23
37706|Talipata Granite|Correlations|No known direct correlatives, but is a similar age to volcanics and leucogranites of the Peculiar Complex, and felsic migmatites in the Glen Helen Metamorphics (Warren and Shaw 1995).|16-MAY-23
37706|Talipata Granite|Comments|Deformed and metamorphosed at lower to middle amphibolite facies conditions during the 1590-1560 Ma Chewings Orogeny, with localised greenschist facies retrogression.|16-MAY-23
37706|Talipata Granite|References|Cross A, Claoue-Long J, Scrimgeour IR, Close DF & Edgoose CJ, in prep. NTGS-GA Geochronology project, Report 6. Northern Territory Geological Survey, Record  **Ranford LC, 1969. Mount Liebig, Northern Territory (First Edition). 1:250 000 geological map series explanatory notes, SF52-16. Bureau of Mineral Resources, Australia. **Scrimgeour IR, Close DF & Edgoose CJ, in prep. Mount Liebig, Northern Territory (Second Edition) 1:250 000 geological map series explanatory notes, SE 52-16. Northern Territory Geological Survey, Darwin. **Warren RG and Shaw RD 1995. Hermannsburg, Northern Territory (Second Edition). 1:250 000 geological map series explanatory notes, SF-53-13. Northern Territory Geological Survey, Darwin.|16-MAY-23
41852|Talyi-Talyi Charnockite|Name source|Talyi-Talyi Hills 23o 12' 00" S, 131o 12' 00" E, MOUNT LIEBIG.|16-MAY-23
41852|Talyi-Talyi Charnockite|Unit history|Previously included within undifferentiated gneiss, schist, amphibolite, quartzite, granite, dolerite and pegmatite of the Arunta Complex  (Ranford 1969)|16-MAY-23
41852|Talyi-Talyi Charnockite|Geomorphic expression|Prominent, often steep-sided hills with bouldery outcrop|16-MAY-23
41852|Talyi-Talyi Charnockite|Type section locality|Hill 3 km south-southwest of Talyi-Talyi Hills, at location 23o13'53.29"S, 131o10'44.96"E (WGS 84), MOUNT LIEBIG.|16-MAY-23
41852|Talyi-Talyi Charnockite|Description at type locality|Medium grained, weakly porphyritic, foliated charnockite, with blue-grey phenocrysts of plagioclase feldspar up to 8 mm in diameter, with metamorphic garnet and hornblende.|16-MAY-23
41852|Talyi-Talyi Charnockite|Extent| In Talyi-Talyi and Tjungkubu Hills and in scattered hills extending east to Yaya  Creek, MOUNT LIEBIG.|16-MAY-23
41852|Talyi-Talyi Charnockite|Lithology|Igneous ortho- and clinopyroxene is only rarely preserved, and is largely replaced by a metamorphic assemblage including hornblende, biotite, garnet and secondary clinopyroxene, associated with a variably developed structural fabric.|16-MAY-23
41852|Talyi-Talyi Charnockite|Relationships and boundaries|Has intrusive contacts with Tjungkubu Granodiorite, but no clear relative timing relationships. Faulted contacts with Yaya Metamorphic Complex.|16-MAY-23
41852|Talyi-Talyi Charnockite|Age reasons|late Palaeoproterozoic. Sample from type locality has a SHRIMP U-Pb zircon age of 1631 +/- 4 Ma (Cross et al in prep).|16-MAY-23
41852|Talyi-Talyi Charnockite|Correlations|Directly correlated with Russell Charnockite. Strong geochemical affinity with other granites of the Waluwiya Suite ? Larrie Granodiorite, Kakalyi Gneiss, Tjungkubu Granodiorite and Russell Charnockite|16-MAY-23
41852|Talyi-Talyi Charnockite|References|Cross A, Claoue-Long J, Scrimgeour IR, Close DF & Edgoose CJ, in prep. NTGS-GA Geochronology project, Report 6. Northern Territory Geological Survey, Record  **Ranford LC, 1969. Mount Liebig, Northern Territory (First Edition). 1:250 000 geological map series explanatory notes, SF52-16. Bureau of Mineral Resources, Australia. **Scrimgeour IR, Close DF & Edgoose CJ, in prep. Mount Liebig, Northern Territory (Second Edition) 1:250 000 geological map series explanatory notes, SE 52-16. Northern Territory Geological Survey, Darwin.|16-MAY-23
41852|Talyi-Talyi Charnockite|Parent|Waluwiya Suite|16-MAY-23
17763|Tanami Group|Name source|Tanami Range, (GDA94) 20deg00'S, 129deg38'E, TANAMI.|16-MAY-23
17763|Tanami Group|Unit history|Tanami Metamorphic Series (Jensen 1915) in part; Tanami Complex (Plumb and Derrick 1974); Tanami complex (Blake et al 1975), which included rocks of current Tanami Group as well as of younger Ware Group and Mount Charles Formation; Tanami Group (Cooper and Ding 1997), which included current Dead Bullock and Killi Killi Formations as well as a lower quartzite interpreted as a basal sedimentary unit; this basal quartzite has not been identified as sedimentary and is not included in Tanami Group. See also synonymies of constituent units.|16-MAY-23
17763|Tanami Group|Constituents|In ascending order Dead Bullock Formation (Hendrickx et al 2000) including Ferdies and Callie Members (Crispe and Vandenberg in Wygralak et al 2005), Killi Killi Formation (Hendrickx et al 2000), all defined herein.|16-MAY-23
17763|Tanami Group|Geomorphic expression|Generally forms low-relief outcrop that is typically heavily ferruginised. Dead Bullock Formation forms discontinuous ferruginous strike ridges, low ferricrete rises or rubbly chert ridges. Killi Killi Formation generally forms sporadic low outcrops, partially covered by Quaternary sediments or ferricrete. Typically weathered to grey or purple saprolite or leached exposures below an indurated ferruginous cap.|16-MAY-23
17763|Tanami Group|Type section locality|As for constituent units.|16-MAY-23
17763|Tanami Group|Extent|Northern Territory: southern TANAMI, THE GRANITES, MOUNT SOLITAIRE, MOUNT THEO, northern HIGHLAND ROCKS. Western Australia: eastern BILLILUNA, northeastern LUCAS.|16-MAY-23
17763|Tanami Group|Thickness range|Combined thickness estimates for constituent units total minimum 1800 m, but more likely to be in order of 3000-4200 m.|16-MAY-23
17763|Tanami Group|Lithology|As for constituent units.|16-MAY-23
17763|Tanami Group|Depositional environment|Deep water, low energy, low sediment supply with rapid transition to turbidite emplacement.|16-MAY-23
17763|Tanami Group|Diastems or hiatuses|Possible hiatus at transition from Dead Bullock Formation to Killi Killi Formation.|16-MAY-23
17763|Tanami Group|Relationships and boundaries|Thick immature arkosic beds at Groundrush suggest that lowest unit of Tanami Group, Ferdies Member of Dead Bullock Formation, overlies gniessic or granitic basement. No top observed to highest constituent stratigraphic unit, the jasper chert lithofacies of Killi Killi Formation. Tanami Group intruded by numerous granite plutons, oldest (though slightly equivocal) age of these being 1844+/- 4 Ma ('Inspiration Peak Monzogranite' of Dean (2001), now an unnamed granite in Frederick Suite; Claoué-Long et al 2001). Tanami Group has undergone deformation and metamorphism during Tanami Event at 1835-1825 Ma. Ware Group is interpreted to unconformably overlie Tanami Group.|16-MAY-23
17763|Tanami Group|Age reasons|Orosirian. Youngest detrital zircon populations in samples of Tanami Group suggest maximum deposition age of ~1840 Ma (Cross et al 2003). A tuff intercalated with Callie Member of Dead Bullock Formation has SHRIMP U-Pb zircon age of 1838 ± 4 Ma (Cross et al 2005). Intruded by 'Watertower tonalite' of Cooper and Ding (1997) north of The Granites mine at 1821 ± 4 Ma (Smith 2000).|16-MAY-23
17763|Tanami Group|Correlations|Killi Killi Formation of Tanami Group interpreted to be correlative of Lander Rock beds in Arunta Region. Parts of Tanami Group apparent time equivalent of basal Ooradidgee Group in Tenannt Region.|16-MAY-23
17763|Tanami Group|Proposed publication|Crispe AJ and Vandenberg LC, in press. Geology of the Tanami Region, Northern Territory. NTGS Report.|16-MAY-23
17763|Tanami Group|References|Blake DH, Hodgson IM and Smith PA, 1975. Geology of the Birrindudu and Tanami 1:250 000 sheet areas, Northern Territory. Bureau of Mineral Resources, Australia, Report 174.**Cooper JA and Ding PQ, 1997. Zircon ages constrain the timing of deformation events in the The Granites-Tanami region, northwest Australia. Australian Journal of Earth Sciences 44, 777-787.**Cross AJ, Claoué-Long J and Crispe AJ, 2003. Summary of results. Joint NTGS-GA geochronology project: Tanami Region 2001-2002. Northern Territory Geological Survey, Record 2003-006.**Cross AJ, Fletcher IR, Crispe AJ, Huston DL and Williams N, 2005a. New constraints on the timing of deposition and mineralisation in the Tanami Group: in 'Annual Geoscience Exploration Seminar (AGES) 2004. Record of abstracts'. Northern Territory Geological Survey, Record 2004-001.**Dean AA, 2001. Igneous rocks of the Tanami Region. Northern Territory Geological Survey, Record 2001-003.**Hendrickx MA, Slater KR, Crispe AJ, Dean AA, Vandenberg LC and Smith JB, 2000. Palaeoproterozoic stratigraphy of the Tanami Region: regional correlations and relation to mineralisation - preliminary results. Northern Territory Geological Survey, Record GS2000-13.**Jensen HI, 1915. Report on the country between Pine Creek and Tanami. Northern Territory of Australia Bulletin 14.**Plumb KA and Derrick GM, 1974. Geology of the Kimberley to Mount Isa region, northern Australia, 1:2 500 000 geological map (First Edition). Bureau of Mineral Resources, Australia, Canberra.**Smith JB, 2000. NTGS-AGSO Geochronology Project, Report 3. Geoscience Australia, Professional Opinion 2000/27.**Wygralak AS, Mernagh TP, Huston DL and Ahmad M, 2005. Gold mineral system of the Tanami Region. Northern Territory Geological Survey, Report 18.|16-MAY-23
17763|Tanami Group|Proposer|Marc Hendrickx, after Jensen (1915), Cooper and Ding (1997).|16-MAY-23
24513|Taragan Sandstone|Name source|Taragan Waterhole on Lennee Creek, at GR 057102, Hatches 1:100 000 Sheet area, Frew River 1:250 000 Sheet area.|16-MAY-23
24513|Taragan Sandstone|Type section locality|In eastern Davenport Range 1:100 000 Sheet area, from GR 956064 (base), 2 km west of Great Davenport Au prospect (latitude 20o45'50"S, longitude 134o58'25"E), to GR 944073 (top). Section is 600 m thick and consists of 3 informal members: lower member, 220 m thick, of strongly cross-bedded medium to pebbly arenite with siltstone interbeds near base; middle member, 50 m thick, of fine-grained lithic arenite and, at top, minor coarser quartz arenite; and upper member, 330 m thick, of pebbly arenite and pebble conglomerate. The formation here overlies Kurinelli Sandstone with local unconformity and is overlain conformably by Treasure Volcanics.|16-MAY-23
24513|Taragan Sandstone|Extent|Central part of the Davenport Province - southern part of Bonney Well, southwestern part of Frew River, and north-eastern part of Barrow Creek 1:250 000 Sheet areas.|16-MAY-23
24513|Taragan Sandstone|Thickness range|0 to 1200 m.|16-MAY-23
24513|Taragan Sandstone|Lithology|Ridge-forming pebbly quartz arenite and feldspathic/lithic quartz arenite; also pebble to boulder conglomerate, non-pebbly arenite, and recessive siltstone, mudstone, friable arenite and altered felsic lava in some areas.|16-MAY-23
24513|Taragan Sandstone|Relationships and boundaries|Conformable between non-pebbly arenite of the Kurinelli Sandstone below and lava of the Treasure Volcanics above, and interfingers with parts of these two formations; also overlain conformably by less pebbly arenite of the Unimbra Sandstone (in west). Locally unconformable on the Kurinelli Sandstone.|16-MAY-23
24513|Taragan Sandstone|Age reasons|Younger than 1870 m.y. - U-Pb zircon age of volcanics within the Warramunga Group unconformably underlying the Hatches Creek Group. Older than 1640 m.y. - Rb-Sr whole rock age of granite intruding the Hatches Creek Group.|16-MAY-23
24513|Taragan Sandstone|Defn author|Blake D.H., Stewart A.J., Sweet I.P., Wyche S., 1985.|16-MAY-23
24513|Taragan Sandstone|Proposed publication|Blake D.H., Stewart A.J., Sweet I.P., Wyche S., 1985. Definitions of newly named and revised Precambrian rock units in the Davenport and Murchison Ranges of central Australia (Northern Territory). Bureau of Mineral Resources, Geology and Geophysics Report 257|16-MAY-23
24513|Taragan Sandstone|Comments|Remarks. Ridge-forming formation of the Ooradidgee Subgroup, Hatches Creek Group, characterised by pebbly arenite.|16-MAY-23
24513|Taragan Sandstone|Defn Reference|86/25362|16-MAY-23
24513|Taragan Sandstone|Proposer|Sweet I.P|16-MAY-23
24513|Taragan Sandstone|Resdate|07-OCT-1981|16-MAY-23
80346|Tarlton Bore Granite|Name source|After Tarlton Bore (654142 mE 7488393 mN, GDA94, Zone53) in Tarlton 1:100 000 map sheet, Northern Territory.|16-MAY-23
80346|Tarlton Bore Granite|Unit history|Previously Jervois Granite (Pge) on the second edition Huckitta 1:250 000 map sheet (Freeman et al 1986). The name Tarlton Granite was used in  Beyer et al. (2018), but Tarlton Bore Granite is preferred here to avoid any risk of confusion with the Tarlton Granite used in Victoria.|16-MAY-23
80346|Tarlton Bore Granite|Geomorphic expression|Low rises and less commonly, small prominent hills; subcrop is widespread and occurs on the flats between more substantial outcrop.|16-MAY-23
80346|Tarlton Bore Granite|Type section locality|634618mE 7482134mN (GDA94, Zone53), approximately 11 km southwest of Unca Hill.|16-MAY-23
80346|Tarlton Bore Granite|Extent|Extensive outcrop over an approximately 120 km2 area southeast of the Jervois Range in eastern Jervois Range 1:100 000 map sheet area and western Tarlton 1:100 000 map sheet area.|16-MAY-23
80346|Tarlton Bore Granite|General description|Scattered outcrop of mica-poor leucogranite that is deeply weathered to rottenstone; weakly to moderately foliated; intrusive relationships with other units are difficult to resolve because of poor exposure.|16-MAY-23
80346|Tarlton Bore Granite|Lithology|Leucogranite: pink to orange-pink, blocky to rubbly, deeply weathered to rottenstone, locally bleached. Characterised by medium-grained, inequigranular to weakly porphyritic mineral assemblage of quartz-K-feldspar-plagioclase+/-biotite. Mica is generally not abundant. Where biotite is present (eg at 649467mE 7492193mN), it comprises less than 3 vol% with brown to red-brown pleochroism, and is variably replaced by chlorite. Minor secondary muscovite after sericite is variably developed.|16-MAY-23
80346|Tarlton Bore Granite|Depositional environment|Interpreted to have formed during migmatitisation of a precursor igneous rock of the Baikal Supersuite.|16-MAY-23
80346|Tarlton Bore Granite|Relationships and boundaries|Contact relationships with other units in the region are generally not exposed, although the Tarlton Bore Granite is interpreted to intrude Attutra Metagabbro, and to be itself intruded by the Boundary Igneous Complex. An unconformable contact between the Tarlton Bore Granite and the Yackah beds of the Georgina Basin is exposed at 647730mE 7477948mN.|16-MAY-23
80346|Tarlton Bore Granite|Identifying features|Distinguished from other igneous units in the area by its highly weathered condition, generally mica-free mineral assemblage, and less well-developed foliation fabric.|16-MAY-23
80346|Tarlton Bore Granite|Structure and Metamorphism|Weakly to moderately foliated with elongate quartz and biotite where present, in the most strongly weathered outcrops structural fabrics are generally not discernible; intruded pre- or syn-tectonic with respect to regional high-thermal-gradient amphibolite-facies metamorphism.|16-MAY-23
80346|Tarlton Bore Granite|Age reasons|An attempt to directly date the Tarlton Bore Granite using LA¿ICP¿MS U¿Pb zircon dating was unsuccessful as all the analysed zircons exhibited high degrees of isotopic disturbance (Beyer et al 2018). A foliated leucogranite dyke intruding ca 1.77 Ga Jervois Granodiorite at 645180mE 7489019mN is potentially related to the Tarlton Bore Granite and hence indicates a maximum crystallisation age for the Tarlton Bore Granite. The foliation fabric in the Tarlton Bore Granite is interpreted as forming at ca 1.76 Ga and provides a minimum crystallisation age for the intrusive (Reno et al 2016).|16-MAY-23
80346|Tarlton Bore Granite|Alteration and Mineralisation|Generally feldspars are partially to completely altered to sericite; biotite flakes show replacement by chlorite. K-feldspar shows partial replacement by very fine-grained granular hematite. Minor secondary muscovite after sericite is variably developed. White quartz veining is common throughout the Tarlton Bore Granite. Strong K-feldspar-quartz and iron oxide alteration and brecciation is common in proximity to the Lucy Creek Fault Zone. There is no known mineralisation in the Tarlton Bore Granite.|16-MAY-23
80346|Tarlton Bore Granite|Geophysical Expression|Irregular, variable magnetic signals; locally distinct magnetic high trends that indicate km-scale folding and re-folding.|16-MAY-23
80346|Tarlton Bore Granite|Geochemistry|Weakly to strongly peraluminous I-type monzogranite and syenogranite.|16-MAY-23
80346|Tarlton Bore Granite|Defn author|Anett Weisheit, Barry Reno, Eloise Beyer (Department of Primary Industry and Resources, Northern Territory Geological Survey), 30-JAN-2019.|16-MAY-23
80346|Tarlton Bore Granite|References|Beyer EE, Reno BL, Weisheit A, Whelan JA, Thompson JM, Meffre S and Woodhead JD, 2018. Summary of results. NTGS laser ablation ICP¿MS U-Pb-Hf geochronology project: selected samples from JERVOIS RANGE 1:100 000 and TOBERMOREY 1:250 000 mapsheets, Aileron and Irindina provinces, January 2014 ¿ December 2016. Northern Territory Geological Survey, Record 2018-001.  **Freeman MJ, Black LA, Offe LA, Senior BR, Shaw RD, Shergold JH, Simpson CJ, Walter MR, Warren RG, Donnellan N, Horsfall CJ, Laurie JR and Walley AM, 1986. Huckitta, Northern Territory (Second Edition). 1:250 000 geological map series, SF 53-11. Northern Territory Geological Survey, Darwin.  **Reno BL, Whelan JA, Weisheit A, Kraus S, Beyer EE, Meffre S and Thompson J, 2016. Summary of Results. NTGS laser ablation ICP¿MS in situ monazite geochronology project: Arunta Region, July 2013¿June 2014. Northern Territory Geological Survey, Record 2016-004.|16-MAY-23
29770|Teapot Granite Complex|Name source|Teapot Yard GR.|16-MAY-23
29770|Teapot Granite Complex|Unit history|Previously mapped as undivided Arunta Complex (Quinlan & Forman 1968), Teapot granite (informal, Glikson 1984) and Ormiston migmatite (informal, Shaw et al. 1984).|16-MAY-23
29770|Teapot Granite Complex|Geomorphic expression|Tors.|16-MAY-23
29770|Teapot Granite Complex|Type section locality|Tors 4km north of Teapot Yard at GR 251000 7403600, Narwietooma 1:100 000 Sheet area.|16-MAY-23
29770|Teapot Granite Complex|Extent|From northwest of Fish Hole on Ellery Creek to southwest of Glen Helen homestead.|16-MAY-23
29770|Teapot Granite Complex|Lithology|Megacrystic granite, even-grained granite, migmatites with abundant (>80 percent) mobilizate.|16-MAY-23
29770|Teapot Granite Complex|Relationships and boundaries|Intrudes Glen Helen Metamorphics.|16-MAY-23
29770|Teapot Granite Complex|Structure and Metamorphism|The granite is considered to be anatectic. It is surrounded by a zone of intense migmatisation, where folding is very complex to clastic.|16-MAY-23
29770|Teapot Granite Complex|Age reasons|1160 Ma (ion-microprobe age of zircon, Black & Shaw, 1992b).|16-MAY-23
29770|Teapot Granite Complex|Defn author|R.D. Shaw, 1995.|16-MAY-23
29770|Teapot Granite Complex|Comments|This 'definition' is missing the details of references mentioned in the age and unit history, and shows no signs on the card of having been approved.|16-MAY-23
17944|Temple Bar Sandstone Member|Name source|Temple Bar Gap (GR 37203736) in the Alice Springs 1:250 000 Sheet area.|16-MAY-23
17944|Temple Bar Sandstone Member|Unit history|The Heavitree Quartzite has been previously undivided (Wells & others, 1968) except informally in the Arltunga Nappe Complex (Shaw & others, 1971).|16-MAY-23
17944|Temple Bar Sandstone Member|Type section locality|Heavitree Gap (GR. 3845 3745)|16-MAY-23
17944|Temple Bar Sandstone Member|Extent|From Arltunga in eastern-central Alice Springs 1:250 000 Sheet area to Mangeraka Gorge, 43 km west-southwest of Haast Bluff in Mount Liebig 1:250 000 Sheet area.|16-MAY-23
17944|Temple Bar Sandstone Member|Thickness range|112 m.|16-MAY-23
17944|Temple Bar Sandstone Member|Lithology|Very fine to fine-grained quartz sandstone, characteristically containing a trace of weathered feldspar. The lower beds are generally medium to thick bedded and the upper beds are thin to medium bedded.|16-MAY-23
17944|Temple Bar Sandstone Member|Relationships and boundaries|Conformably overlies the Undoolya Siltstone Member. The Fenn Gap Conglomerate Member overlies the Member with a local disconformity.|16-MAY-23
17944|Temple Bar Sandstone Member|Age reasons|Upper Proterozoic. (The Heavitree Quartzite unconformably overlies the Stuart Dyke swarm dated at about 900 m.y. by Black, Shaw & Offe (in prep.). The Bitter Springs Formation, which conformably overlies the Heavitree Quartzite, has been dated via Stromatolites as Late Riphaen (i.e. 650-930 m.y. (Walter, 1972)).|16-MAY-23
17944|Temple Bar Sandstone Member|Proposed publication|Stewart & others (in preparation); Clarke in Wells, 1976 p.26.|16-MAY-23
17944|Temple Bar Sandstone Member|Defn Reference|80/20787|16-MAY-23
17944|Temple Bar Sandstone Member|Resdate|1970|16-MAY-23
84110|Ten Mile Creek Member|Name source|Unit name derived from Ten Mile Creek, which rises at approximately (GDA94) 18°39’19”S 136°48’19”E in the west MOUNT DRUMMOND 1:250 000 mapsheet area, Northern Territory.|
84110|Ten Mile Creek Member|Unit history|Unit was originally mapped as an undivided part of the “Constance Sandstone” on the First Edition MOUNT DRUMMOND 1:250 000 mapsheet (Smith and Roberts, 1963a, b) and subsequently remapped as part of the “Top Lily Sandstone Member” of the “Playford Sandstone” on the Second Edition MOUNT DRUMMOND 1:250 000 mapsheet by Rawlings et al (2008). The “Playford Sandstone” outcrops north of the Mitchiebo-Maloney fault have been renamed the "Fish Hole Formation" and the “Ten Mile Creek Member” is part of this unit.|
84110|Ten Mile Creek Member|Geomorphic expression|The unit outcrops as a series of low ridges and plateaux.|
84110|Ten Mile Creek Member|Type section locality|There is no type locality nominated for this member. A reference area is nominated in the western MOUNT DRUMMOND 1:250 000 mapsheet, in the vicinity of (GDA94) latitude 18°40’S longitude 136°45’E (53K 684574mE 7935152mN).|
84110|Ten Mile Creek Member|Extent|Unit occurs in the southwestern portion of the MOUNT DRUMMOND 1:250 000 mapsheet in the Northern Territory [north of the Mitchiebo-Maloney fault].|
84110|Ten Mile Creek Member|Lithology|White to pink/dark pink-red, thickly to very thickly bedded, very fine- to fine-grained, well-sorted lithic sandstone; scattered granules and pebbles, trough cross-bedded on large scale, current ripples and primary current lineations common (Rawlings et al, 2008).[|
84110|Ten Mile Creek Member|Depositional environment|Unit is interpreted as depositing across a shallow-marine shelf environment (Rawlings et al, 2008).|
84110|Ten Mile Creek Member|Relationships and boundaries|The Ten Mile Creek Member (upper member of Fish Hole Sandstone) conformably overlies the lower Waterfall Member (previously [included in] the Wangalingi Member of the Playford Sandstone in Rawlings et al 2008), of the Fish Hole Formation.|
84110|Ten Mile Creek Member|Identifying features|Gossanous weathering crusts in places, due to its highly ferruginous and manganiferous nature (Rawlings et al, 2008).|
84110|Ten Mile Creek Member|Age reasons|Maximum depositional age derived from U-Pb SHRIMP dating of detrital zircons:
Waterfall Member (formerly Wangalinji Member) of the Fish Hole Formation (formerly the Playford Sandstone) (stratigraphically underlies the Ten Mile Creek Member): GA Sample 2785614 – 1600 ± 20 Ma (Kositcin and Carson, 2019). Ten Mile Creek Member: GA sample 2786167 – 1656 ± 12 Ma (Kositcin and Carson, 2019). Ten Mile Creek Member: GA Sample 3305196 - 1641 ± 14 Ma (Kositcin et al, 2020). Therefore, the potential depositional age range for the Ten Mile Creek Member can be considered to extend from ca. 1656 ± 12 Ma to 1600 ± 20 Ma.|
84110|Ten Mile Creek Member|Correlations|The Ten Mile Creek Member, based on similar maximum depositional age estimates with other units, can be correlated with the ungrouped Caulfield Formation and several other formations of the McNamara Group, including the Shady Bore Quartzite, the Bullrush Conglomerate and the Plain Creek Formation (Kositcin and Carson, 2019). The Ten Mile Creek Member may be correlative with components of the upper Glyde package to the lowermost Favenc package (Rawlings, 1999) of the McArthur Basin.|
84110|Ten Mile Creek Member|Alteration and Mineralisation|Ferruginised and silicified in places (Rawlings et al, 2008).|
84110|Ten Mile Creek Member|Geophysical Expression|Moderate magnetic response, likely due to the sandstone formations possessing “subtle magnetic layering” due to a high sedimentary iron content (Rawlings et al, 2008).|
84110|Ten Mile Creek Member|Defn author|Elliot Foley, Jack Simmons, Ben Williams, Charles Verdel (Northern Territory Geological Survey), Chris Carson (Geoscience Australia) 03-JAN-2023.|
84110|Ten Mile Creek Member|Comments|Note:. Standard series 1: 100 000 and 1: 250 000 mapsheet names are shown in uppercase.|
84110|Ten Mile Creek Member|References|Carson, C. J., Kositcin, N., Anderson, J. R., and Henson, P. A. in prep. A revised Proterozoic tectono-stratigraphy of the South Nicholson region, Northern Territory, Australia - insights from SHRIMP U-Pb detrital zircon geochronology. Australian Journal of Earth Sciences.
Kositcin N and Carson CJ, 2019. New SHRIMP U-Pb zircon ages from the South Nicholson and Carrara Range regions, Northern Territory. Geoscience Australia, Record 2019/09.  **Kositcin N, Carson CJ, Anderson JR, Doublier MP and Murr J, 2020. Exploring for the Future - New SHRIMP geochronology constraints on the basin evolution of the South Nicholson region. Geoscience Australia, Record 2020/025.  **Rawlings DJ, 1999. Stratigraphic resolution of a multiphase intracratonic basin system: the McArthur Basin, northern Australia. Australian Journal of Earth Sciences 46(5), 703-723.  **Rawlings DJ, Sweet IP and Kruse PD, 2008. Mount Drummond, NT (Second Edition). 1:250 000 Geological Map Series Explanatory Notes, Sheet SE 53-12. Northern Territory Geological Survey, Darwin, Northern Territory.  **Simmons JM, Williams B, Carson, C and Verdel C, 2023a. Mount Drummond, Northern Territory 1:250 000 Geological Map, Sheet SE 53-12 (Third Edition). Northern Territory Geological Survey, Darwin, Northern Territory.  **Simmons JM, Williams B, Carson, C and Verdel C, 2023b. Mount Drummond, Northern Territory 1:250 000 Geological Map Explanatory Notes, Sheet SE 53-12 (Third Edition). Northern Territory Geological Survey, Darwin, Northern Territory.  **Smith JW and Roberts HG, 1963a. Mount Drummond, NT (First Edition). 1:250 000 Geological Map Series Explanatory Notes, Sheet 53-12. Bureau of Mineral Resources, Canberra.  **Smith JW and Roberts HG, 1963b. Mount Drummond, NT (First Edition). 1:250 000 Geological Map Series, Sheet SE 53-12. Bureau of Mineral Resources, Canberra.|
18039|The Granites Granite|Name source|The Granites, an abandoned gold-mining settlement at latitude 20o33'30"S, longitude 129o21'30"E, in The Granites Sheet area, SF/52-3.|16-MAY-23
18039|The Granites Granite|Type section locality|Prominent tors and groups of spheroidal boulders 1 km S of The Granites, at latitude 20o34'30"S, longitude 129o21'10"E. These are formed of grey, medium to fine-grained biotite adamellite containing variable amounts of quartz and feldspar phenocrysts and dark fine-grained xenoliths.|16-MAY-23
18039|The Granites Granite|Extent|Scattered outcrops in the eastern part of The Granites Sheet area and on western margin of adjoining Mount Solitaire Sheet area.|16-MAY-23
18039|The Granites Granite|Lithology|Pink and grey porphyritic and non porphyritic biotite adamellite; minor pegmatite and aplite; locally foliated.|16-MAY-23
18039|The Granites Granite|Relationships and boundaries|Intrudes low grade metamorphics of the Mount Charles Beds, part of the Archaean? Tanami complex (Blake et al., in press). Overlian by Carpentarian Gardiner Sandstone (Blake et al., in press) and Adelaidean Muriel Range Sandstone (Blake & Hodgson, in prep.).|16-MAY-23
18039|The Granites Granite|Age reasons|Dated isotopically by R W Page, using the whole rock Rb-Sr method, at 1780 +/- 24 m.y.,i.e. early Carpentarian.|16-MAY-23
18039|The Granites Granite|Proposed publication|BMR Report|16-MAY-23
18039|The Granites Granite|Name first published by|Page R.W., Blake LD.H., Mahon M.W., 1976|16-MAY-23
80338|Thring Granite|Name source|After Thring Creek (606500 mE 7476200 mN, GDA94, Zone53) in Jervois Range 1:100 000 map sheet, Northern Territory.|16-MAY-23
80338|Thring Granite|Unit history|Previously Mascotte Gneiss Complex (pCm) on the second edition Huckitta 1:250 000 map sheet (Freeman et al 1986).|16-MAY-23
80338|Thring Granite|Geomorphic expression|Irregular, sharp-crested hills and bouldery outcrops in lowlands between hills.|16-MAY-23
80338|Thring Granite|Type section locality|611792mE 7480508mN (GDA94, Zone53), approximately 7 km northeast of Mount Thring.|16-MAY-23
80338|Thring Granite|Extent|Extensive outcrop over an area of approximately 150 km2 in the Bonya Hills region, western Jervois Range 1:100 000 map sheet.|16-MAY-23
80338|Thring Granite|General description|Locally fine-grained and biotite-free, locally rottenstone.|16-MAY-23
80338|Thring Granite|Lithology|Granite; strongly weathered, leucocratic, homogenous, medium- to coarse-grained equigranular quartz-K-feldspar-plagioclase-biotite. Minor biotite variably altered to chlorite. Foliated.|16-MAY-23
80338|Thring Granite|Depositional environment|Continental margin environment, either arc cordillera, back arc basin, or derived from melting of pre-existing crust that formed in a continental margin environment.|16-MAY-23
80338|Thring Granite|Relationships and boundaries|Contact relationships with country rock units generally not observed, but occurs spatially with Mascotte Orthogneiss, White Violet Orthogneiss, Kings Legend Metadolerite and Bonya Metamorphics and is interpreted to intrude some or all of these units. Intruded by tourmaline-bearing dykes of the Samarkand Pegmatite and garnet-bearing aplite dykes of unknown origin. Exact nature of unit boundaries is not possible to define due to later tectonism and Cenozoic cover. Locally faulted contacts with Kings Legend Metadolerite and Mascotte Orthogneiss; unconformably overlain by Oorabra Arkose, Elkera Formation and Mount Baldwin Formation of the Georgina Basin.|16-MAY-23
80338|Thring Granite|Identifying features|Strongly leucocratic.|16-MAY-23
80338|Thring Granite|Structure and Metamorphism|Penetrative grain shape foliation that is weakly- to well-developed and defined by aligned biotite (or chlorite) and elongate quartz. Weak to moderate gneissic banding locally developed. Intruded prior to regional high-temperature and low-pressure peak amphibolite facies metamorphism.|16-MAY-23
80338|Thring Granite|Age reasons|Interpreted to be synchronous with intrusion of 1780 ± 4 Ma Jericho Granite (LA-ICP-MS 207Pb/206Pb, Beyer et al in prep).|16-MAY-23
80338|Thring Granite|Correlations|Interpreted as co-magmatic and co-genetic with Jericho and Unca granites of the Fosters Suite, Baikal Supersuite based on similar geochemical and isotopic composition, and timing of structural fabric development.|16-MAY-23
80338|Thring Granite|Alteration and Mineralisation|Strongly bleached, silicified and locally hematite-altered. Brecciated in outcrops that are crosscut by large-scale quartz veins and also in contact zones with unconformably overlying Georgina Basin stratigraphy; local carbonate veining; no known mineralisation.|16-MAY-23
80338|Thring Granite|Geophysical Expression|Magnetic low signal including a circular magnetic-high body with circular linear high-trends and contact aureole.|16-MAY-23
80338|Thring Granite|Geochemistry|Moderately to strongly peraluminous I-type monzogranite and syenogranite.|16-MAY-23
80338|Thring Granite|Defn author|Anett Weisheit, Barry Reno, Eloise Beyer (Northern Territory Geological Survey) 29-JUN-2019.|16-MAY-23
80338|Thring Granite|Proposed publication|Weisheit A, Reno BL and Beyer EE, in review. Jervois Range Special, Northern Territory. 1:100 000 geological map explanatory notes, 6152 and part 6252. Northern Territory Geological Survey, Darwin.|16-MAY-23
80338|Thring Granite|References|Beyer EE, Reno BL, Weisheit A, Whelan JA, Thompson JM, Meffre S and Woodhead JD, 2018. Summary of results. NTGS laser ablation ICP-MS U-Pb-Hf geochronology project: selected samples from JERVOIS RANGE 1:100 000 and TOBERMOREY 1:250 000 mapsheets, Aileron and Irindina provinces, January 2014 - December 2016. Northern Territory Geological Survey, Record 2018-001.  **Beyer EE, Reno BL, Weisheit A, Meffre S, Thompson J and Woodhead JD, in prep. Summary of results. NTGS laser ablation ICP¿MS U-Pb-Hf geochronology project: selected samples from JINKA and JERVOIS RANGE 1:100 000 mapsheet areas, Aileron and Irindina Provinces, Arunta Region, March 2015 - December 2017. Northern Territory Geological Survey, Darwin.  **Freeman MJ, Black LA, Offe LA, Senior BR, Shaw RD, Shergold JH, Simpson CJ, Walter MR, Warren RG, Donnellan N, Horsfall CJ, Laurie JR and Walley AM, 1986. Huckitta, Northern Territory (Second Edition). 1:250 000 geological map series, SF 53-11. Northern Territory Geological Survey, Darwin|16-MAY-23
18189|Tin Camp Granite|Name source|Tin Camp Creek 133o10'E 12o25'S. Alligator River 1:250 000 Sheet area.|16-MAY-23
18189|Tin Camp Granite|Type section locality|Extensive pavement exposure on east bank of main southern tributary of Tin Camp Creek, in northeast part of Caramal East Inlier, 5 km ENE of Caramal prospect, 133o24'E 12o29'30"S. Altered massive medium grained pink biotite granite cut by quartz breccia reefs.|16-MAY-23
18189|Tin Camp Granite|Extent|Two areas of outcrop each approx. 4 km2 in the vicinity of the headwaters of Tin Camp Creek. One area of exposure approx. 20 km2 centred 15 km ESE of Beatrice prospect. Areas delineated on 1:250 000 geological map (special) accompanying environmental fact finding study report. Bur. Miner. Resour. Aust. Rec. 1973/208 by Needham R.S., Wilkes P.G., Smart P.G., Watchman A.L.|16-MAY-23
18189|Tin Camp Granite|Lithology|Altered pink biotite granite, strongly altered to a quartz-clay rock with brown iron oxides. Transected by aplite dykes altered to quartz, sericite-clay rocks, and by approximately north-trending quartz breccias, which often form ridges. Radioactive background is generally x10 that of Nimburwah Complex.|16-MAY-23
18189|Tin Camp Granite|Relationships and boundaries|Intrudes Nimburwah Complex, unconformably overlain by Carpentarian Kombolgie Formation. Contact effects apparently masked by alteration effects. Petrologically similar to, and most probably genetically associated with, the Nabarlek Granite.|16-MAY-23
18189|Tin Camp Granite|Age reasons|Approx. 1800 m.y. (Page & Needham, in prep.). Age to be viewed with caution due to altered nature of material used.|16-MAY-23
18189|Tin Camp Granite|Defn author|Needham R.S., Stuart-Smith P.G., 1976.|16-MAY-23
18189|Tin Camp Granite|Proposed publication|Journal of the Geological Society of Australia|16-MAY-23
24525|Tindall Limestone|Name source|Tindall Aerodrome, 11 km southeast of Katherine (Manbulloo 1:100 000).|16-MAY-23
24525|Tindall Limestone|Unit history|Elliott Creek Formation of Noakes (1949) in part; Tipperary Limestone of Walpole (1958) in part.|16-MAY-23
24525|Tindall Limestone|Geomorphic expression|Flat to undulating plains with isolated residuals; variety of karst features including towers, pavements and dolines.|16-MAY-23
24525|Tindall Limestone|Type section locality|579.3 - 760.0 m in cored drillhole NTGS 86/1, northeastern Jinduckin 1:100 0000, AMG587327 (latitude 14o09'50"S, longitude 131o23'50"E). Core stored at NTGS Core Library, Darwin.|16-MAY-23
24525|Tindall Limestone|Extent|Outcrop in Pine Creek, Fergusson River, Katherine, Delamere, Larrimah 1:250 000; subcrop proven or inferred in Cape Scott, Hodgson Downs, Dly Waters, Tanumbirini 1:250 000.|16-MAY-23
24525|Tindall Limestone|Thickness range|Maximum 182.8 m in corehole CCVH1 (Manbulloo 1:100 0000);180.7 m in type section.|16-MAY-23
24525|Tindall Limestone|Lithology|Light grey-brown partially dolomitised limestone with silt laminations and stylolites, two-tone limestone (interbeds of light grey pure calcilutite and dark grey marl), bioclastic limestone, dark grey mudstone, maroon-green siltstone, minor stromatolitic boundstone and cryptalgal laminate, basal maroon siltstone in type section. Elsewhere there are mottled limestones (lateral equivalent of two-tone limestone), onkoid limestones, local megabreccias in Tipperary 1:100 000 and bioclastic calcarenites in Katherine 1:100 000. Basal lithology is generally maroon siltstone, but around Fenton Granite in Tipperary 1:100 0000 and Mount Litchfield Granite in Reynolds River 1:100 000 it is maroon-purple arkosic sandstone and conglomerate.|16-MAY-23
24525|Tindall Limestone|Relationships and boundaries|In type section: unconformable on Early Proterozoic quartz-mica schist below, apparent conformity with Jinduckin Formation above. Elsewhere: rests unconformably on various units of Pine Creek Orogen, Victoria Basin and McArthur Basin, particularly the Antrim Plateau Volcanics and equivalents, Jindare Formatrion, Tolmer Group, Burrell Creek Formation, Welltree Metamorphics, Wagait and Fenton Granites and Cullen Granite Complex. Where not overlain by Jinduckin Formation, the unit is commonly unconformably overlain by Cretaceous sandstones (Petrel Formation, Bathurst Island Formation).  Upper boundary with Jinduckin Formation is placed at top of highest limestone in the sequence (partially dolomitised in places).|16-MAY-23
24525|Tindall Limestone|Structure and Metamorphism|Horizontal to very gently dipping.|16-MAY-23
24525|Tindall Limestone|Age reasons|Middle Cambrian, Ordian, based on trilobites Redlichia and Xystridura, ptychopariid trilobites, hyoliths, brachiopods, monoplacophoran molluscs and sponges (Opik, 1956; Opik in Walpole and others, 1968; Shergold and others, 1985).|16-MAY-23
24525|Tindall Limestone|Correlations|Lateral equivalent of upper Montejinni Limestone (Wiso Basin) and correlative with Merrina Beds (Wiso Basin), Gum Ridge Formation (Georgina Basin) and Top Springs Limestone (McArthur Basin), and in part with Panton Formation (Ord Basin).|16-MAY-23
24525|Tindall Limestone|Proposed publication|Tipperary 1:100 000 explanatory notes.  NTGS.|16-MAY-23
24525|Tindall Limestone|Comments|Updated xx     B13|16-MAY-23
24525|Tindall Limestone|References|B016; 01/31591; B037; B082.|16-MAY-23
24525|Tindall Limestone|Defn approved by|Kruse P.D.; originally Randal (1962), Malone (1962)|16-MAY-23
24525|Tindall Limestone|First Reference|79/02662|16-MAY-23
24525|Tindall Limestone|Proposer|Kruse P.D.; originally Randal (1962), Malone (1962)|16-MAY-23
24525|Tindall Limestone|Resdate|24-APR-1988|16-MAY-23
24525|Tindall Limestone|Status|1|16-MAY-23
24526|Tinfish Sandstone|Name source|Tinfish Well (AMG GR LR836665) in the Barrow 1:100 000 sheet (5654).|16-MAY-23
24526|Tinfish Sandstone|Unit history|Originally mapped as undifferentiated Arunta Block (Smith and Milligan, 1964).|16-MAY-23
24526|Tinfish Sandstone|Geomorphic expression|Low rounded strike ridges with pale to medium airphoto tones.|16-MAY-23
24526|Tinfish Sandstone|Type section locality|In the northwestern part of Taylor 1:100 0000 sheet; base at AMG GR LS982590 (latitude 21o10'03"S, longitude 134o01'10"E); top at GR LS984590 (latitude 21o10'03"S, longitude 134o01'17"E).|16-MAY-23
24526|Tinfish Sandstone|Extent|Near the northeastern end of the Osborne Range on the Taylor (5755) and Crawford (5655) 1:100 000 sheets.|16-MAY-23
24526|Tinfish Sandstone|Thickness range|About 400 m at the type section|16-MAY-23
24526|Tinfish Sandstone|Lithology|(in decreasing order of abundance): Arenite: fine- to coarse-grained, feldspathic and poorly sorted, friable, micaceous, with scattered quartz arenite pebbles and cobbles, ridge-forming: Quartz arenite: iron-stained, fine- to medium-grained, thinly to thickly bedded, slightly micaceous in places, ridge-forming; Feldspathic, quartz-biotite schist, recessive.|16-MAY-23
24526|Tinfish Sandstone|Relationships and boundaries|Conformably overlies and interfingers with the Strzeleckie Volcanics. Sharply and probably disconformably overlain by the Illoquara Sandstone. The Tinfish Sandstone is contemporaneous or penecontemporaneous with the Strzeleckie Volcanics. A lens of the Tinfish Sandstone in the Strzeleckie Volcanics is present at AMG GR LS967582. Included in the Wauchope Subgroup of the Hatches Creek Group.|16-MAY-23
24526|Tinfish Sandstone|Identifying features|None given.|16-MAY-23
24526|Tinfish Sandstone|Structure and Metamorphism|Tightly to isoclinally folded, faulted.|16-MAY-23
24526|Tinfish Sandstone|Age reasons|The maximum age of the Hatches Creek Group is Early Proterozoic (Blake & others, 1987).|16-MAY-23
24526|Tinfish Sandstone|Correlations|Possibly correlates with Yeeradgi Sandstone (Blake and othes, 1985).|16-MAY-23
24526|Tinfish Sandstone|Defn author|Leon Bagas April 1990|16-MAY-23
24526|Tinfish Sandstone|Proposed publication|Barrow Creek 1:250 000 Geol. Series, Explan. Notes, NT Geological Survey|16-MAY-23
24526|Tinfish Sandstone|Comments|Possibly deposited in a fluvial environment during contemporaneous or penecontemporaneous volcanism.|16-MAY-23
24526|Tinfish Sandstone|References|Blake, D.H.,  Stewart, A.J.,  Sweet, I.P.,  Wyche, S. 1985. Definitions of newly named and revised Precambrian rock units in the Davenport and Murchison Ranges of central Australia (Northern Territory). BMR report 257.*** Blake, D.H.,  Stewart, A.J.,  Sweet, I.P., Hone, I. G., 1987. Geology of the Proterozoic Davenport Province, central Australia. BMR Bulletin 226.***Smith, K. G., Milligan, E.N. 1964. Barrow Creek, Northern Territory; 1:250 000 geological series. BMR Explanatory Notes SF53-6.|16-MAY-23
24526|Tinfish Sandstone|Category|2|16-MAY-23
36772|Tjauwata Group|Name source|Tjauwata Outstation at location 24o 54' 54.25" S, 129o 07' 55.94" E (WGS 84).|16-MAY-23
36772|Tjauwata Group|Unit history|Lower section equivalent to Bloods Range beds of Forman (1966).|16-MAY-23
36772|Tjauwata Group|Constituents|Karukali Quartzite, Tjuninanta Formation, Mount Harris Basalt, Puntitjata Rhyolite, Bloods Range Formation.|16-MAY-23
36772|Tjauwata Group|Geomorphic expression|Low hills and footslopes below scarps of strike ridges of Dean Quartzite and Kulail Sandstone.|16-MAY-23
36772|Tjauwata Group|Type section locality|Type localities for the constituent units are given in their respective formal definitions.|16-MAY-23
36772|Tjauwata Group|Extent|Central Hull and Bloods Range 1:100 000 mapsheets- south of Bloods and Rowley Ranges, north of Ilyaralona Range and the Mount Berteaux region, Petermann Ranges 1:250 000 mapsheet. Extends west into WA on southern Rawlinson 1:250 000 mapsheet and northeastern Scott 1:250 000 mapsheet.|16-MAY-23
