ISSUE 91 Sept 2008 New surface geology dataset for South Australia The Gawler Craton is located in the central part of the state Seamless digital surface geology of South Australia at 1:1 million scale and hosts several important is now available from Geoscience Australia. The dataset was primarily mineral deposits including iron compiled from 1:250 000 scale digital geology maps covering the oxide-copper-gold deposits at state and recent mapping by the Department of Primary Industries Olympic Dam and Prominent and Resources, South Australia. It is edge-matched to previously Hill, historic copper production released datasets of the geology of the eastern states and the Northern from Moonta –Wallaroo, gold Territory and includes a consistent nation-wide classification of at Challenger, and iron deposits regolith materials. in the Middleback Ranges The surface geology of South Australia is dominated by regolith west of Whyalla. The world’s product news product including sand plains, dunes, lake sediments, and colluvium around largest uranium deposit occurs prominent topography. Exposed bedrock is intermittently and widely at Olympic Dam in the eastern distributed with the intervening regions often covered with only a Gawler Craton. Uranium was thin regolith veneer. This bedrock is of diverse age, ranging from also mined at Radium Hill and recent Cainozoic sediments, to Archaean gneiss and greenstone in Mount Painter in the Palaeo- to the Gawler Craton. Mesoproterozoic Curnamona Craton located in the central 136° 138° 140° eastern part of the state, and 30° is currently extracted from Mt Painter (U, REE) Cainozoic sediments at the Beverley (U) Olympic Dam nearby Beverley Deposit. There (Cu, U, Au, Ag) Beltana (Zn, Pb) Ediacara has been historic production of (Pb, Ag, Cu) Blinman (Cu) copper and other base metals from many deposits throughout Mt Gunson (Cu, (Ag, Co)) the Neoproterozoic to Cambrian Adelaide Fold Belt and adjacent SOUTH AUSTRALIA 32° Cambrian Kanmantoo Fold Belt. Waukaringa (Au) Teetulpa (Au) The new digital data puts Port Augusta these mineral deposits and many others in their regional geological Whyalla context. It also supports the Port Pirie development of regional exploration models which are Burra (Cu) necessary to effectively explore Wallaroo (Cu, Au) Moonta (Cu, Au) 34° regions under cover. The digital geology data are intended for use at 1:1 million scale and have a 08-3103-1 0 250 km spatial accuracy of approximately one kilometre. Geological NT Mineral deposit (Pb) unit attributes include the QLD Mineral deposit (U) WA stratigraphic name, the Australian SA Mineral deposit (Cu) NSW Stratigraphic Unit Database VIC Mineral deposit (Au) TAS number, lithological description, and maximum and minimum Figure 1. Geology of the Flinders Ranges region, north of Adelaide. ages. Summary attributes Product News 1 ISSUE 91 Sept 2008 including lithology group and lithology type provide additional For more information flexibility for analysing the geological polygon data. Outcropping and phone Alan Whitaker on selected buried faults are also represented in the dataset. +61 2 6249 9702 The data are available as a free download, or on CD which can be email [email protected] purchased through the Geoscience Australia website for $99.00. To order copies of the CDs Related articles/websites phone Freecall 1800 800 173 (in Australia) or Surface geology of South Australia, 1:1 million scale (free download) +61 2 6249 9966 www.ga.gov.au/products/ email [email protected] Geoscience Australia Sales Centre (for purchase on CD) product news product www.ga.gov.au/oracle/agsocat/ Revealing Proterozoic mafic-ultramafic magmatism in Australia Geoscience Australia in collaboration with the State and Territory group element deposits in other geological surveys has recently released a detailed web-based map continents, such as ~2440 Ma that shows the location, age, and correlations of Proterozoic mafic- Penikat in Finland, ~1918 Ma ultramafic igneous rocks across the Australian continent. The new Raglan, ~1880 Ma Thompson, colour map Australian Proterozoic mafic-ultramafic magmatic events and ~1850 Ma Sudbury in consists of two sheets which are available in pdf and jpeg formats Canada, ~1403 Ma Kabanga in through the Geoscience Australia website. Tanzania, and ~827 Ma Jinchuan A 1:5 000 000 scale map showing the continental distribution in China. of 30 magmatic events that range from the Early Palaeoproterozoic Sheet 2 also includes two (~2455 million years (Ma), ME 1) to the Early Cambrian (~520 maps at 1:10 000 000 scale. Ma, ME 30) is the main feature of Sheet 1. The newly-defined The first map shows the locations magmatic event series (ME 1–ME 30) is based on several hundred of Australian nickel-copper- age measurements, over 90 per cent of which are derived from recent chromium-vanadium-titanium Uranium-Lead (U-Pb) dating of zircon and baddeleyite. and platinum-group element Solid geology digital maps with state/territory and regional coverages mineral deposits and occurrences were synthesised to produce a national presentation of