issue 91 Sept 2008

New surface geology dataset for South The Gawler Craton is located in the central part of the state Seamless digital surface geology of 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) (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 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 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). Australia’s thorium 10° resources in heavy mineral Darwin Alligator Rivers Rum Jungle South Alligator sand deposits could amount to Valley about 364 000 tonnes. Other Redbank Brockman Cummins Killi Killi Hills significant sources of thorium Range NT Mary Kathleen include the Nolans Bore deposit Nolans bore Yangibana Georgina Basin QLD Mud Tank Phosphorite deposits (with about 53 300 tonnes WA of thorium) in the Northern SA Mt. Painter Brisbane Mt. Weld 30° Territory and the Toongi zirconia Ponton Creek Billaroo Olympic Dam NSW Perth Radium Hill Toongi project (with about 35 000 Walloway Narraburra Sydney Adelaide complex tonnes of thorium) in New VIC Melbourne South Wales. 0 1000km Thorium occurs in nature TAS either within minerals or as a 120° 140° Hobart 08-3095-2 tetravalent ion. The large, highly Sources of Thorium 4+ Th-bearing uranium charged Th ion has a marked Vein type deposits Alkaline igneous Phosphorite deposits tendency to form complexes rock deposits Carbonatite deposits Rare-earth deposits with other ions in solution. The major ones of interest are Figure 1. Location of Australia’s thorium-bearing mineral deposits and occurrences excluding those related to heavy mineral sand deposits (Data is with chloride, fluoride, nitrate, from the Australian Mines Atlas). sulphate and carbonate ions.

Product News 4 issue 91 Sept 2008

Tiwi Island 10° geochemical surveys may also be Darwin used to help identify target areas at both regional and local scales. Australia has a wide variety of

NT deposits that contain thorium East coast but the geochemical processes QLD that lead to thorium-enrichment Eneabba WA North Cooljarloo Stradbroke Brisbane Island are poorly understood at SA Yoganup Eucla Basin 30° Ludlow present. More work is required Perth Tutunup NSW Murray to better understand the role of product news product Sydney Adelaide Basin Southwest thorium in the different styles VIC coast Melbourne of mineral deposits and to 0 1000km WIM 150 more comprehensively evaluate TAS 120° 140° Hobart 08-3095-1 Australia’s total identified

Thorium resources in Heavy Mineral Sand deposits thorium resources. Operating mine Mineral deposit Historic mine For more information Figure 2. Location of Australia’s mineral sand deposits including names of operating mines and selected historical mines. (Data is from the Australian phone Terry Mernagh on Mines Atlas). +61 2 6249 9460 email [email protected] The average abundance of thorium in the Earth’s crust is about 5.6 parts per million (ppm). The upper crust is enriched with an Related websites/articles average concentration of 10.5 ppm thorium, while the middle crust Onshore Energy Security has an average of 6.5 ppm, and the lower crust an average of 1.2 Program ppm. The most important thorium-bearing minerals are monazite, www.ga.gov.au/minerals/research/ thorianite, thorite, and thorogummite. Other minerals that contain oesp/index.jsp lesser amounts of thorium are allanite, bastnäsite, pyrochlore, A Review of the Geochemical xenotime, fluorapatite and zircon. Many of the thorium-bearing Processes Controlling the minerals are remarkably resistant to oxidation and tend to become Distribution of Thorium in the enriched in the oxidised zones of mineral deposits. Earth’s Crust and Australia’s Geophysical surveys involving radiometric, magnetic, and Thorium Resources by Terrence gravimetric techniques can all be applied to the search for thorium- P Mernagh and Yanis Miezitis bearing deposits. However, the lack of penetration of radiometric www.ga.gov.au/image_cache/ GA11421.pdf surveys limits the usefulness of this method in those areas of thick cover which are typical of many parts of Australia. In many places, Thorium Project the deep weathering of the Australian continent has destroyed www.ga.gov.au/minerals/research/ national/thorium/index.jsp primary rock lithologies, making recognition of mineralised areas exceptionally difficult. Consequently, stream sediment and other