36772|Tjauwata Group|Thickness range|Greater than 1 km - maximum thickness unknown due to discontinuous outcrop and structural thickening.|16-MAY-23
36772|Tjauwata Group|Lithology|Basal conglomeratic quartzite overlain by interlensed silicified, epidotised amygdaloidal metabasalt, quartzite, quartz-muscovite schist, dark grey phyllitic schist and felsic volcaniclastics. Variably silicified and epidotised amygdaloidal metabasalt with minor quartzite, metamorphosed porphyritic rhyolite and polymict pebble conglomerate, quartzite-cobble conglomerate, immature sandstone, red and dark fine grained sandstone and siltstone, epiclastic and volcaniclastic rocks, rare tuffs.|16-MAY-23
36772|Tjauwata Group|Depositional environment|Subaqueous, initially a shoreline depositional setting, then deepening to alluvial and fluvial environment. Limited evidence suggests initial basalt flows were deposited in a subaqueous environment.|16-MAY-23
36772|Tjauwata Group|Relationships and boundaries|Unconformably overlies undivided Pottoyu Granite suite. Disconformably overlain by basal sediments of the Amadeus Basin (Kulail Sandstone and Dean Quartzite).|16-MAY-23
36772|Tjauwata Group|Age reasons|Meso-Neoproterozoic. Younger than 1190-1150 Ma Pottoyu Granite Suite and older than the ~850 Ma Dean Quartzite. The Puntitjata Rhyolite lies within the upper stratigraphy of the Tjauwata Group and is dated at 1075 +/- 2 Ma. Shallow level granites such as the Rowley Granophyre and the Walu Granite intrude the middle stratigraphic section of the Tjauwata Group and are dated at 1075 +/- 2 Ma and 1084 +/- 9 Ma respectively.|16-MAY-23
36772|Tjauwata Group|Correlations|The Tjauwata Group probably correlates with unnamed quartzite, basal conglomerate, sheared porphyry, quartz-feldspar porphyry, sheared basalt, quartz sericite schist on the adjacent Rawlinson and Scott 1:250 000 mapsheets in WA. Correlated with the Tollu Group of the Bentley Supergroup in western Musgrave Block (after Daniels 1974).|16-MAY-23
36772|Tjauwata Group|Proposed publication|Close, D.F., Edgoose, C.J., Scrimgeour, I.R., 2002. Bloods Range and Hull 1:100 000 geological special, Northern Territory Geological Survey, Explanatory notes.|16-MAY-23
36772|Tjauwata Group|Comments|Thrust repetition within the Tjauwata Group, as a result of the 570-520 Ma Petermann Orogeny, has led to difficulties in determining precise stratigraphic relationships and true thickness of the sequence.|16-MAY-23
36772|Tjauwata Group|References|79/01069 - Daniels J.L., 1974, The geology of the Blackstone region, Western Australia. Geological Survey of Western Australia. Bulletin, 123.|16-MAY-23
41853|Tjungkubu Granodiorite|Name source|Tjungkubu Hills 23o 11' 00" S, 131o 02' 00" E, MOUNT LIEBIG.|16-MAY-23
41853|Tjungkubu Granodiorite|Unit history|Previously included within undifferentiated gneiss, schist, amphibolite, quartzite, granite, dolerite and pegmatite of the Arunta Complex  (Ranford 1969)|16-MAY-23
41853|Tjungkubu Granodiorite|Geomorphic expression|Prominent, often steep-sided hills with bouldery outcrop|16-MAY-23
41853|Tjungkubu Granodiorite|Type section locality|(WGS 84). 2 km southwest of Tjungkubu Hills at 23o 11' 48.9" S, 131o 00' 40.3" E, MOUNT LIEBIG.|16-MAY-23
41853|Tjungkubu Granodiorite|Description at type locality|Medium to fine grained equigranular hornblende-biotite granodiorite with discontinuous diffuse leucosomes that are sheared with leucosomes forming in shear zones. The granodiotite has a weak to moderate foliation.|16-MAY-23
41853|Tjungkubu Granodiorite|Extent|In Tjungkubu Hills and in scattered hills extending up to 10km to the east and west, MOUNT LIEBIG.|16-MAY-23
41853|Tjungkubu Granodiorite|Lithology|Foliated, equigranular to weakly porphyritic, variably migmatitic biotite-hornblende granodiorite. It commonly contains discontinuous hornblende-bearing leucosomes that are interpreted to reflect incipient partial melting and less commonly  is migmatitic with a gneissic layering defined by parallel hornblende-bearing leucosomes. The mineral assemblage typically comprises biotite, hornblende, titanite, Fe-Ti oxides, plagioclase, quartz and K-feldspar.|16-MAY-23
41853|Tjungkubu Granodiorite|Relationships and boundaries|Has intrusive contacts with Talyi-Talyi Charnockite, but no clear relative timing relationships.|16-MAY-23
41853|Tjungkubu Granodiorite|Age reasons|late Palaeoproterozoic. Geochemically related to Talyi-Talyi Charnockite, which has a SHRIMP U-Pb zircon age of 1631 +/- 4 Ma (Cross et al 2003).|16-MAY-23
41853|Tjungkubu Granodiorite|Correlations|Strong geochemical affinity with other granites of the Waluwiya Suite ? Larrie Granodiorite, Kakalyi Gneiss, Talyi-Talyi Charnockite and Russell Charnockite.|16-MAY-23
41853|Tjungkubu Granodiorite|Comments|Deformed and metamorphosed at upper amphibolite facies conditions during the 1590-1560 Ma Chewings Orogeny.|16-MAY-23
41853|Tjungkubu Granodiorite|References|Cross A, Claoue-Long J, Scrimgeour IR, Close DF & Edgoose CJ, in prep. NTGS-GA Geochronology project, Report 6. Northern Territory Geological Survey, Record. **Ranford LC, 1969. Mount Liebig, Northern Territory (First Edition). 1:250 000 geological map series explanatory notes, SF52-16. Bureau of Mineral Resources, Australia. **Scrimgeour IR, Close DF & Edgoose CJ, in prep. Mount Liebig, Northern Territory (Second Edition) 1:250 000 geological map series explanatory notes, SE 52-16. Northern Territory Geological Survey, Darwin.|16-MAY-23
41853|Tjungkubu Granodiorite|Parent|Waluwiya Suite|16-MAY-23
36773|Tjuninanta Formation|Name source|Tjuninanta Outstation, south central Hull 1:100 000 mapsheet, at location 24o 51' 07.86" S, 129o 13' 50.25" E (WGS 84)|16-MAY-23
36773|Tjuninanta Formation|Unit history|Formerly part of Bloods Range Beds and Mount Harris Basalt from BMR first edition mapping (Forman 1966).|16-MAY-23
36773|Tjuninanta Formation|Constituents|None named, but has been divided into three informal lithotypes: 1) silicified, epidotised metabasalt, 2) quartzite, quartz muscovite schist, phyllitic schist, 3) volcaniclastics.|16-MAY-23
36773|Tjuninanta Formation|Geomorphic expression|Low to medium ridges and low hills.|16-MAY-23
36773|Tjuninanta Formation|Type section locality|Type locality: amygdaloidal basalt - 24o 47' 47.13" S, 129o 30' 09.32" E (WGS 84). Reference locality: quartz sandstones and grey phyllite - 24o 48' 12.67" S, 129o 32' 24.78" E (WGS 84). Reference locality: volcaniclastics - 24o 51' 23.69" S, 129o 28' 19.74" E (WGS 84).|16-MAY-23
36773|Tjuninanta Formation|Extent|East central Hull and central Bloods Range 1:100 000 mapsheets|16-MAY-23
36773|Tjuninanta Formation|Thickness range|The sequence is structurally repeated and therefore thickness is not known.|16-MAY-23
36773|Tjuninanta Formation|Lithology|Basalt, volcaniclastics/felsic volcanics, quartz sandstone, quartzite, phyllite, rare diagenetic chert|16-MAY-23
36773|Tjuninanta Formation|Depositional environment|Includes extrusive rocks and intercalated sediments deposited in shallow marine, fluvial and lacustrine environments.|16-MAY-23
36773|Tjuninanta Formation|Relationships and boundaries|Overlain by Mount Harris Basalt, gradational contact. Conformably overlies Karukali Quartzite.|16-MAY-23
36773|Tjuninanta Formation|Age reasons|Mesoproterozoic. The extrusive components are interpreted to be co-magmatic with Mount Harris Basalt and the Puntitjata Rhyolite (1075+/- 2.5 Ma).|16-MAY-23
36773|Tjuninanta Formation|Correlations|Potential correlatives are unnamed sediments within volcanic sequences in adjoining parts of WA (Horwitz and Daniels 1966, Daniels 1974, Forman 1966).|16-MAY-23
36773|Tjuninanta Formation|Proposed publication|Close, D.F., Edgoose, C.J., Scrimgeour, I.R., 2002. Bloods Range and Hull 1:100 000 geological special, Northern Territory Geological Survey, Explanatory notes.|16-MAY-23
36773|Tjuninanta Formation|Comments|Formerly mapped as Bloods Range beds, Mount Harris Basalt, and unnamed porphyry (Forman, 1966). The basalt is equivalent to the Mount Harris Basalt, but has been separated out because it is interbedded with felsic volcaniclastic rocks and sediments. Forms part of the newly defined Tjauwata Group.|16-MAY-23
36773|Tjuninanta Formation|References|98/29502 - Forman, D.J., 1966. Bloods Range Northern Territory 1:250 000 geological series explanatory notes. Sheet (SG53-3). Bureau of Mineral Resources, Australia. **Horwitz, R.C. and Daniels, J.L., 1966. A late Precambrian belt of vulcanicity in central Australia. W. A. Geological Survey Annual Report/Review. **79/01069 - Daniels J.L., 1974, The geology of the Blackstone region, Western Australia. Geological Survey of Western Australia. Bulletin, 123.|16-MAY-23
37740|Tobacco Member|Name source|Tobacco Waterhole along Playford River at eastern end of Mittiebah Range, southern MOUNT DRUMMOND, near 18o53'S, 137o5'E.|16-MAY-23
37740|Tobacco Member|Unit history|Encompasses narrow strip of moderately resistant outcrop at northern edge of Mittiebah Range that was formerly mapped as Mittiebah Sandstone by Smith and Roberts (1963) in First Edition MOUNT DRUMMOND. Also incorporates similar narrow strip of moderately resistant outcrop along Canyon Range that was formerly mapped as Mullera Formation.|16-MAY-23
37740|Tobacco Member|Geomorphic expression|Moderately resistant with well developed, banded white and dark brown phototones.|16-MAY-23
37740|Tobacco Member|Type section locality|Central Mittiebah Range at 18o50'S, 136o7'E in MOUNT DRUMMOND. Section extends from 687300mE 7916800mN (base) to 688100mE 7916100mN (top). In this area, Tobacco Member conformably overlies lower Crow Formation and is, in turn, conformably overlain by Mittiebah Sandstone. However, base is not exposed in type section, so lower boundary stratotype proposed at eastern end of Mittiebah Range at 18°14'29"S, 136°52'49"E (698000mE 7917350mN)|16-MAY-23
37740|Tobacco Member|Extent|Canyon Range and Mittiebah Range in northwestern and southwestern MOUNT DRUMMOND, respectively|16-MAY-23
37740|Tobacco Member|Thickness range|300-600 m.|03-OCT-23
37740|Tobacco Member|Lithology|Dominant facies resistant (ridge-forming), shallow-water sandstone, with lesser recessive storm shelf facies. In type section, shallow-water sandstone facies comprises interbedded: (i) medium- to very thickly bedded, diffusely bedded, quartzose to lithic, locally ferruginous and micaceous (± glauconitic) fine ± medium-grained sandstone with amalgamated low-angle trough and hummocky cross-stratification; (ii) medium- to coarse-grained glauconitic sandstone, containing small red-brown mudstone flakes, pits after evaporites and trough cross-beds and; (iii) minor decimetre-scale beds of very coarse to granular, pebbly lithic sandstone with parallel lamination. Storm-shelf facies composed of flaggy white, fawn, red-brown or purple, micaceous siltstone and fine- to medium-grained quartzose to sublithic (± micaceous) sandstone. Sedimentary structures include wavy and lenticular bedding, hummocky cross-stratification, symmetric ripples, mudclasts, flute moulds, tool marks, current lineations, runzel marks, load casts and convolute bedding|03-OCT-23
37740|Tobacco Member|Relationships and boundaries|Of Crow Formation, Wild Cow Subgroup, South Nicholson Group. Lies conformably on lower Crow Formation and is, in turn, conformably overlain by Mittiebah Sandstone. Member not differentiated in areas where Crow Formation is overlain by Constance Sandstone.|16-MAY-23
37740|Tobacco Member|Age reasons|Maximum age of 1591 +/- 10 Ma, based on reworked tuffaceous material from underlying Lawn Hill Formation (Page et al 2000) in LAWN HILL, or 1595 +/- 6 Ma based on tuffs in Lawn Hill Formation in same area (Page and Sweet 1998). Interpreted age range of 1500-1400 Ma for South Nicholson Group based on correlation with Roper Group of southern McArthur Basin (Dunn et al 1966; Plumb and Derrick 1975). Ages of 1492 +/- 4 Ma and 1493 +/- 4 Ma for tuffaceous material from Mainoru Formation in lower Roper Group (Jackson et al 1999) provide the most reliable estimate for age of that group, and hence, for Crow Formation, including Tobacco Member.|16-MAY-23
37740|Tobacco Member|Defn author|Rawlings D.J. ~2005, published 2008.|16-MAY-23
37740|Tobacco Member|References|**DUNN P.R., Plumb K.A. and Roberts H.G. 1966. A proposal for time-stratigraphic subdivision of the Australian Precambrian. Journal of the Geological Society of Australia, 13, 593¿608.  **JACKSON M.J., Sweet I.P., Page R.W. and Bradshaw B.E., 1999. The South Nicholson and Roper Groups: evidence for the early Proterozoic Roper Superbasin. In: Bradshaw B.E. and Scott D.L. (Eds.), Integrated basin analysis of the Isa Superbasin using seismic, well-log and geopotential data: an evaluation of the economic potential of the northern Lawn Hill Platform. Australian Geological Survey Organisation, Record 1999/19 (unpaginated).   **PAGE R.W., Jackson M.J. and Krassay A.A., 2000. Constraining sequence stratigraphy in north Australian basins: SHRIMP U-Pb zircon geochronology between Mt Isa and McArthur River. Australian Journal of Earth Sciences, 47, 3; 431-459.  **PAGE R.W. and Sweet I.P., 1998. Geochronology of basin phases in the western Mount Isa Inlier, and correlation with the McArthur Basin. Australian Journal of Earth Sciences, 45, 2; 219-232.   **PLUMB K.A. and Derrick G.M., 1975. Geology of the Proterozoic rocks of the Kimberley to Mount Isa Region. In Knight C.L. (Editor), Economic Geology of Australia and Papua New Guinea, 1. Metals. The Australasian Institute of Mining and Metallurgy, Monograph Series, 5, 217¿252.   **SMITH J.W. and Roberts H.G., 1963. Mount Drummond, N.T. (First Edition); 1:250,000 geological series, sheet SE53-12. Bureau of Mineral Resources, Geology and Geophysics, Map and Explanatory Notes.|16-MAY-23
27070|Tollis Formation|Name source|Tollis Reef 9 Katherine and Edith River Region 1:100 000 Sheet areas) GR 877346.|16-MAY-23
27070|Tollis Formation|Unit history|Mapped previously as part of the Burrell Creek Formation by Walpole & others, 1968.|16-MAY-23
27070|Tollis Formation|Type section locality|Between the ruins of the Mount Todd Battery (Katherine GR 875318) and a point 4 km to the southeast. A conformable, steeply dipping folded sequence comprising of three subunits the lower about 740 m interbedded greywacke, pink tuffaceous greywacke, siltstone, pale green argillite, cherty tuff, overlain by about 590 to 900 m of interbedded pale green argillite, spotted crystal tuff, greywacke, tuffaceous greywacke and siltstone overlain by about 850 m of interbedded phyllite, argillite, greywacke and crystal tuff. Base is taken as lowermost volcanic bed where unconformable contact is obscure. Sequence continues to axis of basinal synform, i.e. top not exposed.  Refrence section: Banks of Phillips Creek between Katherine GRs 924278, 932263. Northwest-dipping 1280 m thick sequence which at 932263 is overlain unconformably by the Phillips Creek Sandstone of the Edith River Group.|16-MAY-23
27070|Tollis Formation|Extent|Exposed extensively within a 5000 km2 area in the Katherine region, between Mount Todd and Bamyili, and Katherine and Grace Creek.|16-MAY-23
27070|Tollis Formation|Thickness range|<2200 m. Sub-units recognisable only NW of Katherine; elsewhere unit has characteristics of the lower sub-units.|16-MAY-23
27070|Tollis Formation|Lithology|As listed for type section, plus minor ignimbrite in Phillips Creek area, minor volcanic agglomerate and carbonate breccia northeast of Katherine, in road cuttings on the gorge road.|16-MAY-23
27070|Tollis Formation|Relationships and boundaries|Angular unconformity on Burrell Creek Formation of Early Proterozoic Finniss River Group. Overlain unconformably by units of the Edith River Group and Kombolgie Formation. Uppermost unit of El Sherana Group and its only representative in the Mt Todd-Bamyili area; correlative of Big Sunday Formation in South Alligator Valley.|16-MAY-23
27070|Tollis Formation|Age reasons|Older than the 1730-1780 m.y. granite (Page & others, 1980, Riley, 1980) deduced from hornfelsed units of the same group in the South Alligator Valley (Pul Pul Rhyolite hornfelsed by Malone Creek Granite). Younger than the 1800 m.y. (R W Page, pers. comm. 1983) Early Proterozoic geosynclinal sediment sequence; therefore late Early Proterozoic, 1800-1730 m.y.|16-MAY-23
27070|Tollis Formation|Proposed publication|Map commentary Edith River Region 1:100 000 Sheet.|16-MAY-23
27070|Tollis Formation|Proposer|Needham S.|16-MAY-23
68748|Top Lily Sandstone Member|Name source|From Top Lily Waterhole, in Fish Hole Creek at Latitude 18o26'S longitude 136o53'E, in MOUNT DRUMMOND.|16-MAY-23
68748|Top Lily Sandstone Member|Unit history|Previously mapped as Constance Sandstone on the first edition of MOUNT DRUMMOND by Smith and Roberts (1963), and by Sweet (1984) on the Carrara Range Region 1:100 000 map.|16-MAY-23
68748|Top Lily Sandstone Member|Geomorphic expression|A series of low ridges and plateaux.|16-MAY-23
68748|Top Lily Sandstone Member|Type section locality|Upper part of the Playford Sandstone type section, 4 km southeast of Mitchiebo Waterhole, in MOUNT DRUMMOND. The section runs from south to north: base is at latitude 18o39'39"S longitude 137o7'29"E (724130E 7935360N), the top about 500 m to the north, at latitude 18o39'25"S longitude 137o7'33"E (724230E 7935810N). The locality is easily accessed from the Mittiebah homestead-Wangalinji track.|16-MAY-23
68748|Top Lily Sandstone Member|Extent|Forms a west to west-southwest-trending outcrop belt in central to southwestern MOUNT DRUMMOND, from the headwaters of Maloney Creek in the east, to Waterfall Creek in the southwest. Outcrops most extensively in ranges forming the watershed of Eight Mile, Ten Mile, and Waterfall Creeks. An isolated outcrop occurs in the northwest, east of the headwaters of Benmara Creek.|16-MAY-23
68748|Top Lily Sandstone Member|Thickness range|143 m thick in the type section, 750 m 17 km to the west-northwest, in the Playford Anticline, and 1100 m 40 km away in the westernmost outcrops of the Ten Mile Anticline.|16-MAY-23
68748|Top Lily Sandstone Member|Lithology|White to pink or darker pink-red, thick to very thick bedded, very fine- to fine-grained, well-sorted lithic sandstone; scattered granule and pebbles; trough cross-bedded on a large to giant scale, current ripples and primary current lineation common.|16-MAY-23
68748|Top Lily Sandstone Member|Relationships and boundaries|Lower contact is conformable and gradational with the Wangalinji Member. The contact is placed where shale and siltstone give way to pink, fine-grained lithic sandstone over 10-15 m. The upper contact, with the No Mans Sandstone Member in the type section, is sharp and locally erosive, but essentially conformable. In outcrops other than the type section and environs, the No Mans Sandstone Member is absent, and the Top Lily Sandstone Member is overlain, apparently conformably, by the Crow Formation. The boundary is placed at the abrupt transition from fine-grained lithic and quartz sandstone into shale. Parent unit: Playford Sandstone.|16-MAY-23
68748|Top Lily Sandstone Member|Age reasons|A maximum age of 1591+/-10 Ma, based on reworked tuffaceous material from the underlying Lawn Hill Formation (Page et al 2000) in LAWN HILL, or 1595+/-6 Ma based on tuffs in the Lawn Hill Formation in the same area (Page and Sweet 1998). The interpreted age range of 1500-1400 Ma for the South Nicholson Group is based on its correlation with the Roper Group of the southern McArthur Basin (Dunn et al 1966; Plumb & Derrick 1975). Ages of 1492+/-4 and 1493+/-4 Ma for tuffaceous material from the Mainoru Formation in the Roper Group (Jackson et al 1999) provides the most reliable estimate for the age of the lower part of that Group, and hence for the Playford Sandstone and its members.|16-MAY-23
68748|Top Lily Sandstone Member|Correlations|None known, but it is likely that sandstones low in the Renner Group (Hussey et al 2001) and the Roper Group (Jackson et al 1999) are in part correlative, given the overall correlation between these groups.|16-MAY-23
68748|Top Lily Sandstone Member|Defn author|Rawlings, D.J. [approved 11-APR-2005]|16-MAY-23
68748|Top Lily Sandstone Member|Comments|Uppermost of three members making up the Playford Sandstone in its type section. Note: All locations are based on the GDA94 geodetic datum. Standard series 1:250 000 sheet names are shown in upper case.|16-MAY-23
68748|Top Lily Sandstone Member|References|**DUNN P.R., Plumb K.A. and Roberts H.G. 1966. A proposal for time-stratigraphic subdivision of the Australian Precambrian. Journal of the Geological Society of Australia, 13, 593-608.  **HUSSEY K.J., Beier P.R., Crispe A.J., Donnellan N. and Kruse P.D. 2001. Helen Springs, Northern Territory (Second Edition); 1:250 000 geological series, sheet SE53-10.   **JACKSON M.J., Sweet I.P., Page R.W. and Bradshaw B.E., 1999. The South Nicholson and Roper Groups: evidence for the early Proterozoic Roper Superbasin. In: Bradshaw B.E. and Scott D.L. (Eds.), Integrated basin analysis of the Isa Superbasin using seismic, well-log and geopotential data: an evaluation of the economic potential of the northern Lawn Hill Platform. Australian Geological Survey Organisation, Record 1999/19 (unpaginated).    **PAGE R.W., Jackson M.J. and Krassay A.A., 2000. Constraining sequence stratigraphy in north Australian basins: SHRIMP U-Pb zircon geochronology between Mt Isa and McArthur River. Australian Journal of Earth Sciences, 47, 3; 431-459.  **PAGE R.W. and Sweet I.P., 1998. Geochronology of basin phases in the western Mount Isa Inlier, and correlation with the McArthur Basin. Australian Journal of Earth Sciences, 45, 2; 219-232.  **PLUMB K.A. and Derrick G.M., 1975. Geology of the Proterozoic rocks of the Kimberley to Mount Isa Region. In Knight C.L. (Editor), Economic Geology of Australia and Papua New Guinea, 1. Metals. The Australasian Institute of Mining and Metallurgy, Monograph Series, 5, 217-252.  **SMITH J.W. and Roberts H.G., 1963. Mount Drummond, N.T. (First Edition); 1:250,000 geological series, sheet SE53-12. Bureau of Mineral Resources, Geology and Geophysics, Map and Explanatory Notes.  **SWEET I.P., 1984. Carrara Range region, Northern Territory (First Edition); 1:100,000 geological series, portions of sheets 6460 and 6360. Bureau of Mineral Resources, Geology and Geophysics, Explanatory Notes.|16-MAY-23
18425|Top Rocky Rhyolite|Name source|From Top Rocky Waterhole, in Musselbrook Creek, at GR 852387 in the Carrara 1:100 000 Sheet area (Sheet 6460).|10-OCT-23
18425|Top Rocky Rhyolite|Name source|Name derived from Top Rocky Waterhole, a permanent waterhole in Musselbrook Creek (GDA 94; 18.62°S; 137.70°E) (Sweet and Mond, 1980)|
18425|Top Rocky Rhyolite|Unit history|Unit was originally mapped as “unnamed volcanic unit” of the Carrara Range Formation (now superseded) by Smith and Roberts (1963) in the MOUNT DRUMMOND First Edition 1:250 000 mapsheet. Subsequently, the Carrara Range Formation was elevated to the Carrara Range Group by Sweet (1982) and Sweet et al (1984) after mapping of the CARRARA First Edition 1:100 000 mapsheet. The “Top Rocky Rhyolite” was defined therein as the uppermost formation of the Carrara Range Group. This stratigraphic position was retained in the Second Edition MOUNT DRUMMOND 1:250 000 mapsheet (Rawlings et al, 2006). In the Third Edition MOUNT DRUMMOND 1: 250 000 mapsheet (Simmons et al, 2023a, b), the Top Rocky Rhyolite is unconformably overlain by the Boomerang Formation and the Drummond Formation, the latter of which forms the uppermost formation of the Carrara Range Group.|
18425|Top Rocky Rhyolite|Unit history|Formerly an unnamed volcanic member within the Carrara Range Formation (now a Garoup) of Smith & Roberts (1963).|10-OCT-23
18425|Top Rocky Rhyolite|Constituents|Includes two informal subunits: a lower coherent rhyolite subunit (LPctr) and an upper conglomerate subunit (LPctc) (Sweet 1984; Sweet et al, 1984). These are not distinguished on the Third Edition MOUNT DRUMMOND 1:250 000 mapsheet, as they are too thin to be differentiated at that scale.|
18425|Top Rocky Rhyolite|Geomorphic expression|Forms a series of narrow, approximately east–west-trending ridges in the Carrara Range region, up to approximately 1 km wide.|
18425|Top Rocky Rhyolite|Type section locality|From grid ref. 750324 (base) to 750329 (top) in the Carrara 1:100 000 Sheet area, Northern Territory. The section is 250 m thick.|10-OCT-23
18425|Top Rocky Rhyolite|Type section locality|North–south-oriented type section across an east–west-trending strike ridge. Base of Type Section at (GDA 94) 18.6800°S 137.6082°E (53K 775109mE 7932573mN); Top of Type Section at 18.6751°S 137.6079°E (775086mE 7933116mN; Sweet, 1982).|
18425|Top Rocky Rhyolite|Extent|Total outcrop area extent of approximately 20 km2 across the MOUNT DRUMMOND 1:250 000 mapsheet. Exposed as a series of narrow, approximately east–west-trending strike ridges which form an outcrop belt approximately 1 km wide; extends from approximately 6 km west to 20 km east of Mount Drummond landform. Small inlier also mapped in the Maloney Creek Inlier.|
18425|Top Rocky Rhyolite|Extent|A belt up to 1 km wide extending from 6 km southwest of Mount Drummond to 20 km east of it; total outcrop area is about 20 km2.|10-OCT-23
18425|Top Rocky Rhyolite|Thickness range|Approximately 250 m thick at the type section. Extends to approximately 400 m thick to east of type section; approximately 100 m thick to the west. The laterally continuous coherent rhyolite subunit (LPctr) reaches up to approximately 350 m thick, and the discontinuous conglomerate subunit (LPctc) reaches up to 200 m thick (Rawlings et al, 2008).|
18425|Top Rocky Rhyolite|Lithology|Reddish-brown, structureless feldspar porphyry with little lateral variation. Minor flow banding, spherulitic rhyolite, and interbedded trachyte or basalt. About 400 m thick in the east to 100 m in the west.|10-OCT-23
18425|Top Rocky Rhyolite|Lithology|Two informally mapped subunits, a lower coherent rhyolite subunit (LPctr) and an upper conglomerate subunit (LPctc). LPctr: Silicified to crumbly porphyritic rhyolite, with euhedral to subhedral K-feldspar and quartz phenocrysts dispersed in a cryptocrystalline quartzofeldspathic groundmass. LPctc: Sub-angular to sub-rounded pebble to boulder conglomerate in a poorly sorted lithic mud-sand-gravel matrix. Predominantly rhyolite clasts near base of unit, becomes increasingly polymictic up section. Localised intervals of trough cross-bedded to planar cross-bedded, medium- to coarse-grained lithic sandstone occur up-section (Rawlings et al, 2008).|
18425|Top Rocky Rhyolite|Depositional environment|Coherent rhyolite unit likely formed via the eruption of a single or composite lava dome, with the development of lava flows, which quickly cooled to form the coherent rhyolite. Overlying conglomeratic unit likely formed due to debris flows, which entrained autobrecciated/loose rhyolite clasts (and eventually clasts of underlying stratigraphy) and deposited rapidly.|
18425|Top Rocky Rhyolite|Relationships and boundaries|The Top Rocky Rhyolite lies disconformably on the Mitchiebo Volcanics and is overlain, disconformably by the Musselbrook Formation. The basal disconformity is highly irregular, with relief of up to 130 m, while the upper unconformity is marked by lenses of pebble to cobble conglomerate in the overlying Musselbrook Formation; a high proportion of the clasts are of rhyolite from the underlying volcanics.|10-OCT-23
18425|Top Rocky Rhyolite|Relationships and boundaries|Unconformably overlies the Gator Sandstone or locally the Mitchiebo Volcanics, with boundary discordance visible from satellite imagery. Possible structural controls on boundary with underlying Gator Sandstone. Unconformably underlies the Boomerang Formation in the Carrara Range region, with the contact marked by an erosional surface and conglomerate unit.  In the Maloney Creek Inlier, the unit unconformably underlies the Bullrush Conglomerate of the McNamara Group, due to highly irregular palaeotopography.|
18425|Top Rocky Rhyolite|Identifying features|Discontinuous, polymictic, pebble to boulder conglomerate defining upper section of formation in places.|
18425|Top Rocky Rhyolite|Age reasons|Proterozoic, Carpentarian - correlated with sequences of known Carpentarian age by Plumb & Derrick (1975) and Hutton & Sweet (1982, in press).|10-OCT-23
18425|Top Rocky Rhyolite|Age reasons|Crystallisation age derived from U-Pb SHRIMP isotopic dating of igneous zircons: 1725 ± 3 Ma (Page et al, 2000).|
18425|Top Rocky Rhyolite|Correlations|Age equivalent to the intrusive phases of the Peters Creek Volcanics south of the Murphy Province, and the Hobblechain Rhyolite and Packsaddle Microgranite of the southeastern McArthur Basin (Page et al, 2000).|
18425|Top Rocky Rhyolite|Alteration and Mineralisation|Silicified.|
18425|Top Rocky Rhyolite|Geophysical Expression|Moderate to high magnetic response. Could be due in part to stratigraphic proximity to highly magnetic mafic volcanic units.|
18425|Top Rocky Rhyolite|Geochemistry|See Carson CJ, Jarrett AJM, Anderson JR, Champion DC and Henson PA, 2020. Exploring for the Future – Whole rock geochemistry data release of sedimentary and igneous rocks from the South Nicholson region, Northern Territory and Queensland. Geoscience Australia Record 2020/02.|
18425|Top Rocky Rhyolite|Defn author|Elliot Foley, Jack Simmons, Ben Williams, Charles Verdel (Northern Territory Geological Survey), Chris Carson (Geoscience Australia) 31-MAY-2023.|
18425|Top Rocky Rhyolite|Comments|Note: Standard series 1: 100 000 and 1: 250 000 mapsheet names are shown in uppercase.|
18425|Top Rocky Rhyolite|References|Carson CJ, Jarrett AJM, Anderson JR, Champion DC and Henson PA, 2020. Exploring for the Future - Whole rock geochemistry data release of sedimentary and igneous rocks from the South Nicholson region, Northern Territory and Queensland. Geoscience Australia Record 2020/02.  **Carson, C. J., Kositcin, N., Anderson, J. R., and Henson, P. A. in prep. A revised Proterozoic tectono-stratigraphy of the South Nicholson region, Northern Territory, Australia - insights from SHRIMP U-Pb detrital zircon geochronology. Australian Journal of Earth Sciences.  **Page RW, Jackson MJ and Krassay AA, 2000. Constraining sequence stratigraphy in north Australian basins: SHRIMP U-Pb zircon geochronology between Mt Isa and McArthur River. Australian Journal of Earth Sciences 47(3), 431-459.  **Rawlings DJ, Sweet IP and Kruse PD, 2006. Mount Drummond, NT (Second Edition). 1:250 000 Geological Map, Sheet SE 53-12. Northern Territory Geological Survey, Darwin, Northern Territory.  **Rawlings DJ, Sweet IP and Kruse PD, 2008. Mount Drummond, NT (Second Edition). 1:250 000 Geological Map Series Explanatory Notes, Sheet SE 53-12. Northern Territory Geological Survey, Darwin, Northern Territory.  **Simmons JM, Williams B, Carson, C and Verdel C, 2023a. Mount Drummond, Northern Territory 1:250 000 Geological Map, Sheet SE 53-12 (Third Edition). Northern Territory Geological Survey, Darwin, Northern Territory.  **Simmons JM, Williams B, Carson, C and Verdel C, 2023b. Mount Drummond, Northern Territory 1:250 000 Geological Map Explanatory Notes, Sheet SE 53-12 (Third Edition). Northern Territory Geological Survey, Darwin, Northern Territory.  **Smith JW and Roberts HG, 1963. Mount Drummond, NT (First Edition). 1:250 000 Geological Map Series Explanatory Notes, Sheet 53-12. Bureau of Mineral Resources, Canberra.  **Sweet IP, 1982. Definition of new stratigraphic units names in the Carrara Range region. Bureau of Mineral Resources, Report 242.  **Sweet IP, 1984. Carrara Range region, Northern Territory (First Edition). 1:100 000 geological map commentary, portions of 6360 and 6460. Bureau of Mineral Resources, Canberra.  **Sweet IP and Mond A, 1980. The geology of the Carrara Range section, Northern Territory. Bureau of Mineral Resources, Geology and Geophysics, Record 1980/76.  **Sweet IP, Mond A and Stirzaker J, 1984. Carrara Range Region, Northern Territory (First Edition). 1:100 000 Geological Map Series, Carrara 6460 and Mitchiebo 6360. Bureau of Mineral Resources, Canberra.|
18425|Top Rocky Rhyolite|Defn approved by|Brakel A.T. (subject to Hutton and Sweet reference details being entered when published)|10-OCT-23
18425|Top Rocky Rhyolite|Defn Reference|83/23538 Sweet, I.P., 1982.|10-OCT-23
18425|Top Rocky Rhyolite|Resdate|23-MAY-1980|10-OCT-23
18426|Top Springs Limestone|Name source|Top Spring property, northern Wallhallow 1:250 000 sheet area.|16-MAY-23
18426|Top Springs Limestone|Geomorphic expression|Flat to undulating plains with karstic pavements, lapies, kamenitza, towers and dolines.|16-MAY-23
18426|Top Springs Limestone|Type section locality|7-99 m in cored drillhole DD86SC-2, Kilgour 1:100 000 AMG 883885 (latitude 17o17.3'S, longitude 135o49.8'E). Core stored at NTGS Core Library, Darwin.|16-MAY-23
18426|Top Springs Limestone|Extent|Southern Bauhinia Downs and northern Wallhallow 1:250 000 sheet area.|16-MAY-23
18426|Top Springs Limestone|Thickness range|Maximum known 92 m in type section; 73 +/- in cored drillhile DD83SC-1 (Kilgour 1:100 000 AMG 884883).|16-MAY-23
18426|Top Springs Limestone|Lithology|Grey, partially dolomitised mottled, bioclastic, peloid and onkoid limestone; minor grey brecciated limestone, pink to pale brown cryptalgal laminite; rare grey fenestral limestone.|16-MAY-23
18426|Top Springs Limestone|Relationships and boundaries|Rests on Bukalara Sandstone with probable disconformity. Possibly overlain by Anthony Lagoon beds (Plumb and Rhodes, 1963, 1964), but relationships are obscured by Cretaceous cover.|16-MAY-23
18426|Top Springs Limestone|Structure and Metamorphism|Generally flat-lying.|16-MAY-23
18426|Top Springs Limestone|Age reasons|Ordian (early :Middle Cambrian) based on trilobite Redlichia; supported by branchiopods, hyoliths, molluscs and other invertebrate fossils known also from the lower Tindall Limestone.|16-MAY-23
18426|Top Springs Limestone|Correlations|Lower, possibly also upper Tindall Limestone and numerous Ordian lithostratigraphic units.|16-MAY-23
18426|Top Springs Limestone|Proposed publication|Bauhinia Downs 1:250 000 Geol. Series, Explan. Notes, NT Geological Survey.|16-MAY-23
18426|Top Springs Limestone|Defn approved by|Kruse P.D., after Plumb and Rhodes 1963, 1964|16-MAY-23
18426|Top Springs Limestone|Status|1|16-MAY-23
26328|Tops Member|Name source|Mt Tops on Barrow 1:100 000 sheet (AMG GR LR954849).|16-MAY-23
26328|Tops Member|Unit history|Lower part of 'red lithic unit' (PuCs2) of Shaw et al. (1979), p.47, and Shaw and Warren (1975).|16-MAY-23
26328|Tops Member|Geomorphic expression|Rounded hills covered with Triodia.|16-MAY-23
26328|Tops Member|Type section locality|Base of section 29 km southeast of Barrow Creek township at latitude 21o44'20"S, longitude 134o03'30"E on Home of Bullion 1:100 000 sheet. Section in two parts: AMG GR MR027956 (base) to MR025954: MR013954 to MR015951 (top). Conformable between Forster and Adnera members at this locality.|16-MAY-23
26328|Tops Member|Extent|Southwest quarter of Barrow Creek, northern Alcoota, southeast Mount Peake and northeast Napperby 1:250 000 sheets.|16-MAY-23
26328|Tops Member|Thickness range|114 m at type section. 283 m exposed at AMG GR LR680679 near southern edge of Barrow 1:100 000 sheet (incomplete section). Thickens towards southwest.|16-MAY-23
26328|Tops Member|Lithology|Red-brown, medium to coarse-grained, friable arkose, feldspathic arenite and siltstone. Generally well cross-bedded. Minor conglomerate and dolostone.|16-MAY-23
26328|Tops Member|Relationships and boundaries|Conformable over Forster Member or unconformably over early Proterozoic basement. Lower boundary picked at first consistent beds of friabale red-brown arkose overlying hard sandstones of the Forster Member. Conformably overlain by Adnera Member. Top picked at top of last major redbeds below first consistent development of white quartz arenite of Adnera Member.|16-MAY-23
26328|Tops Member|Structure and Metamorphism|Typically horizontal or dipping gently to the southwest. May dip steeply near faults.|16-MAY-23
26328|Tops Member|Age reasons|Late Proterozoic (late Adelaidean) as it contains Mt Skinner assemblage (Wade, 1969), which has Tribrachidium in common with Ediacara assemblage (Wade pers. com., 1987).|16-MAY-23
26328|Tops Member|Correlations|Pound Subgroup of Adelaide Geosyncline. Arumbera Sandstone II of Amadeus basin based on occurrence of Hallidaya brueri. Probably correlates in part with the Andagera Formation to the northeast.|16-MAY-23
26328|Tops Member|Category|2                      updated|16-MAY-23
24535|Treasure Volcanics|Name source|Treasure tungsten mine at GR 199869, Hatches 1:100 0000 Sheet area, Frew River 1:250 000 Sheet area.|16-MAY-23
24535|Treasure Volcanics|Type section locality|In the southwest of the Hatches 1:100 000 Sheet area, from GR 128983, 8 km northwest of the Pioneer mine (latitude 20o52'10"S, longitude 135o11'00"E), where the formation conformably overlies Taragan Sandstone, to GR 098941, where it is overlain conformably (or disconformably) by Unimbra Sandstone. In this 5 km-long section a sequence about 1700 m thick is exposed, consisting of felsic lavas, subordinate basaltic lavas, and interlayered arenite bands. The sequence, together with some granophyre sills, dips 15-40o SW.|16-MAY-23
24535|Treasure Volcanics|Extent|Central and eastern part of the Davenport Province, mainly in the southern part of Hatches and western part of Hanlon 1:100 000 Sheet areas, frew River 1:125 000 Sheet area.|16-MAY-23
24535|Treasure Volcanics|Thickness range|0 to possibly about 3500 m.|16-MAY-23
24535|Treasure Volcanics|Lithology|Moderately recessive felsic lava containing small phenocrysts of albite +/- quartz +/- pseudomorphed ferromagnesian minerals; suboradinate interlayered generally ridge-forming quartzose to feldspathic and volcaniclastic arenite and recessive basaltic lava; minor bedded tuff and pebbly arenite.|16-MAY-23
24535|Treasure Volcanics|Relationships and boundaries|Conformable on and in places interfingers with Taragan Sandstone. Overlain conformably and possibly disconformably by, and also interfingers with, Unimbra Sandstone. Intruded by granophyre and dolerite/gabbro sills.|16-MAY-23
24535|Treasure Volcanics|Age reasons|Younger than 1870 m.y. - U-Pb zircon age for volcanics within the Warramunga Group overlain unconformably by the Hatches Creek Group. Older than 1640 m.y. - Rb-Sr whole-rock age of granite intruding the Hatches Creek Group.|16-MAY-23
24535|Treasure Volcanics|Defn author|Blake D.H., Stewart A.J., Sweet I.P., Wyche S., 1985.|16-MAY-23
24535|Treasure Volcanics|Proposed publication|BMR Record 257|16-MAY-23
24535|Treasure Volcanics|Comments|Remarks: Stratigraphically equivalent to parts of the Mia Mia Volcanics and Epenarra Volcanics, but differs in lithology and is geographically separated from these other two units, and was probably derived from different volcanic centres. Part of the Ooradidgee Subgroup of the Hatches Creek Group.|16-MAY-23
24535|Treasure Volcanics|Defn Reference|86/25362|16-MAY-23
24535|Treasure Volcanics|Proposer|Blake D.H.|16-MAY-23
24535|Treasure Volcanics|Resdate|07-OCT-1981|16-MAY-23
24536|Trephina granitic gneiss|Name source|Trephina Creek, a tributary of Ross River centred on 23o29'S, 134o21'E in the Alice Springs 1:250 000 Sheet area.|16-MAY-23
24536|Trephina granitic gneiss|Unit history|Previously mapped by Wells & others (1968) as undivided Arunta Complex.|16-MAY-23
24536|Trephina granitic gneiss|Type section locality|Reference area: Typical exposures of the unit can be examined 4 to 5 km north of Whistleduck Bore.|16-MAY-23
24536|Trephina granitic gneiss|Extent|The unit occupies an extensive, flat, relatively low-lying region of about 50 km2 in the central headwaters of Trephina Creek centred on GR 5751-270090, Laughlen 1:100 000 Sheet area.|16-MAY-23
24536|Trephina granitic gneiss|Lithology|A biotite granitic gneiss containing sparsely disseminated potassium feldspar megacrysts. The unit includes enclosed bodies of amphibolite. Additional Information on lithology is given in Shaw & others (in preparation b).|16-MAY-23
24536|Trephina granitic gneiss|Relationships and boundaries|Has discordant contacts against unassigned gneisses (pC) of the northern Wigley Block; intruded by the Whistleduck Dyke Swarm.|16-MAY-23
24536|Trephina granitic gneiss|Age reasons|Probably Mid-Proterozoic. Lithologically correlated and hance may be co-eval with Jennings Granitic Gneiss, which is considered to have been intruded at about 1700 m.y. (Stewart in Shaw & others, 1979; Armstrong & Stewart, 1975).|16-MAY-23
24536|Trephina granitic gneiss|Proposed publication|Stewart & others, in prep.|16-MAY-23
24536|Trephina granitic gneiss|Defn Reference|80/20787|16-MAY-23
24536|Trephina granitic gneiss|Proposer|Shaw R.D. (in Shaw & others, in prep.).|16-MAY-23
24536|Trephina granitic gneiss|Unit name|Trephina Granitic Gneiss (informal)|16-MAY-23
24544|Two Sisters Granite|Name source|Two Sisters Hills, GR FL690585, Reynolds River (5071) 1:100 0000 sheet area.|16-MAY-23
24544|Two Sisters Granite|Unit history|Included in Litchfield Province by Walpole and others (1968). Two Sisters and Fog Bay granites of Berkman (1980) Two Sisters Granite of Pietsch (1983; 1986) Hickey (1985), Fahey and Edgoose (1986).|16-MAY-23
24544|Two Sisters Granite|Type section locality|Vicinity of GR 814673, Bynoe 1:100 000 sheet area (latitude 12o57', longitude 130o40'). Exposed as low boulder-strewn pavements.|16-MAY-23
24544|Two Sisters Granite|Extent|Discontinuous outcrop between the Reynolds and Finniss Rivers on the Bynoe, Reynolds River, Anson and Fog Bay 1:100 000 sheet areas. Stocks in the Bynoe Harbour area. Total outcrop area approximately 480 km2.|16-MAY-23
24544|Two Sisters Granite|Lithology|Grey to pink, medium to coarsely crystalline, weakly to strongly foliated, commonly garnetiferous granite, adamellite and granodiorite.|16-MAY-23
24544|Two Sisters Granite|Relationships and boundaries|Intrudes the Burrell Creek Formation and Welltree Metamorphics. Faulted contact with Fog Bay Metamorphics. Unconformably overlain by Phanerozoic sediments.|16-MAY-23
24544|Two Sisters Granite|Age reasons|Early Proterozoic. Part of a suite which crystallised at about 1850 Ma (Page and others, 1985). Intrudes metamorphics which formed during the 1870 Ma event of the Top End Orogeny (Needham and others, 1985). Hydrothermally altered at about 1780 Ma (Page and othes, 1985).|16-MAY-23
24544|Two Sisters Granite|Proposed publication|Darwin 1:250 000 Series Explanatory Notes|16-MAY-23
24544|Two Sisters Granite|Comments|Published updated                    21/4/1988|16-MAY-23
24544|Two Sisters Granite|Proposer|Pietsch B.A.|16-MAY-23
24544|Two Sisters Granite|Status|1|16-MAY-23
