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  • Predictive mineral discovery is concerned with the application of a whole of system process understanding to mineral exploration as opposed to an empirical deposit type approach. A mineral system process understanding can be derived from a consideration of five key questions, namely what is/are the: 1) geodynamic setting; 2) architecture; 3) sources and reservoirs; 4) drivers and pathways, and; 5) depositional mechanisms. The answers to these questions result in the identification of critical processes necessary for the function of a mineral system within a particular terrane, and permit the development of a targeting model. In this contribution we identify district scale critical orogenic gold mineral system processes for the late Archaean eastern Yilgarn Craton of Western Australia. During the geodynamic history of a terrane the critical processes which result in mineralisation change with time resulting in variations in mineralisation style. Proxies for critical processes have been mapped in an integrated GIS and are termed mappable mineral system process proxies (or MMSPP). In recognition of this, three separate time slices and a geochemical theme were analysed. Each MMSPP is given a weighting factor (WF) which reflects the spatial accuracy/coverage of the data and process criticality. For each theme/time-slice, a separate prospectivity map was created by summing the overlay or union of the spatial extent of each MMSPP, and adding the WF. A final target or prospectivity map was generated by a union of the four theme/time-slice prospectivity maps, and is tested against the known major deposits. The map 'discovered' the main gold camps and accounts for over 75% of the known gold in 5% of the area. This test verifies the process-based understanding and the appropriate mapping of the critical proxies. A further outcome from the map was the identification of a number of new target areas not known for significant gold mineralisation in what otherwise is thought to represent a mature terrane for gold exploration. The approach taken here has been to consider the Late Archaean gold deposits as a holistic system. Despite the recurring areas of uncertainty, this systems view has resulted in new findings that have generic applications to other mineral systems.

  • A new continental-scale geochemical atlas and dataset for Australia were officially released into the public domain at the end of June 2011. The National Geochemical Survey of Australia (NGSA) project, which started in 2007 under the Australian Government's Onshore Energy Security Program at Geoscience Australia, aimed at filling a huge knowledge gap relating to the geochemical composition of surface and near-surface materials in Australia. Better understanding the concentration levels and spatial distributions of chemical elements in the regolith has profound implications for energy and mineral exploration, as well as for natural resource management. In this world first project, a uniform regolith medium was sampled at an ultra-low density over nearly the entire continent, and subsamples from two depths and two grain-size fractions were analysed using up to three different (total, strong and weak) chemical digestions. This procedure yielded an internally consistent and comprehensive geochemical dataset for 68 chemical elements (plus additional bulk properties). From its inception, the emphasis of the project has been on quality control and documentation of procedures and results, and this has resulted in eight reports (including an atlas containing over 500 geochemical maps) and a large geochemical dataset representing the significant deliverables of this ambitious and innovative project. The NGSA project was carried out in collaboration with the geoscience agencies from every State and the Northern Territory under National Geoscience Agreements. .../...

  • Joint Release of the National ASTER geoscience maps at IGC The ASTER (Advanced Spaceborne Thermal Emission and Reflectance Radiometer) Geoscience Maps are the first public, web-accessible, continent-scale product release from the ASTER Global Mapping data archive. The collaborative Australian ASTER Initiative represents a successful multi-agency endeavour, led by the Western Australian Centre of Excellence for 3D Mineral Mapping (C3DMM) at CSIRO, Geoscience Australia and the State and Territory government geological surveys of Australia, along with other national and international collaborators. National ASTER geoscience map These geoscience maps are released in GIS format as 1:1M map-sheet tiles, from 3,000 ASTER scenes of 60x60km. Each scene was cross-calibrated and validated using independent Hyperion satellite imagery. The new ASTER geoscience products range in their application from local to continental scales, and their uses include mapping of soils for agricultural and environmental management, such as estimating soil loss, dust management and water catchment modelling. They will also be useful for resource exploration, showing host rock, alteration and regolith mineralogy and providing new mineral information at high spatial resolution (30m pixel). This information is not currently available from other pre-competitive geoscience data.

  • ABSTRACT: Building on method developments achieved during a series of precursor pilot projects, the National Geochemical Survey of Australia (NGSA) project targets catchment outlet (overbank) sediments as a uniform sampling medium. These transported, fine-grained materials are collected (from a shallow and a deeper level) near the lowest point of 1390 catchments, which cover 91% of the country. Dry and moist Munsell® colour, soil pH and electrical conductivity and pH of 1:5 (soil:water) slurries are recorded and laser particle size analysis and infrared spectroscopy are performed. The dried samples are sieved into two grain-size fractions (<2 mm and <75 mm) that are analysed by x-ray fluorescence (XRF) and inductively-coupled mass spectrometry (ICP-MS) (multi-element, total analyses), by ICP-MS after aqua regia digestion (multi-element, including low level gold), and specialised methods for platinum group elements, fluorine and selenium. At the time of writing, 78% of the samples have been collected and most analyses are completed for the first 25% of samples. The project is due for completion in June 2011.

  • Australia's Identified Mineral Resources is an annual nation-wide assessment of Australia's ore reserves and mineral resources.

  • Australia's Identified Mineral Resources is an annual nation-wide assessment of Australia's ore reserves and mineral resources.

  • Australia's Identified Mineral Resources is an annual nation-wide assessment of Australia's ore reserves and mineral resources.

  • Australia's Identified Mineral Resources is an annual nation-wide assessment of Australia's ore reserves and mineral resources.