mafic-ultramafic overlain on a composite of rock units, and regional rock packages that include coeval mafic- Proterozoic and Archaean mafic- ultramafic igneous rock components. Colour-coding of rock units by ultramafic rock units. The second their age of magmatism provides a visual cue to the spatial and temporal map shows the geographic extent correlations of magmatic units at both province and continental scale. of five magmatic events which Their relationship to the evolution of the continent is shown with an are designated Large Igneous overlay of the Australian Crustal Elements dataset. The detail in the Provinces which are characterised new map extends to isolated occurrences of dated magmatic units and by exceptionally large volumes of a commentary describing relevant rock relationships. mafic-dominated magma emplaced The second sheet includes a large format Time–Space–Event Chart over short geological periods of a which shows the presence and correlation of the 30 magmatic events few million years or less. across 28 Australian crustal provinces. Those events known to be The new national map is mineralised in Australia are highlighted, and six of the magmatic the final component of the events are shown to be coeval with major nickel-copper ± platinum- Proterozoic magmatic event Product News 2 ISSUE 91 Sept 2008 map series. It revises and supersedes the earlier maps of Western For more information Australia and Northern Territory–South Australia. The geological phone Dean Hoatson on and geochronological basis of the map series is summarised in an +61 2 6249 9593 accompanying Geoscience Australia Record 2008/15 Guide to email [email protected] using the 1:5 000 000 map of Australian Proterozoic mafic-ultramafic magmatic events by DM Hoatson, JC Claoué-Long, & S Jaireth. Related websites/articles The Record includes individual time-slice maps of Australia for each Australian Proterozoic Mafic- of the 30 Proterozoic magmatic events. Ultramafic Magmatic Events Map (Sheet 1 of 2) The new national map focuses attention on the extent and volume of certain magmatic systems, and associations with mineralisation. www.ga.gov.au/image_cache/ product news product GA11507.pdf The locations of mafic-ultramafic rock units, correlations across the www.ga.gov.au/image_cache/ continent, and the relationship of magmatism to the evolving crustal GA11511.jpg structure of the continent, are all prominent. The new map and Australian Proterozoic Mafic- Record will be of interest to explorers searching for nickel, platinum- Ultramafic Magmatic Events group elements, chromium, titanium, and vanadium, as well as Map (Sheet 2 of 2) providing fundamental resources for understanding the dynamic evolution of the Australian continent. www.ga.gov.au/image_cache/ GA11506.pdf www.ga.gov.au/image_cache/ GA11510.jpg Part 1. Proterozoic Mafic- Ultramafic Magmatic Events Map: Western Australia www.ga.gov.au/image_cache/ GA8798.pdf www.ga.gov.au/image_cache/ GA8797.jpg Part 2. Proterozoic Mafic- Ultramafic Magmatic Events Map: Northern Territory and South Australia www.ga.gov.au/image_cache/ GA10636.pdf www.ga.gov.au/image_cache/ GA10645.jpg AusGeo News 84: New map for nickel explorers www.ga.gov.au/ausgeonews/ ausgeonews200612/productnews. jsp#product2 AusGeo News 87: New map for nickel and platinum explorers www.ga.gov.au/ausgeonews/ Figure 1. Part of the new 1:5 000 000 scale Australian Proterozoic ausgeonews200709/productnews. mafic-ultramafic magmatic events map. jsp#product1 Product News 3 ISSUE 91 Sept 2008 Review of Australia’s thorium resources This review provides an enhanced understanding of geochemical currently developing a thorium- processes controlling the distribution of thorium in the Earth’s crust fuelled Advanced Heavy Water and the status and distribution of Australia’s thorium resources. It Reactor. is an output from Geoscience Australia’s Onshore Energy Security There has been no widespread Program (OESP) and can be downloaded through Geoscience exploration for thorium in Australia’s website. The OESP is delivering pre-competitive data Australia. However, thorium is packages and scientifically-based assessments to attract investment in known to be widely distributed exploration for onshore energy resources such as oil, gas, uranium, across Australia in a number product news product thorium and geothermal energy. of different geological settings Thorium can be used as a nuclear fuel, through breeding to (figure 1). Australia contains uranium (233U). Several reactor concepts based on thorium fuel cycles about 19 per cent of the world’s are under consideration, but much development work would be identified thorium resources. required before the thorium fuel cycles can be commercialised. At Most of them are held in the present thorium fuels are used to varying degrees in some research monazite component of heavy reactors in India and Russia. Tests are being undertaken in Russia on mineral sand deposits that are the use of thorium fuel in conventional nuclear reactors and India is mined for their ilmenite, rutile, leucoxene and zircon content (figure 2).