24545|Tyson Creek granulite|Name source|Tyson Creek (metric grid reference: 305000E, 7535000N) headwaters of which are hills of Tyson Creek granulite, Tea Tree 1:100 0000 Sheet area.|16-MAY-23
24545|Tyson Creek granulite|Type section locality|At metric grid reference 303100E, 7524900N, 4 km ENE of Pine Hill Homestead, Tea Tree 1:100 000 Sheet area. Here, waterfall in creek shows good exposure of Tyson Creek granulite intruded by Possum Creek Charnockite.|16-MAY-23
24545|Tyson Creek granulite|Extent|Southeastern part of Anmatjira Range, Tea Tree and Reynolds Range 1:100 000 Sheet areas.|16-MAY-23
24545|Tyson Creek granulite|Lithology|Two different rock-types (1) Mafic granulite (biotite-hypersthene-clinopyroxene-labradorite (or bytownite) interlayered with (2) Felsic granulite (biotite-garnet-andesine-orthoclase). In places, felsic granulite forms masses large enough to be mapped as separate bodies within the larger interlayered granulite body.|16-MAY-23
24545|Tyson Creek granulite|Relationships and boundaries|Rocks older than or basement to Tyson Creek granulite are not exposed. It adjoins Weldon metamorphics (q.v.) with apparent conformity, but which is older is unknown (no facings available). Is intruded by Anmatjira Orthogneiss, by Aloolya Gneiss (q.v.), by the Possum Creek Charnockite (q.v.), by an unnamed porphyritic charnockitic granite 3 km NW of Sandy Creek Bore (Tea Tree 1:100 000) Sheet area), and by a dolerite dyke.|16-MAY-23
24545|Tyson Creek granulite|Identifying features|Reason for Proposed Name: A very distinctive and easily mapped mafic granulite body, with strongly different mineralogical and chemical composition from adjoining rocks.|16-MAY-23
24545|Tyson Creek granulite|Age reasons|Time of crystallisation of mafic (igneous?) parent unknown - may be Early Proterozoic. K-Ar date on hornblende from small body adjoining Anmatjira Granite = 1650 m.y. = younger time limit on time of regional metamorphism of granulite, may be thermal metamorphism by Anmatjira Orthogneiss.|16-MAY-23
24545|Tyson Creek granulite|Proposed publication|1. 'Geology of NW Part of Arunta Block, NT' - BMR Publication. 2. Stratigraphic definitions in Arunta Block' - BMR Microfiche Report.|16-MAY-23
24545|Tyson Creek granulite|Defn Reference|80/20787|16-MAY-23
24545|Tyson Creek granulite|Reserved? Yes/No|Yes|16-MAY-23
24545|Tyson Creek granulite|Unit name|Tyson Creek Granulite|16-MAY-23
41854|Udor Granite|Name source|Mount Udor 23o 30' 00" S, 131o 01' 00" E, MOUNT LIEBIG.|16-MAY-23
41854|Udor Granite|Unit history|Previously included within undifferentiated gneiss, schist, amphibolite, quartzite, granite, dolerite and pegmatite of the Arunta Complex, and unnamed granite of the Arunta Complex  (Ranford 1969)|16-MAY-23
41854|Udor Granite|Geomorphic expression|Low rubbly hills and outcrops, with large areas of shallowly buried subcrop.|16-MAY-23
41854|Udor Granite|Type section locality|2 km north of Mount Udor at location 23o 29' 26.64" S, 131o 01' 01.00" E (WGS 84), MOUNT LIEBIG.|16-MAY-23
41854|Udor Granite|Description at type locality|Foliated, equigranular to weakly porphyritic biotite granite, largely equigranular with slightly larger quartz phenocrysts. The metamorphic mineral assemblage in the granite comprises biotite, quartz, plagioclase, K-feldspar, epidote and titanite, with minor muscovite.|16-MAY-23
41854|Udor Granite|Extent|Poorly outcropping in western MOUNT LIEBIG around Mount Kuta Kuta, north of Mount Udor and Mount Udor West and northwest of Mount Putardi. Interpreted on basis of aeromagnetic data to extend south of Mount Udor, Mount Putardi and Mount Peculiar.|16-MAY-23
41854|Udor Granite|Lithology|Foliated, leucocratic equigranular to weakly porphyritic biotite-muscovite granite. Lesser biotite granite and biotite-muscovite-garnet granite.|16-MAY-23
41854|Udor Granite|Relationships and boundaries|Interpreted to intrude Peculiar Complex. Overlain by Putardi Quartzite and Heavitree Quartzite.|16-MAY-23
41854|Udor Granite|Age reasons|late Palaeoproterozoic. A sample from the type locality has a SHRIMP U-Pb zircon age of 1663 +/- 4 Ma (Cross et al in prep).|16-MAY-23
41854|Udor Granite|Correlations|May have correlatives in 1690-1660 Ma felsic migmatites of the Glen Helen Metamorphics (Warren and Shaw 1995)|16-MAY-23
41854|Udor Granite|Comments|Has distinctively low and flat aeromagnetic signature. Metamorphosed to lower to middle amphibolite facies during the 1590-1560 Ma Chewings Orogeny.|16-MAY-23
41854|Udor Granite|References|Cross A, Claoue-Long J, Scrimgeour IR, Close DF & Edgoose CJ, in prep. NTGS-GA Geochronology project, Report 6. Northern Territory Geological Survey, Record **Ranford LC, 1969. Mount Liebig, Northern Territory (First Edition). 1:250 000 geological map series explanatory notes, SF52-16. Bureau of Mineral Resources, Australia. **Scrimgeour IR, Close DF & Edgoose CJ, in prep. Mount Liebig, Northern Territory (Second Edition) 1:250 000 geological map series explanatory notes, SE 52-16. Northern Territory Geological Survey, Darwin. **Warren RG and Shaw RD 1995. Hermannsburg, Northern Territory (Second Edition). 1:250 000 geological map series explanatory notes, SF-53-13. Northern Territory Geological Survey, Darwin.|16-MAY-23
41855|Ulambaura Granodiorite|Name source|Ulambaura outstation 23o16'45" S, 131o55'40" E, MOUNT LIEBIG.|16-MAY-23
41855|Ulambaura Granodiorite|Unit history|Previously included within undifferentiated gneiss, schist, amphibolite, quartzite, granite, dolerite and pegmatite of the Arunta Complex  (Ranford 1969)|16-MAY-23
41855|Ulambaura Granodiorite|Geomorphic expression|Rounded hills with bouldery outcrop|16-MAY-23
41855|Ulambaura Granodiorite|Type section locality|Outcrops ~500m southeast of Alkipi (Mt Larrie) outstation at location 23o16'25.58"S, 131o50'24.40"E (WGS 84), MOUNT LIEBIG.|16-MAY-23
41855|Ulambaura Granodiorite|Description at type locality|Foliated, porphyritic hornblende-biotite granodiorite/tonalite, with roughly equal proportions of hornblende and biotite, and small phenocrysts of plagioclase.   K-feldspar is rare to absent. Minor late epidote, chlorite and muscovite reflect greenschist facies retrogression.|16-MAY-23
41855|Ulambaura Granodiorite|Extent|Numerous elongate bodies up to 3 km in length, intruding Yaya Metamorphic Complex in a 30 km long east-trending belt, north and northwest of Belt Range (10-40 km west and southwest of Papunya community), MOUNT LIEBIG.|16-MAY-23
41855|Ulambaura Granodiorite|Lithology|Foliated, variably porphyritic hornblende granodiorite and tonalite, with phenocrysts of plagioclase 0.3-1.0 cm in diameter. Coarse igneous hornblende is variably preserved, and is overprinted by secondary hornblende and biotite with minor titanite and epidote that are metamorphic in origin. Less commonly, hornblende-free medium-grained biotite granodiorite occurs.|16-MAY-23
41855|Ulambaura Granodiorite|Relationships and boundaries|Intrudes Alkipi Metamorphics and unnamed felsic gneiss of the Yaya Metamorphic Complex|16-MAY-23
41855|Ulambaura Granodiorite|Age reasons|late Palaeoproterozoic. Intrudes Alkipi Metamorphics, which were deposited in the interval 1660-1640 Ma. Interpreted to have intruded during 1640-1635 Ma Liebig Orogeny, along with other granites in the region.|16-MAY-23
41855|Ulambaura Granodiorite|Correlations|No direct correlatives. The unit is likely to be of a similar age to the Illili and Waluwiya Suites and Papunya Igneous Complex.|16-MAY-23
41855|Ulambaura Granodiorite|Comments|The unit was metamorphosed at upper amphibolite facies conditions during the 1590-1560 Ma Chewings Orogeny.|16-MAY-23
41855|Ulambaura Granodiorite|References|Ranford LC, 1969. Mount Liebig, Northern Territory (First Edition). 1:250 000 geological map series explanatory notes, SF52-16. Bureau of Mineral Resources, Australia. **Scrimgeour IR, Close DF & Edgoose CJ, in prep. Mount Liebig, Northern Territory (Second Edition) 1:250 000 geological map series explanatory notes, SE 52-16. Northern Territory Geological Survey, Darwin.|16-MAY-23
24546|Uldirra Porphyry|Name source|Uldirra Hill, metric grid reference 218529 on Napperby 1:250 000 Sheet, SF53-9; situated in NE portion of Uldirra Porphyry.  Uldirra Hill itself is a prominent quartz vein emplaced in the Porphyry.|16-MAY-23
24546|Uldirra Porphyry|Type section locality|3 km of Uldirra Hill, at metric GR 21755257; locality is at margin of range of hills of porphyry, well exposed, shows several rock-types in close proximity including: white leucocratic porphyritic microgranite with abundant monazite phenocrysts (dark yellow) (in addition to quartz, feldspar and chlorite), normal porphyritic microgranite with some sphene and allanite phenocrysts (as well as the usual quartz, feldspars and chlorite), and some quartz-feldspar rock.|16-MAY-23
24546|Uldirra Porphyry|Extent|In Ngalurbindi Hills, S. part of Denison 1:100 0000 Sheet in NW part of Napperby 1:250 000 Sheet. Porphyry body measures approx. 16 km NW to SE, by 6 km NE to SW.|16-MAY-23
24546|Uldirra Porphyry|Lithology|Pale grey to white porphyritic microgranite comprisisng phenocrysts of quartz (rounded), microcline, plagioclase (ranging from sodic andesine through oligoclase to, rarely, albite) and biotite or chlorite in a recrystallised groundmass of polygonal quartz, microcline, plagioclase, and biotite or chlorite. Other constituents forming phenocrysts in some samples include monazite (several localities), muscovite, allanite and sphene; other groundmass constituents, not included at every locality, are muscovite, hematite and zircon. Plagioclase is commonly much sericitised or saussuritised. Rock is weakly foliated. Subsidiary rock-types include porphyritic microgranodiorite, muscovite-feldspar-quartz rock and quartz feldspar rock.|16-MAY-23
24546|Uldirra Porphyry|Relationships and boundaries|Largely unknown with respect to what it intrudes and what intrudes it. Adjoins and faulted against Ngalurbindi Orthogneiss (name previously submitted and approved as Ngalurbindi Granite) on N. and E. Adjoins unnamed bodies of granite and granodiorite on W, but nowhere have intrusive apophyses, xenoliths or other evidence of age relationships yet been observed.|16-MAY-23
24546|Uldirra Porphyry|Identifying features|Reason for proposed name: a distinctively textured and mappable body different from surrounding granites and augen gneiss; characterised by unusual abundance of monazite.|16-MAY-23
24546|Uldirra Porphyry|Age reasons|No isotopic date yet determined. Probably mid-Proterozoic, about 1500 m.y.; nearest 'date' is 1500-1800 (L P Black, pers. comm., 1975) on Napperby Orthogneiss (published in BMR Report 125 as Napperby Granite), which adjoins Ngalurbindi Orthogneiss.|16-MAY-23
24546|Uldirra Porphyry|Proposed publication|1. Denison 1:100 000 Geological Sheet and BMR Commentary on same.   2. Stratigaraphic definitions in Arunta Block' - BMR Microfiche Report.|16-MAY-23
24546|Uldirra Porphyry|Defn Reference|80/20787|16-MAY-23
24546|Uldirra Porphyry|Proposer|Stewart A.J.|16-MAY-23
24546|Uldirra Porphyry|Resdate|01-NOV-1978|16-MAY-23
24546|Uldirra Porphyry|Reserved? Yes/No|Yes|16-MAY-23
24547|Ulgnamba Lignite Member|Name source|Ulgnamba Bore, GR 461419, in the Alice Springs 1:250 000 Sheet area.|16-MAY-23
24547|Ulgnamba Lignite Member|Unit history|Previously mapped as undivided Tertiary sediments by Wells & others, 1968. (See also definition of Hale Formation).|16-MAY-23
24547|Ulgnamba Lignite Member|Type section locality|Near base of section just above basement in Diamond Drill Hole BMR 2 at GR 240088 Alice Springs 1:250 000 Sheet area.|16-MAY-23
24547|Ulgnamba Lignite Member|Extent|As lenses identified in subcrop in several drillholes into the Hale Basin under the Hale Plain.|16-MAY-23
24547|Ulgnamba Lignite Member|Thickness range|4 m.|16-MAY-23
24547|Ulgnamba Lignite Member|Lithology|Lignite, carbonaceous shale.|16-MAY-23
24547|Ulgnamba Lignite Member|Relationships and boundaries|The unit occurs near the base of the Hale formation in BMR DDH 2, near but not directly on basement. Elsewhere the member occurs as lenses in the Hale Formation, but always at the same stratigraphic level.|16-MAY-23
24547|Ulgnamba Lignite Member|Age reasons|Tertiary, possibly Eocene, but no studies of spores have been published.|16-MAY-23
24547|Ulgnamba Lignite Member|Proposed publication|Stewart & others, in prep.|16-MAY-23
24547|Ulgnamba Lignite Member|References|01/31585; 01/31586; B026; 01/31593; RC79/047; 98/29305; 83/23758.|16-MAY-23
24547|Ulgnamba Lignite Member|Defn Reference|80/20787|16-MAY-23
24547|Ulgnamba Lignite Member|Proposer|Shaw R.D., Slenior B.R. (in Shaw and others, in prep)|16-MAY-23
37622|Ulta Limestone|Name source|Ulta Creek, on Santa Teresa 5749 1:100 000 sheet.|16-MAY-23
37622|Ulta Limestone|Geomorphic expression|Low mesas with local relief of up to 30m, but more typically 10-20m, or rubbly outcrops in cores of aeolian dunes (i.e. where unit has been exposed by deflation of red Quaternary sand).|16-MAY-23
37622|Ulta Limestone|Type section locality|Measured section at 24o 13' 13''S, 134o 13' 32''E, which is also type locality of Kangaroo Well Local Fauna. Depositional attributes at type section comparatively well preserved.|16-MAY-23
37622|Ulta Limestone|Extent|Sinuous line of discontinuous outcrop extending about 50km across western exposure of Ooraminna Anticline and eastern exposure of Orange Creek Syncline, following structure in Amadeus Basin. Mapped on current (First Edition) 1:250,000 Rodinga Geological Sheet SG/53-02 as "Tb, silicrete (grey billy)" and "Tl, chalcedonic limestone, siltstone and calcareous sandstone containing freshwater gastropods" (Ranford et al. 1968, Cook 1969).  These generic map units are widespread across Rodinga and adjacent first addition map sheets (eg, Henbury SG/53-01, Hale River SG/53-03, Kulgera SG/53-05, Finke SG/53-06), encompassing strata deposited in a variety of structural settings and of possibly varying age.  Concept of Ulta Limestone expressly limited as defined herein.|16-MAY-23
37622|Ulta Limestone|Thickness range|Up to an estimated 40m.|16-MAY-23
37622|Ulta Limestone|Lithology|White to dark yellowish-orange limestone, predominantly calcimudstone containing terrestrial and freshwater gastropods, with minor calcarenite and conglomeratic limestone, some of which contain vertebrate fossils, plus diagenetic end-members including varieties of caliche, chalcedonic limestone and chalcedony (grey billy). Plane to lenticular bedforms, with scour and fill structures.|16-MAY-23
37622|Ulta Limestone|Depositional environment|Freshwater palaeochannel.|16-MAY-23
37622|Ulta Limestone|Fossils|Unit is type formation of  of gastropods Physastra rodingae McMichael, 1968, Meracomelon lloydi McMicheal, 1968 and Bothriembyron praecursor McMichael, 1968. Flannery et al. (1982) described a marsupial Balbaroo sp. from unit.  Ostracoda, Gastropoda, Osteichthys, Amphibia, Reptilia, Aves and Marsupialia listed in, for example, Lloyd (1968), Stirton et al. (1968) and Rich (1991).|16-MAY-23
37622|Ulta Limestone|Relationships and boundaries|Colluvium, alluvium and red aeolian sand generally mask base of unit. At 24degrees 14' S, 134degrees 14' E (2.14 km at 197degrees from type locality) and at 24degrees 16' 42'' S, 134degrees 10' 35'' E (8.13 km at 212degrees from type locality), unit rests with angular unconformity on Mereenie  Sandstone of Amadeus Basin. No superposed strata other than Quaternary aeolian sand locally draping unit.|16-MAY-23
37622|Ulta Limestone|Structure and Metamorphism|Essentially flat-lying. Very low-angle bedding might either reflect primary depositional attitudes, or could be evidence of very mild tilting.|16-MAY-23
37622|Ulta Limestone|Age reasons|Vertebrate fauna (Kangaroo Well Local Fauna of Stirton et al. (1968)) includes marsupial taxa with biogeochronological utility, notably Balbaroo sp. Flannery, Archer and Plane, 1982, to which the following, but as yet unpublished discoveries may be added: cf. Neohelos tirarensis Stirton, cf. Pildra magnus Pledge, cf. Marlu kutjamarpensis Woodburne, Tedford and Archer and cf. Ektopodon stirtoni Pledge. In accordance with most recent calibrations of the continental land mammal biochronological scheme, unit is interpreted to be of Late Oligocene or Early Miocene age (see e.g. Stirton et al. (1968); Flannery et al. (1982); Woodburne et al. (1985, 1993); Rich (1991); Murray et al. (2000)).|16-MAY-23
37622|Ulta Limestone|Correlations|Marsupial biocorrelation and stage-of-evolution comparisons correlate unit with Etadunna Formation (Lake Eyre Basin); Namba Formation (Callabonna Basin) and older strata of Carl Creek Limestone (Karumba Basin) (e.g. Woodburne et al. 1985, Megirian 1992).|16-MAY-23
37622|Ulta Limestone|Proposed publication|Australian Journal of Earth Sciences or Alcheringa|16-MAY-23
37622|Ulta Limestone|References|79/04969; 83/23398; 98/29197;  **McMichael, D.F. 1968. Non-marine Mollusca from Tertiary rocks in northern Australia. Bureau of Mineral Resources, Geology and Geophysics, Australia, Bulletin 80: 133-159.; **Megirian, D. 1992. Interpretation of the Miocene Carl Creek Limestone, northwestern Queensland. The Beagle. Records of the Museum of Arts and Sciences 9(1): 219-248.; **Murray, P., Megirian, D., Rich, T., Plane, M., Black, K., Archer, M., Hand, S. and Vickers-Rich, P. (2000).Morphology, systematics, and evolution of the marsupial genus Neohelos Stirton (Diprotodontidae, Zygomaturinae). Museums and Art Galleries of the Northern Territory Research Report 6. 141pp. [http://www.nt.gov.au/cdsca/dam/publi.htm#magnt]; 98/29413;  **Rich, T.H. 1991. Monotremes, placentals, and marsupials: their record in Australia and its biases. In: Vickers-Rich, P., Monaghan, J.M., Baird, R.F. and Rich, T.H. (eds) Vertebrate palaeontology of Australasia. Pp 893-1070. Pioneer Design Studio and Monash University Publications Committee: Melbourne, Australia.; **Stirton, R.A., Tedford, R.H. and Woodburne, M.O. 1968. Australian Tertiary deposits containing terrestrial mammals. University of California Publications in Geological Sciences 77: 1-30. **Woodburne, M.O., MacFadden, B.J., Case, J.A., Springer, M.S., Pledge, N.S., Power, J.D., Woodburne, J.M., and Springer, K.B. 1993. Land mammal biostratigraphy and magnetostratigraphy of the Etadunna Formation (Late Oligocene) of South Australia. Journal of Vertebrate Palaeontology 13(4): 483-515. 89/26457|16-MAY-23
33650|Umutju Granite Suite|Name source|Umutju outstation, 25o 35' 31.4"S, 129o 27' 50.6"E, PETERMANN RANGES.|16-MAY-23
33650|Umutju Granite Suite|Unit history|Comprises part of the Musgrave-Mann Metamorphics, Olia Gneiss and unnamed metamorphosed granites of Forman (1966, 1972).|16-MAY-23
33650|Umutju Granite Suite|Constituents|Walytjatjata Granite, Puka Granite, Mantapayika Granite, unnamed charnockite and unnamed clinopyroxene granite.|16-MAY-23
33650|Umutju Granite Suite|Geomorphic expression|High steep rocky hills in the Mann Ranges with bouldery outcrop and smooth rock faces.  Lower scattered rocky hills and pavements north of the Mann Ranges.|16-MAY-23
33650|Umutju Granite Suite|Type section locality|Type localities for the respective constituent formations are given in their respective formal definitions.|16-MAY-23
33650|Umutju Granite Suite|Extent|Throughout the Mann Ranges and scattered low outcrops and rocky hills extending up to 30 km north of the Mann Ranges on PETERMANN RANGES, and an unknown extent into Western Australia and South Australia.|16-MAY-23
33650|Umutju Granite Suite|Thickness range|n/a|16-MAY-23
33650|Umutju Granite Suite|Lithology|Variably deformed and mylonitised porphyritic clinopyroxene- and hornblende-bearing granites. Primary mineralogy largely consisted of quartz, K-feldspar, plagioclase, clinopyroxene and Fe-Ti oxides, with or without biotite, and are overprinted by mylonitic fabrics defined by quartz, feldspar, hornblende, garnet, Fe-Ti oxides and biotite with or without clinopyroxene and sphene. Rounded K-feldspar and less abundant plagioclase phenocrysts are typically blue-grey in colour and 1-3 cm in diameter.  Localised high strain zones are migmatitic with coarse garnet and hornblende.|16-MAY-23
33650|Umutju Granite Suite|Depositional environment|n/a|16-MAY-23
33650|Umutju Granite Suite|Relationships and boundaries|Intrudes c.1550-1600 Ma granulite facies felsic and mafic gneisses, and c.1200 syn-tectonic charnockites. Intruded by 1078 Ma Alcurra Dyke Swarm and 800 Ma Amata Dyke Swarm. Truncated to the north by the Woodroffe Thrust and to the south by the Mann Fault.|16-MAY-23
33650|Umutju Granite Suite|Age reasons|Mesoproterozoic. Pb-Pb zircon evaporation ages of 1175 +/- 7 Ma for the Walytjatjata Granite (25o 56' 49.6"S, 129o 24' 34.2"E), 1172+/- 6 Ma for the unnamed clinopyroxene granite (25o 59' 33.9"S, 130o 1' 55.5"E), 1145 +/- 6 Ma for the Puka Granite (25o 1' 29.4"S, 129o 53' 13.5"E).|16-MAY-23
33650|Umutju Granite Suite|Correlations|Similar age, but geochemically distinct from the Pottoyu and Mantarurr Granite Suites and Walal Granite on PETERMANN RANGES.|16-MAY-23
33650|Umutju Granite Suite|Proposed publication|Petermann Ranges 1:250 000 geological mapsheet Explanatory Notes|16-MAY-23
33650|Umutju Granite Suite|Comments|Variably mylonitised and metamorphosed at ~10-13 kbars and 700-750?C during the c.560 Ma Petermann Orogeny.|16-MAY-23
33650|Umutju Granite Suite|References|Forman, D.J. (1966). The geology of the south-western margin of the Amadeus Basin, central Australia. Bureau of Mineral Resources Report 87. **Forman, D.J. (1972). Petermann Ranges, Northern Territory.  1:250 000 geological sheet and explanatory notes.  Bureau of Mineral Resources, Canberra, Australia.|16-MAY-23
33650|Umutju Granite Suite|Defn approved by|P Beier, PD Kruse, DN Young|16-MAY-23
26285|Unca Granite|Name source|After Unca Creek (640700mE 7490900mN, GDA94, Zone53) in Jervois Range 1:100 000 mapsheet, Northern Territory.|16-MAY-23
26285|Unca Granite|Unit history|First defined by Shaw et al (1985) as part of the undivided metamorphics of the Arunta Complex, and further defined and described by Freeman et al (1986) for the second edition Huckitta 1:250 000 mapsheet. Previously assigned as part of the Alarinjela Suite of Budd (1997).|16-MAY-23
26285|Unca Granite|Geomorphic expression|Low rubbly hills.|16-MAY-23
26285|Unca Granite|Type section locality|632496mE 7498959mN (GDA94, Zone53), approximately 6 km north-northeast of Jervois mineral field.|16-MAY-23
26285|Unca Granite|Extent|Limited to scattered outcrop over an approximately 18 km2 area north of the Jervois mineral field in the central Jervois Range 1:100 000 mapsheet.|16-MAY-23
26285|Unca Granite|Lithology|Granite; strongly weathered, leucocratic, inequigranular, fine-grained assemblage composed of quartz-K-feldspar-plagioclase. Rare brown biotite or chlorite after biotite. Minor muscovite is interpreted as secondary. Accessory titanite is locally apparent. Foliated.|16-MAY-23
26285|Unca Granite|Depositional environment|Continental margin environment, either arc cordillera or back arc basin, or derived from melting of pre-existing crust that formed in a continental margin environment.|16-MAY-23
26285|Unca Granite|Relationships and boundaries|Discordant intrusive contact with the Bonya Metamorphics and Attutra Metagabbro, with metre-scale dykes common in the latter. Unconformably overlain by the Neoproterozoic Oorabra Arkose and Elyuah Formation of the Georgina Basin. Exact nature of unit boundaries is not possible to define due to later tectonism and Cenozoic cover.|16-MAY-23
26285|Unca Granite|Identifying features|Homogenous strongly leucocratic granite with mica-poor assemblage. Biotite is absent to uncommon (<2% of mineral mode) and commonly replaced by chlorite. Accessory titanite is locally present. Strongly weathered with orange to pink weathered surface. Foliated.|16-MAY-23
26285|Unca Granite|Structure and Metamorphism|Penetrative grain shape foliation that is moderately- to well-developed and defined by elongate quartz and aligned biotite (or chlorite). Deformed during regional high-thermal gradient amphibolite facies metamorphism.|16-MAY-23
26285|Unca Granite|Age reasons|Interpreted to be synchronous with intrusion of 1780 ± 4 Ma Jericho Granite (LA-ICP-MS 207Pb/206Pb, Beyer et al in prep).|16-MAY-23
26285|Unca Granite|Correlations|Interpreted as co-magmatic and co-genetic with Thring and Jericho granites of the Fosters Suite, Baikal Supersuite based on similar geochemical and isotopic composition, and timing of structural fabric development.|16-MAY-23
26285|Unca Granite|Alteration and Mineralisation|Strongly bleached and silicified, locally hematite altered. Brecciated in outcrops that are in contact zones with unconformably overlying Georgina Basin stratigraphy. No known mineralisation.|16-MAY-23
26285|Unca Granite|Geochemistry|Weakly to moderately peraluminous I-type monzogranite.|16-MAY-23
26285|Unca Granite|Defn author|Anett Weisheit, Barry Reno, Eloise Beyer (Department of Primary Industry and Resources, Northern Territory Geological Survey) 27-JUN-2018.|16-MAY-23
26285|Unca Granite|Defn author|Anett Weisheit, Barry Reno, Eloise Beyer (Department of Primary Industry and Resources, Northern Territory Geological Survey)  27-JUN-2018|16-MAY-23
26285|Unca Granite|Proposed publication|Weisheit A, Reno BL and Beyer EE, in review. Jervois Range Special, Northern Territory. 1:100 000 geological map explanatory notes, 6152 and part 6252. Northern Territory Geological Survey, Darwin.|16-MAY-23
26285|Unca Granite|References|Beyer EE, Reno BL, Weisheit A, Whelan JA, Thompson JM, Meffre S and Woodhead JD, 2018. Summary of results. NTGS laser ablation ICP-MS U-Pb-Hf geochronology project: selected samples from JERVOIS RANGE 1:100 000 and TOBERMOREY 1:250 000 mapsheets, Aileron and Irindina provinces, January 2014 - December 2016. Northern Territory Geological Survey, Record 2018-001. **Beyer EE, Reno BL, Weisheit A, Meffre S, Thompson J and Woodhead JD, in prep. Summary of results. NTGS laser ablation ICP-MS U-Pb-Hf geochronology project: selected samples from JINKA and JERVOIS RANGE 1:100 000 mapsheet areas, Aileron and Irindina Provinces, Arunta Region, March 2015 - December 2017. Northern Territory Geological Survey, Darwin.  **Freeman MJ, Black LA, Offe LA, Senior BR, Shaw RD, Shergold JH, Simpson CJ, Walter MR, Warren RG, Donnellan N, Horsfall CJ, Laurie JR and Walley AM, 1986. Huckitta, Northern Territory (Second Edition). 1:250 000 geological map series, SF 53-11. Northern Territory Geological Survey, Darwin.   **Shaw RD, Warren RG and Freemann MJ, 1985. Stratigraphic definitions of named units in the Arunta Block, Northern Territory, 1979-82. Bureau of Mineral Resources, Australia, Report 260|16-MAY-23
18837|Undoolya Siltstone Member|Name source|Undoolya Gap (GR 41003745) in the Alice Springs 1:250 000 Sheet area.|16-MAY-23
18837|Undoolya Siltstone Member|Unit history|The Heavitree Quartzite has been previously undivided (Wells & others, 1968) except informally in the Arltunga Nappe Complex (Shaw & others, 1971).|16-MAY-23
18837|Undoolya Siltstone Member|Type section locality|Heavitree Gap (GR 3845 3745).|16-MAY-23
18837|Undoolya Siltstone Member|Extent|From Undoolya Gap (above) west to Jay Creek and then discontinuously as far as Ormiston Gorge in the Hermannsburg 1:250 000 Sheet area.|16-MAY-23
18837|Undoolya Siltstone Member|Thickness range|16 m.|16-MAY-23
18837|Undoolya Siltstone Member|Lithology|Purple and green interlaminated siltstone and shale and rare edgewise conglomerate. Several beds of fine-grained silty sandstone in the upper part.|16-MAY-23
18837|Undoolya Siltstone Member|Relationships and boundaries|Unconformably overlies crystalline rocks of the Sadadeen Range gneiss; an augen gneiss in the Hayes Metamorphic Complex. The Member is conformably overlain by the Temple Bar Sandstone Member of the Heavitree Quartzite.|16-MAY-23
18837|Undoolya Siltstone Member|Age reasons|Upper Proterozoic (see under 'Age' on Definition Temple Bar Sandstone Member)|16-MAY-23
18837|Undoolya Siltstone Member|Defn author|Wells A.T., 1976.|16-MAY-23
18837|Undoolya Siltstone Member|Proposed publication|BMR Microfiche Report 'Stratigraphic Definitions in the Arunta Block' Stewart & others, in preparation.|16-MAY-23
18837|Undoolya Siltstone Member|Defn Reference|80/20787|16-MAY-23
28281|Unimbra Sandstone|Name source|Unimbra Rockhole on the frew River at GR 112894, Hatches 1:100 000 Sheet area, Frew River 1:250 000 Sheet area.|16-MAY-23
28281|Unimbra Sandstone|Type section locality|In southeastern Bonney 1:100 000 Sheet area, Bonney Well 1:250 000 Sheet area: From GR 447367, where the formation overlies Kurinelli Sandstone, southwest to GR 443 355 (8 km west of Kurundi homestead, latitude 20o30'00"S, longitude 134o41'00"E), where it is overlain by Yeeradji Sandstone. The section consists of 750 m of mainly ;medium-grained quartz arenite, with coarse to gritty and pebbly beds in the lower half.|16-MAY-23
28281|Unimbra Sandstone|Extent|Throughout the Davenport Province - eastern and central parts of Bonney Well, southwestern part of Frew River, northwestern part of Elkedra, and northeastern part of Barrow Creek 1:250 000 Sheet areas.|16-MAY-23
28281|Unimbra Sandstone|Thickness range|Ranges from 120 m at Unimbra Rockhole to over 1500 m in eastern Hatches and western Hanlon 1:100 000 Sheet areas.|16-MAY-23
28281|Unimbra Sandstone|Lithology|Ridge-forming, aminly medium;-grained, quartz-rich to sublithic and subarkosic arenite; gritty and pebbly to conglomeratic beds common, particularly in the west; fine-grained clayey and micaceous arenite partings common; trough -cross-bedding very widespread.|16-MAY-23
28281|Unimbra Sandstone|Relationships and boundaries|Unconformable on Warramunga Group in north; conformable and possibly disconformable on the Mia Mia Volcanics, Treasure Volcanics, Epenarra Volcanics, Kurinelli Sandstone, and Taragan Sandstone of the Ooradidgee Subgroup of the Hatches Creek Group; also interfingers locally with upper parts of the Treasure Volcanics and Epenarra Volcanics. Overlain conformably by the Yeeradgi Sandstone and Newlands Volcanics. Intruded by some sill-like bodies of granophyre and rare dolerite. More quartzose then underlying Kurinelli Sandstone and overlying Yeeradgi Sandstone, less pebbly than underlying Taragan Sandstone.|16-MAY-23
28281|Unimbra Sandstone|Age reasons|Younger than 1870 m.y. - U-Pb zircon age of volcanics within the Warramunga Group unconformably underlying the Hatches Creek Group. Older than 1640 m.y. - Rb-Sr whole-rock age of granite intruding the Hatches Creek Group.|16-MAY-23
28281|Unimbra Sandstone|Defn author|Blake D.H. Stewart A.J., Sweet I.P., Wyche S., 1985|16-MAY-23
28281|Unimbra Sandstone|Proposed publication|BMR Report 257|16-MAY-23
28281|Unimbra Sandstone|Comments|Remarks: One of three major ridge-forming units in the Davenport Province. Basal formation of the Wauchope Subgroup of the Hatches Creek Group.|16-MAY-23
28281|Unimbra Sandstone|Defn Reference|86/25362|16-MAY-23
28281|Unimbra Sandstone|Proposer|Sweet I.P.|16-MAY-23
28281|Unimbra Sandstone|Resdate|07-OCT-1981|16-MAY-23
26967|Uniya Formation|Name source|First Catholic mission in Daly River District. West bank of Daly River, a few miles downstream from present Mission (Pye, 1978). Daly River 1:100 000 (5070).|16-MAY-23
26967|Uniya Formation|Unit history|Formerly assigned in part to Stray Creek Sandstone, Buldiva Sandstone, Tolmer Group and in part to Witch Wai Conglomerate in Daly River 1:100 0000 (White and othes, 1959). Formerly assigned to Jarong Conglomerate in Wingate Mountains 1:100 000 (Pontifex and Mendum, 1972).|16-MAY-23
26967|Uniya Formation|Type section locality|The holostratotype is in the headwaters of Hayward Creek and lies along a line between AMG 968960 (latitude 13o35'46", longitude 130o49'24") and AMG 985950 (latitude 13o36'20", longitude 130o50'2"), Daly River 1:100 000. The parastratotype is at a hill 3 km SE of Collah Waterhole, AMG 084079 (latitude 14o23', longitude 130o56'34") Wingate Mountains 1:100 000. An area has to be given for the holostratotype because no vertical sections showing the full range of lithologies in the Formation are exposed.|16-MAY-23
26967|Uniya Formation|Extent|Crops out intermittently across an area of about 25 sq km in the headwaters of Hayward Creek, and at a small exposure in the southeast corner of the Daly River 1:100 000. Poorly exposed in mesas in Jarong Springs - Collah Waterhole area, and well exposed south of Collah Waterhole near AMG 084079 (Wingate Mountains 1:100 000).|16-MAY-23
26967|Uniya Formation|Thickness range|Varies greatly. Ranges 0-30 m in holostratotype. Ranges 0-60 in parastratotype. 137 m of tillite encountered in a diamond drillhole at AMG 059082 (latitude 14o23'20", longitude 130o54'34").|16-MAY-23
26967|Uniya Formation|Lithology|Holostratotype: The tillite includes massive unsorted tillite, glaciofluvial sandstones and minor conglomerate, varved lake deposits with dropstones, poorly bedded mudstones/fine sandstones with massive slumping and soft sediment deformation. Erratics are composed of Early Proterozoic metasediments, Early Proterozoic granites and gneisses, Late Proterozoic quartzites and carbonates. Proportions of lithologies cannot be estimated because of lateral facies changes and inadequate exposure. Parastratotype: Tillite, glaciolacustrine arenites and mudstones, glaciofluvial arenites, tillite and boulder conglomerate approximately 70%, glaciolacustrine and glaciofluvial sediments approximately 30%.|16-MAY-23
26967|Uniya Formation|Relationships and boundaries|Overlies Stray Creek Member of Buldiva Sandstone and Hinde Dolomite (Tolmer Group) on Daly River 1:100 000, and Saddle Creek Formation and Angalarri Siltstone (Auvergne Group) on Wingate Mountains 1:100 000, with a small angular unconformity. Overlain by Antrim Plateau Volcanics - relationship not definite but probably unconformable.|16-MAY-23
26967|Uniya Formation|Age reasons|Older than Early Cambrian (Antrim Plateau Volcanics), younger than Middle-Late Proterozoic. Post-dates Giants Reef Fault. Presumed very Late Proterozoic by correlation with other glacial deposits in the Victoria River and Kimberley regions (about 700 Ma) (Sweet, 1977).|16-MAY-23
26967|Uniya Formation|Proposed publication|Dundas D.L., Edgoose C.J., Fahey G.M., Fahey J.E., in prep. - Explanatory Notes (for) Daly River (5070). Northern Territory Geological Survey 1:100 000 Geological map series. Northern Territory Government Printer, Darwin.|16-MAY-23
33487|Utanta Granite|Name source|Utanta - Aboriginal name for Butler Dome, 25o 38' 10.8"S, 130o 14' 13.9"E, PETERMANN RANGES.|16-MAY-23
33487|Utanta Granite|Unit history|Corresponds to an unnamed metamorphosed granite of Forman (1966, 1972).|16-MAY-23
33487|Utanta Granite|Constituents|Nil. Forms part of the Mantarurr Granite Suite.|16-MAY-23
33487|Utanta Granite|Geomorphic expression|Rubbly slopes underlying the western quartzite scarps of Butler Dome, leading down into low bouldery rounded hills.|16-MAY-23
33487|Utanta Granite|Type section locality|In creek 5 km NNW of Butler Dome 25o 36' 1.2"S, 130o 13' 25.9"E.|16-MAY-23
33487|Utanta Granite|Extent|Occurs over approximately 4 x 10 km of continuous outcrop on the western side of Butler Dome.|16-MAY-23
33487|Utanta Granite|Thickness range| n/a|16-MAY-23
33487|Utanta Granite|Lithology|Coarsely porphyritic biotite granite, conspicuously more felsic than other granites in Mantarurr Suite.  Contains K-feldspar phenocrysts up to 3cm in diameter in a coarse grained matrix in which mafic minerals occur as coarse clusters of biotite and Fe-Ti oxides with minor muscovite, garnet and allanite.  Fluorite is locally present.|16-MAY-23
33487|Utanta Granite|Depositional environment| n/a|16-MAY-23
33487|Utanta Granite|Relationships and boundaries|Few clear relationships.  Has a sharp intrusive contact with the Wala Wuru Granite but with no clear timing relationship.|16-MAY-23
33487|Utanta Granite|Age reasons|Mesoproterozoic. Correlated (on basis of geochemical similarity) with Kulu Granite which has a SHRIMP U-Pb zircon age of c.1168+/-14 Ma (M. Fanning, pers. comm.)|16-MAY-23
33487|Utanta Granite|Correlations|Geochemically and mineralogically similar to Wala Wuru Granite, Foster Cliff Granite and Kulu Granite.  Similar age, but geochemically distinct from the Pottoyu and Umutju Complexes and Walal Granite on PETERMANN RANGES.|16-MAY-23
33487|Utanta Granite|Comments|The Butler Dome Granite is strongly enriched in Th and therefore defines a strong radiometric anomaly.  Deformed and metamorphosed during the c.560 Ma Petermann Orogeny at ~6kbars and 600-650?C.|16-MAY-23
33487|Utanta Granite|References|Forman, D.J. (1966). The geology of the south-western margin of the Amadeus Basin, central Australia. Bureau of Mineral Resources Report 87. **Forman, D.J. (1972). Petermann Ranges, Northern Territory.  1:250 000 geological sheet and explanatory notes.  Bureau of Mineral Resources, Canberra, Australia.|16-MAY-23
19019|Utopia Quartzite|Name source|After 'Utopia' Station which covers part of the outcrop area. 'Utopia' Station is in the northeastern part of the Alcoota 1:250 000 Sheet area SF 53-10 AMG.|16-MAY-23
19019|Utopia Quartzite|Type section locality|AT the southwestern end of an unnamed range across syncline centered on 4337519, Zone 53 AMG (metric). Range is 11 km west of 'Delmore Downs' homestead. Syncline also type area of Ledan Schist.|16-MAY-23
19019|Utopia Quartzite|Extent|From Ledan Peak east to beyond the Sheet border.|16-MAY-23
19019|Utopia Quartzite|Lithology|Quartzite, granule conglomerate, ironstone lenses.|16-MAY-23
19019|Utopia Quartzite|Relationships and boundaries|Unconformably underlies the Grant Bluff Formation and the Central Mount Stuart Beds. Disconformably overlies the Ledan Schist. Contacts: Granule conglomerate common at base. Contacts well exposed in type area and also at 4638, 75277.|16-MAY-23
19019|Utopia Quartzite|Identifying features|Quartzite pale brown. Quartzite in Ledan Schist is typically blue-black.|16-MAY-23
19019|Utopia Quartzite|Correlations|Tentative correlations: Grouped with the Ledan Schist as equivalents of the Hatches Creek Group and the Reynolds Range Group.|16-MAY-23
19019|Utopia Quartzite|Proposed publication|BMR Report|16-MAY-23
24549|Vaddingilla Formation|Name source|Vaddingilla Rockhole on Yaddanilla Creek at GR 677983, Hanlon 1:100 000 Sheet area, Frew River 1:250 000 Sheet area.|16-MAY-23
24549|Vaddingilla Formation|Type section locality|5 km NW of Vaddingilla Rockhole (latitude 20o49'00"S, longitude 135o39'10"E); from GR 632020, where the formation conformably overlies Canulgerra Sandstone, NE to GR 648034, where it is overlain conformably by Yaddanilla Sandstone. The sequence dips 20o-25o ENE, and is about 800 m thick. Here as elsewhere, much of the formation is concealed beneath surficial Cainozoic sediments.|16-MAY-23
24549|Vaddingilla Formation|Extent|Crops out only in the western part of Hanlon 1:100 0000 Sheet area.|16-MAY-23
24549|Vaddingilla Formation|Thickness range|About 800 m.|16-MAY-23
24549|Vaddingilla Formation|Lithology|Recessive siltstone, shale, and friable arenite.|16-MAY-23
24549|Vaddingilla Formation|Relationships and boundaries|Conformable on Canulgerra Sandstone; overlain conformably by Yaddanilla Sandstone. Boundaries taken at abrupt topographic changes from recessive beds to underlying and overlying ridge-forming units.|16-MAY-23
24549|Vaddingilla Formation|Age reasons|Younger than 1870 m.y. - U-Pb zircon age of volcanics in the Warramunga Group overlain unconformably by the Hatches Creek Group. Older than 1640 m.y. - Rb-Sr whole-rock approximate age for granite intruding the Hatches Creek Group.|16-MAY-23
24549|Vaddingilla Formation|Defn author|Blake D.H., Stewart A.J., Sweet I.P., Wyche S., 1985|16-MAY-23
24549|Vaddingilla Formation|Proposed publication|BMR Report 257|16-MAY-23
24549|Vaddingilla Formation|Comments|Remarks: Recessive unit between two ridge-forming formations. Part of the Hanlon B44Subgroup fo the Hatches Creek Group.|16-MAY-23
24549|Vaddingilla Formation|Defn Reference|86/25362|16-MAY-23
24549|Vaddingilla Formation|Proposer|Wyche S.|16-MAY-23
24549|Vaddingilla Formation|Resdate|07-OCT-1981|16-MAY-23
19074|Velkerri Formation|Name source|After Velkerri Creek, in southern Flying Fox northwestern URAPUNGA, which flows into Maiwok Creek at about latitude -14.38° longitude 133.72° (MGA 53K 362000mE 8410000mN).|16-MAY-23
19074|Velkerri Formation|Unit history|Lower part of the Cobanbirini Formation of Paine (1963) and Smith (1964). The name Cobanbirini Formation is superseded and abandoned in most mapsheet areas, except in TANUMBIRINI, where the vintage of mapping (Paine 1963) is First Edition and precedes subdivision of the unit. Parent is the Roper Group of the Maiwok Subgroup (formerly the basal unit of the Maiwok Subgroup prior to inclusion of the Bessie Creek Sandstone and Corcoran Formation in the Subgroup by Abbott and Sweet (2001).|16-MAY-23
19074|Velkerri Formation|Constituents|Threefold subdivision into Kalala Member, Amungee Member and Wyworrie Member, in ascending stratigraphic order (Munson and Revie 2018).|16-MAY-23
19074|Velkerri Formation|Geomorphic expression|Recessive unit that is poorly exposed, except as rare small outcrops of buff- to white-weathering laminated siltstone and mudstone, or fragments of this lithology in skeletal soil. Present in scarp slopes beneath Moroak Sandstone and also underlies extensive plains.|16-MAY-23
19074|Velkerri Formation|Type section locality|Poor exposure precludes nomination of a surface type section. Abbott et al (2001) nominated a complete intersection of the formation in drillhole BMR Urapunga-4 (Sweet and Jackson 1986), from 372 m depth (base) to 42 m depth (top) as type section. This intersection includes 8.5 m of Kalala Member (372-363.3 m depth); 233 m of Amungee Member (363.5-130.5 m depth); and 88.5 m of Wyworrie Member (130.5-42 m depth; see Munson and Revie 2018). Urapunga-4 is located in central Chapman 1:100k mapsheet in southern Urapunga 1:250k mapsheet (MGA94 53K 423949mE 8374386mN; latitude -14.7032° longitude 134.2936°). Core is housed in the Geoscience Australia Repository in Canberra.|16-MAY-23
19074|Velkerri Formation|Extent|Exposed and in subsurface in Katherine, Urapunga, Roper River, Hodgson Downs and Mount Young 1:250k mapsheets. Subsurface in Larrimah, Tanumbirini, Beetaloo and Bauhinia Downs 1:250k mapsheets. Exposed in Tanumbirini 1:250k mapsheet as Cobanbirini Formation (in part).|16-MAY-23
19074|Velkerri Formation|General description|Dominantly fine-grained unit consisting of massive to laminated, grey-green and dark grey to brown-black (carbonaceous) claystone; interlaminated to thinly interbedded claystone, pale grey siltstone, and minor, light grey fine-grained sandstone; and rare, thin dolomitised limestone. Rocks are generally laminated, but intervals that are structureless or characterised by abundant convoluted laminae are common. Calcite nodules and veins, and pyrite are present throughout. Laminae and thin intervals of sandstone may contain glauconite.|16-MAY-23
