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Geophysical interpretation of the central Olympic Cu-Au ProvinceNote: This metadata describes the dataset in accordance with the ANZLIC (Australia New Zealand Land Information Council) Core Metadata Guidelines Version 2. Dataset citationANZLIC unique identifier: ANZCW0703004741 Title: Geophysical interpretation of the central Olympic Cu-Au Province CustodianCustodian: Geoscience Australia Jurisdiction: Australia DescriptionAbstract: The Olympic Cu-Au Province, of the eastern Gawler Craton, lies beneath the sedimentary sequences of the Stuart Shelf. Older basement rocks are Late Archaean metamorphics, and the Proterozoic Donington Suite, Hutchison Group, and Wallaroo Group. Except for parts of the Gawler Range Volcanics, none of the basement crops out and is covered by sequences exceeding 3 km thickness, in places. Interpretation of units and structures was via gravity and airborne magnetic data. Some geological calibration was done by checking exploration drill logs or by examining the core. When core was examined, petrophysical properties were measured and used to constrain the interpretation. ANZLIC search words:
Spatial domain:
Geographic extent name: GAIRDNER - GAIRDNER - Drainage Divisions and Major River Basins - Australia Geographic extent polygon: 135.965 -29.883, 138.215 -29.883, 138.215 -32.58, 135.965 -32.58, 135.965 -29.883, Note: The format for each Geographic extent name is: Name - Identifier - Category - Jurisdiction (as appropriate) See GEN Register
Data currencyBeginning date: 2002-05-08 Ending date: 2002-06-03 Dataset statusProgress: In Progress Maintenance and update frequency: Not Known Access
Access constraints: Licence required. Free Data DownloadData qualityLineage: The interpretation was done from airborne magnetic data and drillhole logging. The magnetic data are from numerous government and company datasets and were compiled by GA and PIRSA. Drillhole data are from PIRSA logs and logging by the authors. Gow's interpretation (1996: Geological evolution of the Stuart Shelf and Proterozoic iron oxide-associated mineralization: Insights from regional geophysical data. Unpublished PhD thesis) was the starting point for this work. Geological cross-sections derived from our interpretation were tested using ModelVision. The model of depth-to-basement was calculated using the ANUDEM topographic modelling algorithm and was based primarily on drill hole data and the mapped limits of basement outcrop. No attempt has been made to smooth the depth-to-basement contours which have been computer-generated from the gridded model. The vector data was digitised and compiled using ArcInfo 8.0.2. Depth-to-basement data was gridded and contoured using the Topogrid module of ArcInfo 8.0.2 and the Spatial Analyst extension of Arcview 3.2. Geophysical and depth-to-basement images were exported as BIL files from ER Mapper 5.5. Positional accuracy: Interpretation and digitisation were done at 1:250 000 scale for presentation at 1:500 000 scale. It is not designed to be used at scales larger than 1:250 000 (e.g., 1:100 000 scale). Attribute accuracy: The geological units are defined by geophysical character with limited ground truthing from irregularly distributed drilling. In the west of the sheet area, there are outcrops of the Gawler Range Volcanics. Unit names not appearing in GA's Stratigraphic Names Database are informal and come from Gow (1996: Geological evolution of the Stuart Shelf and Proterozoic iron oxide-associated mineralization: Insights from regional geophysical data). Where linework (boundaries, faults etc) is classified, it is done so according to the author's confidence in their interpretation. Logical Consistency: Attribute data for geological layers comply to the GA Geoscience Data Dictionary version 2002.02 (www.ga.gov.au/general/technotes/20011112_53.jsp). All lines, points, and polygons in all layers are labelled and fully attributed. All care has been taken to ensure that all lines intersect at nodes (where applicable), no duplicate lines exist and all polygons are closed with no duplicate labels. Geological faults exist as dangling lines (overshoots) in polygon layers. Completeness: Data and basic descriptive attributes are complete (e.g., MAG_SYMB for polygon data; AGSO_CODE for line data). The geological interpretation is complete as at 8-MAY-2002. The authors reserve the right to make amendments according to new data or concepts. Contact information
Metadata informationMetadata date: 2013-03-08 Additional metadataMetadata reference XHTML: http://www.ga.gov.au/meta/ANZCW0703004741.html Metadata reference XML: http://www.ga.gov.au/meta/ANZCW0703004741.xml The online GIS contains the following datasets (all datasets presented in GDA94 datum, MGA53 projection) Vector data: Magint - polygon and line coverage of basement geology interpretation interpreted primarily from airborne magnetics and drillhole data. Maglin - line coverage of structural lines (eg: folds, trends, lineaments) interpreted from airborne magnetics. Basdpt - line coverage of depth-to-basement contours (see lineage) Minloc - major copper deposits extracted from GA's Minloc database Lakes - inland lakes Roads - major roads Towns - towns Raster data: tmi.bil - Total magnetic intensity, reduced to pole, hue, saturation, intensity image with a south-east sun angle illumination vd1_5.bil - TMI (rtp), 1.5 vertical derivative greyscale image gravity.bil - Bouguer gravity anomaly pseudocolour image with a sun angle (elevation 80 degrees, azimuth 315 degrees) illumination d_to_b.bil - Depth-to-basement pseudocolour image (see lineage) Authors:Direen, N.G. Lyons, P. |
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