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  • The Herberton/Mount Garnet area is situated in north Queensland, southwest of Cairns (Fig. 1). It is bounded by latitudes 17°15'S and 17°45'S, and by longitudes 145°00'E and 145°30'E, and comprises 2885 sq km. The area is covered by the Herberton and Mount Garnet 1-mile Military map sheets, and lies within the Atherton 1:250,000 Sheet area. Almost the whole of the productive part of the Herberton Tinfield* is covered by the two 1-mile map sheets.

  • The Paterson AEM survey was flown over the Paterson Orogen, the eastern Pilbara Craton and the on-lapping Officer and Canning Basins in NW Western Australia between September 2007 and October 2008 as part of the Commonwealth Government's Onshore Energy Security Program. The survey was designed to provide pre-competitive data for enhancing uranium and other mineral exploration. Flight lines were at a variety of spacings from 6, 2 and 1 km to 200 m targeting known deposits and other covered highly prospective rocks for a total area of 45,330 km2. The survey data has afforded new insights into the Paleozoic paleotopography of the region which is blanketed by regolith including Phanerozoic sediments including Permian glaciogene, Mesozoic and Cenozoic sediments. These insights have major implications for mineral prospectivity.

  • From 1995 to 2000 information from the federal and state governments was compiled for Comprehensive Regional Assessments (CRA), which formed the basis for Regional Forest Agreements (RFA) that identified areas for conservation to meet targets agreed by the Commonwealth Government with the United Nations. These 3 CDs were created as part of GA's contribution to the Eden, NSW CRA. CD1 contains original and final versions of all data coverages and shapefiles used in the project, Published Graphics files in ArcInfo (.gra), postscript (.ps) and Web ready (.gif) formats, all Geophysical Images and Landsat data and final versions of documents provided for publishing. CD2 contains the DEFUNCT directories, data that has been modified or replaced in the final version. CD3 contains the INTEGRTN directory, integration data used for evaluating options.

  • Abstract The Palaeoproterozoic, from 2100 to 1800 Ma, is recognised as the third largest period of orogenic gold mineralization. In contrast to earlier Archean orogenic gold episodes which occur predominantly in greenstone terranes, supracrustal sedimentary rocks became increasingly important as hosts in the Palaeoproterozoic. Unusually iron-rich 1840 Ma marine mudstones in the Tanami region host one world class gold deposit and many other gold deposits. Fluid-rock modelling at 350°C suggest a strong correlation between gold grade and these iron-rich, fine-grained sedimentary rocks and suggest that gold may precipitate in the iron-rich sediments in the first stage of mineralization, before remobilization of the gold further enhances the grade of the deposit. New regional stratigraphic correlations for similar iron-rich rocks to those in the Tanami region are suggested with ~1860 Ma gold-bearing stratigraphy in the Pine Creek region and potentially with ~1860 Ma host rocks in the Tennant region. These Northern Australian Palaeoproterozoic iron-rich sedimentary rocks could be linked globally to similar aged iron-rich and gold-bearing sedimentary rocks in Homestake, U.S., Ghana, West Africa and elsewhere. From about 2400 to 1800 Ma the Palaeoproterozoic is also marked by the occurrence of mainly Superior-style BIF's, which are attributed to the progressive oxygenation of the deep oceans resulting in the global scrubbing of iron from the oceans. The high iron concentrations noted in pre-1800 Ma marine sediments in Northern Australia could also be related to this same process and help explain the anomalous concentration of orogenic Au deposits from 2100 to 1800 Ma.