19074|Velkerri Formation|Thickness range|330 m thick. Complete drillhole intersections range from a minimum of 330 m in Urapunga-4 to a maximum of 1482 m in Santos Tanumbirini-1. Other significant intersections include 555 m in POG Alexander-1; >837.93 m in POG Altree-2; >870 m in Origin Amungee NW-1; >734.02 m Pangaea Birdum Creek-1; >449 m in POG Broadmere-1; >776.5 m in Origin Kalala S-1; 501 m in POG Lady Penrhyn-1; >879.2 in POG McManus-1; 499 m in POG Scarborough-1; 754.42 m in POG Sever-1; >582.6 m in Pangaea Tarlee S-3; >601.3 m in POG Walton-2; and >520.04 m in Pangaea Wyworrie-1 (Munson and Revie 2018: table 1).|16-MAY-23
19074|Velkerri Formation|Lithology|Interlaminated to thinly interbedded, grey-green to dark grey claystone, pale grey siltstone and minor, light grey fine-grained sandstone, with intervals of massive to laminated, grey-green and dark grey to brown-black (carbonaceous) claystone.|16-MAY-23
19074|Velkerri Formation|Depositional environment|Subtidal, sub-wave base, and generally quiet marine with regular current activity, consistent with periodic turbidity currents (Munson 2016 and references therein).|16-MAY-23
19074|Velkerri Formation|Relationships and boundaries|Gradational contact, marked by interbedded shale and fine-grained sandstone, between underlying Bessie Creek Sandstone and overlying Kalala Member (base Velkerri Formation). Conformable upper contact between Wyworrie Member and Moroak Sandstone is sharp and erosive.|16-MAY-23
19074|Velkerri Formation|Identifying features|Recessive mudrock-dominated succession clearly distinguishes Velkerri Formation from resistant, coarser-grained underlying Bessie Creek and overlying Moroak sandstones.|16-MAY-23
19074|Velkerri Formation|Structure and Metamorphism|Unmetamorphosed. Flat-lying, or gentle to open folds, and/or brittle faults with minor displacements in most areas. More intense deformation (thrusts, shears, close to tight folds) in vicinity of major fault zones.|16-MAY-23
19074|Velkerri Formation|Age reasons|Mesoproterozoic. Maximum deposition age constrained by SHRIMP U-Pb zircon ages of 1492 ± 4 Ma and 1493 ± 4 Ma from rare tuffs in Showell Member of underlying Mainoru Formation (Jackson et al 1999), and by 1312.9 ± 0.7 Ma age for Derim Derim Dolerite, which intrudes Velkerri Formation (Collins et al 2018). Organic-rich shales from Amungee Member have been dated by Re-Os method at 1417 ± 29 Ma (A organofacies) and 1361 ± 21 Ma (C Organofacies; Creaser and Kendall 2007, Kendall et al 2009).|16-MAY-23
19074|Velkerri Formation|Correlations|Probably equivalent to Lake Woods beds of Renner Group of Tomkinson Province (Hussey et al 2001), Tijunna Group (in part) of Birrindudu Basin; and Mullera Formation (in part) of South Nicholson Basin (Munson 2016).|16-MAY-23
19074|Velkerri Formation|Alteration and Mineralisation|Some in situ weathering of minerals, including alteration of labile minerals to clays. Organic-rich intervals have proven source rock potential and are prospective for unconventional petroleum.|16-MAY-23
19074|Velkerri Formation|Geophysical Expression|Kalala Member: gamma log shows overall gentle upward-decline in values, whereas resistivity log is low and mostly flat. Amungee Member: three distinctive excursions in gamma and resistivity logs correspond to organic shale facies (informally named organofacies A¿C, in ascending order). Wyworrie Member: distinctive gamma and resistivity logs are both relatively flat.|16-MAY-23
19074|Velkerri Formation|Geochemistry|Kalala Member: TOC generally lean, organic-rich mudrock intervals absent, phosphate, carbonate, and redox-sensitive trace elements (eg, U, Ni, V, Mo, Zn, Cu, Tl) all have typically low values, slightly higher towards base, in comparison to overlying Amungee Member. Log values for some oxides and heavy mineral trace elements (eg, Al2O3, K2O, Sc, Nb, Th, Sn, Cr) are elevated relative to Amungee Member. Amungee Member: TOC and carbonate content appreciably higher throughout Amungee Member than in Kalala and Wyworrie members. Organofacies A¿C well defined by prominent excursions in TOC, phosphate, and redox-sensitive trace elements; and by lower log values for some oxides and heavy mineral trace elements. Wyworrie Member: TOC appreciably lower than in Amungee Member, but slightly higher than in Kalala Member; organic-rich mudrock intervals absent. Phosphate, carbonate, and redox-sensitive trace elements all have typically low values compared to Amungee Member, and are higher towards base. Log values for some oxides and heavy mineral trace elements are elevated relative to Amungee Member.|16-MAY-23
19074|Velkerri Formation|Defn author|IP Sweet, after Dunn 1963 (updated TJ Munson, D Revie) April 2018.|16-MAY-23
19074|Velkerri Formation|Proposed publication|Abbott ST, Sweet IP, Plumb KA, Young DN, Cutovinos A, Ferenczi PA, Brakel A and Pietsch BA, 2001. Roper Region: Urapunga and Roper River Special, Northern Territory (Second Edition). 1:250 000 geological map series explanatory notes, SD 53-10, 11. Northern Territory Geological Survey and Geoscience Australia (National Geoscience Mapping Accord). **Munson TJ and Revie D, 2018. Stratigraphic subdivision of Velkerri Formation, Roper Group, McArthur Basin, Northern Territory. Northern Territory Geological Survey, Record 2018-006.|16-MAY-23
19074|Velkerri Formation|Comments|Velkerri Formation is notable for its organic-rich intervals which are prime petroleum source rocks and unconventional petroleum targets (Revie 2017 and references therein).  Conformable upper contact between Wyworrie Member and Moroak Sandstone is sharp and erosive in some wells (eg BMR Urapunga-4; Abbott and Sweet 2001), and gradational in other wells (eg Alexander-1; Barberis and Ledlie 1988). Palynomorphs have been recovered from Kalala and Wyworrie members in drillholes Altree-2 and McManus-1 (Grey 2015).|16-MAY-23
19074|Velkerri Formation|References|Abbott ST and Sweet IP, 2001. Measured sections and drillcore logs from the Urapunga and Roper River 1:250 000 mapsheets, Northern Territory. Northern Territory Geological Survey, Technical Report 2001 004. **Collins A, Farkas J, Glorie S, Cox G, Blades ML, Yang Bo, Nixon A, Bullen M, Foden JD, Dosseto A, Payne JL, Denyszyn S, Edgoose CJ, Close D, Munson TJ, Menpes S, Spagnuolo S, Gusterhuber J, Sheridan M, Baruch-Jurado E and Close D, 2018. Orogens to oil: government-industry-academia collaboration to better understand the greater McArthur Basin: in Annual Geoscience Exploration Seminar (AGES) Proceedings, Alice Springs, Northern Territory, 20¿21 March 2018. Northern Territory Geological Survey, Darwin. 49-51. **Creaser RA and Kendall B, 2007. Re-Os geochronology of organic-rich shales; Placing absolute time pins in ancient sedimentary basins. American Geophysical Union, Fall Meeting 2007, abstract #V31G-01. **Dunn PR, 1963. Hodgson Downs, Northern Territory (First Edition). 1:250 000 geological map series and explanatory notes, SD 53-14. Bureau of Mineral Resources, Australia, Canberra. **Grey K, 2015. Mesoproterozoic biostratigraphic correlation in the Beetaloo Sub-basin, Northern Territory, Australia and potential for correlation with other northern Australian basins: in 'Annual Geoscience Exploration Seminar (AGES) 2015. Record of Abstracts.' Northern Territory Geological Survey, Record 2015-002. **Hussey KJ, Beier PR, Crispe AJ, Donnellan N and Kruse PD, 2001. Helen Springs, Northern Territory (Second Edition). 1:250 000 geological map series and explanatory notes, SE 53-10. Northern Territory Geological Survey, Darwin. **Jackson MJ, Sweet IP, Page RW and Bradshaw BE, 1999. The South Nicholson and Roper Groups: Evidence for the early Mesoproterozoic Roper Superbasin: in Bradshaw BE and Scott DL (editors). 'Integrated basin analysis of the Isa Superbasin using seismic, well-log and geopotential data: an evaluation of the economic potential of the northern Lawn Hill Platform.'  Australian Geological Survey Organisation Record 1999/19 (CD ROM), 36-45. **Kendall B, Creaser RA, Gordon GW and Anbar AD, 2009. Re-Os and Mo isotope systematics of black shales from the Middle Proterozoic Velkerri and Wollogorang Formations, McArthur Basin, northern Australia. Geochimica et Cosmochimica Acta 73, 2534-2558. **Munson TJ, 2016. Sedimentary characterisation of the Wilton package, greater McArthur Basin, Northern Territory. Northern Territory Geological Survey, Record 2016-003. **Munson TJ and Revie D, 2018. Stratigraphic subdivision of Velkerri Formation, Roper Group, McArthur Basin, Northern Territory. Northern Territory Geological Survey, Record 2018-006. **Paine AGL, 1963. Tanumbirini, Northern Territory (First Edition). 1:250 000 geological map series and explanatory notes, SE 53-2. Bureau of Mineral Resources, Canberra, Australia. **Revie D, 2017. Volumetric resource assessment of the lower Kyalla and middle Velkerri formations of the McArthur Basin: in Annual Geoscience Exploration Seminar (AGES) Proceedings, Alice Springs, Northern Territory, 28-29 March 2017. Northern Territory Geological Survey, Darwin. **Smith JW, 1964. Bauhinia Downs, Northern Territory (First Edition). 1:250 000 geological map series and explanatory notes, SE 53-03. Bureau of Mineral Resources, Australia, Canberra. **Sweet IP and Jackson MJ, 1986. BMR stratigraphic drilling in the Roper Group, Northern Territory, 1985. Bureau of Mineral Resources, Australia, Record 1986/19.|16-MAY-23
24629|Wagait Granite|Name source|Wagait Aboriginal Land, Fog Bay and Anson 1:100 000 Sheet areas, where the type area occurs.|16-MAY-23
24629|Wagait Granite|Unit history|Previously described as undifferentiated Litchfield Complex granite e.g. Walpole and others (1968). Named Wagait Granite by Berkman (1980). Described in Fahey and Edgoose (1986).|16-MAY-23
24629|Wagait Granite|Type section locality|Anson 1:100 000 Sheet area 4971. Reference FL 410498. Latitude 13o06'42", longitude 130o18'.|16-MAY-23
24629|Wagait Granite|Extent|Anson, Fog Bay and Greenwood 1:100 000 Sheet areas, Northern Territory. Occurs as sporadic outcrops over about 2700 km2.|16-MAY-23
24629|Wagait Granite|Lithology|Hornblende granite, hornblende granodiorite, adamellite, listed in order of decreasing abundance.|16-MAY-23
24629|Wagait Granite|Relationships and boundaries|Intrudes Early Proterozoic Fog Bay and Welltree Metamorphics, contacts concealed. Overlain by Middle Proterozoic Moyle River Formation and Early Permian sediments. Intruded by Murrenja Dolerite, presumed Middle-Late Proterozoic.|16-MAY-23
24629|Wagait Granite|Age reasons|1852 +/- 33 Ma. Rb/Sr date in Page and others (1985).|16-MAY-23
24629|Wagait Granite|Proposed publication|Greenwood, NT 1:100 000 Explanatory Notes 1987|16-MAY-23
24629|Wagait Granite|Comments|Mention Map legend|16-MAY-23
24629|Wagait Granite|Name first published by|Needham R.S., Stuart-Smith P.G., Knight C.P., Pietch B.A., Dundas D.|16-MAY-23
24629|Wagait Granite|Proposer|Edgoose C.J., Hickey S.H.|16-MAY-23
24629|Wagait Granite|Resdate|01-01-1979|16-MAY-23
24629|Wagait Granite|Reserved? Yes/No|Berman D.A.|16-MAY-23
33488|Wala Wuru Granite|Name source|Wala Wuru, Aboriginal name for Stevenson Peak, 25o 29' 55.1"S, 130o 10' 48.2"E, PETERMANN RANGES.|16-MAY-23
33488|Wala Wuru Granite|Unit history|Comprises part of the Olia Gneiss of Forman (1966, 1972).|16-MAY-23
33488|Wala Wuru Granite|Constituents|Nil. Forms part of the Mantarurr Granite Suite.|16-MAY-23
33488|Wala Wuru Granite|Geomorphic expression|Low outcrops and rounded rocky hills.  Rubbly slopes underlying quartzite scarps of Stevenson Peak region and Butler Dome.|16-MAY-23
33488|Wala Wuru Granite|Type section locality|1km south-southeast of Stevenson Peak 25o 30' 21"S, 130o 11' 2.8"E.|16-MAY-23
33488|Wala Wuru Granite|Extent|Outcrops in the vicinity of Stevenson Peak and up to 6 km to the south and 5km to the east, and on the eastern side of Butler Dome on PETERMANN RANGES.|16-MAY-23
33488|Wala Wuru Granite|Thickness range|n/a|16-MAY-23
33488|Wala Wuru Granite|Lithology|Foliated biotite granite with large rectangular white to pale orange K-feldspar phenocrysts in a fine to medium grained biotite-rich matrix. Phenocrysts are typically 1-3cm in diameter.  The mineralogy typically comprises quartz, K-feldspar, plagioclase, biotite, sphene, ilmenite and epidote.|16-MAY-23
33488|Wala Wuru Granite|Depositional environment|n/a|16-MAY-23
33488|Wala Wuru Granite|Relationships and boundaries|Has sharp intrusive contacts with the Utanta and Foster Cliff granites.|16-MAY-23
33488|Wala Wuru Granite|Age reasons|Mesoproterozoic. Correlated with Kulu Granite which has a SHRIMP U-Pb zircon age of c.1168 ? 14 Ma (M. Fanning, pers. comm.)|16-MAY-23
33488|Wala Wuru Granite|Correlations|Geochemically and mineralogically similar to other units of the Mantarurr Granite Suite (Utanta Granite, Foster Cliff Granite and Kulu Granite).  Similar age, but geochemically distinct from the Pottoyu and Umutju Suites and Walal Granite on PETERMANN RANGES.|16-MAY-23
33488|Wala Wuru Granite|Comments|Variably deformed and metamorphosed to amphibolite facies during the c.560 Ma Petermann Orogeny.|16-MAY-23
33488|Wala Wuru Granite|References|Forman, D.J. (1966). The geology of the south-western margin of the Amadeus Basin, central Australia. Bureau of Mineral Resources Report 87. **Forman, D.J. (1972). Petermann Ranges, Northern Territory.  1:250 000 geological sheet and explanatory notes.  Bureau of Mineral Resources, Canberra, Australia.|16-MAY-23
72423|Walabanba Member|Name source|Walabanba Hills in vicinity of 53K 302500mE 7560300Mn, northwestern ANNINGIE|16-MAY-23
72423|Walabanba Member|Unit history|None|16-MAY-23
72423|Walabanba Member|Geomorphic expression|Locally forms prominent hills, but generally poorly outcropping.|16-MAY-23
72423|Walabanba Member|Type section locality|Walabanba Hills, particularly in vicinity of 303000mE 7600000mN (21o41.5'S 133o06'E) in ANNINGIE.|16-MAY-23
72423|Walabanba Member|Extent|Outcrops over an area of about 40 km2 in Walabanba Hills and about 15 km2 to north of Old Mount Peake centred on 284500mE 7624000m, and at 294250mE 7669500mN in MOUNT PEAKE. The unit also outcrops locally in southern LANDER RIVER. Interpretation of geophysical data, primarily airborne magnetic, indicate that it is a component of the Lander Rock Formation succession throughout northern and eastern MOUNT PEAKE, and LANDER RIVER south of Wiso Basin.|16-MAY-23
72423|Walabanba Member|Thickness range|Polydeformation precludes precise determination, but estimated to be <= 850 m.|16-MAY-23
72423|Walabanba Member|Lithology|Alternating metapelite (typically with a well developed slaty cleavage) and metapsammite representing an original succession of siltstone and crossbedded quartz arenite, latter having localised heavy mineral laminations; and layer-parallel ortho-amphibolite. Pelitic rocks locally more schistose, particularly proximal to granite contacts where they contain large retrogressed andalusite porphyroblasts. Psammitic rocks similarly hornfelsed proximal to granite, and contain small proportion of plagioclase, microcline, biotite, muscovite and titanite.|16-MAY-23
72423|Walabanba Member|Depositional environment|Shallow marine.|16-MAY-23
72423|Walabanba Member|Relationships and boundaries|Contacts with immediately under- and overlying intervals of Lander Rock Formation not generally exposed. In Walabanba Hills the unit is locally concordant with stratiform metabasic rocks within undivided upper Lander Rock Formation. Poorly or non-outcropping non-magnetic intervals of Lander Rock Formation metasedimentary rocks also bound the unit, and separate it from underlying Anningie Member.  Intruded by Esther Granite and unnamed gabbro and dolerite.|16-MAY-23
72423|Walabanba Member|Structure and Metamorphism|Polydeformed with generally moderately dipping but locally overturned strata.|16-MAY-23
72423|Walabanba Member|Age reasons|Late Orosirian. Maximum age of sedimentation of ~1863 Ma based on average of youngest coherent group of zircons (1863 ± 5 Ma); youngest zircon is 1822 ± 56 Ma (Claoué-Long et al in press). Intruded by 1789 ± 6 Ma (Cross et al 2005) Esther Granite.|16-MAY-23
72423|Walabanba Member|Correlations|Probably partially correlates with Woodalla and Mount Stafford Members of Lander Rock Formation but comprises more proximal, shallow marine sedimentation in contrast with these deep-water (turbiditic) metasedimentary rocks. Correlated with part of both Bullion Schist and Ooradidgee Group.|16-MAY-23
72423|Walabanba Member|References|Claoué-Long JC, Edgoose C and Worden KE, in press. A correlation of Arunta Region stratigraphy in central Australia. Precambrian Research.Cross A, Claoué-Long JC, Scrimgeour IR, Crispe A and Donnellan N, 2005. Summary of results. Joint NTGS-GA geochronology project: northern Arunta and Tanami regions 2000-2003. Northern Territory Geological Survey, Record 2005-003.|16-MAY-23
33656|Walal Granite|Name source|Walal claypan, 25o 59' 34.1"S, 130o 15' 13.9"E, PETERMANN RANGES.|16-MAY-23
33656|Walal Granite|Unit history|Comprises part of the Musgrave-Mann Metamorphics of Thomson (1969) and Forman (1972).|16-MAY-23
33656|Walal Granite|Constituents|Nil.|16-MAY-23
33656|Walal Granite|Geomorphic expression|Low rocky hills and outcrops with boulders and tors.|16-MAY-23
33656|Walal Granite|Type section locality|In low outcrops in the vicinity of Walal claypan and low hills extending 6 km to the east.  Extent in South Australia is unknown.|16-MAY-23
33656|Walal Granite|Extent|In low outcrops in the vicinity of Walal claypan and low hills extending 6 km to the east.  Extent in South Australia is unknown.|16-MAY-23
33656|Walal Granite|Thickness range| n/a|16-MAY-23
33656|Walal Granite|Lithology|Foliated porphyritic clinopyroxene granite and granodiorite with coarse euhedral to subhedral purple-brown phenocrysts of K-feldspar.  Primary clinopyroxene and hornblende is largely replaced by metamorphic garnet, biotite and hornblende. The porphyritic granite and granodiorite is intruded by a medium grained equigranular granite, also containing purple K-feldspar, with <5% mafic minerals comprising garnet, biotite, hornblende and clinopyroxene.|16-MAY-23
33656|Walal Granite|Depositional environment| n/a|16-MAY-23
33656|Walal Granite|Relationships and boundaries|Intrudes and contains xenoliths of c.1550-1600 Ma granulite facies felsic gneisses. Intruded by mafic dykes of uncertain age (probably 1080 or 800 Ma) but also contains minor mafic xenoliths|16-MAY-23
33656|Walal Granite|Age reasons|Mesoproterozoic. No definitive age but probably intruded between 1180-1140 Ma, synchronous with Umutju Suite.  Alternatively it may be a similar age to the 1070 Ma Angatja Suite.|16-MAY-23
33656|Walal Granite|Correlations|Probably a similar age, but geochemically distinct from the Pottoyu, Umutju and Mantarurr Granite Suites on PETERMANN RANGES.|16-MAY-23
33656|Walal Granite|Comments| Variably mylonitised and metamorphosed at ~12 kbars and 700-750oC during the c.560 Ma Petermann Orogeny.|16-MAY-23
33656|Walal Granite|References|Thomson, B.P., 1969.  The Musgrave Block.  In Parkin, L.W. (ed.) Handbook of South Australian Geology. Geological Survey of South Australia, p.39-46. **Forman, D.J. (1972). Petermann Ranges, Northern Territory.  1:250 000 geological sheet and explanatory notes.  Bureau of Mineral Resources, Canberra, Australia.|16-MAY-23
27602|Waldo Pedlar Member|Name source|The member was named after the Waldo Pedlar Bore (Wells et al 1967) (GDA94 53K 510500mE 7348500mN), approximately 22 km southeast of Ringwood Station Homestead; ILLOGWA CREEK LIMBLA, Amadeus Basin, Northern Territory.|16-MAY-23
27602|Waldo Pedlar Member|Unit history|The Waldo Pedlar Member was first defined by Wells et al (1967) as a part of the Pertatataka Formation and the unit has retained its position and name within the Pertatataka Formation after the redefinition of the Pertatataka Formation by Preiss et al (1978).|16-MAY-23
27602|Waldo Pedlar Member|Geomorphic expression|The member generally forms dark rounded hills and isolated ridges.|16-MAY-23
27602|Waldo Pedlar Member|Type section locality|The proposed type area is the hills about 12.5 km [N?] of No. 6 Phillipson Bore in northwestern HALE RIVER. Within this area a section was investigated between GDA94 53J 500318mE 7342218mN and GDA94 53J 500157mE 7342930mN in HALE RIVER.|16-MAY-23
27602|Waldo Pedlar Member|Description at type locality|Within the type area there are several locations of note; the first is at GDA94 53J 500001mE 7342474mN where the Waldo Pedlar Member consists of fine-grained, finely laminated, micaceous sandstone with soft sediment deformation. The second location is approximately 1.5 km south of Olympic Bore, at GDA94 53K 496101mE 7348254mN, where green siltstone beds with occasional beds of brown carbonate are exposed on the slope of a high ridge. The carbonate beds are approximately 2 cm wide and the green siltstone beds are strongly weathered.|16-MAY-23
27602|Waldo Pedlar Member|Extent|The Waldo Pedlar Member is restricted to the northeastern part of the Amadeus Basin between Waldo Pedlar Bore and No. 6 Phillipson Bore on HALE RIVER. Other exposures occur in the northeastern-most corner of RODINGA, with some small outcrops extending into ALICE SPRINGS southeast of Olympic Bore, and also in ILLOGWA CREEK, north of Waldo Pedlar Bore.|16-MAY-23
27602|Waldo Pedlar Member|General description|The Waldo Pedlar Member is a thin- to medium-bedded sandstone with occasional siltstone beds. Sedimentary structures include trough cross-beds; long wavelength low amplitude straight-crested, bevelled slightly sinuous-crested, asymmetric, bi-directional and interference ripple marks; flute casts; parting lineation; current lineation; and possible wind adhesion ripple marks.|16-MAY-23
27602|Waldo Pedlar Member|Thickness range|The Waldo Pedlar Member is approximately 180 m thick in the type area, where the top is not exposed.  Wells et al (1967) reported the thickness of Waldo Pedlar Member to be ca 62 m.|16-MAY-23
27602|Waldo Pedlar Member|Lithology|The Waldo Pedlar Member is a feldspathic quartz sandstone and arkose interlayered with green micromicaceous siltstone. The sandstone is fine-grained and thinly bedded with ripple and current flow markings.|16-MAY-23
27602|Waldo Pedlar Member|Depositional environment|The Waldo Pedlar Member was likely deposited during a eustatic rise triggered by the deglaciation of the Elatina ice sheet (Munson et al 2013), Walter et al (1995) suggested that the carbonate and siliciclastic rocks were deposited as a result of isostatic rebound.|16-MAY-23
27602|Waldo Pedlar Member|Fossils|None known.|16-MAY-23
27602|Waldo Pedlar Member|Relationships and boundaries|The contacts of the Waldo Pedlar Member are generally not exposed due to the recessive nature of the Pertatataka Formation siltstone that both overlies and underlies the member.|16-MAY-23
27602|Waldo Pedlar Member|Identifying features|Blocky and flaggy to fissile well-laminated, and more or less in situ, sandstone float defines weak benches that probably reflect alternating thinly and very thinly bedded sandstone respectively.|16-MAY-23
27602|Waldo Pedlar Member|Structure and Metamorphism|Due to the sporadic exposures and the restriction of the unit to the northeast of the basin, it is difficult to ascertain the extend of faulting and folding of the Waldo Pedlar Member, however any strucures are likely to be due to the 580-530 Ma Petermann and 450-300 Ma Alice Springs orogenies (Edgoose 2013 and references therein).|16-MAY-23
27602|Waldo Pedlar Member|Age reasons|The age constraint on the Pertatataka Formation is an inferred depositional age of ca 575 Ma (Edgoose 2013); however, SHRIMP U-Pb zircon analysis performed by Maidment et al (2007) yielded a maximum depositional age of ca 807 Ma for the Cyclops [Member] . Recent U-Pb isotopic studies of the detrital zircons from the Waldo Pedlar Member yielded a maximum depositional age of 678 +/- 11 Ma (Kositcin et al 2015). This is age is considerably older than the inferred depositional age of ca 575 Ma (Edgoose 2013).|16-MAY-23
27602|Waldo Pedlar Member|Correlations|There are no known direct correlatives of the Waldo Pedlar Member; this is due to the restricted distribution of the unit. The Pertatataka Formation is a correlative of the upper Inindia Beds (Edgoose 2013) in the central Amadeus Basin.|16-MAY-23
27602|Waldo Pedlar Member|Alteration and Mineralisation|Petroleum: The Waldo Pedlar Member is included in 3nd [rd?] Petroleum system of Marshall et al (2007), however, according to (Munson 2014), it is the siltstone of the Pertatataka Formation that is the potential source rock in this system, not the Waldo Pedlar Member.|16-MAY-23
27602|Waldo Pedlar Member|Geophysical Expression|Not known.|16-MAY-23
27602|Waldo Pedlar Member|Geochemistry|Not known.|16-MAY-23
27602|Waldo Pedlar Member|Defn author|VJ Normington, N Donnellan 29-SEP-2015.|16-MAY-23
27602|Waldo Pedlar Member|References|Edgoose C, 2013. Amadeus Basin: in Ahmad M and Munson TJ (editors) 'Geology and mineral resources of the Northern Territory; Special Publication 5', Northern Territory Government. **Kositcin N, Normington V and Edgoose C, 2015. Summary of results. Joint NTGS-GA geochronology project: Amadeus Basin, July 2013-June 2014. NTGS Record 2015-001, Northern Territory Geological Survey. **Maidment DW, Williams IS and Hand M, 2007. Testing long-term patterns of basin sedimentation by detrital zircon geochronology, Centralian Superbasin, Australia. Basin Research 19, 355-360. **Marshall TR, Dyson IA and Liu Keyu, 2007. Petroleum systems in the Amadeus Basin, central Australia: Were they oil prone?: in Munson TJ and Ambrose GJ (editors) 'Proceedings of the Central Australian Basins Symposium, Alice Springs, 16 - 18th August, 2005'. Alice Springs, Northern Territory Geological Survey, Special Publication 2, 136-146. **Munson TJ, 2014. Petroleum geology and potential of the onshore Northern Territory, 2014, Northern Territory Geological Survey, Report 22. **Munson TJ, Kruse PD and Ahmad M, 2013. Centralian Superbasin: in Ahmad M and Munson TJ (editors) 'Geology and mineral resources of the Northern Territory. NTGS Special Publication 5', Northern Territory Government. **Normington VJ and Donnellan N, in prep. Characterisation of the Neoproterozoic stratigraphy of the northeast Amadeus Basin, Northern Territory. Record 2015-##, Northern Territory Geological Survey. **Preiss WV, Walter MR, Coats RP and Wells AT, 1978. Lithological correlations of Adelaidean glaciogenic rocks in parts of the Amadeus, Ngalia, and Georgina basins. BMR Journal of Australian Geology and Geophysics 3, 43-53. **Walter MR, Veevers JJ, Calver CR and Grey K, 1995. Neoproterozoic stratigraphy of the Centralian Superbasin, Australia. Precambrian Research 73, 173-195. **Wells AT, Ranford LC, Stewart AJ, Cook PJ and Shaw R, 1967. Geology of the north-eastern part of the Amadeus Basin, Northern Territory BMR Report 113, Australia.|16-MAY-23
23121|Walker River Formation|Name source|From the Walker River, in the west-central part of the Blue Mud Bay-Port Langdon 1:250 000 Sheet. The headwaters of the river occur at approximately 13o20'S, 135o22'E, and the river enters the Gulf of Carpentaria at 13o35'30"S, 135o50'00"E.|16-MAY-23
23121|Walker River Formation|Unit history|This unit occupies a large part of Skwarko's (1966) 'coastal belt', and was previously placed within the Mullaman Beds. Use of the name Mullaman Beds has been discouraged (Hughes, 1978) due to the recognised stratigraphic inadequacy of the term in its original form, where it was used to describe most Mesozoic rocks in the northeastern Northern Territory. In terms of Skwarko's (1966) informal stratigraphic nomenclature, this unit is equivalent in part to Skwarko's 'units 2-7', and possibly also to 'unit B and C' of his 'inland belt'. Skwarko's (1966) informal stratigraphic nomenclature is now superseded, and usage of his informal names ('belts' and 'units') should be discontinued. Further mapping is likely to extend the known westward limit of the Walker River Formation, and an aim of such mapping should be to replace the old terminology (Mullaman Beds, and Skwarko's informal terminology) on the basis of the new stratigraphic definition proposed here.|16-MAY-23
23121|Walker River Formation|Type section locality|Reference section: Reference sections exist along the edge of dissected plateaus and large mesas in the areas surrounding the Walker River, within the boundaries of what was a large palaeoembayment in Cretaceous time between latitudes 13o21'S and 13o40'S, and longitudes 135o23'E and 135o31'E. Good reference sections also exist along the entire length of the outcrop belt of this marine shelfal formation, and the lithological character of the unit changes in response to facies changes away from the palaeoshoreline. For completeness, the locations of three reference sections are included here, covering proximal, intermediate and distal palaeogeographical settings of the unit.  In order (proximal to distal) their locations are: 13o25'51"S, 135o26'54"E on the Blue Mud Bay-Port Langdon 1:250 000 Sheet, 15o36'45"S, 135o36'30"E on the Mount Young 1:250 000 Sheet, and 17o14'00"S, 135o38'30"E on the Wallhallow 1:250 000 Sheet.|16-MAY-23
23121|Walker River Formation|Description at type locality|Lower boundary stratotype: Base of a 25.5 m interval of flat-lying sandstone, siltstone and subordinate claystone interbedded with intraformational chert granule to pebble conglomerate. This stratotype occurs as a large steep hill exposure at 17o35'30"S, 137o49'00"E on the Calvert Hills 1:250 000 Sheet. The base of the unit is represented by an erosional disconformity which is mantled locally by iron-oxide stained sandstone forming a hardground. Beneath the disconformity at the base of the Walker River Formation lies 12 m of an unnamed fining-upward sandy conglomeratic unit of probable Early Cretaceous to Jurassic age. This older unnamed Mesozoic unit overlies Proterozoic basement with angular unconformity. Upper boundary stratotype: Top of a 7 m interval of weathered, grey to white sandstone, siltstone, and claystone exposed along the banks of Wonga Creek, about 40 km southwest of Nhulunbuy, at 12o29'15"S, 136o34'00"E on the Arnhem Bay-Gove 1:250 000 Sheet. The base is not exposed, but the top is a prominent disconformity with several metres of erosional relief. Immediately overlying the disconformity are orange, large-scale trough cross-bedded sandstones of the Yirrkala Formation.|16-MAY-23
23121|Walker River Formation|Extent|The unit is extensively distributed along the western and south-western margins of the Gulf of Carpentaria, mostly within the Northern Territory but also within far northwestern Queensland. The unit is preserved as erosional remnants in the form of mesas, plateaus and low-lying rubbly hills occupying a broad zone up to 150 km inland from the present Gulf coastline. The erosional remnants commonly form outliers resting directly on Proterozoic rocks of the McArthur Basin. The area encompassed by this unit is in the order of 120 000 km2, but the western and southern margins of the outcrop belt are relatively poorly defined, as the unit tends to thin in these directions. The main outcrop belt lies east of about 134o30'E, west of 138o50'E, south of 12o05'S, and north of about 18o55'S. The outcrop belt covers a large part of the eastern Northern Territory along the margin of the Gulf of Carpentaria, and occupies all or part of sixteen 1:250 000 Sheet areas.|16-MAY-23
23121|Walker River Formation|Thickness range|Range 2 to 38 m in outcrop. At least 55 m in the subsurface (e.g. Bolton, 1982; Sands, 1979). Construction of composite sections (Krassay, 1994b) indicates that the overall thickness of the unit in outcrop is greater than 70 m.|16-MAY-23
23121|Walker River Formation|Lithology|The bulk of unit is weathered sandstone, white to dark orange, moderately to well sorted, well rounded to subangular, coarse/medium- to fine-grained quartz arenite with iron-oxide staining. Interbedded with the sandstone are flaser and lenticular interbeds of white to pale yellow, silica-cemented, finely laminated clayey siltstone. Thin, sharp-based intraformational chert and lithic pebble lags occur parallel or slightly discordant to bedding, and more rarely pebbles are concentrated into metre-wide lenses. In distal palaeogeographical localities the overall amount of sandstone is less, and the bulk of the unit consists of laminated siltstone with sandy interbeds. The unit forms both fining-upward and coarsening-upward grain size cycles, typically 5 to 10 m thick. Sedimentary structures within this heterolithic unit include hummocky cross-stratification, planar cross-bedding (most scales), wave and current ripples, gravelly ripples, ripple-lamination, convolute lamination, slump structures, gutters and gutter casts and other complex erosional scours and tool marks, graded beds, coquinas, and various styles of lamination. The unit contains abundant to rare, moderately to poorly preserved specimens of molluscan macrofossils, mainly bivalves, but also rare ammonites and belemnites. Rare stratigraphic intervals have segmented plant fossils mixed with the molluscan fossils. Marine trace fossils of the Skolithos and Cruziana ichnofacies are common, and are characteristic of the high-energy shallow-marine depositional environment of the unit (Pemberton et al., 1992). Fine-grained outcrops (and drillcore) that are not extensively weathered yield low-diversity microfloras (spores, pollen, dinoflagellates) and marine arenaceous foraminifera of the Ammobaculites Association (Haig, 1979).|16-MAY-23
23121|Walker River Formation|Relationships and boundaries|In outcrop and subsurface the unit overlies older Mesozoic units with disconformity, or Palaeoproterozoic sedimentary rocks with angular unconformity. The Walker River Formation is disconformably overlain by the Yirrkala Formation. Palaeoenvironment:  The unit generally represents high-energy deposition in the foreshore to offshore shallow-marine zone. Some interbedded stratigraphic intervals represent distal deltaic to deltaic-marine depositional environments.|16-MAY-23
23121|Walker River Formation|Age reasons|Skwarko (1966) collected marine molluscan macrofossils from these rocks and proposed an age range of Neocomian to Aptian, with rare Albian aged rocks. However, these biostratigraphic age determinations have now been refined (Krassay, 1994a, b), and the age of the unit is considered as late Aptian to early Cenomanian. Palynomorphs in the lower part of this unit, in US Steel drillholes near Numbulwar, belong to the Coptospora paradoxa spore-pollen Zone and the Canninginopsis denticulata microplankton Zone and, give an age of middle Albian (Alley, 1991). Correlative outcrops contain arenaceous foraminifera belonging to the Riyadhella crespinae Zone, which give an age range of late early Albian to late Albian for the lower to middle part of the unit (Haig, 1991). Arenaceous foraminifera belonging to the Bigenerina pitmani Zone in rocks from the lowest exposed stratigraphic interval of the unit give an age of late Aptian (Haig, 1991). On the basis of correlation to dated stratigraphic intervals on Groote Eylandt (Krassay, unpublished data), the upper part of this unit is considered to be early Cenomanian in age. The full age range of the unit is likely to be Aptian to Cenomanian.|16-MAY-23
23121|Walker River Formation|Proposed publication|Australian Journal of Earth Science: "Lithostratigraphy of the mid-Cretaceous shelf systems in Arnhem Land, NT"|16-MAY-23
23121|Walker River Formation|Category|2|16-MAY-23
23121|Walker River Formation|Proposer|Krassay A.A.|16-MAY-23
23121|Walker River Formation|Resdate|09-JAN-1995|16-MAY-23
23121|Walker River Formation|Reserved? Yes/No|Yes|16-MAY-23
78876|Wallara Formation|Name source|After Wallara No. 1 well GDA 94 53K 230787mE 7275207mN near 1.3 km northwest of Wallara in Henbury 1:250 000 sheet SG53-01, Northern Territory.|16-MAY-23
78876|Wallara Formation|Unit history|Previously known as Finke beds (Gorter 1983, Anonymous 1990).|16-MAY-23
78876|Wallara Formation|Geomorphic expression|Typically recessive where weathered but ferricrete and silcrete form upstanding ridges.|16-MAY-23
78876|Wallara Formation|Type section locality|Wallara No. 1 well GDA 94 53K 230787mE 7275207mN from 1512.12 m (base) to 1423.70 m (top).|16-MAY-23
78876|Wallara Formation|Description at type locality|Predominantly dolostone, quartz sandstone, feldspathic quartz sandstone, and red and green mudstone; with subordinate dark carbonaceous mudstone and shale and arkosic sandstone.|16-MAY-23
78876|Wallara Formation|Extent|Currently recognised in the central-northern and northeastern Amadeus Basin in Henbury SG53-01, Hermannsburg SF53-13 and Alice Springs SF53-14 1:250 000 sheets.|16-MAY-23
78876|Wallara Formation|General description|Typically deeply weathered or occuring as siliceous or ferruginous duricrust.|16-MAY-23
78876|Wallara Formation|Thickness range|88.4 m true thickness in Wallara-1 well and 35 m approximately 80 km to the northwest in Finke-1 well. Approximately 115 m of Wallara Formation are exposed at Fenn Gap between GDA 53K 360903mE 7367988mN and 53K 360903mE 7367863 mN.|16-MAY-23
78876|Wallara Formation|Depositional environment|Stromatolitic carbonate rocks suggest a shallow marine environment. Green and dark carbonaceous shales and the presence of pyrite suggest periodically anoxic conditions.|16-MAY-23
78876|Wallara Formation|Fossils|Probable Baicalia burra|16-MAY-23
78876|Wallara Formation|Relationships and boundaries|Fine to medium grained arkosic sandstone of the basal Wallara Formation overlies red dolomitic siltstone/mudstone of the Johnnys Creek Formation with a sharp, probably erosional contact. There is a coincident marked increase in gamma and resistivity in the wireline logs. The upper contact between Wallara Formation dolostone and overlying Areyonga Formation diamictite is marked by a 90 cm-thick interval of brecciated dolostone. This is interpreted to be palaeokarst.|16-MAY-23
78876|Wallara Formation|Structure and Metamorphism|The central-northern Amadeus basin succession is folded into elongate northwest-trending doubly plunging anticlines and synclines. Wallara No. 1 well was drilled off-axis with respect to a westerly-trending anticline immediately to the east (Gorter 1991). At Fenn Gap, the Wallara Formation dips consistently south at about 25°.|16-MAY-23
78876|Wallara Formation|Age reasons|Cryogenian based on the first appearance of the acritarch Cerebrosphaera buickii (Grey et al 2011).|16-MAY-23
78876|Wallara Formation|Correlations|Correlates with the Inindia beds in part.|16-MAY-23
78876|Wallara Formation|Defn author|Christine Edgoose, Verity Normington, Nigel Donnellan, 10-Nov-2014.|16-MAY-23
78876|Wallara Formation|References|Anonymous, 1990. Wallara No. 1 well completion report.Indigo Oil Pty Ltd / Sirgo Exploration Incorprated. Northern Territory Geological Survey, Open File Petroleum Report PR1990-101.***Gorter JD, 1983.Finke No. 1 well completion report. Pancontinental Petroleum Ltd, PPL Report 96. Northern Territory Geological Survey, Open File Petroleum Report PR1984-0015. ***Grey K, Hill AC and Calver CR, 2011. Biostratigraphy and stratigraphic sudivision of the Cryogenian successions of Australia in a global context, in Arnaud E, Halverson GP and Shields-Zhou (editors) 'The geologic record of Neoproterozoic glaciations.' Geological Society of London, Memoir 36, 113-134. ***Normington V, Donnellan N and Edgoose C, in prep. Stratigraphic characterisation of the Neoproterozoic sedimentary rocks of the northeast Amadeus Basin. Northern Territory Geological Survey Report.|16-MAY-23
33813|Walu Granite|Name source|Walu Outstation, western Bloods Range 1:100 000 mapsheet at location 24? 44' 25.26" S, 129? 31' 35.74" E (WGS 84).|16-MAY-23
33813|Walu Granite|Unit history|Previously described as Precambrian unnamed granites (Forman 1966)|16-MAY-23
33813|Walu Granite|Geomorphic expression|Low bouldery hills|16-MAY-23
33813|Walu Granite|Type section locality|Isolated outcrop at 24? 41' 09.48" S, 129? 26' 52.01" E (WGS 84).|16-MAY-23
33813|Walu Granite|Extent|One area of outcrop 8.5 km southwest of Mount Harris|16-MAY-23
33813|Walu Granite|Thickness range|n/a|16-MAY-23
33813|Walu Granite|Lithology|Medium grained, equigranular biotite granite|16-MAY-23
33813|Walu Granite|Depositional environment|Intrusive|16-MAY-23
33813|Walu Granite|Relationships and boundaries|Forms part of the Hull Granite Suite along with Imbumbunna Granite and Rowley Granophyre. Intrudes Mount Harris Basalt|16-MAY-23
33813|Walu Granite|Age reasons|Mesoproterozoic. U-Pb SHRIMP date of zircon yields an age of 1084 +/- 9 Ma (Close et al, 2002).|16-MAY-23
33813|Walu Granite|Correlations|Geochemically similar to the Imbumbunna Granite and the Rowley Granophyre|16-MAY-23
33813|Walu Granite|Proposed publication|Close, D.F., Edgoose, C.J., Scrimgeour, I.R., 2002. Bloods Range and Hull 1:100 000 geological special, Northern Territory Geological Survey, Explanatory notes.|16-MAY-23
33813|Walu Granite|Comments|Locally developed weak foliation from the c.570-530 Ma Petermann Orogeny|16-MAY-23
33813|Walu Granite|References|Close, D.F., Edgoose, C.J., Scrimgeour, I.R., 2002. Bloods Range and Hull 1:100 000 geological special, Northern Territory Geological Survey, Explanatory notes. **Forman, D.J., 1966. Bloods Range Northern Territory 1:250 000 geological series explanatory notes. Sheet (SG53-3). Bureau of Mineral Resources, Australia.|16-MAY-23
41856|Waluwiya Suite|Name source|Waluwiya outstation 23o 10' 00" S, 131o 27' 30" E, MOUNT LIEBIG.|16-MAY-23
41856|Waluwiya Suite|Unit history|Previously included within undifferentiated gneiss, schist, amphibolite, quartzite, granite, dolerite and pegmatite of the Arunta Complex  (Ranford 1969)|16-MAY-23
41856|Waluwiya Suite|Constituents|Larrie Granodiorite, Talyi-Talyi Charnockite, Russell Charnockite, Tjungkubu Granodiorite, Kakalyi Gneiss, unnamed equigranular granodiorite (Scrimgeour et al in prep)|16-MAY-23
41856|Waluwiya Suite|Geomorphic expression|Prominent bouldery hills and low rocky outcrops.|16-MAY-23
41856|Waluwiya Suite|Type section locality|See constituent units for respective type localities|16-MAY-23
41856|Waluwiya Suite|Extent|In hills across northern half of MOUNT LIEBIG, north of Belt Range and Mount Liebig and extending west across MOUNT RENNIE through the Ehrenberg Range to south of the Kintore Range, with a total east-west extent of over 250 km.|16-MAY-23
41856|Waluwiya Suite|Lithology|Metamorphosed pyroxene granite (charnockite) with plagioclase phenocrysts; foliated and locally migmatitic hornblende-biotite granodiorite, locally containing metamorphic garnet.|16-MAY-23