Product News 5 issue 91 Sept 2008

New geophysical datasets released Datasets from five new geophysical surveys, which will be a valuable For more information tool in assessing the mineral potential of the respective survey areas, phone Murray Richardson on have been released since June 2008. +61 2 6249 9229 These include data from four new airborne magnetic and email murray.richardson@ radiometric surveys which cover Bass Strait and the offshore area off ga.gov.au northwest and southwest Tasmania and the Westmoreland region of Queensland. New gravity data covering the West Musgrave area of Related websites Western Australia have also been released. Geological Survey of Queensland The data for all surveys were acquired in surveys during 2007 and www.dme.qld.gov.au/mines/ product news product 2008, conducted and managed by Geoscience Australia on behalf of about_us.cfm Mineral Resources Tasmania, the Geological Survey of Queensland and the Geological Survey of Western Australia. The northwest Tasmania Geological Survey of offshore airborne magnetic survey was funded by Geoscience Australia. Western Australia The data have been incorporated into the national geophysical www.doir.wa.gov.au databases. The point-located and gridded data for the surveys can be Mineral Resources Tasmania obtained free online using the GADDS download facility. www.mrt.tas.gov.au

Table 1. Details of the gravity survey. Survey Survey type Date of 1:250 000 map Station Stations Contractor aquisition sheets spacing, orientation West Gravity May – June Bentley (pt), 2.5 x 2.5 km 4001 Daishsat Musgrave 2008 Scott (pt), east – west Geodetic (WA) Talbot (pt), Surveyors Cooper (pt)

Table 2. Details of the airborne surveys. Survey Survey type Date 1:250 000 map Line spacing/ Line km Contractor sheets terrain clearance/ orientation Bass Strait Magnetic Jan – Mar NA 800 m 70 856 Thomson (Tas) 2008 90 m Aviation east – west NW Tasmania Magnetic Jan – Apr NA 800 m 43 824 Fugro Offshore 2008 90 m Airborne east – west Surveys SW Tasmania Magnetic Jan – Apr NA 800 m 26 554 Fugro Offshore 2008 90 m Airborne east – west Surveys Westmoreland Magnetic, Sep – Dec Mornington (pt), 400 m 60 547 Fugro (Qld) Radiometric, 2007 Cape Van Dieman 60 m Airborne Elevation (pt), north – south Surveys Westmoreland (pt), Burketown (pt)

Product News 6 issue 91 Sept 2008

New NATMAP Digital Maps widen appeal Geoscience Australia has recently released NATMAP Digital Maps 2008 featuring a seamless map which covers the whole of Australia at 1:250 000 scale. This new version of the flagship digital mapping product includes a number of updated maps and a new satellite image of Australia. The operating software has been revised to improve its utility. Users can now compare a map with a satellite image of the same area using a new split window tool, or place one map over another with a

product news product transparency slide tool. The placename search facility, which is based on the Gazetteer of Australia, has also been updated. NATMAP Digital Maps 2008 has a wide variety of professional, emergency management and recreational uses including: • real-time navigation with global positioning systems (GPS) • route and adventure planning • providing backdrops for geographic information systems (GIS), where information is overlaid and analysed (such as emergency response planning) • map-based presentations • a convenient and compact storage of maps. Since the 1:250 000 scale topographic Raster data was included in the Office of Spatial Data Management’s Spatial Data Schedule in late 2005, the conditions for commercialisation of the product have For more information been relaxed. Consequently, the licence conditions for NATMAP phone Geoscience Australia Digital Maps 2008 have been clarified to remove any confusion Sales Centre on regarding the increased commercialisation potential of the data. Freecall 1800 800 173 However, some of the other data sets included as well as the Viewing (in Australia) or software remain proprietary and are not for commercial exploitation. +61 2 6249 9966 Though the previous edition of the NATMAP Raster 1:250 000 email [email protected] scale digital maps was available in two versions, the new version is equivalent in resolution quality to the previous ‘Premium’ version and the price has been reduced to $99.00. NATMAP Digital Maps 2008 is supplied on two DVDs and contains all the software needed to use the maps.

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