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The advantages of integrating datasets in the search for mineralization in areas characterized by subdued relief, extensive areas of transported regolith, and a semi-arid climate, are shown using direct observations (e.g. bedrock and regolith mapping, regolith geochemistry) and remotely-sensed data (e.g. airborne magnetics, gravity, Landsat TM) over a 48 000 km 2 area in central Western Australia. In this area, Archaean granite and greenstones are unconformably overlain by a 5 km-thick sequence of Paleoproterozoic (c. < 1840 Ma) and Mesoproterozoic (c. 1200 Ma) sedimentary rocks, both of which are intruded by c. 1070-1400 Ma dolerites. Known mineralization comprises small lode gold deposits hosted by Archaean greenstones (e.g. <0.25 Mt @ 4 gt 1 ) and MVT-type mineralization in Paleoproterozoic stromatolitic carbonate rocks. Outcrop is sparse, with transported regolith covering about 85% of the area.Regolith sampling and subsequent multi-element analysis has been carried out on a 4 4 km sampling grid over the whole area, and simultaneous measurement of gravity at each regolith sampling site has been carried out in the eastern two-thirds of the area. Integration of these data with existing gravity data, airborne magnetics, Landsat TM, and detailed bedrock mapping of selected exposures has identified seven potential areas of mineralization, including structurally controlled gold and base metal deposits associated with regional deformation, stratiform MnO and base metal mineralization, and magmatic sulfide mineralization associated with the intrusion of thick mafic sill complexes. Although regional regolith chemistry is capable of identifying all seven areas of mineralization, detailed bedrock mapping and geophysics are essential to understand the style of mineralization and to put the mineralization into a tectonic framework. The preferred tectonic model comprises the deposition of siliciclastic and chemical sedimentary rocks on a passive continental margin, followed by regional deformation, and emplacement of high-level mafic sills and dykes.

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The seismic method has been thriving in the oil and gas industry for decades. Technological progress in acquisition, processing and interpretation have made it practically the only geophysical method used for petroleum exploration. Unfortunately, gravity, as a pioneering geophysical method appears to have been completely forgotten in Australia’s oil and gas industry. Most of the gravity data in Australia were collected in the 1960s and 1970s. Only government agencies and a few exploration companies have conducted gravity surveys in petroleum basins since that time. Australia’s mostly flat terrain, economical aspects of the gravity method such as low cost and the ability to cover vast underexplored onshore basins in the country, all seem to be positive factors indicating that this method should be commonly used as a part of petroleum exploration. Given the petroleum industry is currently trying hard to make exploration more economically effective, this may be an opportunity to revive the gravity method in petroleum exploration.

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