41856|Waluwiya Suite|Relationships and boundaries|The suite is most commonly fault-bounded. It intrudes metasediments of the Yaya Metamorphic Complex. The Larrie Granodiorite intrudes quartz gabbro of the Papunya Igneous Complex. In MOUNT RENNIE, the Ehrenberg and Gunbarrel Granites (Close et al in prep) locally intrude the Russell Charnockite. The Russell Charnockite is intruded by Illpilli Dolerite (Close et al in prep).|16-MAY-23
41856|Waluwiya Suite|Age reasons|late Palaeoproterozoic (1645-1630 Ma). The Talyi-Talyi Charnockite has a SHRIMP U-Pb zircon age of 1631 +/- 4 Ma (Cross et al in prep) and the Kakalyi Gneiss has a SHRIMP U-Pb zircon age of 1644 +/- 5 Ma (Kinny et al 2002)|16-MAY-23
41856|Waluwiya Suite|Correlations|No known direct correlatives, but is of a similar age to the Illili Suite and Papunya Igneous Complex (Scrimgeour et al in prep)|16-MAY-23
41856|Waluwiya Suite|Comments|Variably deformed, and metamorphosed to upper amphibolite facies.|16-MAY-23
41856|Waluwiya Suite|References|Close DF, Scrimgeour IR and Edgoose CJ, in prep. Mount Rennie, Northern Territory (Second Edition). 1:250 000 geological map series explanatory notes, SF52-15. Northern Territory Geological Survey, Darwin. **Cross A, Claoue-Long J, Scrimgeour IR, Close DF & Edgoose CJ, in prep. NTGS-GA Geochronology project, Report 6. Northern Territory Geological Survey, Record **Kinny PD, 2002. SHRIMP U-Pb geochronology of Arunta Province samples from the Mount Liebig and Lake Mackay 1:250 000 mapsheets. Northern Territory Geological Survey, Technical note 2002-015 **Ranford LC, 1969. Mount Liebig, Northern Territory (First Edition). 1:250 000 geological map series explanatory notes, SF52-16. Bureau of Mineral Resources, Australia. **Scrimgeour IR, Close DF & Edgoose CJ, in prep. Mount Liebig, Northern Territory (Second Edition) 1:250 000 geological map series explanatory notes, SE 52-16. Northern Territory Geological Survey, Darwin.|16-MAY-23
33653|Walytjatjata Granite|Name source|Walytjatjata outstation; 25o 58' 42.7"S, 129o 27' 55.9"E, PETERMANN RANGES.|16-MAY-23
33653|Walytjatjata Granite|Unit history|Comprises part of the Musgrave-Mann Metamorphics of Thomson (1969) and undivided metamorphosed granites of Forman (1972).|16-MAY-23
33653|Walytjatjata Granite|Constituents|Nil. Forms part of the Umutju Granite Suite.|16-MAY-23
33653|Walytjatjata Granite|Geomorphic expression|Rocky hills, locally high and steep, with bouldery outcrop and smooth rock faces.|16-MAY-23
33653|Walytjatjata Granite|Type section locality|In creek 3 km north of Walytjatjata outstation at 25o 56' 48.9"S, 129o 28' 24.3"E.|16-MAY-23
33653|Walytjatjata Granite|Extent|Throughout the western part of the Mann Ranges within the northern Territory, and low outcrops immediately to the north of the Mann Ranges.  Extent within South Australia and Western Australia is unknown.|16-MAY-23
33653|Walytjatjata Granite|Thickness range| n/a|16-MAY-23
33653|Walytjatjata Granite|Lithology|Variably mylonitised porphyritic clinopyroxene granite, with rounded blue-grey K-feldspar phenocrysts, typically 1-3cm but up to 6cm in diameter. Less common weakly porphyritic to equigranular phases. The primary clinopyroxene granite mineralogy is overprinted by a mylonitic fabric defined by quartz, feldspar, garnet, clinopyroxene and biotite, with or without hornblende.  Localised hydrous shear zones contain partial melts and biotite-hornblende-garnet-sphene bearing assemblages.|16-MAY-23
33653|Walytjatjata Granite|Depositional environment| n/a|16-MAY-23
33653|Walytjatjata Granite|Relationships and boundaries|Intrudes 1600-1550 granulite facies felsic and mafic gneisses.  Is intruded by 1078 Ma Alcurra Dyke Swarm and 800 Ma Amata Dyke Swarm.|16-MAY-23
33653|Walytjatjata Granite|Age reasons|Mesoproterozoic. Pb-Pb zircon evaporation age of 1175 +/- 7 Ma for porphyritic clinopyroxene granite at 25o 56' 49.6"S, 129o 24' 34.2"E.|16-MAY-23
33653|Walytjatjata Granite|Correlations|Very similar to the Mantapayika and Puka Granites (also part of the Umutju Granite Suite), with only minor textural and geochemical differences.  Similar age to Pottoyu and Mantarurr Granite Suites, PETERMANN RANGES.|16-MAY-23
33653|Walytjatjata Granite|Comments|Variably mylonitised and metamorphosed at ~12-13 kbars and 700-750oC during the c.560 Ma Petermann Orogeny.|16-MAY-23
33653|Walytjatjata Granite|References|Thomson, B.P., 1969.  The Musgrave Block.  In Parkin, L.W. (ed.) Handbook of South Australian Geology. Geological Survey of South Australia, p.39-46. **Forman, D.J., 1972. Petermann Ranges, Northern Territory.  1:250 000 geological sheet and explanatory notes.  Bureau of Mineral Resources, Canberra, Australia.|16-MAY-23
24556|Wangala Granite|Name source|Wangala Hills (metric grid reference: 200000E, 7543000N) in W part of Denison 1:100 000 Sheet area; the Hills are almost wholly composed of Wangala Granaite.|16-MAY-23
24556|Wangala Granite|Type section locality|Point 201800E, 7544800, 5 km SSE of Mount Denison H.S., in W part of Denison 1:100 000 Sheet area. Dynamited for isotopic dating, shows coarse porphyritic granite with aligned tabular phenocrysts of K-spar intruded by medium-grained porphyritic granite. Another reference locality is at point 194100E, 7537700N, in W. part of Denison 1:100 000 Sheet area, 13 km SSW of Mount Denison H.S. Shows good exposure of rapakivi granite in contact with and intruded by medium-grained porphyritic granite; rapakivi forms at least one large xenolith in medium-grained porphyritic granite, with chilled porphyritic granite shell around xenolith. Large pegmatite dyke along contact of 2 granites, zoned, with core of aplite containing K-spar phenocrysts up to 28 cm across.|16-MAY-23
24556|Wangala Granite|Extent|Wangala Hills in W part of Denison 1:100 000 Sheet area: small outcrops to east into SW corner of Reynolds Range 1:100 000 Sheet area.|16-MAY-23
24556|Wangala Granite|Lithology|Mostly medium-grained massive to foliated even-grained granite in E, and coarse porphyritic granite with aligned euhedral tabular phenocrysts of K-feldspar and some coarse rapakivi granite in W. These earlier granites are intruded by subsidiary smaller bodies of medium-grained porphyritic granite and by microgranite.|16-MAY-23
24556|Wangala Granite|Relationships and boundaries|Intrudes calc-silicate rock, quartzite, porphyry, and amphibolite at Mount Allan Tin Mine: these metasediments are correlated with Wickstead Creek beds of adjoining Reynolds Range 1:100 000 Sheet area to E. Intrudes Ngalurbindi Orthogneiss (q.v.). Is intruded by pegmatite, dolerite and/or amphibolite, and by porphyry dykes.|16-MAY-23
24556|Wangala Granite|Identifying features|Reason for proposed name: A distinctive composite body of several types of granite, easily distinguished from surrounding rocks.|16-MAY-23
24556|Wangala Granite|Age reasons|Nolt dated isotopically. Probably ;only ;slightly younger than Ngalurbindi Orthogneiss, and hence late Early Proterozoic or early Middle Proterozoic.|16-MAY-23
24556|Wangala Granite|Proposed publication|1. 'Geology of NW Arunta Block, NT' - BMR Publication.  2. 'Stratigraphic definitiison in Arunta Block' - BMR Microfiche Report.|16-MAY-23
24556|Wangala Granite|Defn Reference|80/20787|16-MAY-23
24556|Wangala Granite|Proposer|Stewart A.J.|16-MAY-23
24556|Wangala Granite|Reserved? Yes/No|Yes|16-MAY-23
38512|Wangalinji Member|Name source|From Wangalinji Outstation, an Aboriginal settlement in the Waanyigarawa (Nicolson River) Land Trust, at latitude 18o23'41" longitude 137o28'04", in MOUNT DRUMMOND.|16-MAY-23
38512|Wangalinji Member|Unit history|Previously mapped as Constance Sandstone on the first edition MOUNT DRUMMOND by Smith and Roberts (1963), and on the Carrara Range region 1:100 000 sheet by Sweet (1984). Some outcrops included in the Lawn Hill Formation by Sweet (1984).|16-MAY-23
38512|Wangalinji Member|Geomorphic expression|A low ridge or rubble-strewn rise corresponding to the basal sandstone and an adjacent valley or undulating terrain corresponding to the upper, finer-grained part.|16-MAY-23
38512|Wangalinji Member|Type section locality|4 km southeast of Mitchiebo Waterhole, in MOUNT DRUMMOND. The section runs from south to north: base is at latitude 18o39'57"S longitude 137o7'38"E (724360E 7934820N), the top about 300 m to the north, at 724130E 7935360N.|16-MAY-23
38512|Wangalinji Member|Extent|Forms a west to west-southwest-trending outcrop belt in central to southwestern MOUNT DRUMMOND, from the headwaters of Maloney Creek in the east, to Waterfall Creek in the southwest. An isolated outcrop occurs in the northwest, east of the headwaters of Benmara Creek.|16-MAY-23
38512|Wangalinji Member|Thickness range|390 m in the type section, and 750 m in the Playford Anticline 11 km to the northwest.|16-MAY-23
38512|Wangalinji Member|Lithology|Basal white, thick-bedded, medium- to coarse-grained cross-bedded sandstone, with current ripples and primary current lineation, scattered mudstone intraclasts, and granule and pebbly layers; clasts mainly of quartz. Remainder of unit is laminated shale with thin-bedded siltstone and very fine-grained lithic sandstone interbeds, interbedded with medium to thick beds of white cross-bedded, sub-lithic, medium- to coarse-grained sandstone; minor purple-red mudstone with discontinuous disrupted laminae, ubiquitous mudflakes, and desiccation cracks, and rare stromatolitic chert and carbonates.|07-OCT-23
38512|Wangalinji Member|Relationships and boundaries|Overlies Widdallion Sandstone Member of the Lawn Hill Formation disconformably in outcrops between Mitchiebo Waterhole and Western Creek, a distance of about 50 km. Southwest of Mitchiebo Waterhole an angular unconformity exists between the two. The boundary is marked by an abrupt change from purple/brown highly micaceous and lithic sandstones of the Widdallion Sandstone Member, to lighter coloured (white, light brown or pink) more quartz-rich granule to pebbly sandstone of the Wangalinji Member. The upper boundary, with the Top Lily Sandstone Member, is conformable. It is marked by a rapid transition from interbedded siltstone and shale to thick bedded pink to brown, fine-grained lithic sandstone of the Top Lily Sandstone Member. Parent unit: Playford Sandstone.|16-MAY-23
38512|Wangalinji Member|Age reasons|A maximum age of 1591+/-10 Ma, based on reworked tuffaceous material from the underlying Lawn Hill Formation (Page et al 2000) in LAWN HILL, or 1595+/-6 Ma based on tuffs in the Lawn Hill Formation in the same area (Page and Sweet 1998). The interpreted age range of 1500-1400 Ma for the South Nicholson Group is based on its correlation with the Roper Group of the southern McArthur Basin (Dunn et al 1966; Plumb & Derrick 1975). Ages of 1492+/-4 and 1493+/-4 Ma for tuffaceous material from the Mainoru Formation in the Roper Group (Jackson et al 1999) provides the most reliable estimate for the age of the lower part of that Group, and hence for the Playford Sandstone and its members.|16-MAY-23
38512|Wangalinji Member|Correlations|None known, but it is likely that sandstones low in the Renner Group (Hussey et al 2001) and the Roper Group (Jackson et al 1999) are in part correlative, given the overall correlation between these groups.|16-MAY-23
38512|Wangalinji Member|Defn author|Rawlings, D.J. [approved 11-APR-2005]|16-MAY-23
38512|Wangalinji Member|Comments|The concordant nature of the contact led Sweet (1984) to include the member in the underlying Widdallion Sandstone Member in eastern outcrops, adjacent to Western Creek. Note: All locations are based on the GDA94 geodetic datum. Standard series 1:250 000 sheet names are shown in upper case.|16-MAY-23
38512|Wangalinji Member|References|**DUNN P.R., Plumb K.A. and Roberts H.G. 1966. A proposal for time-stratigraphic subdivision of the Australian Precambrian. Journal of the Geological Society of Australia, 13, 593-608.  **HUSSEY K.J., Beier P.R., Crispe A.J., Donnellan N. and Kruse P.D. 2001. Helen Springs, Northern Territory (Second Edition); 1:250 000 geological series, sheet SE53-10.   **JACKSON M.J., Sweet I.P., Page R.W. and Bradshaw B.E., 1999. The South Nicholson and Roper Groups: evidence for the early Proterozoic Roper Superbasin. In: Bradshaw B.E. and Scott D.L. (Eds.), Integrated basin analysis of the Isa Superbasin using seismic, well-log and geopotential data: an evaluation of the economic potential of the northern Lawn Hill Platform. Australian Geological Survey Organisation, Record 1999/19 (unpaginated).    **PAGE R.W., Jackson M.J. and Krassay A.A., 2000. Constraining sequence stratigraphy in north Australian basins: SHRIMP U-Pb zircon geochronology between Mt Isa and McArthur River. Australian Journal of Earth Sciences, 47, 3; 431-459.  **PAGE R.W. and Sweet I.P., 1998. Geochronology of basin phases in the western Mount Isa Inlier, and correlation with the McArthur Basin. Australian Journal of Earth Sciences, 45, 2; 219-232.  **PLUMB K.A. and Derrick G.M., 1975. Geology of the Proterozoic rocks of the Kimberley to Mount Isa Region. In Knight C.L. (Editor), Economic Geology of Australia and Papua New Guinea, 1. Metals. The Australasian Institute of Mining and Metallurgy, Monograph Series, 5, 217-252.  **SMITH J.W. and Roberts H.G., 1963. Mount Drummond, N.T. (First Edition); 1:250,000 geological series, sheet SE53-12. Bureau of Mineral Resources, Geology and Geophysics, Map and Explanatory Notes.  **SWEET I.P., 1984. Carrara Range region, Northern Territory (First Edition); 1:100,000 geological series, portions of sheets 6460 and 6360. Bureau of Mineral Resources, Geology and Geophysics, Explanatory Notes.|16-MAY-23
26331|Warimbi Schist|Name source|Warimbi Hills (5453-880240), in southeastern part of Reynolds Range 1:100 000 sheet area.|16-MAY-23
26331|Warimbi Schist|Unit history|Mapped as 'Granodiorite' by Australian Geophysical (1967), described as 'porphyry' by Evans & Glikson (1969), mapped as 'Precambrian quartz-feldspar porphyry' and 'Precambrian igneous and metamoprhic rocks' by Wells & others (1971).|16-MAY-23
26331|Warimbi Schist|Type section locality|5453-772315, 3 km east of Mount Thomas, interpolated in type section of Mount Thomas Quartzite (q.v.)|16-MAY-23
26331|Warimbi Schist|Extent|Central part of Reynolds Range, from neighbourhood of Mount Thomas to 16 km southeast of Mount Thomas.|16-MAY-23
26331|Warimbi Schist|Thickness range|350 m at type locality; three smaller sills injectedat successively higher stratigraphic levels in Reynolds Range Group are 6 m, 6 m, and 50 m thick, respectively.|16-MAY-23
26331|Warimbi Schist|Lithology|A sill (lopolith) of medium to fine-grained orthoschist comprising broken porphyroclasts of quartz with deep magmatic resorption embayments, and elongate aggregates of biotite flakes, in schistose fine groundmass of recrystallised quartz and oriented muscovite and biotite.|16-MAY-23
26331|Warimbi Schist|Relationships and boundaries|Intrudes Mount Thomas Quartzite and Pine Hill Formation; contains numerous xenoliths and rafts of Mount Thomas Quartzite.|16-MAY-23
26331|Warimbi Schist|Age reasons|Muscovite has given single K-Ar date of 1370 m.y. (Lowder & Webb, 1972) but probably partly reset by Alice Springs Orogeny. Younger than depositional age of Mount Thomas Quartzite and Pine Hill Formation, but older than metamorphic age (1500 m.y.) of these units. Hence, Middle Proterozoic or older.|16-MAY-23
26331|Warimbi Schist|Proposed publication|Stratigraphic definitions in Arunta Block' - BMR Microfiche Report|16-MAY-23
26331|Warimbi Schist|Defn Reference|80/20787|16-MAY-23
26331|Warimbi Schist|Proposer|Stewart A.J.|16-MAY-23
26331|Warimbi Schist|Reserved? Yes/No|Yes|16-MAY-23
24562|Warnes Sandstone Member|Name source|Warnes Gully, which trends east-west between the northerly draining Mia Mia and Hatches Creeks, near GR 180870, Hatches 1:100 000 Sheet area, Frew River 1:250 000 Sheet area.|16-MAY-23
24562|Warnes Sandstone Member|Type section locality|3.5 km south-southeast of the Pioneer mine (latitude 20o52'10"S, longitude 135o11'00"E), Hatches Creek, from GR 192886 to GR 192878, Hatches 1:100 000 Sheet area, where the member forms two prominent strike ridges. Neither stratigraphic base nor top seen here but contacts with underlying and overlying undivided Kurinelli Sandstone are exposed at GR 202910 and GR 178877, respectively, Hatches 1:100 000 Sheet area.|16-MAY-23
24562|Warnes Sandstone Member|Extent|Southern central Hatches 1:100 000 Sheet area, and also in southeastern Davenport Range 1:100 000 Sheet area (Bonny Well 1:250 000 Sheet area).|16-MAY-23
24562|Warnes Sandstone Member|Thickness range|0 to about 500 m.|16-MAY-23
24562|Warnes Sandstone Member|Lithology|Poorly sorted, apparently non-bedded, quartzose arenite, commonly containing scattered grit grains and small pebbles of vein quartz; minor lenses of bedded quartz arenite.|16-MAY-23
24562|Warnes Sandstone Member|Relationships and boundaries|Forms conformable discontinuous band or lenses within the Kurinelli Sandstone; intruded by sill-like bodies of granophyre and dolerite/gabbro.|16-MAY-23
24562|Warnes Sandstone Member|Age reasons|Younger than 1870 m.y. - U-Pb zircon age for volcanic of the Warramunga Group unconformably overlain by the Hatches Creek Group. Older than 1640 m.y. - Rb-Sr whole-rock approximate age for granite intruding the Hatches Creek Group.|16-MAY-23
24562|Warnes Sandstone Member|Defn author|Blake D.H., Stewart A.J., Sweet I.P., Wyche S., 1985.|16-MAY-23
24562|Warnes Sandstone Member|Comments|Remarks: Forms distinctive knobbly, rather than smooth, strike ridges. Kurinelli Sandstone, which includes the Warnes Sandstone Member, is part of the Ooradidgee Subgroup of the Hatches Creek Group.|16-MAY-23
24562|Warnes Sandstone Member|Defn Reference|86/25362|16-MAY-23
24562|Warnes Sandstone Member|Proposer|Blake D.H.|16-MAY-23
24562|Warnes Sandstone Member|Resdate|07-OCT-1981|16-MAY-23
24563|Warramana Sandstone|Name source|Warramana Creek, Mount Young 1:250 000 scale map sheet area.|16-MAY-23
24563|Warramana Sandstone|Unit history|The Warramana Sandstone was mapped without adequate definition on the first edition Mount Young (Plumb and Paine, 1964) and Bauhinia Downs (Smith, 1964) 1:250 000 geological map and was at that time considered to belong to the McArthur Group. Plumb and Brown (1973) recommended abandonment of the name as they considered it synonymous with the Tatoola Sandstone of the McArthur Group. Muir (1980) reinterpreted many outcrops as the Cambrian Bukalara Sandstone. However, remapping by Haines and others (in press) indicates that most outcrops originally mapped as Warramana Sandstone represent a distinct formation situated stratigraphically near the top of the Tawallah Group. Outcrops of sandstone in the Pellew 1:250 000 sheet area, previously mapped as 'Masterton Formation' by Smith (1963), are now identified as Warramana Sandstone.|16-MAY-23
24563|Warramana Sandstone|Geomorphic expression|Outcrops well as low hills or strike ridges, often with a distinctive 'pseudokarstic' weathering pattern.|16-MAY-23
24563|Warramana Sandstone|Type section locality|At latitude 15o43.6'S, longitude 135o42.3'E (AMG grid reference NC625060) in southern Scrutton Range in the Bauhinia Downs 1:250 000 map sheet area. This is the only section with conformable lower and upper contacts. This section is presented graphically in Pietsch and others (1991).  Reference sections: Refereance sections are nominatead at NC890640 and the core from diamond drillhole McA14 (PC331570; stored at Department of Mines and Energy Core Library, Darwin; log in Haines and others, in press) on the Mount Young 1:250 000 map sheet area, as the type section does not display the full range of lithologicall units seen throughout the formation's distribution.|16-MAY-23
24563|Warramana Sandstone|Extent|Mainly restricted to the eastern half of the Mount Young and southwestern corner of the Pellew 1:250 000 map sheet areas. Localised outcrops have been identified in western Mount Young and northern Bauhinia Downs 1:250 000 map sheet areas.|16-MAY-23
24563|Warramana Sandstone|Thickness range|115 m at the type section. The greatest recorded thickness is an incomplete intersection of 255 m in diamond drillhole McA14. Reference locality at NC890640 is estimated to be 240 m thick.|16-MAY-23
24563|Warramana Sandstone|Lithology|The formation can be lithologically subdivided into 4 subunits although some are of local extent only. Unit 1 (base) is most widespread in outcrop, while unit 4 (top) is restricted to one outcrop only (NC890640), and here separated from unit 3 by a non-outcropping interval. Unit 1: red-brown to pink, mainly medium-grained thin- to medium-bedded litharenite. Unit 2: thin horizon of ferruginous sandstone and mudstone. Includes an interval of pisolitic ironstone and conglomerate in McA14. Unit 3: pale pink to white, fine- to coarse-grained sublitharenite and quartzarenite, becoming less lithic up-section. Unit 4: similar to unit 1 although with a somewhat greater lithic content. Lithic material is dominated by felsic volcanic fragments throughout the formation. All units are flat-bedded to trough cross-bedded and display wave and current ripples.|16-MAY-23
24563|Warramana Sandstone|Depositional environment|Mainly shallow marine high-energy environment associatead with penecontemporaneous volcanic activity.|16-MAY-23
24563|Warramana Sandstone|Relationships and boundaries|Assigned to the Tawallah Group, McArthur Basin. Conformably overlies the Wollogorang Formation or, where locally present, the Gold Creek Volcanics. Contact picked at the incoming of red, medium-grained, lithic sandstone above finer siliciclastic and carbonate rocks or volcanics of the underlying units. Conformably overlain by Tanumbirini Rhyolite or disconformably by Nyanantu Formation. The Masterton Sandstone overlies with an unconformable relationship at one section.|16-MAY-23
24563|Warramana Sandstone|Age reasons|Statherian based on 1713 +/- 6 Ma age of conformably overlying Tanumbirini Rhyolite (Haines and others, in press).|16-MAY-23
24563|Warramana Sandstone|Proposed publication|Mount Young 1:250 000 Geological lMap Series, Explanatory Notes (Haines and others, in press).|16-MAY-23
24563|Warramana Sandstone|Category|Definition of existing unit|16-MAY-23
24563|Warramana Sandstone|Name first published by|Smith, 1963. Pellew, NT 1:250 000 Explan. Notes|16-MAY-23
24563|Warramana Sandstone|Proposer|Haines P.W., Pietsch B.A., Rawlings D.J., Madigan T. 1993 (after Plumb and Paine, 1964; Smith, 1964).|16-MAY-23
30741|Warramunga Formation|Unit history|The name Warramunga Group was introduced by Ivanac (1954) to replace the Warramunga Series of Owen (1940). The Wanamunga Group was described in detail by Dunnet  and Harding  (1967) and defined by Mendum et al. (1978). Recent mapping has shown that many of the formal and informal units previously included in the Warramunga Group are lithologically and structurally distinct from the polydeformed lithic arenite, wacke, siltstone  and shale which constitute a homogeneous unit, the Warramunga Formation of present usage. In large part equivalent to informal units (Mendum et al. 1978) Ew2 and Ew6 of the former Warramunga  Group,  together  with  part  of  units  Ew7 and  Ew3.|16-MAY-23
30741|Warramunga Formation|Geomorphic expression|Upstanding ridges of deeply dissected Ashburton Surface of planation and surrounding colluvium strewn plain of former, Tertiary, Tennant Creek Surface of planation.|16-MAY-23
30741|Warramunga Formation|Type section locality|Sandstone lithofacies at lat. 19deg03'53", long. 134deg13'47"E    (GR MU192306),  where    medium-, thick- or massively-bedded coarse-, very coarse- and granule-bearing lithic arenite is interbedded with minor thin- to medium-bedded, fine-grained sandstone and siltstone.   Reference locality: Siltstone lithofacies at lat. 19deg03'20"S, long. 134deg09'30"E (GR MU117301), where tabular and well cleaved fine-grained lithic arenite and siltstone are interbedded. Reference sections: Principal reference sections for sandstone and  siltstone lithofacies are from lat. 19deg37'23"S, long. 134deg12'46"E (GR MU173300) for 97.8 m updip to southsoutheast, and from lat. 19deg37'26"S, long. 134deg09'28"E (GR MU11730l) for 75.5 m updip to south respectively. Additional reference section for sandstone lithofacies is from lat. 19deg36'04"S, long. 134deg17'23"E (GR MU255325) for 48.3 m updip to southsoutheast. Further reference sections for siltstone lithofacies are from lat. 19deg39'52"S, long. 134deg08'49"E (GR MU105365; near Grays Bluff) for 220 m updip to southsoutheast, and  from  lat.  19deg36'17"S,  long.   134deg18'21"E (GR MU272321) for 146.5 m updip to southsouth­ east.|16-MAY-23
30741|Warramunga Formation|Extent|Crops out in central TENNANT CREEK, particularly in TENNANT CREEK, FLYNN and SHORT RANGE, and in the Davenport province on northern BONNEY WELL and FREW RIVER.|16-MAY-23
30741|Warramunga Formation|Thickness range|Lack of continuity of outcrop and polydeformation preclude precise determination of thickness. Estimated thickness about 3000 m.|16-MAY-23
30741|Warramunga Formation|Lithology|Lithic arenite, and volcanic  litharenite  and wacke; siltstone; mudstone/shale, phyllite and slate; chert and jaspilite; banded ironstone known  locally as 'haematite shale'; and minor probable tuff. Unit is divided into a Sandstone (sst> slst) and a Siltstone (slst >sst) lithofacies based on the  relative  proportion of coarse-grained/sandstone to fine-grained/silt­ stone beds. Greywacke and ignimbritic quartz­ feldspar porphyry have been described in BONNEY WELL (Wyche and Simons 1987).|16-MAY-23
30741|Warramunga Formation|Depositional environment|Classic  proximal  to   distal flysch succession.|16-MAY-23
30741|Warramunga Formation|Relationships and boundaries|Top boundary stratotype: An  angular  unconformity between Warramunga Formation and Hatches Creek Group in the Gilbert Anticline on BONNEY WELL (GR MT355657 (Wyche and Simons  1987)).Bottom boundary stratotype: The underlying  unit  is nowhere exposed on TENNANT CREEK or surrounding sheet areas. Unconformably overlain by Hatches Creek Group on BONNEY WELL. There is a marked change in  lithology between the Warramunga Formation and overlying Flynn Subgroup of the Churchills Head Group on TENNANT CREEK. The Flynn Subgroup has  one less deformation than the Warramunga Formation, from which an unconformable relationship can be inferred. Underlying unit nowhere exposed but inferred to be equivalents of higher metamorphic grade, more iron-rich metasediments or older sialic basement. Unconformably overlain by Gum Ridge Formation and Helen Springs Volcanics. Intruded by acid porphyry, granite  (Tennant Creek Granite, Hill of Leaders Granite, Mumbilla Granodiorite,  'Warrego Granite') and lamprophyres, and crosscut by numerous quartz veins.  Apparently  locally  replaced by  massive  magnetite,   which  together  with  chloritised Warramunga Formation sedimentary rocks is host to economic Cu-Au-Bi mineralisation. Frequent faulted contacts with younger units.|16-MAY-23
30741|Warramunga Formation|Structure and Metamorphism|Polydeformed, cleaved, faulted and sheared. Lateritisation tends to result in an over-represention of steep dips relative to shallow dips, with bedding being particularly difficult to determine  in fold closures where it makes a high angle to cleavage.|16-MAY-23
30741|Warramunga Formation|Age reasons|Palaeoproterozoic. U-Pb ion microprobe ages of 1884+/-13 Ma and  1862+/-10 Ma for detrital zircons from Warramunga Formation sediments are given by Compston (1991), and subsequently revised to 1862+/-9 Ma and 1859+/-13 Ma by Compston (1994), who interprets them as the maximum age of sedimentation of  the  'Warramunga Group' (Warramunga Formation as defined here).|16-MAY-23
30741|Warramunga Formation|Correlations|May correlate with the Bullion Schist; and in turn with the Lander Rock beds (Stewart et al. 1980).|16-MAY-23
30741|Warramunga Formation|Defn author|Redefinition after Waramunga Group. Donnellan, N. 1995.|16-MAY-23
30741|Warramunga Formation|Comments|First definition of this name. Redefinition after Waramunga Group.|16-MAY-23
19520|Warrego Volcanics|Name source|Warrego Mine, in Tennant Creek 1:250 000 Sheet area, Grid reference 376849.|16-MAY-23
19520|Warrego Volcanics|Type section locality|No type section was measured for the unit; exposure is poor and the lithology shows marked lateral variation. the outcrop on the northern limb of the Great Western Syncline, where the whole sequence is present, is regarded as the type area. The basal beds are exposed on the southern margin of that topped hills in a crescent shaped outcrop area south of Black Angel Trig., in two areas within the Great Western Syncline, one along its southern margin 8 to 14km east northeast of Warrego mine and the other 5km northwest of the Great Western Trig., and in the sides of the Warrego No 2. Dam. They consist of volcanic rocks- pyroclastics (one or more of ashstone, agglomerate and tuffaceous siltstone), and in addition dark purple to cream and pink rhyolitic lava on the southern limb of the syncline - interbedded with sedimentary rocks - fine to coarse-grained greywacke, and in addition grey, finely banded hematite shale along the southern limb, where it forms the basal bed and purple cleaved shale, pink claystone and chert 5km north west of Great Western Trig. Beds higher in the sequence are exposed in the western part of the Great Western Syncline; 6km and 8.5 km southeast of the Warrego Mine; 1 km south and 700m-southeast of Black Angel Trig., of the copper smelter 11km east of the Warrego Mine, and at localities 0.5km southwest and 3.5km northeast of the smelter. They include volcanic rocks - minor aggl0omerate, tuff (In part feldspathic, shaly, silcified, flaggy to block, finely banded, fissile, cleaved, fine to coarse-grained; white, red-grey, grey-purple, pink. fawn), greywacke (in part feldspathic; fine-grained), siltstone, cherty siltstone, shale, hematite shale, chert (in part finely banded; flaggy), chert breccia. Beds near the top of the sequence in the western part of the Great Western Syncline consist of flaggy to blocky tuff and leached white tuffaceous siltstone interbedded with pink and cream cherty ashstone. The topmost beds, along the northern limb of the syncline, consist of cream, pink and purple ashstone overlain by blocky tuff and greywacke.|16-MAY-23
19520|Warrego Volcanics|Extent|Crops out in an area of 21 km ^2 between the Orlando and Warrego Mines. The largest single area of outcrop is 11km east-northeast of Warrego Mine where the volcanics define the westerly plunging Great Western Syncline. Numerous faults complicate the areal distribution of the unit. The volcanics are exposed in a fault block 8.5km southeaste of the Warrego Mine. Further west, the upper part of the volcanics is exposed in an anticline.|16-MAY-23
19520|Warrego Volcanics|Thickness range|Ranges from 550 m in the type area to about 200m at a locality 7km southeast of the Warrego Mine.|16-MAY-23
19520|Warrego Volcanics|Lithology|Purple banded rhyolite, grey ignimbrite, pink ashstone and tuff and grey banded hematite shale, interbedded with siltstone, greywacke, shale and minor chert.|16-MAY-23
19520|Warrego Volcanics|Relationships and boundaries|Conformably overlies the informally named unit Lw7, and is conformably overlain by the informally named unit LW3. The lower contact is sharply defined around the southern limb of the Great Western Syncline where the basal bed of the volcanics-banded hematite shale- overlies claystone and tuffaceous siltstone of unit Lw7. In the sides of Warrego No. 2 Dam pink, blocky to flaggy, compact, finely-banded silicified ashstone overlies purple to white flaggy siltstone of unit Lw7. The upper contact grades into unit Lw3 and is marked by the highest tuff, ashstone or lava in the sequence: it is exposed around the northern limb of the Great Western Syncline and at a locality 0.5km southwest of the black Angel Mine.|16-MAY-23
19520|Warrego Volcanics|Age reasons|According to Black (1977), The Warramunga Group of which the Warrego Volcanics is a constituent formation, is early Proterozoic in age. It was intruded by granite as old as 1797 Ma; the major deformation of the group took place 1810 Ma ago.|16-MAY-23
19520|Warrego Volcanics|Defn author|? Mendum, J.R., Tonkin, P.C. ?1978.|16-MAY-23
19520|Warrego Volcanics|References|Black, L.P., 1977 - A Rb-Sr geochronological study in the Proterozoic Tennant Creek Block, central Australia. BMR Jour. Australian Geol. and Geophys. 2(2), pp.111-122. **Dodson, A.G. and Gardener, J.E.F. (in prep) - Tennant Creek, N.T. 1:250 000 Geological Series. BMR. Australia explan. Notes SE/53-14. **Mendum, J.R. and Tonkin, P.C. (submitted by D.E. Gardner) in prepr. - proposed stratigraphic names, Tennant Creek 1:250 000 Sheet area, Northern Territory. BMR Jour. Australian Geol. and Geophys.|16-MAY-23
24631|Warrs Volcanic Member|Name source|Warr's Prospect, Daly River 1:100 000 map AMG 859933.|16-MAY-23
24631|Warrs Volcanic Member|Unit history|A not previously recognised volcanic unit within the metasediments of the Burrell Creek Formation.|16-MAY-23
24631|Warrs Volcanic Member|Type section locality|AMG 861947 (latitude 13o36'37"S, longitude 130o43'13"E). Crops out as foliated, usually weathered, bands interbedded with phyllite.|16-MAY-23
24631|Warrs Volcanic Member|Extent|Crops out in a zone of about 15 km2 running NNE from the Daly River Copper Mine to Kilfoyle Creek.|16-MAY-23
24631|Warrs Volcanic Member|Thickness range|About 500 m.|16-MAY-23
24631|Warrs Volcanic Member|Lithology|Biotite-chlorite metadacite.|16-MAY-23
24631|Warrs Volcanic Member|Relationships and boundaries|Interbedded and interfingers with phyllite near the base of the Burrell Creek Formation. Probably genetically related to massive sulphide (mainly sphalerite) mineralisation.|16-MAY-23
24631|Warrs Volcanic Member|Age reasons|Early Proterozoic.|16-MAY-23
24631|Warrs Volcanic Member|Proposed publication|Dundas D.L., Edgoose C.J., Fahey G.M., Fahey J.E., in prep. - Explanatory Notes (for) Daly River (5070). Northern Territory Geological Survey 1:100 000 Geological Map Series. Northern Territory Government Printer, Darwin.|16-MAY-23
24631|Warrs Volcanic Member|Proposer|Dundas D.L., Edgoose C.J. (submitted by D L Dundas)|16-MAY-23
41857|Warumpi Granite|Name source|Warumpi outstation, 3 km east of Papunya 23o 13' 00" S, 131o 46' 45" E, MOUNT LIEBIG.|16-MAY-23
41857|Warumpi Granite|Unit history|Previously included within undifferentiated gneiss, schist, amphibolite, quartzite, granite, dolerite and pegmatite of the Arunta Complex  (Ranford 1969)|16-MAY-23
41857|Warumpi Granite|Geomorphic expression|Prominent hills|16-MAY-23
41857|Warumpi Granite|Type section locality|Southwestern side of hill 3 km east of Papunya (23o12?46.88?S 131o56?35.34?E, WGS 84), MOUNT LIEBIG.|16-MAY-23
41857|Warumpi Granite|Description at type locality|Highly strained and locally migmatitic gneissic rapakivi biotite granite with rounded phenocrysts of K-feldspar up to 2-3cm in diameter. The rock contains an early high-grade gneissic S1 fabric, overprinted by a variably developed higher strain mylonitic fabric at high angles to S1. Biotite is the dominant mafic mineral, with common hornblende and opaques and minor titanite.|16-MAY-23
41857|Warumpi Granite|Extent|In a region of prominent hills 10-15 km west of Papunya community, and a prominent hill 3 km east-southeast of Papunya community, MOUNT LIEBIG. May extend into northwestern HERMANNSBURG.|16-MAY-23
41857|Warumpi Granite|Lithology|Foliated to gneissic biotite granite, with large rounded phenocrysts of K-feldspar that are locally flattened and elongated in the fabric and locally preserve rapakivi textures. The granite has locally undergone partial melting. The mineralogy of the granite comprises quartz, K-feldspar, plagioclase, biotite, titanite and oxides, with local occurrences of hornblende.|16-MAY-23
41857|Warumpi Granite|Relationships and boundaries|The Warumpi Granite intrudes interlayered mafic and pelitic granulite of the Yaya Metamorphic Complex, and has intrusive contacts (with no clear timing relationships) with the Larrie Granodiorite.  It is interpreted to be intruded by an unnamed body of granular gabbro. The unit is commonly fault-bounded.|16-MAY-23
41857|Warumpi Granite|Age reasons|late Palaeoproterozoic. A sample of gneissic Warumpi Granite from the type locality  has a SHRIMP U-Pb zircon age of 1642 +/- 3 Ma. A foliated biotite granite from just north of the Kintore road at 23o11?34.19?S 131o43?59.88?S has a SHRIMP U-Pb zircon age of 1639 +/- 3 Ma (Cross et al in prep).|16-MAY-23
41857|Warumpi Granite|Correlations|Strong geochemical affinity with other granites of the Illili Suite, including Ehrenberg Granite and Gunbarrel Granite, MOUNT RENNIE (Close et al in prep).|16-MAY-23
41857|Warumpi Granite|Comments|Metamorphosed at granulite to upper amphibolite facies during 1640-1635 Ma Liebig Orogeny and 1590-1570 Ma Chewings Orogeny.|16-MAY-23
41857|Warumpi Granite|References|Close DF, Scrimgeour IR and Edgoose CJ, in prep. Mount Rennie, Northern Territory (Second Edition). 1:250 000 geological map series explanatory notes, SF52-15. Northern Territory Geological Survey, Darwin. **Cross A, Claoue-Long J, Scrimgeour IR, Close DF & Edgoose CJ, in prep. NTGS-GA Geochronology project, Report 6. Northern Territory Geological Survey, Record.  **Ranford LC, 1969. Mount Liebig, Northern Territory (First Edition). 1:250 000 geological map series explanatory notes, SF52-16. Bureau of Mineral Resources, Australia. **Scrimgeour IR, Close DF & Edgoose CJ, in prep. Mount Liebig, Northern Territory (Second Edition) 1:250 000 geological map series explanatory notes, SE 52-16. Northern Territory Geological Survey, Darwin.|16-MAY-23
84111|Waterfall Member|Name source|Unit name derived from Waterfall Creek, which rises at approximately (GDA94) 18°40’57”S 136°39’12”E in the MOUNT DRUMMOND 1:250 000 mapsheet, Northern Territory.|
84111|Waterfall Member|Unit history|Unit was originally mapped as an undivided part of the “Constance Sandstone” on the First Edition MOUNT DRUMMOND 1:250 000 mapsheet (Smith and Roberts, 1963a, b) and subsequently remapped as part of the “Wangalinji Member” of the “Playford Sandstone” on the Second Edition MOUNT DRUMMOND 1:250 000 mapsheet by Rawlings et al (2008). Some outcrops were included in the “Lawn Hill Formation” by Sweet (1984). The rocks of the “Playford Sandstone” and the Wangalinji Member north of the Mitchiebo-Maloney fault have been shown to be older than the rocks of those units south of the fault hence the creation of  which contains the “Waterfall Member” of has itself been renamed to the “Fish Hole Sandstone” for the older rocks.|
84111|Waterfall Member|Geomorphic expression|Low ridge or rubble-strewn rise corresponding to basal sandstone and an adjacent valley or undulating terrain corresponding to upper, finer-grained part (Rawlings et al, 2008).|
84111|Waterfall Member|Type section locality|There is no type locality nominated for this member. A reference area is here nominated in the western MOUNT DRUMMOND 1:250 000 mapsheet, in the vicinity of (GDA94) 18°38’S 136°47’E.|
84111|Waterfall Member|Extent|Unit occurs in the south-western portion of the MOUNT DRUMMOND 1:250 000 mapsheet in the Northern Territory, [north of the Mitchiebo-Maloney fault].|
84111|Waterfall Member|Thickness range|Unit reaches up to approximately 750 m in thickness in the reference area (Rawlings et al, 2008).|
84111|Waterfall Member|Lithology|Lower portions of member comprise white, thickly bedded, medium- to coarse-grained cross-bedded sandstone, with current ripples and lineations, mudstone intraclasts, and pebbly layers. Overlying portions of member comprise laminated shale with thinly bedded siltstone and very fine-grained lithic sandstone interbeds, interbedded with medium to thick beds of white, cross-bedded, sublithic, medium- to coarse-grained sandstone. Also some rare chert and carbonate rocks (Rawlings et al, 2008).|
84111|Waterfall Member|Depositional environment|Unit represents a shallowing-upwards succession from basinal, through storm-dominated shelf, through to shoreface/marginal marine (Rawlings et al, 2008).|
84111|Waterfall Member|Relationships and boundaries|The stratigraphic relationship between the Waterfall Member (lower member of Fish Hole Formation) and the underlying units is not exposed. The member may unconformably overlie units of the Carrara Range Group. The member is conformably overlain by the Ten Mile Creek Member (previously known as part of the Top Lily Sandstone Member of the Playford Sandstone in Rawlings et al 2008), which forms the upper member of the Fish Hole Formation.|
84111|Waterfall Member|Identifying features|The Waterfall Member is very coarse-grained and quartzose, varying from very coarse-grained to granule-bearing, with a distinctive white colour (Rawlings et al, 2008).|
84111|Waterfall Member|Age reasons|Maximum depositional age derived from U-Pb SHRIMP dating of detrital zircons: Ten Mile Creek Member (formerly Top Lily Sandstone Member) of the Fish Hole Formation (formerly the Playford Sandstone) (stratigraphically overlies the Waterfall Member): GA sample 2786167 - 1656 ± 12 Ma (Kositcin and Carson, 2019). Ten Mile Creek Member (formerly Top Lily Sandstone Member) of the Fish Hole Formation (formerly the Playford Sandstone) (stratigraphically overlies the Waterfall Member): GA Sample 3305196 - 1641 ± 14 Ma (Kositcin et al, 2020). Drummond Formation of the Carrara Range Group (may stratigraphically underlie the Waterfall Member): GA Sample 2785617 - 1715 ± 30 Ma (Kositcin and Carson, 2019). Therefore, the potential depositional age range for the Waterfall Member can be considered to extend from ca. 1715 ± 30 Ma to 1641 ± 14 Ma.|
84111|Waterfall Member|Correlations|The Waterfall Member, based on similar maximum depositional age estimates with other units, can be correlated with the ungrouped Caulfield Formation and several other formations of the McNamara Group, including the Shady Bore Quartzite, the Bullrush Conglomerate and the Plain Creek Formation (Kositcin and Carson, 2019). The Waterfall Member may be correlative with components of the upper Glyde package (Rawlings, 1999) of the McArthur Basin.|
84111|Waterfall Member|Alteration and Mineralisation|The unit is highly ferruginised and manganiferous in places (Rawlings et al, 2008).|
84111|Waterfall Member|Geophysical Expression|Moderate magnetic response, likely due to the sandstone formations possessing “subtle magnetic layering” due to a high sedimentary iron content (Rawlings et al, 2008).|
84111|Waterfall Member|Comments|Note: Standard series 1: 100 000 and 1: 250 000 mapsheet names are shown in uppercase.|
84111|Waterfall Member|References|Carson, C. J., Kositcin, N., Anderson, J. R., and Henson, P. A. in prep. A revised Proterozoic tectono-stratigraphy of the South Nicholson region, Northern Territory, Australia - insights from SHRIMP U-Pb detrital zircon geochronology. Australian Journal of Earth Sciences. 
