Many countries around the world have carried out national-scale geochemical surveys, providing important information on the natural concentration of chemical elements and compounds in the near-surface regolith. Resultant data and information layers have been put to a multitude of uses: Identifying targets for mineral exploration; improving land-use management and environmental policy development; and providing information for studies into the health and well-being of humans, animals and plants. Between 2003 and 2007 several regional geochemical pilot surveys were conducted in Australia. These surveys have identified element concentrations that relate to soil acidity and salinity, reflect known areas of mineralisation, or are above or below national and international agricultural soils guidelines. In 2007, following on from the success of the pilot surveys, Geoscience Australia established Australia's first national geochemical survey. Working in collaboration with State and Territory geoscience agencies, ultra low-density sampling of catchment outlet (overbank) sediments from two depths (0-10 cm below surface and from a 10 cm interval at around 60-90 cm) has commenced. Samples are prepared and split into <2 mm and <75 mm fractions before both are analysed using a wide range of analytical techniques including XRF and ICP-MS. To date, 80% of samples have been collected and 50% of the total number of samples have been analysed. Ultimately the National Geochemical Survey of Australia project will rapidly and cost-effectively deliver a national geochemical atlas and a new dataset that will underpin positive outcomes in the exploration and mining, environmental, agricultural, forestry, recreational, and health and well-being sectors.

The Southern Thomson Orogen VTEMplus® AEM Survey was undertaken as part of Geoscience Australia's contribution to the Australian Academy of Science's UNCOVER initiative, adopted as part of the Australian Government's National Mineral Exploration Strategy. Survey planning was in conjunction with our State survey partners, the Geological Survey of New South Wales and the Geological Survey of Queensland. The aim of the survey was to demonstrate the application of the AEM technique as an under-cover mapping and exploration tool by generating new data and information regarding depth to basement (DTB) and cover character in the under-explored southern Thomson Orogen region. The ultimate goal of the Southern Thomson Project is to encourage industry investment in this poorly understood area to discover a new minerals province.

Poster for the Australian Earth Sciences Convention 2010.

National Geochemical Survey of Australia field training for the geoscience agencies of all States and the Northern Territory took place during 2007 and early 2008. The knowledge transfer mechanisms comprise a detailed National Geochemical Survey of Australia: Field Manual (GA Record 2007/08), this training presentation and several days of in-field sample collection under the guidance of NGSA staff.

This record reports on an AGSO/PIRSA/CRC LEME/Dominion Mining AEM Interpretation Workshop. The workshop focused on AEM data acquired over the Challenger Prospect in South Australia.

The Leonora 1:250,000 regolith landforms over compiosite radiometric image map illustrates the distribution of regolith materials and the landforms on which they occur, described using the RTMAP scheme developed by Geoscience Australia

The Mcfarlane 1:100,000 regolith-landform map illustrates the distribution of regolith materials and the landforms on which they occur, described using the RTMAP scheme developed by Geoscience Australia

The Merredin North 1:100,000 regolith-landform map illustrates the distribution of regolith materials and the landforms on which they occur, described using the Residual-Erosional-Depositional (RED) mapping scheme developed by the CSIRO Division of Exploration and Mining

The Menzies 1:250,000 regolith landforms over Landsat TM map illustrates the distribution of regolith materials and the landforms on which they occur, described using the RTMAP scheme developed by Geoscience Australia

The Mount Winnecke 1:100,000 regolith-landform map illustrates the distribution of regolith materials and the landforms on which they occur, described using the RTMAP scheme developed by Geoscience Australia