Citation

Geoscience Australia provides most of its products for free under a Creative Commons Attribution 3.0 Australia Licence. We only require that you reference the use of our data or information using the following citation:
Owen, M. & Wyborn, D., 1979. Geology and geochemistry of the Tantangara and Brindabella 1:100 000 Sheet areas, New South Wales and Australian Capital Territory. Scale 1:100000. Bulletin  204. Bureau of Mineral Resources, Geology and Geophysics, Canberra.

Abstract

The Tantangara and Brindabella 1:100 000 Sheet areas cover 5030 km2 between latitudes 35' and 36°S and longitudes 148°30' and 149°E, in the southern part of the Lachlan Fold Belt in New South Wales, The earliest record of sedimentation in the two Sheet areas is of mid-Ordovocian quartzrich distal flysch, becoming more proximal in the Late Ordovician, In the west, a volcanic arc erupted tholeiitic basalis and (?Iater) shoshonites during the middle to Late OrdovicialL A phase of deformation in the latest Ordovician mainly to the west of the mapped area interrupted flysch sedimentation, which recontinued in a meridional trough-the source being the deformed Ordovician flysch to the west, After a further deformational event-which destroyed the trough during the L1andoverian-a shelf environment became established in the east and centre, and shelf sedimentation continued in the centre almost to the end of the Silurian, when major deformation terminated it, Elsewhere, S then ?I-type felsic volcanism-mostly subaerial, depositing ignimbrites-was widespread during the Wenlockian and Ludlovian; comagmatic S and I-type granitoids intruded the volcanic piles, and tholeiitic magmas intruded, simultaneously in the west, during the Late Silurian. The felsic volcanics and granitoids are the anatecticproducts of a prolonged period of high heat flow in the crust which peaked in the Early Silurian and resulted in metamorphism to at least the upper greenschist facies grade. At the start of the Early Devonian, S-type volcanics-again subaerial felsic ignimbriteserupted in the southwest, slightly later, I-type volcanics erupted from at least two large stratovolcanoes in the north, and a comagmatic granitoid suite intruded concurrently in the north and south. These Early Devonian volcanics and granitoids are believed to be the final products of the high heat flow in the Silurian. In the north during the late stage of volcanism, black mud accumulated locally in a restricted marine environment, and arenites, some originating as mudflows on the sides of the stratovolcanoes, were deposited in alluvial fans. During the latter half of the Early Devonian, open-marine sedimentation became established briefly in this northern area; it was terminated by a thick f1uviatile sequence of conglomerate, sandstone, and shale-much of it deposited in cycles-in the northwest during the early Middle Devonian. This marked the final phase of Palaeozoic sedimentation. After further folding and faulting, probably in the Carboniferous, an extensive peneplain developed during the late Palaeozoic and Mesozoic. Sandwiched between two episodes of Tertiary uplift, which progressively elevated the peneplain, lacustrine sediments accumulated locally in the west and south during the Miocene. Extensive colluvium has formed on the mountain slopes during the Quaternary, and alluvium is being deposited along the courses of many streams at the present time. Known mineral deposits are small and mostly uneconomical. They include Mississippi Valley-type lead-zinc in Upper Silurian limestone; skarn deposits containing magnetite and minor lead-zinc associated with Silurian S-type granitoids; tungsten-bismuth and magnetite associated with Lower Devonian I-type granitoids; base metals associated with SilurianDevonian acid volcanics; and gold in Tertiary gravel and Holocene alluvium.
Google map showing geographic bounding box with values North bound -35.0 East bound 149.0 West bound 148.5 South bound -36.0
Downloads
For information on acquiring this product,
please contact Geoscience Australia Client Services via:

fax:
+61 2 6249 9960; or
phone:
1800 800 173 (within Australia);
 
+61 2 6249 9966 (outside Australia).

Product Type/Sub Type

dataset - GA Publication - Bulletin

Constraints

license
Creative Commons Attribution 3.0 Australia Licence

IP Owner

Commonwealth of Australia (Geoscience Australia)

Author(s)

Date (publication)

1979

Product Type

dataset

Topic Category

geoscientificInformation

Keywords

GA Publication
Bulletin
geochemistry
geology
Earth Sciences

Resource Language

English

Resource Character Set

utf8

Resource Security Classification

unclassified

Geographic Extent

North bound
-35.0
East bound
149.0
West bound
148.5
South bound
-36.0

Lineage

Unknown

Digital Transfer Options

onLine

DISTRIBUTION Format

pdf

Distributor

Role
distributor
Organisation Name
Geoscience Australia
City
Canberra
Administrative Area
ACT
Postal Code
2601
Country
Australia
Email Address

Metadata File Identifier

a05f7892-7fa0-7506-e044-00144fdd4fa6

Metadata Standard Name

ANZLIC Metadata Profile: An Australian/New Zealand Profile of AS/NZS ISO 19115:2005, Geographic information - Metadata

Metadata Standard Version

1.1

Metadata Date Stamp

1996-10-29

METADATA SECURITY CLASSIFICATION

unclassified

Metadata Contact

Role
pointOfContact
Organisation Name
Geoscience Australia
City
Canberra
Administrative Area
ACT
Postal Code
2601
Country
Australia
Email Address
Downloads
For information on acquiring this product,
please contact Geoscience Australia Client Services via:

fax:
+61 2 6249 9960; or
phone:
1800 800 173 (within Australia);
 
+61 2 6249 9966 (outside Australia).