 **Kositcin N and Carson CJ, 2019. New SHRIMP U-Pb zircon ages from the South Nicholson and Carrara Range regions, Northern Territory. Geoscience Australia, Record 2019/09.  **Kositcin N, Carson CJ, Anderson JR, Doublier MP and Murr J, 2020. Exploring for the Future - New SHRIMP geochronology constraints on the basin evolution of the South Nicholson region. Geoscience Australia, Record 2020/025.  **Rawlings DJ, 1999. Stratigraphic resolution of a multiphase intracratonic basin system: the McArthur Basin, northern Australia. Australian Journal of Earth Sciences 46(5), 703-723.  **Rawlings DJ, Sweet IP and Kruse PD, 2008. Mount Drummond, NT (Second Edition). 1:250 000 Geological Map Series Explanatory Notes, Sheet SE 53-12. Northern Territory Geological Survey, Darwin, Northern Territory.  **Simmons JM, Williams B, Carson, C and Verdel C, 2023a. Mount Drummond, Northern Territory 1:250 000 Geological Map, Sheet SE 53-12 (Third Edition). Northern Territory Geological Survey, Darwin, Northern Territory.  **Simmons JM, Williams B, Carson, C and Verdel C, 2023b. Mount Drummond, Northern Territory 1:250 000 Geological Map Explanatory Notes, Sheet SE 53-12 (Third Edition). Northern Territory Geological Survey, Darwin, Northern Territory.  **Smith JW and Roberts HG, 1963a. Mount Drummond, NT (First Edition). 1:250 000 Geological Map Series Explanatory Notes, Sheet 53-12. Bureau of Mineral Resources, Canberra.  **Smith JW and Roberts HG, 1963b. Mount Drummond, NT (First Edition). 1:250 000 Geological Map Series, Sheet SE 53-12. Bureau of Mineral Resources, Canberra.  **Sweet IP, 1984. Carrara Range region, Northern Territory (First Edition). 1:100 000 geological map commentary, portions of 6360 and 6460. Bureau of Mineral Resources, Canberra.|07-OCT-23
24565|Wauchope Subgroup|Name source|Wauchope 1:100 000 Sheet area (sheet 5756), Bonney Well 1:250 000 Sheet area.|16-MAY-23
24565|Wauchope Subgroup|Constituents|From base to top, Unimbra Sandstone, Yeeradgi Sandstone, Newlands Volcanics, Arabulja Volcanics, Coulters Sandstone, Frew River Formation, and Kudinga Basalt. Contacts between formations generally conformable, but local unconformity exists at base of Coulters Sandstone.|16-MAY-23
24565|Wauchope Subgroup|Extent|Forms much of the Davenport and Murchison Ranges, cropping out in Bonney Well, Frew River, Barrow Creek,a nd Elkedra 1:250 000 Sheet area.|16-MAY-23
24565|Wauchope Subgroup|Thickness range|About 3500-4000 m.|16-MAY-23
24565|Wauchope Subgroup|Lithology|Lithic and/or feldspathic arenite, quartz arenite, and pebbly arenite which are commonly cross-bedded; felsic volcanics and basalt; minor slate, siltstone, limestone, dolostone.|16-MAY-23
24565|Wauchope Subgroup|Relationships and boundaries|Unconformable on Warramunga Group in north; conformable on Ooradidgee Subgroup of Hatches Creek Group, and basal formation (Urimbra Sandstone) interfingers locally ;with upper parts of Ooradidgee Subgroup. Overlain conformably by Hanlon Subgroup of Hatches Creek Group. Intruded by sill-like bodies of granophyre and rare dolerite. Unconformably overlain by Cambrian strata.|16-MAY-23
24565|Wauchope Subgroup|Age reasons|Younger than 1870 m.y. (U-Pb zircon age for volcanics in Warramunga Group), older than about 1640 m.y. (Rb-Sr whole-rock approximate age on Elkedra Granite, which intrudes Hatches Creek Group).|16-MAY-23
24565|Wauchope Subgroup|Defn author|Blake D.H., Stewart A.J., Sweet I.P., Wyche S., 1985|16-MAY-23
24565|Wauchope Subgroup|Comments|Remarks: Wauchope Subgroup is the middle of the three subgroups making up the Hatches Creek Group. It is more widespread than the underlying Ooradidgee Subgroup, and rests on basement where the Ooradidgee Subgroup is absent. In contrast to the interfingering volcanic and fluvial formations comprising the Ooradidgee Subgroup, it has a general layer-cake stratigraphy with only a minor degree of interfingering, and volcanics are less abundant. Sedimentary environments were mixed fluvial and near-shore marine. Its top is marked by an abrupt change from basaltic lavas to ridge forming sandstone of the overlying Hanlon Subgroup.|16-MAY-23
24565|Wauchope Subgroup|Defn Reference|86/25362|16-MAY-23
19716|Welltree Metamorphics|Name source|Welltree Station (130o32'00"E, 13o12'30"S on Reynolds River 1:100 000 Sheet (5071).|16-MAY-23
19716|Welltree Metamorphics|Unit history|1. Referred to by Berkman (1980) as undifferentiated quartz mica schist. 2. Represented on the 1980 BMR 1:500 000 geological map of the Pine Creek Geosyncline as undifferentiated schists.|16-MAY-23
19716|Welltree Metamorphics|Type section locality|Discontinuous outcrop of schist and gneiss approximately 3 km northwest of Wangi homestead on the Reynolds River 1:100 000 sheet. Outcrop extends in a northwest zone between 130o37'6"E, 13o07'00"S to the north and 130o37'24"E, 13o09'6"S to the south.|16-MAY-23
19716|Welltree Metamorphics|Extent|The unit forms very poor outcrop on the Darwin, Bynoe, Fog Bay, Reynolds River and Anson 1:100 000 sheet areas.|16-MAY-23
19716|Welltree Metamorphics|Thickness range|Unknown|16-MAY-23
19716|Welltree Metamorphics|Lithology|Quartz-feldspar-biotite-gneiss in places containing graphite and magnetite, quartz-feldspar mica schist, quartzitic gneiss. The schist and gneiss both commonly contain garnet and porphyroblasts of sillimanite or andalusite.|16-MAY-23
19716|Welltree Metamorphics|Relationships and boundaries|Lies to the west of low grade metasediments of the Burrell Creek Formation (contacts obscured). It is intruded by granite dated (using Rb/Sr method) at 1800 ma by R. Page (BMR) pers. Comm. Faulted to the west by Tom Turners Fault, against 1800 m.a. granite and undifferentiated gneiss. The southern extension is obscured by Cambrian sediments. The northern extension is obscured by cretaceous sediments. Members: Sweets Member - Marble, in places graphitic, para-amphibolite, diopside gneiss, quartz-feldspar biotite gneiss.|16-MAY-23
19716|Welltree Metamorphics|Age reasons|Early Proterozoic - 1. Age of the crustal formation of original components is 2150 +/- 40 M.a. (using Nd/Sm method) J de Laeter (W.A.I.T.) pers comm.; 2. Metamorphic event dated (using Rb/Sr method) at 1784 +/- 101 M.a. by J de Laeter (W.A.I.T.) pers comm; 3. Intruded by granite dated at 1800 M.a.|16-MAY-23
19716|Welltree Metamorphics|Proposed publication|Explanatory Notes, Bynoe 1:100 000 sheet area (Northern Territory Geological Survey)|16-MAY-23
80339|White Violet Orthogneiss|Name source|White Violet copper-tungsten mine (abandoned, 610130mE 7485790mN, GDA94, Zone53) in Jervois Range 1:100 000 mapsheet, Northern Territory.|16-MAY-23
80339|White Violet Orthogneiss|Unit history|Previously assigned as part of Mascotte Gneiss Complex of Shaw et al (1985) and Freeman et al (1986).|16-MAY-23
80339|White Violet Orthogneiss|Geomorphic expression|Prominent hills and ridges of boulders and tors in the Bonya Hills east of the Charlotte Fault Zone, and as occasional low, rounded outcrops in the plains between the Johannsen and Jervois ranges.|16-MAY-23
80339|White Violet Orthogneiss|Type section locality|Central Bonya Hills at 607837mE 7486133mN (GDA94, Zone53); access via private tracks.|16-MAY-23
80339|White Violet Orthogneiss|Extent|Common in Bonya Hills (around 607837mE 7486133mN); rare southeast of Jervois Range (at 635053mE 7499487mN).|16-MAY-23
80339|White Violet Orthogneiss|General description|Granodioritic to tonalitic gneiss, rare monzodiorite and quartz monzodiorite: fine- to medium-grained, equigranular to sparsely porphyritic, leucocratic with minor biotite; fresh to moderately weathered; foliated to gneissic with discontinuous cm-scale banding.|16-MAY-23
80339|White Violet Orthogneiss|Lithology|Granodioritic gneiss; compositionally banded with mm- to cm-scale thick bands that are discontinuous at the cm- to dm-scale; light-coloured bands are composed of medium-grained granoblastic plagioclase, dark bands are predominantly fine-grained granoblastic quartz; 1-2 vol% biotite, rare hornblende; accessory magnetite and rare titanite.|16-MAY-23
80339|White Violet Orthogneiss|Depositional environment|Continental margin environment, either arc cordillera or back arc basin, or derived from melting of pre-existing crust that formed in a continental margin environment.|16-MAY-23
80339|White Violet Orthogneiss|Relationships and boundaries|Interlayered with Mascotte Orthogneiss and Kings Legend Metadolerite; interpreted concordant intrusive contact with Bonya Metamorphics, intruded by Cappocks Granodiorite, Thring Granite and Samarkand Pegmatite.|16-MAY-23
80339|White Violet Orthogneiss|Identifying features|Distinctive rough surface weathering pattern in some outcrops that is reminiscent of chemical weathering normally associated with carbonate rocks.|16-MAY-23
80339|White Violet Orthogneiss|Structure and Metamorphism|Compositionally layered, weakly boudinaged, overprinted by layer-parallel grain shape foliation; intruded prior to regional, amphibolite-facies, high-thermal-gradient metamorphism.|16-MAY-23
80339|White Violet Orthogneiss|Age reasons|Crystallisation age of igneous protolith at 1794 ± 6 Ma (SHRIMP 207Pb/206Pb zircon age, Kositcin et al 2014).|16-MAY-23
80339|White Violet Orthogneiss|Correlations|Interpreted to be comagmatic and cogenetic with constituent units of the Casper Suite based on similar geochemical and isotopic composition, and timing of structural fabric development.|16-MAY-23
80339|White Violet Orthogneiss|Alteration and Mineralisation|Commonly chloritised and sericitised, locally silicified; no known economic mineralisation.|16-MAY-23
80339|White Violet Orthogneiss|Geophysical Expression|Magnetic low with locally developed magnetic high contact aureole; in area of gravity high; radiometric high signal.|16-MAY-23
80339|White Violet Orthogneiss|Geochemistry|Strongly metaluminous to strongly peraluminous I-type granodiorite, tonalite, monzodiorite and quartz-monzodiorite. Low to high LREE enrichment compared to the MREE; well-developed negative Eu anomalies.|16-MAY-23
80339|White Violet Orthogneiss|Defn author|Anett Weisheit, Barry Reno, Eloise Beyer (Northern Territory Geological Survey) 29-JUN-2018.|16-MAY-23
80339|White Violet Orthogneiss|References|Kositcin N, Beyer EE and Whelan JA, 2014. Summary of results. Joint NTGS-GA SHRIMP geochronology project: Arunta Region, July 2013-June 2014. Northern Territory Geological Survey, Record 2014008.  **Freeman MJ, Black LA, Offe LA, Senior BR, Shaw RD, Shergold JH, Simpson CJ, Walter MR, Warren RG, Donnellan N, Horsfall CJ, Laurie JR and Walley AM, 1986. Huckitta, Northern Territory (Second Edition). 1:250 000 geological map series, SF 53-11. Northern Territory Geological Survey, Darwin.  **Shaw RD, Warren RG and Freeman MJ, 1985. Stratigraphic definitions of named units in the Arunta Block, Northern Territory, 1979-82.  260|16-MAY-23
24572|Whites Formation|Name source|From "Whites Open Cut"; Grid reference 633178, Noonamah 1:100 000 Sheet (5172).|16-MAY-23
24572|Whites Formation|Unit history|Rock types of this unit were included by Malone (1962) in the Golden Dyke Formation and by Needham et al. (1980) in the Masson Formation.|16-MAY-23
24572|Whites Formation|Type section locality|Tight folding and poor exposure prevents defining a type section. Instead a type area is given 2 km by 2 km with centre of area having a grid reference 220540 on the Batchelor 1:100 000 Sheet (5171). Type area contains calcareous argillites, with rare stratiform stromatolites, carbonaceous and pyritic aragillites, minor calc-arenites, quaratzites and calcareous para-amphibolites.|16-MAY-23
24572|Whites Formation|Extent|Poorly exposed; outcrop mainly confined to an area 20 km by 5 km in the northwestern part of the Batchelor 1:100 000 Sheet (5171) and the southwestern part of the Noonamah 1:100 000 Sheet (5172).|16-MAY-23
24572|Whites Formation|Thickness range|Range 50 to 500 metres.|16-MAY-23
24572|Whites Formation|Lithology|Calcareous and/or pyritic carbonaceous argillite, calci- and dololutite, calcarenite, quartzite, calcareous para-amphibolite. The unit is characterised by the presence of generally fine grain detrital calcareous metapelites.|16-MAY-23
24572|Whites Formation|Relationships and boundaries|Conformably overlies Coomalie Dolomite (Malone, 1962) and is conformably overlain by Wildman Siltstone (Needham and Stuart-Smith, 1978). Base of unit defined by presence of metapelites and paucity of massive crystalline carbonate beds. Top of unit defined by calcareous metasediments, versus non-calcareous metapelites at base of Wildman Siltstone.|16-MAY-23
24572|Whites Formation|Age reasons|Part of Early Proterozoic metasedimentary sequence of the Pine Creek Geosyncline which overlies dated Archaean rocks (Page et al., 1980) and underlies the Kombolgie Formation which is locally the lowermost unit in the McArthur Basin Middle Proterozoic sequence.|16-MAY-23
24572|Whites Formation|Proposed publication|BMR Report|16-MAY-23
24572|Whites Formation|Proposer|Crick I.H.|16-MAY-23
24572|Whites Formation|Reserved? Yes/No|Originally reserved as Whites Member|16-MAY-23
24573|Wickstead Creek beds|Name source|Wickstead Creek (metric grid reference: 310000E, 7495000N)  which flows out of SE part of Reynolds Range in Aileron 1:100 000 Sheet area. The Wickstead Creek beds crop out in the hills west of the Creek where it debouches from the range on to the alluvial flat.|16-MAY-23
24573|Wickstead Creek beds|Type section locality|Point 293700E, 7505600N in bed of Wallaby Creek, E edge of Napperby 1:100 000 Sheet area - folded calc-silicate engulfed by Napperby Gneiss.|16-MAY-23
24573|Wickstead Creek beds|Extent|SE part of Reynolds Range in Aileron, Tea Tree, Reynolds Range, and Napperby 1:100 000 Sheet areas. Tawo parallel major outcrop belts have been mapped, one along S edge of Reynolds Range W of Wickstead Creek, the other to the N in the body of the Reynolds Range, extending E & W from the S vicinity of Mount Dunkin. The two belts are disrupted at W ends by Napperby Gneiss, and large masses of calc-silicate form a belt of remnants in Gneiss, and form an almost continuous string, suggesting that two belts were originally one belt, folded and later disrupted.|16-MAY-23
24573|Wickstead Creek beds|Thickness range|Unknown; no more than 1000 m (width of total outcrop).|16-MAY-23
24573|Wickstead Creek beds|Lithology|Interbedded and strongly folded calc-silicate rock (epidote-quartz, garnet-zoisite-diopside-quartz, epidote-garnet-calcite), diopside marble, biotite schist, biotite-sillimanite-quartz-plagioclase-microcline granofels.|16-MAY-23
24573|Wickstead Creek beds|Relationships and boundaries|In S part of Reynolds Range 1:100 0000 Sheet area, isolated outcrops of Wickstead Creek beds are interspersed with isolated outcrops of Lander Rock beds, and are therefore interpreted as a calcareous facies of, and interfingering with the Lander Rock beds. Wickstead Creek beds adjoin Mount Thomas Quartzite, but relationship not exposed. Elsewhere, Mount Thomas Quartzite unconformably overlies Lander Rock beds, and so presumably unconformably overlies Wickstead Creek beds. Intruded by Napperby Gneiss.|16-MAY-23
24573|Wickstead Creek beds|Identifying features|Reason for Proposed Name: A distinctive and easily mapped calc-silicate unit, very different from adjoining granulites, granites, and gneisses of metapelitic character.|16-MAY-23
24573|Wickstead Creek beds|Age reasons|If correlation with Lander Rock beds is correct, Wickstead Creek beds were deposited in Early Proterozoic (or earlier). Are older than Napperby Gneiss which is dated at 1800-1500 m.y. by Rb-Sr muscovite and whole rock (L P Black, BMR, pers. comm., 1975).|16-MAY-23
24573|Wickstead Creek beds|Proposed publication|1. 'Geology of NW Arunta Block, NR' - BMR Publication.  2. 'Stratigraphic definitions in Arunta Block' - BMR Microfiche Report.|16-MAY-23
24573|Wickstead Creek beds|Defn Reference|80/20787|16-MAY-23
24573|Wickstead Creek beds|Reserved? Yes/No|Yes|16-MAY-23
24573|Wickstead Creek beds|Unit name|Wickstead Creek Beds|16-MAY-23
37739|Wild Cow Subgroup|Name source|Wild Cow Creek, which drains south from the western Carrara Range in the Mount Drummond 1:250 000 map sheet (latitude 18o38'S longitude 137o25'E).|16-MAY-23
37739|Wild Cow Subgroup|Unit history|Parts of Constance Sandstone and Mullera Formation as mapped by Smith and Roberts (1963), and subsequently by Sweet (1984). These two formations are substantially revised on the second edition of Mount Drummond geological map (Rawlings et al in prep).|16-MAY-23
37739|Wild Cow Subgroup|Constituents|Includes the Playford and Bowgan Sandstones, and the overlying Crow Formation.|16-MAY-23
37739|Wild Cow Subgroup|Geomorphic expression|Resistant ridge-forming basal part (sandstone-dominated units) and recessive upper part (siltstone and shale-dominated unit).|16-MAY-23
37739|Wild Cow Subgroup|Type section locality|As defined for each constituent formation. The reference section provides a convenient location for an overview of the Subgroup.|16-MAY-23
37739|Wild Cow Subgroup|Extent|Western half of Mount Drummond 1:250 000 sheet area.|16-MAY-23
37739|Wild Cow Subgroup|Thickness range|Up to 4500 m thick in western MOUNT DRUMMOND.|16-MAY-23
37739|Wild Cow Subgroup|Lithology|Mixed sequence of sandstone, siltstone, shale and minor conglomerate and rare carbonate rocks.|16-MAY-23
37739|Wild Cow Subgroup|Relationships and boundaries|Unconformably overlies Murphy Metamorphics, McNamara and Benmara Groups. The contact with the Benmara Group is poorly exposed and the relationship cannot be resolved with any certainty. Rawlings et al (in prep) favour a partly reactivated unconformity. Disconformably overlain by Accident Subgroup, except in the west where the contact with Mittiebah Sandstone may be conformable. Locally, unconformably overlain by Georgina Basin succession. Parent units: Lower of two subgroups forming the South Nicholson Group.|16-MAY-23
37739|Wild Cow Subgroup|Age reasons|Meaningful radiometric dating is currently unavailable for any part of the South Nicholson Group (SNG) and its age is therefore internally unconstrained. The maximum age of 1595+/-6 Ma is that of the Lawn Hill Formation at the top of the immediately underlying McNamara Group (Page and Sweet 1998). There are no minimum age constraints imposed by overlying units, apart from the late Neoproterozoic to Phanerozoic Georgina Basin. The interpreted age range of the whole SNG, and by default for the Wild Cow Subgroup, of 1500 to 1400 Ma, is based on correlation of the SNG with the Roper Group of the southern McArthur Basin. These two groups, combined, make up the Roper superbasin (Jackson et al 1999, Abbott et al 2001).|16-MAY-23
37739|Wild Cow Subgroup|Correlations|Lower Roper and Renner Groups and possibly Caulfield beds.|16-MAY-23
37739|Wild Cow Subgroup|Defn author|Rawlings, D.J. [approved 11-APR-2005]|16-MAY-23
37739|Wild Cow Subgroup|Comments|This package of rocks has been accorded subgroup status because a disconformity, locally an angular unconformity, has been recognised within the South Nicholson Group. The Wild Cow Subgroup constitutes all of the SNG below that unconformity. The upper SNG (the Accident Creek Subgroup) also has distinctly different facies patterns and depocentres from the Wild Cow Subgroup. Reference section: A composite section from south to north in the Mitchiebo Waterhole area provides a convenient representation of the Subgroup. It includes the Playford Sandstone type section (see that definition for details), and a separate segment covering the Crow Formation, around latitude 18o39'S longitude 137o6'E: from Mitchiebo Waterhole, at 721222E 7937170N (base), for 1.8 km to the northeast, to 722522E 7938570N (top). Note: All locations are based on the GDA94 geodetic datum. Standard series 1:250 000 sheet names are shown in upper case.|16-MAY-23
37739|Wild Cow Subgroup|References|**ABBOTT S.T., Sweet I.P., Plumb K.A., Young D.N., Cutovinos A., Ferenczi P.A., Brakel A. and Pietsch B.A., 2001. Roper region: Urapunga and Roper River special, Northern Territory (Second Edition); 1:250 000 Geological Map Series, sheets SD53-10,11. Northern Territory Geological Survey-Australian Geological Survey Organisation (NGMA), Map and Explanatory Notes.   **JACKSON M.J., Sweet I.P., Page R.W. and Bradshaw B.E., 1999. The South Nicholson and Roper Groups: evidence for the early Proterozoic Roper Superbasin. In: Bradshaw B.E. and Scott D.L. (Eds.), Integrated basin analysis of the Isa Superbasin using seismic, well-log and geopotential data: an evaluation of the economic potential of the northern Lawn Hill Platform. Australian Geological Survey Organisation, Record 1999/19 (unpaginated).    **PAGE R.W. and Sweet I.P., 1998. Geochronology of basin phases in the western Mount Isa Inlier, and correlation with the McArthur Basin. Australian Journal of Earth Sciences, 45, 2; 219-232.  **RAWLINGS D.J. Sweet I.P. and Kruse P.D., in prep [2008]. Mount Drummond, Northern Territory (Second Edition); 1:250 000 Geological Map Series, sheet SE53-12. Northern Territory Geological Survey, Map and Explanatory Notes.    **SMITH J.W. and Roberts H.G., 1963. Mount Drummond, N.T. (First Edition); 1:250,000 geological series, sheet SE53-12. Bureau of Mineral Resources, Geology and Geophysics, Map and Explanatory Notes.  **SWEET I.P., 1984. Carrara Range region, Northern Territory (First Edition); 1:100,000 geological series, portions of sheets 6460 and 6360. Bureau of Mineral Resources, Geology and Geophysics, Explanatory Notes.|16-MAY-23
72416|Windajong Granite|Name source|After Mount Windajong (53K 279750mE 7672675mN) in WILLOWRA|16-MAY-23
72416|Windajong Granite|Unit history|Mapped as unnamed Carpentarian granite Pg on First Edition MOUNT PEAKE (Offe 1978).|16-MAY-23
72416|Windajong Granite|Geomorphic expression|Low whalebacks.|16-MAY-23
72416|Windajong Granite|Type section locality|Approximately 2 km southeast of Mount Windajong at 281500mE 7671500mN (21o02'34"S 132o53'55"E) in WILLOWRA.|16-MAY-23
72416|Windajong Granite|Extent|A few outcrops scattered over an area of ~40 km2 in north-central MOUNT PEAKE. The granite has a distinctive geophysical expression and defines a subcircular non-magnetic gravity low extending over an area of ~160 km2, which extends from MOUNT PEAKE to extreme south-central LANDER RIVER.|16-MAY-23
72416|Windajong Granite|Lithology|Evenly grained to seriate porphyritic two-mica granite.|16-MAY-23
72416|Windajong Granite|Relationships and boundaries|Inferred from airborne magnetic and regional gravity data to intrude Lander Rock Formation, but contacts not exposed.|16-MAY-23
72416|Windajong Granite|Age reasons|Statherian, based on SHRIMP single-crystal zircon U-Pb igneous crystallisation age of 1730 ± 3 Ma (Cross et al 2005).|16-MAY-23
72416|Windajong Granite|Correlations|Possible constituent of Devils Suite of Tennant Region.|16-MAY-23
72416|Windajong Granite|References|Cross A, Claoué-Long JC, Scrimgeour IR, Crispe A and Donnellan N, 2005. Summary of results. Joint NTGS-GA geochronology project: northern Arunta and Tanami regions 2000-2003. Northern Territory Geological Survey, Record 2005-003.Offe LA, 1978. Mount Peake, Northern Territory. 1:250 000 geological series explanatory notes, SF 53-5. Bureau of Mineral Resources, Australia, Canberra.|16-MAY-23
79223|Winnall Group|Name source|Named after Winnall Ridge in LAKE AMADEUS (GDA94 53K 734373mE 7258954mN) by Ranford et al., (1965).|16-MAY-23
79223|Winnall Group|Unit history|Replaces the former Winnall Beds of Ranford et al (1965), an informal unit that is now divided into a number of discrete units (see below).|16-MAY-23
79223|Winnall Group|Constituents|Breaden, Gloaming, Froud, Liddle and Puna Kura Kura formations; and Chookla Member of the Puna Kura Kura Formation.|16-MAY-23
79223|Winnall Group|Geomorphic expression|Ridge-forming sandstone and recessive siltstone.|16-MAY-23
79223|Winnall Group|Type section locality|The original informal type area for Winnall beds was in the Liddle Hills in southwestern HENBURY (SG53-01) (Ranford et al, 1965). Only the upper part of Winnall Group is now considered to be exposed there (ie Liddle and Puna Kura Kura formations; and Chookla Member), and there is no single type section for the entire succession currently recognised. Type localities for the other constituent formations are: (1) Breaden Formation around GDA94 53J 309702mE 7247490mN (133.1163deg E -24.8579deg S) along the axis of the Mill Ridge anticline in southeastern HENBURY; (2) Gloaming Formation (a) around GDA94 53J 308614mE 7276909mN (133.10952deg E, -24.61009deg S) ~5 km southwest of Henbury Meteorite Craters, and (b) GDA94 53J 277095mE 7261395mN (132.79591deg E, -24.74587deg S) at the western end of the Seymour Range; and (3) Froud Formation (a) GDA94 53J 286499mE 7276995mN (132.8919 deg E,  -24.6039deg S) (lower contact) to GDA94 53J 285973mE 7276891mN (132.8860deg E, -24.6073deg S) (upper contact) situated immediately south of Dead Bullock Plain, and (b) GDA94 53J 331094mE 7256130mN (133.3290deg E, -24.8003deg S) (base) to GDA94 53J 331449mE 7255587mN (133.3246deg E,  -24.8052deg S) in a range of hills paralleling the southern bank of the east-flowing Froud River.|16-MAY-23
79223|Winnall Group|Extent|Widespread, crops out in FINKE, KULGERA, AYERS ROCK, HENBURY, LAKE AMADEUS, and BLOODS RANGE 1:250 000 mapsheets, mainly south of the `Central Ridge¿ in the Amadeus Basin but onlaps this ridge in the HENBURY mapsheet. Former Winnall beds in MOUNT RENNIE are now reassigned to Maurice Formation or Ellis Sandstone (Close et al, 2004).|16-MAY-23
79223|Winnall Group|Thickness range|1300 m in the original type locality in the Liddle Hills; a minimum exposed thickness of 1524m has been estimated (Edgoose 2013), and Wells et al., (1970) suggested a maximum thickness of 2154m (7000 ft). Thickness varies substantially but Winnall Group is considered to generally thicken to the southwest.|16-MAY-23
79223|Winnall Group|Lithology|Sandstone: feldspathic, subarkosic, arkosic and quartz arenite; and siltstone.|16-MAY-23
79223|Winnall Group|Depositional environment|Mainly shallow-marine to intertidal.|16-MAY-23
79223|Winnall Group|Fossils|Ichnofossils: cf Syringiomorpha nathorst (Wells et al 1970); and probable Bunyerichnus dalgarnoi.|16-MAY-23
79223|Winnall Group|Diastems or hiatuses|Likely includes the Precambrian/Cambrian boundary. [but not as a diastem or hiatus]|16-MAY-23
79223|Winnall Group|Relationships and boundaries|Sits stratigraphically between the Inindia beds and the Pertaoorrta Group. Unconformably overlies Inindia beds and Bitter Springs Formation; and is unconformably overlain by the Mount Currie Conglomerate, Cleland, Stairway and Carmichael sandstones, Polly Conglomerate and Langra Formation (Edgoose 2013). It also unconformably or disconformably overlies the Aralka Formation in HENBURY.|16-MAY-23
79223|Winnall Group|Structure and Metamorphism|Folded and faulted, but relatively unmetamorphosed.|16-MAY-23
79223|Winnall Group|Age reasons|Correlation in part with both Pertatataka Formation and Arumbera Sandstone suggests an Ediacaran to early Cambrian age.|16-MAY-23
79223|Winnall Group|Correlations|Correlated with the Pertatataka Formation (Wells et al 1964, 1966, 1979); and in part with the Carnegie Formation, Ellis Sandstone, Sir Fredrick Conglomerate and Maurice Formation (Haines et al 2010). In part also correlated with the lower Pioneer Sandstone (Grey and Blake 1999).|16-MAY-23
79223|Winnall Group|Geophysical Expression|Typically linear, low Total Magnetic Intensity response.|16-MAY-23
79223|Winnall Group|Defn author|N Donnellan, VJ Normington 21-FEB-2017|16-MAY-23
79223|Winnall Group|References|Close DF, Scrimgeour IR and Edgoose CJ, 2004b. Mount Rennie, Northern Territory. 1:250 000 geological map series, SF 52-15. Northern Territory Geological Survey, Darwin.***Edgoose CJ, 2013. Amadeus Basin; in Ahmad M and Munson TJ (compilers) 'Geology and mineral resources of the Northern Territory'. Northern Territory Geological Survey, Special Publication 5.***Grey K and Blake DH, 1999. Neoproterozoic (Cryogenian) stromatolites from the Wolfe Basin, east Kimberley, Western Australia: correlation with the Centralian Superbasin. Australian Journal of Earth Sciences 46(3), 329-341. ***Haines PW, Allen HJ and Grey K, 2010. Reassessment of the geology and exploration potential of the Western Australian Amadeus Basin. IN GSWA 2010 extended abstracts: promoting the prospectivity of Western Australia. Geological Survey of Western Australia, Record 2010/2, p27-29. ***Ranford LC, Cook PJ and Wells AT, 1965. The geology of the central part of the Amadeus Basin, Northern Territory. Bureau of Mineral Resources, Australia, Report 86.***Wells AT, Forman DJ and Ranford LC, 1964. Geological reconnaissance of the Rawlinson and Macdonald 1:250 000 sheet areas, Western Australia. Bureau of Mineral Resources, Australia, Report 65.***Wells AT, Stewart AJ and Skwarko SK, 1966. Geology of the south-eastern part of the Amadeus Basin, Northern Territory. Bureau of Mineral Resources, Australia, Report 88.***Wells AT, Forman DJ, Ranford LC and Cook PJ, 1970. Geology of the Amadeus Basin, Central Australia. Bureau of Mineral Resources, Australia, Bulletin 100.|16-MAY-23
69133|Wonarah Formation|Name source|From Wonarah Telegraph Repeater Station and Wunara community, on Barkly Highway in southwestern RANKEN (Smith 1972: 76).|16-MAY-23
69133|Wonarah Formation|Unit history|Alroy Downs beds of David (1932), Wonarah beds of Öpik (1956b), Alexandria beds of Öpik (1956b) in part, Burton beds of Smith and Roberts (1963).|16-MAY-23
69133|Wonarah Formation|Geomorphic expression|Low hills and plateau cappings to not exposed.|16-MAY-23
69133|Wonarah Formation|Type section locality|Unit stratotype at 174.0-319.6 m depth in cored drillhole NTGS01/1 (eastern RANKEN; Kruse 2003). Lower boundary at disconformity with underlying Thorntonia Limestone, at sharp change from light grey dolosparstone below into mid-grey, impure, bioclast-bearing marly laminite above. Upper boundary at conformable contact with overlying Camooweal Dolostone, at sharp change from mid-grey dolomudstone below into thin mid-grey phosclast conglomerate above.|16-MAY-23
69133|Wonarah Formation|Extent|Undilla Sub-basin and Alexandria-Wonarah Basement High in central Georgina Basin: AVON DOWNS, RANKEN, MOUNT DRUMMOND, FREW RIVER, ALROY, BRUNETTE DOWNS; possibly subsurface in western URANDANGI, western MOUNT ISA, western CAMOOWEAL, southwestern LAWN HILL.|16-MAY-23
69133|Wonarah Formation|Thickness range|Drillhole thicknesses: 145.6 m in type section, 191+ m in NTGS00/1, estimated 118 m in BMR Cattle Creek 1, estimated 119-141 m in Lake Nash 1.|16-MAY-23
69133|Wonarah Formation|Lithology|Silty dolostone, calci/dolomudstone and siliciclastic mudstone interbeds, micaceous siltstone; minor intraclast and bioclast wacke- to grainstone; basal carbonaceous marly laminite.|16-MAY-23
69133|Wonarah Formation|Depositional environment|Subtidal marine.|16-MAY-23
69133|Wonarah Formation|Relationships and boundaries|Disconformably overlies Thorntonia Limestone (early Middle Cambrian) or where this is absent, unconformably overlies Helen Springs Volcanics and correlative Peaker Piker Volcanics (late Early Cambrian) or where these are absent, unconformably overlies Mesoproterozoic Renner Group and correlative South Nicholson Group. Passes laterally into Anthony Lagoon beds to west. Conformably overlain by Ranken Limestone and Camooweal Dolostone. Parent unit: Barkly Group.|16-MAY-23
69133|Wonarah Formation|Age reasons|Middle Cambrian: late Templetonian-?Floran, based on abundant trilobite fauna (Gravestock and Shergold 2001, Laurie 2004a).|16-MAY-23
69133|Wonarah Formation|Correlations|Anthony Lagoon beds of Barkly Sub-basin; Inca Formation, Gowers Formation, Beetle Creek Formation, Currant Bush Limestone, Blazan Shale of Undilla Sub-basin; lower Arthur Creek Formation of southern Georgina Basin.|16-MAY-23
69133|Wonarah Formation|Comments|The complete intersection of this unit in cored drillhole NTGS01/1 together with its immediately underlying and overlying formations provides a suitable type section and permits formalisation of Wonarah beds as Wonarah Formation.|16-MAY-23
23244|Woodah Sandstone|Name source|Woodah Island (lat. 13o 30'S, long. 136o 09'E), BLUE MUD BAY.|16-MAY-23
23244|Woodah Sandstone|Unit history|Formerly mapped as part of the now abandoned 'Groote Eylandt beds' (Plumb and Roberts, 1965).|16-MAY-23
23244|Woodah Sandstone|Geomorphic expression|Prominent joint-controlled, bare rocky outcrops.|16-MAY-23
23244|Woodah Sandstone|Type section locality|Lower boundary stratotype: Western sides of Morgan Island, lat. 13o 28'S, long. 136o 05'E (GR PF183105).|16-MAY-23
23244|Woodah Sandstone|Extent|Eastern BLUE MUD BAY. Main outcrops on Morgan Island, Burney and northern Bickerton Islands, Isle Woodah, Grindall Point and near Cape Barrow.|16-MAY-23
23244|Woodah Sandstone|Thickness range|Thickest exposure is 50-60m at Morgan Island, where the top is eroded.|16-MAY-23
23244|Woodah Sandstone|Lithology|Isle Woodah- sandstone: pink and white, medium-grained, medium- to thick-bedded, flat- to cross-bedded, quartz rich. Burney Island- basal cobble to boulder conglomerate: polymict, interbedded with coarse- to very coarse-grained, pebbly sandstone. Bickerton Island- lower unit of mudstone: red-brown, micaeous, interbedded with medium- to coarse-grained snadstone, thin-bedded, ripples, desiccation crack. Upper unit of sandstone: white to pink, medium-grained, quartz-rich matrix, larger clasts polymict. Cape Barrow- sandstone: coarse-grained and pebbly, grades into conglomerate: medium-bedded, cross-bedded, quartz-rich matrix, larger clasts polymict.|16-MAY-23
23244|Woodah Sandstone|Relationships and boundaries|Assigned to the base of the Alyangula Subgroup of the Groote Eylandt Group. Lies unconformably on Grindall Formation and it intrusives (Bradshaw Complex and Bukudal Granite). Outcrops tentatively indentified as Woodah Sandstone are inferred to be overlain by Bartalumba Basalt on eastern Bickerton Island, although the contact is not exposed.|16-MAY-23
23244|Woodah Sandstone|Age reasons|Probably Statherian (Palaeoproterozoic), but not well constrained. A maximum constraint is provided by the ~1815 Ma age of the Bickerton Rhyolite (Pietsch et al. 1994), near the base of the underlying Bustard Subgroup.|16-MAY-23
23244|Woodah Sandstone|Correlations|Considered to be a lateral equivalent of the Alyinga Sandstone.|16-MAY-23
72422|Woodalla Member|Name source|After Woodalla Bore (53K 193000mE 7575250mN) in GILES.|16-MAY-23
72422|Woodalla Member|Unit history|Mount Stafford beds (Shaw and Stewart 1975) in part.|16-MAY-23
72422|Woodalla Member|Geomorphic expression|Locally forms prominent ridges, but generally poorly outcropping.|16-MAY-23
72422|Woodalla Member|Type section locality|Around 225300mE 7571300mN (21o56'23"S 132o20'30"E) to north of Giles Range in GILES.|16-MAY-23
72422|Woodalla Member|Extent|Principal areas of outcrop immediately north of Giles Range in southwestern MOUNT PEAKE, and near Tin Bore (249700mE 7562100mN) in central-northern NAPPERBY.|16-MAY-23
72422|Woodalla Member|Thickness range|Polydeformation precludes precise determination, but estimated to be at least 500 m, although probably substantially thicker.|16-MAY-23
72422|Woodalla Member|Lithology|Metasedimentary feldspathic quartzarenite; (cleaved) siltstone and schistose equivalents. Stratiform ortho-amphibolite is associated with schistose Woodalla Member near Tin Bore in NAPPERBY.|16-MAY-23
72422|Woodalla Member|Depositional environment|Deep-water marine, turbiditic.|16-MAY-23
72422|Woodalla Member|Relationships and boundaries|Base not exposed. Laterally equivalent to Mount Stafford Member near Tin Bore in NAPPERBY. However, Mount Stafford Member is a higher metamorphic-grade equivalent of Woodalla Member.|16-MAY-23
72422|Woodalla Member|Structure and Metamorphism|Polydeformed, with generally moderately to steeply dipping bedding or S1 foliation.|16-MAY-23
72422|Woodalla Member|Age reasons|Late Orosirian. Correlative Mount Stafford Member has maximum age of sedimentation of 1869 Ma based on its youngest coherent group of detrital zircons, 1866 ± 3 Ma (Claoué-Long et al in press). Correlative Lander Rock Formation in MOUNT DOREEN has similar maximum age of sedimentation, ie 1868 Ma based on youngest coherent group of detrital ages of 1862 ± 6 Ma (Claoué-Long et al in press).|16-MAY-23
72422|Woodalla Member|Correlations|Correlated with turbiditic (and locally high-grade equivalent) undivided Lander Rock Formation in MOUNT DOREEN and with Mount Stafford Member in MOUNT PEAKE and NAPPERBY. Woodalla Member may correlate with widespread (probably turbiditic) undivided Lander Rock Formation in western Aileron Province of Arunta Region.|16-MAY-23
72422|Woodalla Member|References|Claoué-Long JC, Edgoose C and Worden KE, in press. A correlation of Arunta Region stratigraphy in central Australia. Precambrian Research.Shaw RD and Stewart AJ, 1975. Arunta Block - regional geology: in Knight CL (editor) `Economic geology of Australia and Papua New Guinea'. Australasian Institute of Mining and Metallurgy, Monograph 5, 437-442.|16-MAY-23
24584|Woodforde River beds|Name source|Woodforde River (metric grid reference: 307000E, 7508000N), which flows down a valley cut in the Woodforde River beds in SE part of Reynolds Range, Tea Tree and Aileron 1:100 000 Sheet areas.|16-MAY-23
24584|Woodforde River beds|Type section locality|Point 301800E, 7508700N, in bed of Woodforde River, Aileron 1:100 000 Sheet area, 2.2 km N of Mt Dunkin; clean exposure of marble and calc-silicate rocks, folded and disrupted; also on NE bank of river ~100 m upstream (NW-wards). |16-MAY-23
24584|Woodforde River beds|Extent|SE part of Reynolds Range, in upper reaches of Woodforde River in Aileron and Tea Tree 1:100 000 Sheet area.|16-MAY-23
24584|Woodforde River beds|Thickness range|Unknown; no more than about 1000 m (width of total outcrop).|16-MAY-23
24584|Woodforde River beds|Lithology|Diopside marable, forsterite marble, tremolite marble, garnet-epidote-diopside-plagioclase-microcline rock, biotite-muscovite-epidote-plagioclase-microcline-quartz rock, magnetite-hornblende-cummingtonite-oligoclase rock, para-amphibolite, chlorite schist, phlogopite marble. Thin interbeds of quartzite and sillimanite schist in west part of outcrop.|16-MAY-23
24584|Woodforde River beds|Relationships and boundaries|Adjoins with apparent conformity metapelitic granulite, but along strike to NW where metamorphic grade lessens, facings in same Pine Hill outcrop indicate it underlies Woodforde River beds. Top of Woodforde River beds not preserved, because it occupies core of syncline. Occupies similar stratigraphic position to Algamba Dolomite Member of Pine Hill Formation, and so is correlated with Algamba Dolomite Member. Continuity of outcrop between Woodforde River beds and Algamba Dolomite Member not preserved (if it ever existed). Intruded by unnamed granite which may be off-shoot of Napperby Gneiss.|16-MAY-23
24584|Woodforde River beds|Identifying features|Reason for Proposed Name: A distinctive and readily mapped unit in Reynolds Range, and markedly different in mineralogical composition from adjoining metapelitic granulites.|16-MAY-23
24584|Woodforde River beds|Age reasons|Time of deposition unknown, almost certainly same as Algamba Dolomite Member, I.e. Early Proterozoic or older, but no evidence for or against this) - see submission on Pine Hill Formation and Algamba Dolomite Member. Time of metamorphism not known with certainty, presumably late Early or early Middle Proterozoic. Older than granite intruding it, and certainly older than Napperby Gneiss, which intrudes Pine Hill Formation nearby and is dated at 1800-1500 m.y. (L P Black, BMR, pers. comm., 1975).|16-MAY-23
24584|Woodforde River beds|Proposed publication|1. 'Geology of NW Arunta Block' - BMR Publication. 2. 'Stratigraphic definitions in Arunta Block' - BMR Microfiche Report|16-MAY-23
24584|Woodforde River beds|Defn Reference|80/20787|16-MAY-23
24584|Woodforde River beds|Proposer|Stewart A.J.|16-MAY-23
24584|Woodforde River beds|Reserved? Yes/No|Yes|16-MAY-23
28280|Woodgreen Granite Complex|Name source|After 'Woodgreen' homestead just west of outcrop area. Granite also within station. 'Woodgreen' homestead is just east of the Ammaroo Reef Road, Alice Springs Region, in the central part of the Alcoota 1:250 000 Sheet area, SF 53-10, Australian Map Grid.|16-MAY-23
28280|Woodgreen Granite Complex|Type section locality|In centre of Sheet area 4 km southwest of West Bore in tors beside track. Centred on GR 433E, 7519 N, zone 53, AMG (metric). Euhedral to subhedral microcline phenocrysts in a grey aphanitic matrix.|16-MAY-23
28280|Woodgreen Granite Complex|Extent|From Boomerang Bore (GR 430E, 75145N AMG - metric), 'Woodgreen' Station 25 km northwards to the foothills of Mount Skinner.|16-MAY-23
28280|Woodgreen Granite Complex|Lithology|Porphyritic biotite gneissic granite, biotite adamellite, hornblende-adamellite, garnet-bearing granite.|16-MAY-23
28280|Woodgreen Granite Complex|Relationships and boundaries|Intrudes the Delny Gneiss: Unconformably overlain by the Central Mount Stewart Beds and possibly by the Grant Bluff Formation.|16-MAY-23
28280|Woodgreen Granite Complex|Proposed publication|BMR Report|16-MAY-23
28280|Woodgreen Granite Complex|Comments|Poorly foliated in comparison with other granites in the Sheet area.|16-MAY-23
28280|Woodgreen Granite Complex|Name first published by|Shaw R.D., Warren R.G., Kopras J., Green D.E., 1975|16-MAY-23