  • Legacy product - no abstract available

  • In addition to typical seafloor VHMS deposits, the ~3240 Ma Panorama district contains contemporaneous greisen- and vein-hosted Mo-Cu-Zn-Sn occurrences that hosted by the Strelley granite complex, which drove VHMS circulation. High-temperature alteration zones in volcanic rocks underlying the VHMS deposits are dominated by quartz-chlorite±albite assemblages, with lesser low-temperature quartz-sericite±K-feldspar assemblages, typical of VHMS hydrothermal systems. Alteration assemblages associated with granite-hosted greisens and veins, which do not extend into the overlying volcanc pile, include quartz-topaz-muscovite-fluorite and quartz-muscovite(sericite)-chlorite-ankerite. Fluid inclusion and stable isotope data suggest that the greisens formed from high temperature (~590C), high salinity (38-56 wt % NaCl equiv) fluids with high densities (>1.3 g/cm3) and high -18O (9.3±0.6-), which are compatible with magmatic fluids evolved from the Strelley granite complex. Fluids in the volcanic pile (including the VHMS ore-forming fluids) were of lower temperature (90-270C), lower salinity (5.0-11.2 wt % NaCl equiv), with lower densities (0.88-1.01 g/cm3) and lower -18O (-0.8±2.6), compatible with evolved Paleoarchean seawater. Fluids that formed the quartz-chalcopyrite-sphalerite-cassiterite veins, which are present within the upper granite complex, were intermediate in temperature and isotopic composition (T = 240-315C; -18O = 4.3±1.5-) and are interpreted to indicate mixing between the two end-member fluids. Evidence of mixing between evolved seawater and magmatic-hydrothermal fluid in the granite complex, along with a lack of evidence for a magmatic component in fluids from the volcanic pile, suggest partitioning of magmatic-hydrothermal from evolved seawater hydrothermal systems in the Panorama VHMS system, interpreted as a consequence swamping of the system by evolved seawater or density contrasts.

  • Globally supracrustal sedimentary rocks are known to preferentially precipitate gold between 2400 Ma and 1800 Ma (Goldfarb et al. 2001). The Palaeoproterozoic Tanami and Pine Creek regions of Northern Australia host one world-class gold deposit and many other gold deposits in anomalously iron-rich marine mudstones (Figure 1). New fluid-rock modelling at temperatures between 275 - 350C suggest a strong correlation between gold grade and these Palaeoproterozoic iron-rich, fine-grained sedimentary rocks.

  • Assessment of mineral potential in the Regional Forest Agreement Areas (RFAs) required collating mineral potential tract maps of individual deposit styles to produce composite, cumulative and weighted composite and cumulative maps. To achieve that an Avenue-script based ArcView extension was created to combine grids of mineral potential tract maps. The grids were combined to generate maps which showed either the highest (weighted or non-weighted) or cumulated (weighted or non-weighted) values. Resources and Advice Decision Support System (RADSS) combines features of the ArcView extension used in mineral potential assessments in RFAs and ASSESS. It is an ArcView extension with a 'Wizard'-like main dialog that leads the user through the process of creating an output. The system has the capacity to combine GIS-layers (raster and vector) to produce various mineral potential and other suitability maps.

  • DRAFT Australia's Resources Supporting Economic Growth in the Nation and the Region Paul J Kay Geoscience Australia A new book on Australia's geology viewed through the lens of human activity has been prepared by Geoscience Australia for the 34th International Geological Congress (IGC). Geological factors influencing the nation's recent economic development make up one chapter of the IGC book. Australia's long geological history, fringing passive margins, limited recent deformation and overall landscape stability has formed and preserved a vast quantity of high quality bulk commodity resources. The nation's educated workforce, system of government and legal framework has provided a sound, stable foundation allowing the geological legacy to be utilised through a large export industry for societal and national benefit. The bulk resources of coal, iron, aluminium and liquefied natural gas (LNG) account for more than 50 percent of Australia's export earnings, sustaining the nation's economic success and the lifestyle of the Australian people. Mining has been a cornerstone of the Australian economy since the 19th century gold rushes and importance the resources sector has increased markedly since the mid 20th century, largely a consequence of accelerating export income from the bulk commodities. The industrialisation of Asia has provided the demand, driving infrastructure investment in remote regions of Australia. Advances in technology combined with massive economies of scale and sound public policy have enabled access to the resource and helped to satiate the growing regional market. Responding to changes in the existing status quo, be they trade or societal, will require ongoing interactions between the geosciences and other disciplines to maintain and improve Australia's standard of living.