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  • Map produced for the Australian Government Solicitor in March 2009 showing the Torres Strait Regional Claim (Q6040 of 2001) as mofidied and the Great Barrier Reef Marine Park. For confidental/internal use by AGS and not for general release.

  • This address was presented at the 2009 Australian Nickel Conference held in Perth, 14-15th October 2009. Geoscience Australia has recently released two web-based map sheets (at: http://www.ga.gov.au/resources/maps/minerals/index.jsp) that show the continental extent and age relationships of Archean mafic and ultramafic rocks and associated mineral deposits throughout Australia. The maps were produced in close collaboration with the State and Northern Territory geological surveys. The Archean eon (~4000 million years to 2500 million years) represents an early part of Earth's history that is noteworthy for the earliest forms of life and the widespread occurrence of unusual olivine-rich ultramafic rocks called komatiites which contain world-class deposits of nickel sulphides. The major objective of this presentation is to promote the applications of the National map, which should be of interest to those explorers searching for nickel, platinum-group elements (PGEs), chromium, titanium, and vanadium. The new map sheets, when used in association with the `Australian Proterozoic Mafic-Ultramafic Magmatic Events' map published in 2008 (GeoCat 66114; GA Record 2008/15), summarise the temporal and spatial evolution of Precambrian mafic-ultramafic magmatism in Australia. These maps provide a national framework for investigating under-explored and potentially mineralised environments, and assessing the role of mafic-ultramafic magmatism in the development of the Australian continent.

  • Uranium-rich igneous rocks are recognised as an important source of metals in uranium mineral systems. Magmatic-related uranium mineralisation may be orthomagmatic in origin, forming via favourable igneous processes, or may result from the exsolution of uranium-rich fluids from particular magmas. Additionally, it is recognised that igneous rocks also may contribute directly to basin-related uranium mineral systems as a metal source. Thus, mapping of the distribution of uranium in igneous rocks has the potential to highlight prospective regions for uranium mineralisation at a macro-scale. Geoscience Australia has produced a series of three digital maps showing the uranium content of igneous rocks across Australia, drawing together geochemical and geological datasets from disparate open file sources. Map 1 shows the uranium concentration in whole rock geochemical analyses plotted as point data on a background of igneous rock type, which itself is derived from Geoscience Australia's 1:1 000 000 national surface geology map. Map 2 integrates these datasets, and shows the average uranium content of all intersecting geochemical data point for outcropping individual igneous rock units. In Map 3, a similar approach is employed in mapping the average uranium content of igneous rocks occurring under cover, using interpreted solid geology coverages. Combined, these maps provide a comprehensive picture of the province-scale trends in igneous uranium content across the continent. Using an applied knowledge of processes leading to uranium concentration in magmatic systems, igneous rocks exhibiting a favourable combination of factors are able to be identified for further analysis of prospectivity for uranium mineral systems.

  • This is a combined metamorphic and strain map of the Eastern Yilgarn Craton. Inset maps of different phases of metamorphism are also shown. <p>Related material<a href="https://www.ga.gov.au/products/servlet/controller?event=GEOCAT_DETAILS&catno=68806">Metamorphic Evolution and Integrated Terrane Analysis of the Eastern Yilgarn Craton: Rationale, Methods, Outcomes and Interpretation</a> - Geoscience Australia Record 2009/023.</p>

  • The purpose of this review is to assess the existing published information relating to groundwater quality in Australia and New Zealand.

  • This year, the Commonwealth Government is offering 6 large exploration areas in the frontier Bight Basin. The release areas (Figure 1) are situated in the central Great Australian Bight off southern Australia, approximately 415 to 655 km west of Port Lincoln, South Australia and 250 to 530 km southwest of Ceduna, South Australia. The areas are located within the Ceduna Sub-basin, in the eastern part of the Bight Basin, in water depths ranging from 130 to 4600 m. At present, no permits are held in this part of the basin. The release areas range in size from 85 to 90 graticular blocks (6000 to 6395 km2), and bids for all 6 areas close on 29 April 2010. Most exploration drilling in the Bight Basin has focused on the margins of the Ceduna Sub-basin and the Duntroon Sub-basin to the southeast of the current release areas. Gnarlyknots 1A, drilled by Woodside Energy and partners in 2003, is the only well to have attempted to test the thick, prospective Ceduna Sub-basin succession away from the margins of the sub-basin. Unfortunately the well was not an exploration success, as it had to be abandoned due to deteriorating weather and ocean conditions without reaching all planned target horizons. In 2007, Geoscience Australia conducted a marine sampling survey in the Bight Basin that dredged a suite of organic-rich rocks of Cenomanian-Turonian age from the northwestern exposed edge of the Ceduna Sub-basin. Geochemical analyses have characterised these samples as world-class, oil-prone, marine potential source rocks. Seismic interpretation indicates that this interval can be mapped throughout most of the basin and is mature for oil and gas generation across much of the Ceduna Sub-basin.

  • Map showing Australia's Maritime Jurisdiction in the Timor Sea on a blue imagery background made from data collected from research vessels and/or derived from satellite imagery. For internal use as at 27 sept 2009.

  • Annual update of map backing the combined GA/RET NAPE Conference brochure.

  • Remotely sensed imagery has been used extensively in geomorphology since the availability of early Landsat data. Since that time, there has been a steady increase in the range of sensors offering data with increased spatial and spectral resolutions, from both government and commercial satellites. This has been augmented with an increase in the amount and range of airborne surveys carried out. Since 2000, digital elevation models have become widely available through the application of interferometric synthetic aperture radar, photogrammetry and laser altimetry (specifically LiDAR) with extensive uptake by geomorphologists. In addition, hyperspectral imaging, radiometrics and electromagentics have been made more accessible, whilst there has been increased use of close-range (<200 m) imaging techniques for very high resolution imaging. This paper reviews the primary sources for DEMs from satellite and airborne platforms, as well as briefly reviewing more traditional multi-spectral scanners, and radiometric and electromagnetic systems. Examples of the applications of these techniques are summarised and presented within the context of landscape pattern recognition and modelling. Finally, the wider issues of access to geographic information and data distribution are discussed.

  • Conceptual MAR targets in the Broken Hill region were identified in previous investigations (Lewis et al., 2008; Lawrie et al., 2009a). In the BHMAR Phase 2 study, the project team is required to make recommendations on the presence and suitability of potential MAR sites with an 80% confidence level. While this will be attempted through a combination of AEM, borehole analysis and seismic reflection data acquisition, AEM is the prime dataset required to map the aquifer targets in 3D.