28280|Woodgreen Granite Complex|Unit name|Woodgreen Granite Complex (Pgw)|16-MAY-23
75946|Woolianna Gabbro|Name source|After Woolianna homestead, Woolianna Road and Woolianna school 5 km north of Daly River township, Northern Territory, Pine Creek 1:250 000 mapsheet, Daly River 1:100 000 mapsheet, Litchfield Province, Pine Creek Orogen, Northern Territory.|16-MAY-23
75946|Woolianna Gabbro|Unit history|Previously known as Wangi Basics, first used by Needham and Stuart-Smith (1984) and formally defined in Dundas et al (1987). The name Wangi Basics is abandoned, as it is now known to comprise distinct geochemical groups which are genetically unrelated.|16-MAY-23
75946|Woolianna Gabbro|Geomorphic expression|Large stock in Moyle and Wingate Mountains 1:100 000 mapsheets and scattered outcrops in Daly River, Greenwood and Reynolds river 1:100 000 mapsheets.|16-MAY-23
75946|Woolianna Gabbro|Type section locality|Large outcrop exposure on Moyle and Wingate Mountains 1:100 000 mapsheets 40 km southwest of Daly River township (GDA 94 52L 663172mE 8442583mN 14°4'59"S 130°30'41"E)|16-MAY-23
75946|Woolianna Gabbro|Description at type locality|Large area of good exposure comprising metamorphosed medium- to coarse-grained, variably altered, equigranular rocks that include gabbro, hypersthene gabbro and microgabbro to coarse-grained dolerite.|16-MAY-23
75946|Woolianna Gabbro|Extent|Has surface exposures in Moyle, Greenwood, Wingate Mountains, Daly River and Reynolds River 1:100 000 mapsheets.|16-MAY-23
75946|Woolianna Gabbro|General description|Occurs as a large stock covering an area of 28 km2 (Edgoose et al 1989) in Wingate Mountains and Moyle 1:100 000 mapsheets, and also occurs as scattered exposures in Reynolds River, Greenwood and Daly River 1:100 000 mapsheets. Unifying characteristic is distinctive back-arc basin geochemical signature.|16-MAY-23
75946|Woolianna Gabbro|Thickness range|Area of large stock in Wingate Mountains 1:100,000 mapsheet is  about 28 km2 (Edgoose et al 1989)|16-MAY-23
75946|Woolianna Gabbro|Lithology|In Wingate Mountains 1:100,000 mapsheet, Woolianna Gabbro comprises metamorphosed medium- to coarse-grained, variably altered, equigranular rocks which include gabbro, hypersthene gabbro and microgabbro to coarse-grained dolerite. In Daly River 1:100,000 mapsheet, it comprises metaperidotite, metapyroxenite, metaharzburgite, amphibolite, metadolerite and metabasalt.|16-MAY-23
75946|Woolianna Gabbro|Depositional environment|Genesis: Intrusive rocks related to island-arc/back-arc basin setting.|16-MAY-23
75946|Woolianna Gabbro|Relationships and boundaries|Contact relationships between the large stock and surrounding rock units are not known. Edgoose et al (1989) inferred that the stock most likely intrudes nearby Hermit Creek Metamorphics, Burrell Creek Formation and Berinka Volcanics. Mafic xenoliths in adjacent Murra-Kamangee Granodiorite are thought to be of Woolianna Gabbro (former Wangi Basics; Edgoose et al 1989).|16-MAY-23
75946|Woolianna Gabbro|Identifying features|Woolianna Gabbro is metamorphosed to amphibolite facies with overprinting greenschist-facies retrogression. It is characterised by a distinctive island arc (back-arc basin) chemical signature which is most apparent in DALY RIVER (Glass 2007).|16-MAY-23
75946|Woolianna Gabbro|Structure and Metamorphism|Amphibolite-facies metamorphism with greenschist-facies retrogressive overprint.|16-MAY-23
75946|Woolianna Gabbro|Age reasons|Not adequately constrained, but believed to be in range1860-1855 Ma (Glass 2010) based on stratigraphic constraints.|16-MAY-23
75946|Woolianna Gabbro|Correlations|Possible correlative of Tickalara Metamorphics in Central Zone of Halls Creek Orogen, Western Australia (Sheppard et al 1999)|16-MAY-23
75946|Woolianna Gabbro|Alteration and Mineralisation|Localised chlorite and sericite alteration. A minor occurrence of shear-zone-hosted polymetallic Cu-Pb-Zn-Ag veins occurs at MGA94 Zone 52 682030mE 8492161mN (13°38'1"S 130°40'58"E) in Daly River 1:100 000 mapsheet (Ferenczi 1990, NTGS MODAT database).|16-MAY-23
75946|Woolianna Gabbro|Geophysical Expression|Large stock on Wingate Mountains 1:100 000 mapsheet has strong magnetic response.|16-MAY-23
75946|Woolianna Gabbro|Geochemistry|Woolianna Formation rocks are characterised by a distinctive island-arc (back-arc basin) chemical signature (Glass 2007) which is further reinforced by positive epsilonNd isotopic signatures (Glass 2010).|16-MAY-23
75946|Woolianna Gabbro|References|DUNDAS DL, Edgoose CJ, Fahey GM and Fahey JE, 1987. Daly River 1:100 000 Geological Map Series. Northern Territory Geological Survey Explanatory Notes (5070).  **EDGOOSE CJ, Fahey GM and Fahey JE, 1989. Wingate Mountains 1:100 000 Geological Map Series. Northern Territory Geological Survey Explanatory Notes (5069).  **FERENZI PA, 1990. The Daly River Mineral Field. NTGS Technical Report 1990-017, Northern Territory Geological Survey.  **GLASS LM, 2007. Geochemistry of mafic rocks in the Litchfield Province, western Pine Creek Orogen: Evidence for a Palaeoproterozoic arc-related setting and links to the Halls Creek Orogen: in 'Annual Geoscience Exploration Seminar (AGES) 2007. Record of Abstracts.' Northern Territory Geological Survey, Record 2007 001.  **GLASS LM, 2010. Palaeoproterozoic island-arc-related rocks of the Litchfield Province, western Pine Creek Orogen, Northern Territory. Northern Territory Geological Survey, Record 2010-005.  **NEEDHAM RS, Stuart-Smith PG, 1984. Geology of the Pine Creek Geosyncline, Northern Territory, 1:500 000 scale map. Bureau of Mineral Resources, Australian Bureau of Mineral Resources, Canberra. ACT.  **SHEPPARD S, Tyler IM, Griffin TJ and Taylor WR, 1999. Palaeoproterozoic subduction-related and passive margin basalts in the Halls Creek Orogen, northwest Australia. Australian Journal of Earth Sciences 46, 679-690.|16-MAY-23
24634|Woolner Granite|Name source|Woolner' Homestead; grid reference GM 706329, Koolpinyah 1:100 000 sheet (5173).|16-MAY-23
24634|Woolner Granite|Type section locality|The various granite types are represented in core from the following drill holes showing cored intersection depths and grid co-ordiante locations DH P11-1 (69.75 m-70.95m) GM668384, DH P4-1 (37 m-38 m) GM628281, DH P14-1B (76.0 m-80.7 m) GM 710328 and DH P12-11 (52.22 m-53.55 m) GM 716250. These holes were drilled by Geopeko Limited. Core is stored at the Northern territory Department of Mines and Energy Core Library, Darwin.|16-MAY-23
24634|Woolner Granite|Extent|Northeastern part of the Koolpinyah 1:100 0000 sheet area and the northwestern part of the Point Stuart 1:100 0000 sheet area. The unit is non-outcropping and is overlain by 50-70 m of Mesozoic and Cainozoic sediments. The total areal extent of the granite is approximately 170 km2.|16-MAY-23
24634|Woolner Granite|Lithology|Strongly foliated red-brown granite and albitised grey biotite granite. Weakly foliated grey and pink two mica granite.|16-MAY-23
24634|Woolner Granite|Relationships and boundaries|Overlain unconformably by the Dirty Water Metamorphics, and unconformably by Koolpinyah Dolomite.|16-MAY-23
24634|Woolner Granite|Age reasons|2674 +/- 3 Ma, Glass et al 2009, Glass et al 2010, Carson et al 2010; 2675 +/- 28 Ma, Williams and Compston 1983|16-MAY-23
24634|Woolner Granite|Age reasons|An age of 2675 +/- 14 m.y. was determined using ion microprobe U-Pb age determinations on zircons (I S Williams and W Compston, 1983).|16-MAY-23
24634|Woolner Granite|Proposed publication|Koolpinyah Explanatory Notes (Northern Territory Geological Survey)|16-MAY-23
24634|Woolner Granite|Comments|More refined age discussed for Woolner Granite in: Hollis and Glass, Nov 2010 Definition Card for Njibinjibinj Gneiss|16-MAY-23
24634|Woolner Granite|References|**CARSON CJ, Hollis JA, Glass LM, Close DF, Whelan JA and Wygralak A, 2010. Summary of results. Joint NTGS-GA geochronology project: East Arunta Region, Pine Creek Orogen and Murphy Inlier, July 2007-June 2009. Northern Territory Geological Survey, Record 2010-004.    **GLASS LM, Hollis JA and Carson CJ, 2009. Geochemical and isotopic discrimination methods for Neoarchaean and Palaeoproterozoic rocks in western Arnhem Land, Pine Creek Orogen: Applications for uranium exploration: in 'Annual Geoscience Exploration Seminar (AGES) 2009. Record of abstracts'. Northern Territory Geological Survey, Record 2009-002      **GLASS LM, Hollis JA, Carson CJ, Yaxley G and Armstrong R, 2010. Archaean and Palaeoproterozoic crustal evolution processes in the Pine Creek Orogen: U-Pb, Hf, O, Nd isotopic data and geochemistry: in 'Annual Geoscience Exploration Seminar (AGES) 2010, Record of abstracts'. Northern Territory Geological Survey, Record 2010-002.     **WILLIAMS IS and Compston W, 1983. Ion microprobe U-Pb dating of zircons from granitoids recovered in core from drill holes P4/1D, P11/1, P12/11 and P14/1, Woolner, Northern Territory: in Manning ER, Richardson BR and Starkey LJ. Annual Report for EL 3478 "Woolner", Appendix 3. Mobil Energy Minerals Australia Inc. Northern Territory Department Geological Survey, Open File Company Report CR1983-0231.|16-MAY-23
24634|Woolner Granite|Unit name|Woolner granite|16-MAY-23
23268|Wundirgi Formation|Name source|After Wundirgi  1:50 000 map sheet.|16-MAY-23
23268|Wundirgi Formation|Unit history|Informal unit Ew3 and some  outcrops of unit Ew7 of former Warramunga Group  (Mendum and Tonkin 1976) in part. These rocks are now recognised as part of the Flynn Subgroup which unconformably overlies Warramunga Formation.|16-MAY-23
23268|Wundirgi Formation|Geomorphic expression|Forms recessive,  undulating  outcrops  and  upstanding mesas extending east-west across central FLYNN and in central-eastern SHORT RANGE, i.e., outcrop extends along southern flank of major upstanding ridge which constitutes Short Range.|16-MAY-23
23268|Wundirgi Formation|Type section locality|Approximately 1400 m of succession exposed in creek immediately west (lat. 19deg19'00"S, long. 134deg24'35"E; GR LU802636) of Last Hope to contact with the overlying Brumbreu Formation at lat. 19deg17'56"S, long. 134deg24'38"E (GR LU808637)(top boundary  stratotype). Reference locality: Volcanic rocks (tuff and lava) are well exposed to the west of Last Hope at lat. 19deg19'33"S, long.  134deg24'32"E (GR LU798618).|16-MAY-23
23268|Wundirgi Formation|Extent|Restricted in outcrop to FLYNN, SHORT RANGE and KELLY.|16-MAY-23
23268|Wundirgi Formation|Thickness range|Difficult to estimate due to discontinuous outcrop, folding and faulting. Probably ranges from about 600 m in east to >1.5 km in west.|16-MAY-23
23268|Wundirgi Formation|Lithology|Quartz-lithic arenite and shale. Volcanic fragments are dominant lithic clasts. Thinly-bedded/laminated tuff is a minor component, and there is an intermediate volcanic (andesitic) component, although in weathered outcrop this is extremely difficult to distinguish from intrusive diorite. Monotonous succession of medium- to thick-bedded, interbedded sandstone and shale becoming thin- to medium-bedded and very planar-bedded upwards. Well rippled sandstone becomes much more  abundant than shale towards top of unit, resulting in transitional relationship with sandstone-dominated Brumbreu Formation,  although contact is quite sharp with a distinctive grey-green lithic sandstone marking the onset of Brumbreu Formation.|16-MAY-23
23268|Wundirgi Formation|Depositional environment|Predominantly subaqueous with a minor subaerial volcanic component.|16-MAY-23
23268|Wundirgi Formation|Relationships and boundaries|Conformably  overlies  Warrego  Volcanics. Conformably underlies Brumbreu Formation. Probably laterally equivalent, in part, to the Bernborough Formation. Intruded by diorite and dolerite, particularly towards top, and minor lamprophyre. The Wundirgi Formation is part of the Flynn Subgroup of the Churchills Head Group which unconformably overlies Warramunga Formation. Top boundary stratotype: Transitional contact with overlying Brumbreu Formation at lat. 19deg17'56"S, long. 134deg24'38"E (GR LU808637). Bottom boundary stratotype: Basal contact with Warrego Volcanics at lat. 19deg25'31"S, long. 134deg25'43"E (GR LU998530) on FLYNN where thick-bedded quartz-lithic sandstone and shale of Wundirgi Formation overlie pale green silicified tuff of Warrego Volcanics. Approximately 500 m of the lower Wundirgi Formation sedimentary rocks are well exposed in a northnorthwest direction from this point.|16-MAY-23
23268|Wundirgi Formation|Age reasons|Palaeoproterozoic. At least in part equivalent to Bernborough Formation  which  has been dated using ion microprobe by U-Pb on zircons at 1833+/-4 Ma (Compston 1991) and revised to 1840+/-8 Ma and 1845+/-4 Ma by Compston (1994).|16-MAY-23
23268|Wundirgi Formation|Correlations|As a constituent formation of the Flynn Subgroup it correlates with part of the Ooradidgee Subgroup of the Hatches Creek Group in the Davenport province, in particular Rooneys Formation.|16-MAY-23
23268|Wundirgi Formation|Defn author|Donnellan, N. 1995.|16-MAY-23
29229|Wuraliwuntya Member|Name source|Wuraliwuntya Creek, mount Young 1:250 000 scale map sheet area.|16-MAY-23
29229|Wuraliwuntya Member|Unit history|Originally mapped as part of the now-abandoned 'Masterton Formation' by Plumb and Paine (1964). The Wununmantyala Sandstone was named by Jackson and others (1987) but the unit described herein was not identified.|16-MAY-23
29229|Wuraliwuntya Member|Geomorphic expression|Recessive; forms strike-valleys with poor outcrop.|16-MAY-23
29229|Wuraliwuntya Member|Type section locality|7 km east of Lorella Homestead at latitude 15o43.6'S, longitude 135o42.3'E. Base at AMG grid reference NC754613; top at NC755611.|16-MAY-23
29229|Wuraliwuntya Member|Extent|Mainly restricted to the southern part of the Mount Young 1:250 000 map sheet area (northern parts of the Tawallah and Scrutton Ranges). May be present near northern edge of Bauhinia Downs 1:250 000 map sheet area.|16-MAY-23
29229|Wuraliwuntya Member|Thickness range|57 m measured at type section. Thickens to the east to an estimated maximum of 200-300 m along the eastern flank of Tawallah Range.|16-MAY-23
29229|Wuraliwuntya Member|Lithology|Greenish to brown-yellow and reddish, very thin- to medium-bedded, flaggy, fine- to medium-grained, micaceous sandstones interbedded with mudstone. Forms a roughly thickening-upward and coarsening-upward sequence with mainly mudstone at the base. Sandstones are sharp-based with sole marks, and bed tops are often wave-rippled. Glauconite abundant in some beds. Rare halite pseudomorphs.|16-MAY-23
29229|Wuraliwuntya Member|Depositional environment|Shallowing-upward, storm-dominated marine environment. Significantly deeper depositional environment than lower part of Wununmantyala Sandstone.|16-MAY-23
29229|Wuraliwuntya Member|Relationships and boundaries|Member of the Wununmantyala Sandstone, Tawallah Group, McArthur Basin. Conformably overlies lower part of Wununmantyala Sandstone. Conformably overlain by Settlement Creek Volcanics or unconformably by Masterton Sandstone of the McArthur Group. Probably related to the rest of the Wununmantyala Sandstone by a deepening-related facies change. Lower boundary picked at change from prominent medium-grained red sandstones to recessive mudstones and fine-grained sandstones. Top picked at incoming of volcanic rocks (Settlement Creek Volcanics) or erosive contact with prominent conglomerate or white sandstone of Masterton Sandstone.|16-MAY-23
29229|Wuraliwuntya Member|Age reasons|Can be bracketed radiometrically between 1851 +/- 7 Ma (Scrutton Volcanics) and 1713 +/- 6 Ma (Tanumbirini Rhyolite).|16-MAY-23
29229|Wuraliwuntya Member|Category|2|16-MAY-23
29229|Wuraliwuntya Member|Proposer|Haines P.W., Pietsch B.A., Rawlings D.J., Madigan T.|16-MAY-23
80428|Wyworrie Member|Name source|After Wyworrie Station (MGA94 53K251000mE 295000mN; latitude -15.411' longitude 132.685') in Southwestern Elsey 1:100k mapsheet in northern-central Larrimah 1:250k mapsheet.|16-MAY-23
80428|Wyworrie Member|Unit history|Equivalent to informal 'Upper' Velkerri Formation of Lanigan et al (1994) and upper Velkerri Formation of subsequent usage. Its parent units are the Velkerri Formation of the Roper Group.|16-MAY-23
80428|Wyworrie Member|Geomorphic expression|Not differentiated from parent Velkerri Formation in outcrop due to poor exposure. Velkerri Formation is recessive and exposures are generally restricted to rare small outcrops of buff- to white-weathering laminated siltstone and mudstone or fragments of this lithology in skeletal soil. The formation is present in scarp slopes beneath the overlying Moroak Sandstone and also underlies extensive plains.|16-MAY-23
80428|Wyworrie Member|Type section locality|Wyworrie Member is not recognised at surface due to poor exposure, and a complete intersection of the member in drillhole Pacific Oil and Gas Ltd (POG) Alexander-1 (Barberis and Ledlie 1988) from ca 280m depth (base) to ca 62m (top) is therefore nominated. Velkerri Formation is 555m thick in Alexander-1 (617-62m depth). Alexander -1 is located at MGA9453K 484523 mE 8322964mN; latitude -15.16911degrees,  longitude 134.855921degrees. Core is housed in the NTGS Core Facilities in Darwin.|16-MAY-23
80428|Wyworrie Member|Extent|Subsurface intersections in drillholes located in Urapunga, Larrimah, Hodgson Downs, Tanumbirini and Bauhinia Downs 1:250k mapsheets, northeeastern Northern Territory. Not differentiated from parent formation in outcrop due to poor exposure.|16-MAY-23
80428|Wyworrie Member|General description|Alternating, interbedded and interlaminated grey-green mudstone and pale grey siltstone, with lesser, commonly glauconitic and sometimes micaceous, light grey fine-grained sandstone that increases in proportion towards the top. Wyworrie Member has a relatively higher proportion of siltstone and sandstone relative to claystone, in comparison to finer-grained underlying Amunggee Member, and lacks distinctive mudrock organofacies intervals of Amungee Member. In hyperspectral data (HyLogger), basal contact is marked by an increase in abundance of quartz from Amungee Member, a weathered quartzo-feldspathic mineralogy throughout and a further increase in abundance of quartz at base of Moroak Sandstone.|16-MAY-23
80428|Wyworrie Member|Thickness range|218m thick. Complete intersections range from a minimum of 88.5m in BMR Urapunga-4 to a maximum of 705m in Santos Tanumbirini-1. Other significant intersections include 410m in Origin Amungee NW-1; 285.97 Pangaea Birdum Creek-1; 218.5 m in Origin Kalala S-1; 180.9m in POG Lady Penrhyn-2; 460.8m in POG McManus-1; 250.9 m in Falcon Shenandoah-1A; 207.3m in Pangaea Tarlee S-3; and 178.35m in Pangaea Wyworrie-1.|16-MAY-23
80428|Wyworrie Member|Lithology|Alternating interbedded and interlaminated grey-green mudstone and pale grey siltstone, with lesser commonly glauconitic and sometimes micaceous, light grey fine-grained sandstone that increases in proportion towards the top.|16-MAY-23
80428|Wyworrie Member|Depositional environment|Subtidal, sub-wave base, and generally quiet marine with regular current activity, consistent with periodic turbidity currents (Munson 2016 and references therein).|16-MAY-23
80428|Wyworrie Member|Relationships and boundaries|Conformable lower boundary with underlying Amungee Member is gradational over several metres within mudrocks as organic content wanes upward; contact is not clearly defined by lithology and is best picked using a combination of wireline and chemostratigraphic logs (see Geophysical Expression and Geochemistry below). Conformable and gradational upper contact with overlying Moroak Sandstone (see comments).|16-MAY-23
80428|Wyworrie Member|Identifying features|Wyworrie Member has a relatively higher proportion of siltstone and sandstone relative to claystone, in comparison to finer-grained Amungee Member, and lacks distinctive mudrock organofacies intervals of Amungee Member.|16-MAY-23
80428|Wyworrie Member|Structure and Metamorphism|Unmetamorphosed. Flat-lying, or gentle to open folds, and/or brittle faults with minor displacements in most areas. More intense deformation (thrusts, shears, close to tight folds) in vicinity of major fault zones.|16-MAY-23
80428|Wyworrie Member|Age reasons|Mesoproterozoic. Maximum deposition age constrained by SHRIMP U-Pb zircon ages of 1492 +/- 4 Ma and 1493 +/- 4 Ma from rare tuffs in Showell Member of underlying Mainoru Formation (Jackson et al 1999), and by TIMS U-Pb baddeleyite age of 1312.9 +/- 0.7 Ma age for Derim Derim Dolerite, which intrudes Velkerri Formation. (Collins et al 2018). Organic-rich shales from underlying Amungee Member have been dated by Re-Os method at 1417 +/- 29 Ma and 1361 +/- 21 Ma (Creaser and Kendall 2007, Kendall et al 2009).|16-MAY-23
80428|Wyworrie Member|Correlations|No known correlatives at member level. Parent Velkerri Formation is probably equivalent to Lake Woods beds or Renner Group of Tomkinson Province (Hussey et al, 2001), Tijunna Group (in part) of Birrindudu Basin; and Mullera Formation (in part) of South Nicholson Basin (Munson 2016).|16-MAY-23
80428|Wyworrie Member|Alteration and Mineralisation|Some in situ weathering of minerals, including alteration of labile minerals to clays. Organic-rich intervals in lower part have some source rock potential and are prospective for unconventional petroleum.|16-MAY-23
80428|Wyworrie Member|Geophysical Expression|Gamma and resistivity logs both show a marked upward-decline in values from top of Amungee Member, but remain elevated through Wyworrie Member, particularly in comparison to Kalala Member. Resistivity logs have a distinctive, relatively low flat character.|16-MAY-23
80428|Wyworrie Member|Geochemistry|TOC of mudrocks is appreciably lower than in Amungee Member, but slightly higher than in Kalala Member; organic-rich mudrock intervals are absent. Phosphate, carbonate, and redox-sensitive trace elements (eg, U, Ni, V, Mo, Zn, Cu, Tl) all have typically low values compared to Amungee Member, and are higher towards the base. Log values for some oxides and heavy mineral trace elements (eg, Al2O3, K2O, Sc, Nb, Th, Sn, Cr) are elevated relative to Amungee Member.|16-MAY-23
80428|Wyworrie Member|Defn author|TJ Munson and D Revie, April 2018.|16-MAY-23
80428|Wyworrie Member|Proposed publication|Munson TJ and Revie D, 2018. Stratigraphic subdivision of Velkerri Formation, Roper Group, McArthur Basin, Northern Territory. Northern Territory Geological Survey, Record 2018-006.|16-MAY-23
80428|Wyworrie Member|Comments|Conformable upper contact with Moroak Sandstone is sharp and erosive in some wells (eg BMR Urapunga-4; Abbott and Sweet 2001) and gradational in other wells (eg type section in Alexander-1; Barberis and Ledlie 1988). A number of palynomorph taxa have been recovered from Wyworrie Member in drillholes POG Altree-2 and POG McManus-1 (Grey (2015). Most palynomorphs could not be readily assigned to existing species or precisely dated; the identified taxa tend to be long-ranging and can also occur in underlying and overlying units. Palynomoprhs were generally interpreted by Grey (2015) to be indicative of shallow-water nearshore deposition.|16-MAY-23
80428|Wyworrie Member|References|Abbott ST and Sweet IP, 2001. Measured sections and drillcore logs from the Urapunga and Roper River 1:250 000 mapsheets, Northern Territory. Northern Territory Geological Survey, Technical Report 2001 004. **Barberis C and Ledlie I, 1988. Alexander No 1, EP 4, McArthur Basin, NT. Well completion report. Pacific Oil & Gas Ltd. Northern Territory Geological Survey, Open File Petroleum Report PR1989-0007. **Collins A, Farkas J, Glorie S, Cox G, Blades ML, Yang Bo, Nixon A, Bullen M, Foden JD, Dosseto A, Payne JL, Denyszyn S, Edgoose CJ, Close D, Munson TJ, Menpes S, Spagnuolo S, Gusterhuber J, Sheridan M, Baruch-Jurado E and Close D, 2018. Orogens to oil: government-industry-academia collaboration to better understand the greater McArthur Basin: in Annual Geoscience Exploration Seminar (AGES) Proceedings, Alice Springs, Northern Territory, 20-21 March 2018. Northern Territory Geological Survey, Darwin. 49-51. **Creaser RA and Kendall B, 2007. Re-Os geochronology of organic-rich shales; Placing absolute time pins in ancient sedimentary basins. American Geophysical Union, Fall Meeting 2007, abstract #V31G-01. **Grey K, 2015. Mesoproterozoic biostratigraphic correlation in the Beetaloo Sub-basin, Northern Territory, Australia and potential for correlation with other northern Australian basins: in 'Annual Geoscience Exploration Seminar (AGES) 2015. Record of Abstracts.' Northern Territory Geological Survey, Record 2015-002. **Jackson MJ, Sweet IP, Page RW and Bradshaw BE, 1999. The South Nicholson and Roper Groups: Evidence for the early Mesoproterozoic Roper Superbasin: in Bradshaw BE and Scott DL (editors). 'Integrated basin analysis of the Isa Superbasin using seismic, well-log and geopotential data: an evaluation of the economic potential of the northern Lawn Hill Platform.' Australian Geological Survey Organisation Record 1999/19 (CD ROM), 36-45. **Kendall B, Creaser RA, Gordon GW and Anbar AD, 2009. Re¿Os and Mo isotope systematics of black shales from the Middle Proterozoic Velkerri and Wollogorang Formations, McArthur Basin, northern Australia. Geochimica et Cosmochimica Acta 73, 2534-2558. **Lanigan K, Hibbird S, Menpes S and Torkington J, 1994. Petroleum exploration in the Proterozoic Beetaloo Sub basin, Northern Territory. APEA Journal 34, 674-691. **Munson TJ, 2016. Sedimentary characterisation of the Wilton package, greater McArthur Basin, Northern Territory. Northern Territory Geological Survey, Record 2016-003.|16-MAY-23
80335|Xanten Granodiorite|Name source|Xanten copper prospect (abandoned; 611905 mE 7491646 mN) in Jervois Range 1:100 000 mapsheet, Northern Territory.|16-MAY-23
80335|Xanten Granodiorite|Unit history|Xanten Granite of Shaw et al (1985).|16-MAY-23
80335|Xanten Granodiorite|Geomorphic expression|Low, blocky hills devoid of vegetation.|16-MAY-23
80335|Xanten Granodiorite|Type section locality|622232mE 7487484mN (GDA94, Zone53) in Jervois Range 1:100 000 mapsheet, Northern Territory; access via private tracks.|16-MAY-23
80335|Xanten Granodiorite|Extent|Small occurrence covering about 3x5 km at the southern limit of the Jervois Range in central Jervois Range 1:100 000 mapsheet.|16-MAY-23
80335|Xanten Granodiorite|General description|Granodiorite to tonalite: fine to medium-grained, equigranular, leucocratic comprising quartz-plagioclase with minor K-feldspar, rare biotite and muscovite; strongly weathered and altered (silicified); moderately foliated, locally gneissic with alternating 1-5 mm thick and laterally discontinuous plagioclase- and quartz-rich bands and about 3 vol% biotite altered to chlorite.|16-MAY-23
80335|Xanten Granodiorite|Lithology|Leucocratic granodiorite, inequigranular, medium-grained plagioclase (1-3 mm across) in a groundmass of fine-grained recrystallised quartz and K-feldspar, accessory titanite, epidote and opaque oxides.|16-MAY-23
80335|Xanten Granodiorite|Depositional environment|Continental margin environment, either arc cordillera, back arc basin, or derived from melting of pre-existing crust that formed in a continental margin environment.|16-MAY-23
80335|Xanten Granodiorite|Relationships and boundaries|No boundaries exposed; interpreted to intrude Bonya Metamorphics (contacts not exposed); intruded by quartz veins and quartz-vein breccias; interpreted to have a faulted, and in parts, unconformable contact with Grant Bluff Formation and Elkera Formation of the Georgina Basin.|16-MAY-23
80335|Xanten Granodiorite|Identifying features|Leucocratic granodiorite lacking mafic enclaves (compared to adjacent Jervois Granodiorite).|16-MAY-23
80335|Xanten Granodiorite|Structure and Metamorphism|Commonly inequigranular and recrystallised; locally gneissic and sheared; intruded prior to regional amphibolite facies high-thermal-gradient metamorphism.|16-MAY-23
80335|Xanten Granodiorite|Age reasons|Magmatic crystallisation at 1777 +/- 8 Ma (LA-ICP-MS 207Pb/206Pb; Beyer et al 2018).|16-MAY-23
80335|Xanten Granodiorite|Correlations|Interpreted to be co-magmatic and co-genetic with constituent units of the Casper Suite based on similar geochemical and isotopic composition, and timing of structural fabric development.|16-MAY-23
80335|Xanten Granodiorite|Alteration and Mineralisation|Varying degrees of sericitisation and secondary muscovite; locally quartz-K-feldspar altered; commonly quartz rich and silicified.|16-MAY-23
80335|Xanten Granodiorite|Geophysical Expression|Irregular magnetic low signal.|16-MAY-23
80335|Xanten Granodiorite|Geochemistry|Granodiorite and tonalite, strongly peraluminous. Moderately-sloping LREE, flat HREE, and pronounced negative Eu anomalies.|16-MAY-23
80335|Xanten Granodiorite|Defn author|Anett Weisheit, Barry Reno, Eloise Beyer (Northern Territory Geological Survey), 02-JUL-2018.|16-MAY-23
80335|Xanten Granodiorite|Proposed publication|Weisheit A, Reno BL and Beyer EE, in review. Jervois Range Special, Northern Territory. 1:100 000 geological map explanatory notes, 6152 and part 6252. Northern Territory Geological Survey, Darwin.|16-MAY-23
80335|Xanten Granodiorite|References|Beyer EE, Reno BL, Weisheit A, Whelan JA, Thompson JM, Meffre S and Woodhead JD, 2018. Summary of results. NTGS laser ablation ICP-MS U-Pb-Hf geochronology project: selected samples from JERVOIS RANGE 1:100 000 and TOBERMOREY 1:250 000 mapsheets, Aileron and Irindina provinces, January 2014 - December 2016. Northern Territory Geological Survey, Record 2018-001.   **Shaw, R.D., Warren, R.G., Freeman, M.J., 1985, Statigraphic definitions of named units in the Arunta Block, Northern Territory, 1979-82. Bureau of Mineral Resources, Australia, Report, 260.|16-MAY-23
24590|Yaddanilla Sandstone|Name source|Yaddanilla Creek in the west of Hanlon 1:100 0000 Sheet area, Frew River 1:250 000 Sheet area.|16-MAY-23
24590|Yaddanilla Sandstone|Type section locality|About 4 km NW of Vaddingilla Rockhole (latitude 20o49'00"S, longitude 135o39'10"E): from GR 653024, where the formation conformably overlies Vaddingilla Formation, NE to GR 661029, the limit of bedrock outcrop - bedrock to E is concealed beneath Quaternary surficial cover. In this section the Yaddanilla Sandstone, dipping 20o-45o NE, forms a sequence of strike ridges of which the highest is the westernmost.|16-MAY-23
24590|Yaddanilla Sandstone|Extent|Confined to the western part of Hanlon 1:100 0000 Sheet area.|16-MAY-23
24590|Yaddanilla Sandstone|Thickness range|About 300 m in type section.|16-MAY-23
24590|Yaddanilla Sandstone|Lithology|Ridge-forming quartz arenite and feldspathic quartz arenite; some interbanded recessive rocks (concealed).|16-MAY-23
24590|Yaddanilla Sandstone|Relationships and boundaries|Conformable on Vaddingilla Formation; no overlying units exposed.|16-MAY-23
24590|Yaddanilla Sandstone|Age reasons|Younger than 1870 m.y. - U-Pb zircon age for volcanics in the Warramunga Group unconformably underlying the Hatcheas Creek Group. Older than 1640 m.y. - Rb-Sr whole-rock age for granite intruding the Hatches Creek Group.|16-MAY-23
24590|Yaddanilla Sandstone|Comments|Remarks: Ridge-forming formation t top of the Hanlon Subgroup. Youngest formation of the Hatches Creek Group exposed in the Davenport Province.|16-MAY-23
24590|Yaddanilla Sandstone|Defn Reference|86/25362|16-MAY-23
24590|Yaddanilla Sandstone|Proposer|Wyche S.|16-MAY-23
24590|Yaddanilla Sandstone|Resdate|07-OCT-1981|16-MAY-23
24592|Yakalibadgi Microgranite|Name source|Yakalibadgi Hill (251700E, 7554000N), 1.5 km SW of Blockhill Bore, NW part of Reynolds Range 1:100 000 Sheet area.|16-MAY-23
24592|Yakalibadgi Microgranite|Type section locality|Point GR 5453-660366, 8 km NW of Mount Thomas, Reynolds Range 1:100 0000 Sheet area (sample point C726B on Prelim. Geol. Map). Good exposure of foliated dark grey microgranodiorite with small biotite-rich xenoliths.|16-MAY-23
24592|Yakalibadgi Microgranite|Extent|SW side of NW part of Reynolds Range, from vicinity of Mt Thomas NW-wards; may extend NW into adjoining Denison 1:100 000 sheet.|16-MAY-23
24592|Yakalibadgi Microgranite|Lithology|Porphyritic microgranite somewhat retrogressively metamorphosed, consisting of feldspar (sericitized), quartz, biotite, muscovite, zircon, tourmaline, apatite + opaque mineral. Phenocrysts consist of quartz and sericitized plagioclase. Microcline only in groundmass. Grades SE into medium-grained (near Mount Thomas) at SE end of body, and to NW into biotite schist and biotite-muscovite schist as retrogression and deformation obliterate original texture - original phenocrysts survive as quartz and plagioclase. augen. Bulk chemical analyses of 3 samples indicate granodiorite composition.|16-MAY-23
24592|Yakalibadgi Microgranite|Relationships and boundaries|Intrudes Lander Rock beds. Adjoins base of basal conglomerate of Mount Thomas Quartzite with apparent concordance, but is regarded as intrusive into Mount Thomas Quartzite because at several other places the base of Mt Thomas Quartzite has acted as a barrier to granitic intrusions but which are known to breach the barrier in a few localities.|16-MAY-23
24592|Yakalibadgi Microgranite|Identifying features|Reason for Proposed Name: A distinctive and easily mapped fine-grained granitic body.|16-MAY-23
24592|Yakalibadgi Microgranite|Age reasons|Younger than Lander Rock beds (Early Proterozoic or older), almost certainly younger than Mount Thomas Quartzite (which unconformably overlies Lander Rock beds), older than regional metamorphism of Mount Thomas Quartzite, which was subsequently intruded by Napperby Gneiss (dated at 1800-1500 m.y. by Rb-Sr muscovite and whole rock (and Mount Airy Orthogneiss (undated). Hence, late Early Proterozoic or early Middle Proterozoic (Early Carpentarian). K-Ar date of 920 m.y. on biotite from SE part of body probably partly reset by Alice Springs Orogeny (Carboniferous).|16-MAY-23
24592|Yakalibadgi Microgranite|Proposed publication|1. 'Geology of NW Arunta Block' - BMR Publication.  2. 'Stratigraphic definitions in Arunta Block' - BMR Microfiche Report.|16-MAY-23
24592|Yakalibadgi Microgranite|Defn Reference|80/20787|16-MAY-23
24592|Yakalibadgi Microgranite|Reserved? Yes/No|Yes, as Yakalibadgi Granite|16-MAY-23
82949|Yam Gneiss|Name source|Yam Creek Bore in JINKA 1:100 000 mapsheet, Northern Territory (135.5471degreesE 22.7037degreesS (GDA 2020)).|16-MAY-23
82949|Yam Gneiss|Geomorphic expression|Scattered low hills and rubbly outcrop.|16-MAY-23
82949|Yam Gneiss|Type section locality|About 2 km east-northeast of Molyhil W-Mo deposit at 135.7668degreesE 22.7556degreesS (GDA2020) in JINKA. Access via public roads and private tracks. Some off-track driving/walking might be required.|01-JUN-23
82949|Yam Gneiss|Description at type locality|Low hills of strongly weathered, friable and disaggregated gneiss characterised by an inequigranular assemblage of fine- to very fine-grained quartz-K-feldspar-plagioclase-biotite. Feldspars are leached and sericitised, and biotite is altered to clay minerals. Biotite varies between fine- to medium-grained and comprises about 10 vol% of the mineral mode.|16-MAY-23
82949|Yam Gneiss|Extent|Central JINKA 1:100 000 mapsheet between Yam Creek and Elua Range.|16-MAY-23
82949|Yam Gneiss|General description|Commonly intensely weathered biotite-bearing quartzofeldspathic gneisses of indeterminate protolith. Gneissic foliation is moderately to well developed, including compositional layering of quartz-rich and plagioclase-rich bands; locally mylonitic with reduced biotite-content. Geochemical compositions are granodiorite and rare monzogranite.|16-MAY-23
82949|Yam Gneiss|Thickness range|Unknown.|16-MAY-23
82949|Yam Gneiss|Lithology|Strongly weathered, friable and disaggregated gneiss characterised by an inequigranular assemblage of fine- to very fine-grained quartz-K-feldspar-plagioclase-biotite. Feldspars are leached and sericitised, and biotite is altered to clay minerals. Biotite varies between fine- to medium-grained and comprises about 10 vol% of the mineral mode.|16-MAY-23
82949|Yam Gneiss|Depositional environment|Genesis: Precursor rocks cannot be determined. Possibly I-type igneous rocks with minor metasedimentary rocks. Based on regional geology, these rocks possibly formed in a back-arc basin.|16-MAY-23
82949|Yam Gneiss|Relationships and boundaries|Is inferred to include xenoliths of Deep Bore Metamorphics and is intruded by Marshall Granite.|16-MAY-23
82949|Yam Gneiss|Identifying features|Intensely weathered, fine- to very fine grained, locally compositionally layered. Granodioritic compositions (compared with granitic compositions of rocks of the surrounding Molyhil Suite, Baikal Supersuite).|16-MAY-23
82949|Yam Gneiss|Structure and Metamorphism|Common moderate- to well-developed gneissic foliation; mylonitic in Delny Shear Zone. Intruded prior to regional granulite- to amphibolite-facies high-thermal-gradient metamorphism.|16-MAY-23
82949|Yam Gneiss|Age reasons|A SHRIMP 207Pb/206Pb zircon age of 1797 +/- 7 Ma is interpreted to record timing of magmatic crystallisation (Kositcin et al 2021).|16-MAY-23
82949|Yam Gneiss|Correlations|Protoliths to the meta-igneous components possibly formed contemporaneously with the Baikal Supersuite; protoliths of the speculative metasedimentary components possibly relate to the Deep Bore Metamorphics.|16-MAY-23
82949|Yam Gneiss|Alteration and Mineralisation|Strongly altered (sericitised, clay mineral-alteration). Possibly host to some of the W-Mo mineralisation at the Molyhil deposit (McGloin and Weisheit 2021).|16-MAY-23
82949|Yam Gneiss|Geophysical Expression|Commonly associated with magnetic low responses; no characteristic gravity response; radiometric high response.|16-MAY-23
82949|Yam Gneiss|Geochemistry|Weakly peraluminous I-type granodiorite and rare monzogranite. Moderate to strong LREE enrichment compared to MREE, and moderately to strongly negative Eu anomalies.|16-MAY-23
82949|Yam Gneiss|Defn author|Barry Reno, Eloise Beyer, Anett Weisheit, Pablo Farias (NT Department of Industry, Tourism and Trade, Northern Territory Geological Survey) 3-MAY-2022.|16-MAY-23
82949|Yam Gneiss|References|Kositcin N, Magee CW, Whelan JA and Champion DC, 2011. New SHRIMP geochronology from the Arunta Region: 2009-2010. Geoscience Australia, Record 2011-014.  **McGloin MV and Weisheit A, 2021. Epigenetic copper and tungsten mineralisation in JINKA and JERVOIS RANGE, northeastern Aileron Province. Northern Territory Geological Survey, Record.|16-MAY-23
79100|Yambla Gneiss|Name source|After Yambla Creek in western ILLOGWA CREEK 1:250 000 mapsheet area, 135.0977degreesE 23.2481degreesS (GDA2020)|16-MAY-23
79100|Yambla Gneiss|Unit history|The Yambla Gneiss comprises the lowest part of the former 'Irindina Gneiss' succession of Joklik (1955). The former 'Irindina Gneiss' has been subdivided into two formal units, Yambla and Spriggs gneisses, both formations of the Harts Range Metamorphic Complex. Yambla Gneiss was informally termed the 'lower Irindina Gneiss' by Maidment (2005) and Maidment et al (2013).|16-MAY-23
79100|Yambla Gneiss|Geomorphic expression|Unit forms undulating terrain with a moderate relief of low hills and rises, or up to km-long strike ridges. Outcrops tend to be moderately to strongly weathered.|16-MAY-23
79100|Yambla Gneiss|Type section locality|Type locality is at the base of the Yambla Gneiss, 650 m SE of where a track crosses the Spriggs Creek; 135.0827degreesE 23.1078degreesS (GDA2020). A traverse to 135.0769degreesE 23.111degreesS (GDA2020) will cross all of the Yambla Gneiss strata present in this area.|16-MAY-23
79100|Yambla Gneiss|Description at type locality|Gneiss, garnet-biotite-K-feldspar-plagioclase-quartz bearing metagreywacke and metamudstone. Locally contains sillimanite; locally migmatitic. Garnet is glassy and typically fuschia, pink, or red.|16-MAY-23
79100|Yambla Gneiss|Extent|The unit is regionally extensive, and found throughout the Irindina Province in southern ALCOOTA and HUCKITTA and northern ILLOGWA CREEK and ALICE SPRINGS.|16-MAY-23
79100|Yambla Gneiss|General description|The Yambla Gneiss comprises dominantly metagreywacke paragneiss with lesser mica-bearing metasandstone, calc-silicate rock, and marble interlayered at the m- to dm-scale. The unit is variably metamorphosed, with the highest metamorphic grade observed as migmatitic metagreywacke gneiss in the Harts Range in ALCOOTA and ILLOGWA CREEK. In HUCKITTA, the Yambla Gneiss is not migmatitic. Where present, garnet is commonly distinctively fuchsia-coloured and can be gem quality, which is a distinctive feature compared to other units in the area. Sillimanite is rare, and commonly occurs as fibrolite.|16-MAY-23
79100|Yambla Gneiss|Thickness range|This unit may be partially duplicated or attenuated by structural deformation. The exposed section of Yambla Gneiss at this location has a thickness of approximately 400 m. The thickness of original sedimentary units, their stratigraphic order, and an absolute younging direction cannot be determined because of structural and metamorphic overprinting. The unit is possibly widespread in the subsurface; however, structural repetition is likely.|16-MAY-23
79100|Yambla Gneiss|Lithology|Gneiss, garnet-biotite-K-feldspar-plagioclase-quartz bearing metagreywacke and metamudstone. Locally contains sillimanite; locally migmatitic. Garnet is glassy and typically fuschia, pink, or red. Along the traverse at the type locality, a conformable layer of diopside-grossular-calcite+/-wollastonite-bearing marble is interlayered with the gneiss (eg 135.0791degreesE 23.1099degreesS (GDA2020)). Metagreywacke, metamudstone and marble are frequently interlayered with quartzite and calc-silicate rock. Quartzite is generally pure, but locally contains muscovite and opaque oxide. Calc-silicate rock is fine-grained and consists of diopside, garnet, epidote, quartz and locally hornblende.|16-MAY-23
79100|Yambla Gneiss|Depositional environment|Genesis: Unit is predominantly a metagreywacke with lesser amounts of metasandstone. The presence of rare marble and calc-silicate rock may indicate that the Yambla Gneiss was deposited in a restricted basin of a nearshore marine depositional system contemporaneous with deposition of marine-dominated units in the Georgina and Amadeus basins.|16-MAY-23
79100|Yambla Gneiss|Relationships and boundaries|In western ILLOGWA CREEK, Yambla Gneiss has a structurally transposed lower contact with Riddock Metadolerite and a structurally transposed upper contact with Leprechaun Gneiss. In southern HUCKITTA, Yambla Gneiss is structurally transposed with Eurobra Gneiss. It is intruded by Riddock Metadolerite and pegmatites, and possibly intruded by Ghost Gum Granite. The unit is unconformably overlain by Cenozoic Waite Formation equivalent.|16-MAY-23
79100|Yambla Gneiss|Identifying features|Garnet in the Yambla Gneiss is commonly distinctively fuchsia-coloured, glassy, and can be gem quality, which is a distinctive feature compared to other units in the area. Yambla Gneiss is distinguished from the Spriggs Gneiss on the basis of containing a high proportion of marble and calc-silicate rocks. Both are absent in the Spriggs Gneiss. Yambla Gneiss is distinguished from the Eurobra Gneiss on the basis of absent migmatitisation, and distinct magnetic and detrital zircon characteristics.|16-MAY-23
79100|Yambla Gneiss|Structure and Metamorphism|Penetrative gneissosity, locally schistose defined by alternating biotite-rich and feldspar-rich bands. Gneissosity is isoclinally folded on the cm?m-scale, resulting in repetition of the original succession. Metamorphic grade ranges from amphibolite facies in HUCKITTA and ALCOOTA to granulite facies in ILLOGWA CREEK with local migmatite development.|16-MAY-23
79100|Yambla Gneiss|Age reasons|U-Pb zircon data commonly have unimodal detrital age spectra with individual zircon ages spanning ca 1.80-1.60 Ga, and maximum depositional ages ranging between ca 1.73 Ga and 1.68 Ga (Buick et al 2005, Maidment 2005, Maidment et al 2013, Beyer et al 2013, Bodorkos et al 2013, Beyer et al 2018). The maximum depositional age of the Yambla Gneiss is inferred to be Tonian based on the ages of the underlying units (eg Buick et al 2005; Maidment et al 2013). The Yambla Gneiss was intruded by the Indiana Igneous Complex at 519 +/- 9 Ma (Beyer et al 2013; 238U/206Pb LA-ICP-MS; see also Maidment 2005). The combined chronologic data suggests that deposition of the sedimentary precursor to the Yambla Gneiss occurred during the Tonian-Terreneuvian.|16-MAY-23
79100|Yambla Gneiss|Correlations|Although no specific unit has been correlated with the Yambla Gneiss, its deposition is thought to coincide with Neoproterozoic to Cambrian parts of the Georgina and Amadeus basins of the Centralian A Superbasin (Maidment 2005, Maidment et al 2013).|16-MAY-23
79100|Yambla Gneiss|Alteration and Mineralisation|The unit is weakly to moderately weathered at surface. Uranium mineralisation occurs at the Yambla prospect (Drake-Brockman et al 1996). Uranium is associated with a series of structures which cross-cut the Yambla Gneiss and adjacent Spriggs Gneiss, Riddock Metagabbro and Leprechaun Gneiss. Gold, tungsten and copper mineralisation occurs at the Tibbs Prospect, which is hosted by the marble of the Yambla Gneiss (Mithril Resources Ltd 2010). Yambla Gneiss is host to pegmatites of the abandoned Plenty River Mica field and quartz veins associated with epigenetic Au and Cu mineralisation at Bruce?s in southern HUCKITTA.|16-MAY-23
79100|Yambla Gneiss|Geophysical Expression|Irregular magnetic expression with characteristic high-amplitude, short-wavelength signature over an area dominated by flat, low responses. Radiometric surveys show that the unit is relatively high in thorium and locally potassium. There is no characteristic gravity response.|16-MAY-23
79100|Yambla Gneiss|Defn author|Jo Whelan, Lachlan Hallett, Barry Reno, Anett Weisheit, Eloise Beyer, Pablo Farias (NT Department of Industry, Tourism and Trade, Northern Territory Geological Survey) 3-MAY-2022.|16-MAY-23
79100|Yambla Gneiss|References|Beyer EE, Hollis JA, Whelan JA, Glass LM, Donnellan N, Yaxley G, Armstrong R, Allen C and S Schersten A, 2013. Summary of results. NTGS lasecr ablation ICPMS and SHRIMP U-Pb, Hf and O geochronology project: Pine Creek Orogen, Arunta Region, Georgina Basin and McArthur Basin, July 2008-May 2011. Northern Territory Geological Survey, Record 2012-007.  **Beyer EE, Reno BL, Weisheit A, Whelan JA, Thompson JM, Meffre S and Woodhead JD, 2018. Summary of results. NTGS laser ablation ICP-MS U-Pb-Hf geochronology project: selected samples from JERVOIS RANGE 1:100 000 and TOBERMOREY 1:250 000 mapsheets, Aileron and Irindina provinces, January 2014-December 2016. Northern Territory Geological Survey, Record 2018-001.   **Bodorkos S, Beyer EE, Edgoose CJ, Whelan JA, Webb G, Vandenberg LC and Hallett L, 2013. Summary of results. Joint NTGS-GA geochronology project: Central and eastern Arunta Region, January 2008-June 2011. Northern Territory Geological Survey, Record 2013-003.  **Buick IS, Hand M, Williams IS, Mawby J, Miller JA and Nicol RS, 2005. Detrital zircon provenance constraints on the evolution of the Harts Range Metamorphic Complex (central Australia): links to the Centralian Superbasin. Journal of the Geological Society of London 162, 777-787.  **Drake-Brockman J, Gee G, Thevissen J and Vieru C, 1996. Harts Range project, Annual Company Report 1995 field season - Els 7967, 7990, 7991, 7992, 7994, 8036, 8148, 8220, 8675, 8906, 9031, 9032, 9149, 7993, 8901 and 8906. PNC Exploration (Australia) Pty Ltd. Northern Territory Geological Survey, Open File Company Report CR1996?0286.  **Hollis JA, Beyer EE, Whelan JA, Glass LM, Donnellan N, Yaxley G, Armstrong R, Allen C and S Schersten A, 2011. Summary of results. NTGS laser U-Pb and Hf geochronology project: Pine Creek Orogen and Arunta Region, July 2008-May 2011. Northern Territory Geological Survey, Record 2010?004.  **Joklik GF, 1955. The geology and mica fields of the Harts Range, central Australia. Bureau of Mineral Resources, Australia. Bulletin 26.  **Maidment DW, 2005. Palaeozoic high-grade metamorphism within the Centralian Superbasin, Harts Range region, central Australia. Ph.D Thesis. Australian National University.  **Maidment DW, Hand M and Williams IS, 2013. High grade metamorphism of sedimentary rocks during Palaeozoic rift basin formation in central Australia. Gondwana Research 24(3-4), 865-885.  **Mithril Resources Ltd, 2010. Huckitta - High Grade Gold at Tibbs Prospect. ASX Announcement, 8 December 2010.   **Reno BL, Weisheit A, Beyer EE and PG Farias 2022. Jinka, Northern Territory. 1:100 000 geological map series explanatory notes, 6052. Northern Territory Geological Survey, Darwin.|16-MAY-23
27307|Yaningidjara Orthogneiss|Name source|Yaningidjara Hills (5553-090160) in southwestern part of Tea Tree 1:100 000 Sheet area.|16-MAY-23
27307|Yaningidjara Orthogneiss|Type section locality|5553-065154; striking hill of bare rock - an inselberg - at southwestern side of Yaningidjara Hills, shows clean exposure of augen gneiss with garnet, cut by foliated microgranite dykes about 1 m wide.|16-MAY-23
27307|Yaningidjara Orthogneiss|Extent|Southern part of Tea Tree 1:100 000 Sheet area.|16-MAY-23
27307|Yaningidjara Orthogneiss|Lithology|Coarse porphyritic granitic augen gneiss with rapakivi feldspars and clost of red-brown garnet; sillimanite visible in this section. Some microgranite dykes.|16-MAY-23
27307|Yaningidjara Orthogneiss|Relationships and boundaries|Intrudes Lander Rock beds; faulted against Mount Airy Orthogneiss.|16-MAY-23
27307|Yaningidjara Orthogneiss|Identifying features|Reason for Proposed Name: A distinctive body of garnetiferous granitic augen gneiss distinct from other granitic and metamorphic rocks in the area.|16-MAY-23
27307|Yaningidjara Orthogneiss|Age reasons|No isotopic date; probably Middle Proterozoic, by analogy with other orthogneisses in the area.|16-MAY-23
27307|Yaningidjara Orthogneiss|Proposed publication|Commentary on Reynolds Range-Aileron 1:100 0000 Special Map.|16-MAY-23
27307|Yaningidjara Orthogneiss|Defn Reference|80/20787|16-MAY-23
27307|Yaningidjara Orthogneiss|Reserved? Yes/No|Yes (as Granite)|16-MAY-23
23289|Yanungbi Volcanics|Name source|Yanungbi outstation (AMG PG803417), on the southwestern coast of Melville Bay, in the Gove 1:250 000 scale mapsheet area.|16-MAY-23
23289|Yanungbi Volcanics|Unit history|Previously undifferentiated "Spencer Creek Volcanics" of Dunnet (1965).|16-MAY-23
23289|Yanungbi Volcanics|Geomorphic expression|Typically recessive outcrop of blocks, boulders and low rubbly rises.|16-MAY-23
23289|Yanungbi Volcanics|Type section locality|Along Spencer Creek at lat. 12o21'10"S, long. 136o26'50"E (AMG PG574340, Arnhem Bay), where they comprise relatively fresh outcrop overlain unconformably by Mount Bonner Sandstone. Lower boundary stratotype along a linear resistant ridge between PG555405 and PG574407, which marks an unconformable contact between the Dhalinybuy Granite and relatively fine-grained banded and autobrecciated rhyolite of the Yanungbi Volcanics. This is interpreted as the base of a flow unit, sitting immediately above the granite with unconformity.|16-MAY-23
23289|Yanungbi Volcanics|Extent|Outcrop is restricted to two areas. The principal area is in the lower reaches of Spencer Creek and Cato River (~PG574340, northeastern Arnhem Bay 1:250 000 scale mapsheet area), 10 km northeast of Dhalinybuy outstation. A second area of outcrop lies to the northeast in the vicinity of Mount Bonner (PG700600, northwestern Gove 1).|16-MAY-23
23289|Yanungbi Volcanics|Thickness range|200 m. This unit has been locally eroded or removed prior to deposition of the overlying Gove Sandstone and Mount Bonner Sandstone. Poor exposure suggests the sequence is locally much thicker.|16-MAY-23
23289|Yanungbi Volcanics|Lithology|Pink, red or brown felsic igneous rock (rhyolite). It is aphyric to porphyritic with phenocrysts of K-feldspar. Localised development of contorted flow-banding and autobreccia. Local lens-shaped intrusions of aphyric rhyolite. Where this unit merges with the Latram Granite (e.g., PG563389) the texture becomes noticeably coarser and granophyric. These two are also petrologically and geochemically closely related (i.e. comagmatic). Also rare microdolerite.|16-MAY-23
23289|Yanungbi Volcanics|Depositional environment|Mainly extrusive but appears to be partly shallow intrusive, merging with the sub-volcanic Latram Granite. The extrusive rocks were probably emplaced by passive effusive processes as subaerial lava domes and coolees.|16-MAY-23
23289|Yanungbi Volcanics|Relationships and boundaries|Basal formation of the Spencer Creek Group. They lie unconformably on the metamorphic and granitic rocks of the Bradshaw Complex and the Orosirian Dhalinybuy Granite, and are in turn disconformably overlain by the quartzose Gove Sandstone. At the lower boundary stratotype, resistant fine-grained banded and autobrecciated rhyolite of the Yanungbi Volcanics, interpreted as the base of a flow unit, unconformably overlies the Dhalinybuy Granite. Nearby, similar aphyric rhyolite intrudes this granite. A weak thermal aureole has developed around the thicker intrusive bodies, resulting in low-grade contact metamorphism of the granite. The Yanungbi Volcanics are disconformably overlain by lithic and quartzose sandstones of the Gove Sandstone. At PG570420, the Gove Sandstone has removed the volcanic unit and sits unconformably on Dhalinybuy Granite. In other areas, all of the overlying formations of the Spencer Creek Group have been removed by erosion preceding deposition of the Mount Bonner Sandstone, and Yanungbi Volcanics are overlain unconformably by this coarse-grained siliciclastic unit.|16-MAY-23
23289|Yanungbi Volcanics|Age reasons|Palaeoproterozoic (Statherian). Interpreted to be comagmatic with the Latram Granite, which has an age of ~1710 Ma (Rawlings and others, in prep.), determined by single grain SHRIMP U-Pb geochronological techniques.|16-MAY-23
23289|Yanungbi Volcanics|Correlations|Rawlings and others (in prep.) and Rawlings (1994) suggest correlation with the upper parts of the Tawallah and Katherine River Groups in the southern and western McArthur Basin respectively. Locally, they correlate with the felsic igneous Fagan Volcanics in southern Arnhem Bay and northern Blue Mud Bay, and tentatively with the Gadabara Volcanics in eastern Blue Mud Bay mapsheet areas. These correlations are based on geochemical, petrological, lithostratigraphic and geochronological constraints, and the physical form of igneous units.|16-MAY-23
23289|Yanungbi Volcanics|References|DUNNET, D., 1965- Arnhem Bay/Gove, Northern Territory - 1:250 000 Geological Series. Bureau of Mineral Resources, Australia, Explanatory Notes, SD53-3, 4. **RAWLINGS, D. J., 1994- Characterisation and Correlation of Volcanism in the McArthur Basin and Transitional Domain, N.T. Proceedings The AusIMM Annual Conference, Darwin 1994, pp. 157-160. **RAWLINGS, D. J. and others, in prep- Arnhem Bay - Gove, Northern Territory - 1:250 000 Geological Map Series.  National Geoscience Mapping Accord, Explanatory Notes, SD53 -3, 4.|16-MAY-23
24596|Yarrawonga Volcanic Member|Name source|Yarrawonga zoo, grid reference GM 156206 (12o28'10"S, 130o59'E) Darwin 1:100 000 Sheet area.|16-MAY-23
24596|Yarrawonga Volcanic Member|Unit history|Previously unidentified. In lithology and stratigraphic position it correlates with the Mt Deane Volcanic Member on the Batchelor 1:100 000 sheet and volcanics within the Wildman Siltstone in the Annaburroo area of the Mary River 1:100 000 sheet.|16-MAY-23
24596|Yarrawonga Volcanic Member|Type section locality|Interval 74 m to 131 m (downhole) in Northern Territory Geological Survey's cored drill hole (DRP1) - co-ordinates GM177189 Koolpinyah 1:100 000 sheet. Core is stored at the Northern Territory Department of Mines and Energy Core Library, Darwin. Outcrop is identified by soft, brown highly weathered rocks exhibiting amygdaloidal and porphyritic textures.|16-MAY-23
24596|Yarrawonga Volcanic Member|Extent|Yarrawonga-Howard Springs area in the southwest corner of the Koolpinyah 1:100 000 Sheet area. 1. At headwaters of Mitchell Creek, adjacent to the North Australia Railway access road. 1. Adjacent to Radford road, south of the Stuart Highway.|16-MAY-23
24596|Yarrawonga Volcanic Member|Thickness range|Approximately 37 m consisting of: rhyolite and perlite 2m; dacite 25 m; ignimbrite 10m.|16-MAY-23
24596|Yarrawonga Volcanic Member|Lithology|Three recognisable units - 1. Basal ignimbrite - highly altered, sericitic, acid volcanic with a fragmental texture and compaction structures suggesting welded tuff origin, interbedded with pyritic, carbonaceous shale and siltstone.  2. Dacite weakly chloritised, containing minor pyrite, quartz amygdales and feldspar phenocrysts, minor interbedded colourbanded pyritic, carbonaceous siltstone and slate.  3. Top unit of rhyolite and perlite.|16-MAY-23
24596|Yarrawonga Volcanic Member|Relationships and boundaries|The Member is overlain and underlain by colour banded, pyritic carbonaceous silty shale of the Wildman Siltstone.|16-MAY-23
24596|Yarrawonga Volcanic Member|Age reasons|Early Proterozoic, as it forms part of the Early Proterozoic metasedimentary and volcanic sequence of the Pine Creek Geosyncline, which overlies verified Archaean age rocks.|16-MAY-23
24596|Yarrawonga Volcanic Member|Proposed publication|Koolpinyah Explanatory Notes (Northern Territory Geological Survey)|16-MAY-23
41858|Yaya Metamorphic Complex|Name source|Yaya Creek  23o 18' 00" S, 131o 38' 00" E, MOUNT LIEBIG.|16-MAY-23
41858|Yaya Metamorphic Complex|Unit history|Previously included within undifferentiated gneiss, schist, amphibolite, quartzite, granite, dolerite and pegmatite of the Arunta Complex, and unnamed quartzite of the Arunta Complex (Ranford 1969). Includes parts of the Speares Metamorphics in HERMANNSBURG (Warren and Shaw 1995).|16-MAY-23
41858|Yaya Metamorphic Complex|Constituents|Alkipi Metamorphics and unnamed lithological units.|16-MAY-23
41858|Yaya Metamorphic Complex|Geomorphic expression|Expression varies from prominent bouldery hills to low rounded rocky hills and less common isolated rocky outcrops and strike ridges.|16-MAY-23
41858|Yaya Metamorphic Complex|Type section locality|Type locality for Alkipi Metamorphics is contained in definition of the unit. Reference locality for cordierite granulites is on western side of a large hill 6 km south of Kakalyi Bore) at 23o 15' 27.43" S, 131o 33' 13.93" E (WGS 84), MOUNT LIEBIG. Reference locality for interlayered pelitic and mafic granulite is at 23o 13' 28.49" S, 131o 44' 37.93" E.|16-MAY-23
41858|Yaya Metamorphic Complex|Extent|In hills across northern half of MOUNT LIEBIG, north of Belt Range and Mount Liebig, and adjacent regions of western HERMANNSBURG. Extends west into northern and central MOUNT RENNIE.|16-MAY-23
41858|Yaya Metamorphic Complex|Lithology|Garnet-biotite-sillimanite metapelite, metapsammite, quartzose metasediment and quartzite, strained biotite granite, felsic migmatite, massive cordierite granulite, diopside-quartz ? grossular calc-silicate rock, interlayered mafic granulite and metapelite, mafic amphibolite.|16-MAY-23
41858|Yaya Metamorphic Complex|Relationships and boundaries|Intruded by the Illili Suite, Waluwiya Suite, Papunya Igneous Complex, Ulambaura Granodiorite, Belt Granite and unnamed charnockite. Intruded by Stuart Pass Dolerite (Warren and Shaw 1995) and unconformably overlain by Heavitree Quartzite.|16-MAY-23
41858|Yaya Metamorphic Complex|Age reasons|late Palaeoproterozoic. A sample of massive cordierite granulite from 23o 15' 27.43" S, 131o 33' 13.93" E has a maximum deposition age of 1661 +/- 10 Ma, based on SHRIMP U-Pb dating of detrital zircons, with metamorphic zircon rims with an age of 1638 +/- 8 Ma (Kinny 2002). Two samples of metapelite have maximum deposition ages of 1670-1650 Ma, based on SHRIMP U-Pb dating of detrital zircons, with metamorphic zircon rims with ages of ~1640 Ma (Kinny 2002). A sample of quartzite from  23o14' 20.40" S, 131o 50' 25.82" E  has an older maximum deposition age of 1760 Ma (Cross et al in prep). Intruded by 1640-1635 Ma granites.|16-MAY-23
41858|Yaya Metamorphic Complex|Comments|Interpreted to be a succession of metasediments that was intruded by granites and mafic rocks, metamorphosed to granulite facies during 1640-1635 Ma Liebig Orogeny, and reworked during 1590-1560 Ma Chewings Orogeny. It is possible that some mafic and felsic gneisses may have an extrusive rather than intrusive precursor. Due to the degree of deformation and metamorphism and heterogeneity of rocktypes, it is possible that this unit includes rocks of significantly different ages.|16-MAY-23
41858|Yaya Metamorphic Complex|References|Cross A, Claoue-Long J, Scrimgeour IR, Close DF & Edgoose CJ, in prep. NTGS-GA Geochronology project, Report 6. Northern Territory Geological Survey, Record **Kinny PD, 2002. SHRIMP U-Pb geochronology of Arunta Province samples from the Mount Liebig and Lake Mackay 1:250 000 mapsheets. Northern Territory Geological Survey, Technical note 2002-015. **Ranford LC, 1969. Mount Liebig, Northern Territory (First Edition). 1:250 000 geological map series explanatory notes, SF52-16. Bureau of Mineral Resources, Australia. **Scrimgeour IR, Close DF & Edgoose CJ, in prep. Mount Liebig, Northern Territory (Second Edition) 1:250 000 geological map series explanatory notes, SE 52-16. Northern Territory Geological Survey, Darwin. **Warren RG and Shaw RD 1995. Hermannsburg, Northern Territory (Second Edition). 1:250 000 geological map series explanatory notes, SF-53-13. Northern Territory Geological Survey, Darwin.|16-MAY-23
24597|Yeeradgi Sandstone|Name source|Yeeradgi Rockhole, GR 223468, Bonney 1:100 000 Sheet area, Bonney Well 1:250 000 Sheet area.|16-MAY-23
24597|Yeeradgi Sandstone|Type section locality|In SE Bonney 1:100 000 Sheet area; base at GR 443355, 8 km W of Kurundi HS (latitude 20o30'00"S, longitude 134o41'00"E), where formation overlies Unimbra Sandstone conformably, extending SE to top at GR 442352, where formation is conformably overlain by Coulters Sandstone. (Type section follows on directly from that of Unimbra Sandstone). Section dips about 80oS, and comprises about 200 m of mainly friable, purplish, fine to medium grained, cross-bedded, variably lithic arenite.|16-MAY-23
24597|Yeeradgi Sandstone|Extent|N and central parts of Davenport Province - in Bonney Well, Frew River, Barrow Creek, and Elkedra 1:250 000 Sheet areas.|16-MAY-23
24597|Yeeradgi Sandstone|Thickness range|Generally between 200 m and 800 m.|16-MAY-23
24597|Yeeradgi Sandstone|Lithology|Ridge-forming to recessive cross-bedded arenite with sparse to abundant lithic/kaolinic/feldspathic/muscovite component, grading to arkose or wacke; slate and siltstone common in upper part; minor lenses of porphyritic felsic volcanics.|16-MAY-23
24597|Yeeradgi Sandstone|Relationships and boundaries|Conformable on Unimbra Sandstone; overlain conformably by Arabulja Volcanics, Newlands Volcanics, and Coulters Sandstone; locally interfingers with Newlands Volcanics, and in NW Davenport Range 1:100 000 Sheet area locally overlain unconformably by Coulters Sandstone. Intruded by granophyre sills. Base of Yeeradgi Sandstone taken at change from ridge-forming arenite to Unimbra Sandstone to less resistant or recessive arenite: top taken at top of recessive sedimentary beds.|16-MAY-23
24597|Yeeradgi Sandstone|Age reasons|Younger than 1870 Ma (U-Pb zircon date on volcanics in Warramunga Group, which is unconformably overlain by Hatches Creek Group), older than 1640 Ma (Rb-Sr whole-rock approximate date on granite intruding Hatches Creek Group).|16-MAY-23
24597|Yeeradgi Sandstone|Comments|Remarks: Part of the Wauchope Subgroup of the Hatches creek Group. Unit of mainly labile arenite which is less resistant than underlying and overlying quartzose arenites.|16-MAY-23
24597|Yeeradgi Sandstone|Defn Reference|86/25362|16-MAY-23
24597|Yeeradgi Sandstone|Proposer|Stewart A.J.|16-MAY-23
23310|Yirrkala Formation|Name source|From Yirrkala, the old mission site on the Gove Peninsula in far northeastern Arnhem Land, at 12o15'05"S, 136o53'20"E.|16-MAY-23
23310|Yirrkala Formation|Unit history|In places this unit is lithologically similar to, but not stratigraphically equivalent to, rocks described by Skwarko (1966) as 'unit A' of his 'inland belt', and was included within the Mullaman Beds. Use of the name Mullaman Beds has been discouraged (Hughes, 1978) due to the recognised stratigraphc inadequacy of the term in its original form, where it was used to describe most Mesozoic rocks in the northeastern Northern Territory. The name Yirrkala Formation was initially proposed to describe nonmarine rocks in Arnhem Land, but it also applies to rocks distributed much farther to the south along the western margin of the Gulf of Carpentaria, south until the Northern Territory/Queensland border. It is anticipated that further mapping will amost certainly extend the known westward distribution of the unit.|16-MAY-23
23310|Yirrkala Formation|Geomorphic expression|Palaeoenvironment: The unit generally represents high-energy fluvial deposition in channels, and coarse-grained valley fills. Most outcrops conform to sandy bedform, channel, and gravel bar architectural elements in Miall's (1985) classification of fluvial deposits.|16-MAY-23
23310|Yirrkala Formation|Type section locality|Lower boundary stratotype: Base of a 7.5 m interval of orange, coarse-grained, trough cross-bedded sandstone exposed along the banks of Wonga Creek, about 40 km southwest of Nhulunbuy at 12o29'15"S, 136o34'00"E on the Arnhem Bay-Gove 1:250 000 Sheet. The base of the unit is identified by a prominent disconformity with several metres of erosional relief. Immediately beneath the disconformity are pale coloured rocks of the Walker River Formation.  Reference Section: 50 m of white sandstone exposed along the banks and to the sides of 'Tiger Creek', at approximately 13o31'30"S, 135o14'50"E on the eastern flank of the Parsons Range on the Blue Mud Bay-Port Langdon 1:250 000 Sheet. The local formation base is identified by a chert cobble and pebble conglomeratic lag, mantling a well developed angular unconformity on the Palaeoproterozoic Parsons Range Group. The upper boundary of the unit was not observed, but is likely to occur a short distance above the top of the measured section.|16-MAY-23
23310|Yirrkala Formation|Extent|The unit occurs in two main areas. Firstly, as a broad semi-continuous low-lying plateau in the northeastern part of the Arnhem Bay-Gove 1:250 000 Sheet area, between Melville Bay and Wanyamera Point, and Arnhem Bay and Dalywoi Bay. The exposed area of this plateau (now partly dissected) is about 1500 km2. The greatest thickness and extent of the Yirrkala Formation occurs on the Arnhem Bay-Gove 1:250 000 Sheet, in an area within about 50 km to the southwest of Nhulunbuy. Secondly, the unit occurs as thinner, patchy palaeovalley fill and terraced deposits in the elevated parts of high-standing basement ranges. The unit has been recognised on the upper flanks of the Mitchell Range and Parsons Range on the Blue Mud Bay-Port Langdon 1:250 000 Sheet, and also in the elevated parts of the Yiyintyi Range on the Mount Young 1:250 000 Sheet at about latitude 15o25'S.|16-MAY-23
23310|Yirrkala Formation|Thickness range|Range 5 to 50 m: typically 8 to 15 m in outcrop, but probably much thicker in the subsurface, as shown in drill logs for 3 stratigraphic drillholes in the area surrounding Nhulunbuy (Dodson, 1967).|16-MAY-23
23310|Yirrkala Formation|Lithology|Sandstone: white to pale grey, poorly to moderately sorted, fine- to very coarse-grained: massive to thickly planar bedded, with large-scale trough cross-bedding with set thicknesses up to 2 m at the base, and planar cross-bedding in the middle and upper parts with rare dispersed rounded pebble-sized chert clasts. Commonly forms fining-upward grain-size cycles, with chert pebble lags overlying local base-of-channel scours. Upper, finer-grained parts of the unit (or sub-cycles within the unit) contain rare, moderately to poorly preserved external moulds of segmented plant fossils on upper bedding surfaces.|16-MAY-23
23310|Yirrkala Formation|Depositional environment|The unit generally represents high-energy fluvial deposition in channels, and coarse-grained valley fills. Most outcrops conform to sandy bedform, channel, and gravel bar architectural elements in Miall's (1985) classification of fluvial deposits.|16-MAY-23
23310|Yirrkala Formation|Relationships and boundaries|In most exposures the unit overlies marine rocks of the Walker River Formation with disconformity or Palaeoproterozoic sedimentary rocks with angular unconformity. In the subsurface the unit overlies Proterozoic metasediments and granites with nonconformity (Dodson, 1967).|16-MAY-23
23310|Yirrkala Formation|Age reasons|Plant macrofloras collected from this unit are relatively poorly preserved and consist of long-ranging forms, which may only be considered as Late Mesozoic in age (cf. Skwarko, 1966). The unit is correlated with the nonmarine sequence in three stratigraphic drillholes near Nhulunbuy; siltstone interbedded with the arkosic sandstones in drillhole DDH2 at 64 m depth has been dated by palynology as late Albian (Evans, in Dodson, 1967). Furthermore, on the basis of regional lithostratigraphic correlations, outcrops of the unit in the Wonga Creek area, about 40 km southwest of Nhulunbuy, disconformably overlie marine Cretaceous rocks of Albian age (Krassay, 1994). Therefore, the likely age of the unit in most places is Albian or younger (up to Cenomanian).|16-MAY-23
23310|Yirrkala Formation|Proposed publication|Australian Journal of Earth Science: "Lithostratigraphy of the mid-Cretaceous shelf system in Arnhem Land, NT".|16-MAY-23
23310|Yirrkala Formation|Category|2|16-MAY-23
23310|Yirrkala Formation|Proposer|Krassay A.A.|16-MAY-23
23310|Yirrkala Formation|Resdate|09-JAN-1995|16-MAY-23
23310|Yirrkala Formation|Reserved? Yes/No|Yes|16-MAY-23
23312|Yuduyudu Formation|Name source|Yuduyudu outstation (AMG PG779470), on the westen coast of Melville Bay, Gove 1:250 000 scale mapsheet area.|16-MAY-23
23312|Yuduyudu Formation|Unit history|Previously undifferentiated "Spencer Creek Volcanics" of Dunnet (1965).|16-MAY-23
23312|Yuduyudu Formation|Geomorphic expression|Low dissected lateritic areas, with scattered scree.|16-MAY-23
23312|Yuduyudu Formation|Type section locality|Poor-quality outcrop around lat. 12o11'40"S, long. 136o30'40"E (AMG PG645515, Gove 1:250 000 scale mapsheet area). The base of the section is the lower boundary stratotype at PG650510 and the top of the section is at PG636512. However, no top boundary stratotype is defined due to lack of an exposed upper contact.|16-MAY-23
23312|Yuduyudu Formation|Extent|Outcrop is confined to a very small area 18 km northwest of Yanungbi outstation, in northeastern Arnhem Bay and northwestern Gove 1:250 000 scale mapsheet areas.|16-MAY-23
23312|Yuduyudu Formation|Thickness range|150 to 250 m at the type section. To the north and south, the sequence has been removed by the unconformity at the base of the overlying Mount Bonner Sandstone.|16-MAY-23
23312|Yuduyudu Formation|Lithology|Outcrop is very poor, and comprises scattered scree and slabs of pink quartzose or brown ferruginous lithic fine-grained sandstone and mudstone, and  minor medium-grained sandstone. The outcrop pattern suggests these are interbedded on a metre-scale. Otherwise, little is known of its rock types and internal stratigraphy.|16-MAY-23
23312|Yuduyudu Formation|Depositional environment|The quality of outcrop does not permit an accurate assessment of the environment of deposition, but a shallow-water low-energy setting is envisaged.|16-MAY-23
23312|Yuduyudu Formation|Relationships and boundaries|Middle sedimentary formation of the Spencer Creek Group. Apparently conformable between the Gove Sandstone and Cato Volcanics. The lower contact is marked by a gradation from clean white sandstone into more ferruginous and lithic sandstone and mudstone. The contact with overlying Cato Volcanics is very poorly exposed and is tentatively interpreted as conformable to mildly disconformable. Along strike, beyond the current exposures, the Yuduyudu Formation is probably unconformably overlain by Mount Bonner Sandstone.|16-MAY-23
23312|Yuduyudu Formation|Age reasons|Palaeoproterozoic (Statherian). Constrained by the underlying and overlying Yanungbi and Cato Volcanics, which are ~1710 Ma (Rawlings and others, in prep.).|16-MAY-23
23312|Yuduyudu Formation|Correlations|Rawlings and others (in prep.) and Rawlings (1994) suggest correlation with the upper parts of the Tawallah and Katherine River Groups in the southern and western McArthur Basin respectively. Locally, it correlates with the Fagan Volcanics in southern Arnhem Bay and northern Blue Mud Bay mapsheet areas.|16-MAY-23
23312|Yuduyudu Formation|References|DUNNET, D., 1965- Arnhem Bay/Gove, Northern Territory - 1:250 000 Geological Series. Bureau of Mineral Resources, Australia, Explanatory Notes, SD53-3, 4. **RAWLINGS, D. J., 1994- Characterisation and Correlation of Volcanism in the McArthur Basin and Transitional Domain, N.T. Proceedings The AusIMM Annual Conference, Darwin 1994, pp. 157-160. **RAWLINGS, D. J. and others, in prep- Arnhem Bay - Gove, Northern Territory - 1:250 000 Geological Map Series.  National Geoscience Mapping Accord, Explanatory Notes, SD53 -3, 4.|16-MAY-23
23318|Yungkulungu Formation|Name source|After Yungkulungu Ridge, a prominent  northwest-trending linear  topographic  high (6.5 km long and 800 m wide) located between Gosse River and Mount Rugged (GR MU210450; lat. l9deg42'08"S, long. 134deg27'58"E) and centred on Rocky Range trigonometric station.|16-MAY-23
23318|Yungkulungu Formation|Unit history|Previously mapped as part of Warramunga Group on the Tennant Creek one-inch-to-one-mile geological map (Crohn and Oldershaw, 1965), later informally differentiated as a subunit (Ew5) on TENNANT CREEK First Edition (Mendum and Tonkin 1971). The ignimbritic (Enyi) and volcanic rock (Enyv) sequences have  been  previously mapped as Proterozoic quartz-feldspar- and quartz­ porphyry or granite (Crohn and Oldershaw 1965, Mendum and Tonkin 1976).|16-MAY-23
23318|Yungkulungu Formation|Geomorphic expression|The unit crops out as broad, low hills or rises surrounded by flat plains of recent sheet­ flood sands.|16-MAY-23
23318|Yungkulungu Formation|Type section locality|Reference sections: No single type section is available due to faulting. The four reference sections indicated below cover full extent of Formation, with base of each section as first location recorded: (1) GR MU380190 (lat. 19deg43'25"S, long. 134deg24"35"E)  to  GR MU395218  (lat. 19deg41'55"S,long. 134deg25'25"E) uppermost sequence; (2) GR MU460130 (lat. 19deg46'40"S, long 134deg29'05"E) to GR MU434130 (lat. 19deg46'40"S, long. 134deg27'35"E) and GR MU430140 lat. 19deg46'12"S, long. 134deg27'20"E)  to GR MU428170 (lat. 19?44'3"S, long. 134deg27'20"E); (3) GR MU458220 (lat. 19deg41'25"S and long. 13deg 29'00"E)  to  GR MU441246  (lat. 19deg40'25"S,  long. 134deg28'00"E);  (4) GR MU510180  (lat. 19deg44'00"S, long. 134deg32'00"E) to GR MU468224 (lat. 19deg41'35"S,  long. 134deg29'32"E) lowermost sequence.|16-MAY-23
23318|Yungkulungu Formation|Extent|Exposed over an area of approximately 70 km2 centred on Yungkulungu Ridge (GR  MU210450;  lat. 19deg42'08"S,  long. 134deg27'58"E). Drilling together with sporadic out- crops as small hills and low rises have confirmed eastern extension of Yungkulungu Formation (in excess of 500 km2) to south-central margin of GOSSE RIVER (GR MT715908; lat. 19deg59'40", long. 134deg43'40"E). Drilling on the Rover field, 70 km SW of Tennant Creek, has revealed volcaniclastic and siliciclastic rocks interpreted as part of the Yungkulungu Formation (Huston et al 2020, Cross et al 2021, Cross et al 2022). Drillholes are enclosed in this area (lat. 19deg54'19\"S to 20deg1'11\"S, and long. 133deg17'47\"E to 133deg43'29\"E).|16-MAY-23
23318|Yungkulungu Formation|Lithology|Upper sequence of Yungkulungu Formation (Eny8)  is dominated by 0.3 m-thick beds of medium- to coarse-grained lithic arenite characterised  by  black  heavy  mineral  laminations  in  broad trough (or festoon) cross-bedded foresets. These, together with interbedded siltstone,  are  1 900 m­ thick. Conglomeratic horizons or lenses are characterised by rounded rhyolite or rhyodacite pebbles. Base  of  Eny8   has  interbedded  tuff,  ignimbrite  and minor rhyolite flows up to 200 m-thick   (Enyj). This sequence conformably overlies over 3 000 m of thick-bedded, medium-  to  coarse-grained,  rhyolitic to rhyodacitic crystal-lithic tuff, rhyolite to rhyodacite lava flows and ignimbrite, interbedded  with fine­ grained felsic tuff and sandstone  (Enyv).  Both biotite lamprophyre and dolerite intrude Enyv, with the latter only noted in drillcore.|16-MAY-23
23318|Yungkulungu Formation|Depositional environment|Predominantly shallow marine.|16-MAY-23
23318|Yungkulungu Formation|Relationships and boundaries|Where  sequence thins to the north (GR MU441246; lat. 19deg40'25"S, long. 134deg28'00"E) and west (GR MU315183; lat. 19deg43'50"S, long. 134deg20'50"E), the Yungkulungu Formation is faulted against underlying Warramunga Formation. To the south, base of Yungkulungu Formation  is intruded by Mumbilla Granodiorite (GR MU346140; lat. 19deg46'10"S, long. 134deg22'35"E; bottom boundary stratotype). It is unconformably overlain by Neoproterozoic - Cambrian Rising Sun Conglomerate (GR MU307183; lat. 19deg43'50"S, long. 134deg20'25"E) or Cambrian sedimentary rocks. Conformable relationship with overlying, massive quartz arenite (GR MU394216; lat. 19deg42'00"S, long. 134deg25'20") mapped as undifferentiated Flynn Subgroup but which is correlated with Brumbreu Formation on FLYNN. Top  boundary  stratotype:  Conformable  contact  with quartz arenites (GR MU394216;  lat.  19deg42'00"S, long. 134deg25'20") which are mapped as undifferentiated Flynn Subgroup but correlated with the Brumbreu Formation on FLYNN. Bottom boundary stratotype: Intrusive contact with Mumbilla Granodiorite (GR MU346140; lat. 19deg46'10"S, long. 134deg22'35"E).|16-MAY-23
23318|Yungkulungu Formation|Identifying features|Forms broad, low rises and rounded hills in contrast to mesas and buttes of Warramunga Formation. Also distinguished by its interbedded  felsic  volcanic  rock  component Enyi) and thick sequence of coarse-grained rhyolitic to rhyodacitic lava flows (Enyv). The sedimentary sequence is characterised by tabular, maroon-coloured, fine- to coarse-grained lithic arenite, dominated by felsic volcanic detritus.|16-MAY-23
23318|Yungkulungu Formation|Structure and Metamorphism|Upright isoclinal folds with fold wavelength dependent on relative competency of beds.|16-MAY-23
23318|Yungkulungu Formation|Age reasons|Correlated with  Bernborough Formation, which is dated at 1840+/-8 to 1845+/-4 Ma by Compston (1994). Intruded by, and thus predates, Channingum Granite and Mumbilla  Granodiorite, dated at 1840+/-9 Ma and 1850+/-6 Ma respectively (Compston  1994). Cross et al (2021) and Cross et al (2022) reported maximum depositional ages of ca 1854-1842 Ma on volcaniclastic and siliciclastic rocks in the Rover field.|16-MAY-23
23318|Yungkulungu Formation|Correlations|The Yungkulungu Formation represents nearly the entire Flynn Subgroup as exposed on FLYNN; the upper sedimentary lithofacies (Eny8) is probably equivalent to the Brumbreu and Wundirgi Formations, while the felsic volcanic rock sequence (Enyv) is probably equivalent to the Bernborough and Monument Formations.|16-MAY-23
23318|Yungkulungu Formation|Defn author|Morrison, R.S., 1995.|16-MAY-23
23318|Yungkulungu Formation|References|Cross AJ, Huston DL and Farias PG, 2021. Summary of results. Joint NTGS?GA geochronology project: Rover mineral field, January-June 2020. Northern Territory Geological Survey, Record 2021-003.  **Cross AJ, Farias PG and Huston DL, 2022. Summary of results. Joint NTGS?GA geochronology project: Rover mineral field, Warramunga Province, July-December 2020. Northern Territory Geological Survey, Record 2022-005.  **Huston DL, Cross A, Skirrow R, Champion D and Whelan J, 2020. The Tennant Creek mineral field and Rover fields: Many similarities but some important differences: in `Annual Geoscience Exploration Seminar (AGES) Proceedings, Alice Springs, Northern Territory, 24?25 March 2020?. Northern Territory Geological Survey, 70?83.|16-MAY-23
27310|Zamu Dolerite|Name source|Zamu Creek mine 13o34'S, 132o43'E. Sheet SD/53/65 Mt Evelyn 1:250 000.|16-MAY-23
27310|Zamu Dolerite|Unit history|Mafic rocks of Zamu Creek area named 'Zamu Complex' by Stewart (1959); name extended to all the mafic rocks of South Alligator area by Walpole (1962); name extended to include those mafic rocks of the Alligator Rivers Uranium Field which predate the 1800 m.y. event by Needham et al. (1974) and Smart et al. (1976). This proposal is another extension of the use of the name plus a variation in the name from Zamu Complex to Zamu Dolerite.|16-MAY-23
27310|Zamu Dolerite|Type section locality|As described by Bryan (1962); in the vicinity of the Zamu Creek mine. Two parallel masses about 1.6 km north of the Malone Creek Granite of mainly  dolerite (diallage, hypersthene dolerite) and minor biotite-hornblende-diallage pegmatite.|16-MAY-23
27310|Zamu Dolerite|Extent|Throughout the Pine Creek Geosyncline, particularly in a belt <30 km wide trending NW between the headwaters of the West Alligator and Katherine Rivers; also in the Oenpelli, Jabiru, Burrundie, Brocks Creek and Rum Jungle areas, and possible counterparts in the Mt Masson, Daly River/Wingate Plateau and Katherine/Yeuralba/Maranboy areas. Outacrops on the Darwin, East Alligator, Mt Evelyn, Pine Creek, Fergusson River and Katherine 1:250 000 Sheet areas.|16-MAY-23
27310|Zamu Dolerite|Thickness range|<1 m - 1 km.|16-MAY-23
27310|Zamu Dolerite|Lithology|Doleritic with minor differentiates, to amphibolitic. Amphibolites mainly in the medium-high grade terrain of the Alligator Rivers Uranium Field, and in contact aureoles of younger granites. Total or partial chlorite replacement in restricted areas, notably at sites of uranium mineralisation.|16-MAY-23
27310|Zamu Dolerite|Relationships and boundaries|Mainly conformable sills folded and in most places metamorphosed with the enclosing strata by a regional 1800 m.y. event. Chilled margins evident where unmetamorphosed, and host rocks metamorphosed. Truncated by early Carpentarian granites and invaded?? by granitic veins in places. Unconformably overlain by Edith River Volcanics and Kombolgie Formation of early Carpentarian age.|16-MAY-23
27310|Zamu Dolerite|Age reasons|Late Lower Proterozoic; emplaced before the 1800 m.y. orogenic event into Lower Proterozoic (2250-1800 m.y.) strata.|16-MAY-23
