2nd edition Available as a GA Library resource.

Displays the coverage of publicly available digital gamma-ray spectrometric data. The map legend is coloured according to the line spacing of the survey with broader line spacings (lower resolution surveys) displayed in shades of blue. Closer line spacings (higher resolution surveys are displayed in red, purple and coral.

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.

Compiled from Original 100k data Arbitrary Pub Year set at 1965 for this product to enable web release

Geoscience Australia (GA) is a leading promoter of airborne electromagnetic (AEM) surveying for regional mapping of cover thickness, under-cover basement geology and sedimentary basin architecture. Geoscience Australia flew three regional AEM surveys during the 2006-2011 Onshore Energy Security Program (OESP): Paterson (Western Australia, 2007-08); Pine Creek-Kombolgie (Northern Territory, 2009); and Frome (South Australia, 2010). Results from these surveys have produced a new understanding of the architecture of critical mineral system elements and mineral prospectivity (for a wide range of commodities) of these regions in the regolith, sedimentary basins and buried basement terrains. The OESP AEM survey data were processed using the National Computational Infrastructure (NCI) at the Australian National University to produce GIS-ready interpretation products and GOCADTM objects. The AEM data link scattered stratigraphic boreholes and seismic lines and allow the extrapolation of these 1D and 2D objects into 3D, often to explorable depths (~ 500 m). These data sets can then be combined with solid geology interpretations to allow researchers in government, industry and academia to build more reliable 3D models of basement geology, unconformities, the depth of weathering, structures, sedimentary facies changes and basin architecture across a wide area. The AEM data can also be used to describe the depth of weathering on unconformity surfaces that affects the geophysical signatures of underlying rocks. A number of 3D models developed at GA interpret the under-cover geology of cratons and mobile zones, the unconformity surfaces between these and the overlying sedimentary basins, and the architecture of those basins. These models are constructed primarily from AEM data using stratigraphic borehole control and show how AEM data can be used to map the cross-over area between surface geological mapping, stratigraphic drilling and seismic reflection mapping. These models can be used by minerals explorers to more confidently explore in areas of shallow to moderate sedimentary basin cover by providing more accurate cover thickness and depth to target information. The impacts of the three OESP AEM surveys are now beginning to be recognised. The success of the Paterson AEM Survey has led to the Geological Survey of Western Australia announcing a series of OESP-style regional AEM surveys for the future, the first of which (the Capricorn Orogen AEM Survey) completed acquisition in January 2014. Several new discoveries have been attributed to the OESP AEM data sets including deposits at Yeneena (copper) and Beadell (copper-lead-zinc) in the Paterson region, Thunderball (uranium) in the Pine Creek region and Farina (copper) in the Frome region. New tenements for uranium, copper and gold have also been announced on the results of these surveys. Regional AEM is now being applied in a joint State and Commonwealth Government initiative between GA, the Geological Survey of Queensland and the Geological Survey of New South Wales to assess the geology and prospectivity of the Southern Thomson Orogen around Hungerford and Eulo. These data will be used to map the depth of the unconformity between the Thomson Orogen rocks and overlying sedimentary basins, interpret the nature of covered basement rocks and provide more reliable cover thickness and depth to target information for explorers in this frontier area.

No abstract available

Solid geology map of North eastern goldfields 1:500 000

An interpretation of the Mulgathing Complex, a late Archaean high grade metamorphic complex in the northwest of the Gawler Craton, host to the Challenger Au deposit. This interpretation is based on gravity, drillhole and airborne magnetic datasets, ground reconnaissance and published geological maps. This map presents an interpretation of basement geology based on ground reconnaissance,interrogation of drill-hole databases, and interpretation of airborne magnetics, gravity data, and previous geological mapping: Benbow, M.C., 1981, COOBER PEDY 1:250 000 Geological Series SH53-6; Daly, S.J., 1985, TARCOOLA 1:250 000 Geological Series SH53-10; Benbow, M.C., 1986, TALLARINGA 1:250 000 Geological Series SH53-5; Benbow, M.C. et al., 1995, BARTON 1:250 000 Geological Series SH53-9; Vitols, V., 1974, COOBER PEDY 1:250 000 Geological Series SH53-6(Preliminary Edition). All the above authors from the Office of Minerals and Energy Resources, South Australia (or predecessors). The boundaries of some mapped units were modified to be consistent with geophysical data or ground truthing. As the map area is essentially under cover, the interpretation is necessarily broad and many anomalies remain uninterpreted. Granulite facies metamorphism has demagnetised much of the Mulgathing Complex and lithological packages, known to exist, could not be distinguished or differentiated. Areas where Palaeozoic cover has attenuated potential fields are shown. Gravity data come from 3851 stations out of a combined database of the Gawler Craton compiled by N.G. Direen (AGSO, unpublished data). These data comprise Commonwealth, State, and open file company surveys. Gravity data were converted to Simple Bouguer Anomalies at an S.G. of 2.67, according to the method of Wellman et al. (1985, BMR Record 261). Geodetic data were converted onto WGS84 and projected to MGA53. An ERMapper grid was produced in Intrepid using a multi-pass, variable density minimum curvature technique with a final grid cell size of 200 m. Intermediate gridding parameters included a coarse cell size of 21 km and a 32 cell extrapolation radius.

The map of iron oxide copper-gold (IOCG) potential of the Gawler Craton, South Australia, shows the spatial distribution of key 'essential ingredients' of IOCG ore-forming systems. These 'ingredients' include: (a) rock units of the Gawler Range-Hiltaba Volcano-Plutonic Association, subdivided by supersuite; (b) faults/shear zones subdivided by interpreted age of youngest significant movement; (c) copper geochemistry (>200ppm), from drill holes intersecting crystalline basement (Mesoproterozoic and older); (d) hydrothermal alteration assemblages and zones, based on drill hole logging, potential-field interpretation, and inversion modelling of potential-field data; and (e) host sequence units considered important in localising IOCG alteration and mineralisation. Also shown are Nd isotopic data and the mineral isotopic ages of late Palaeoproterozoic to early Mesoproterozoic magmatism and hydrothermal minerals. Areas with the greatest number of 'essential ingredients' are considered to have the maximum potential for IOCG mineralisation. IOCG potential of the Gawler Craton is shown as domains with ranks from 1 to 4, with 1 being the highest rank. Notes detailing the sources of data and methods used in constructing the map are provided in a separate file available on the Geoscience Australia website.

The biological data used in this study was collected by Museum Victoria in an extensive survey of the fauna of Bass Strait between 1979 and 1983. Additional sediment sampling and swath mapping of parts of Bass Strait were undertaken on GA Survey 226 and Australian Hydrographic Office Survey HI339, in which Geoscience Australia personnel participated (GA Survey 233). Survey HI339 also collected underwater video footage. Biological material from a range of taxonomic groups was identified as a basis for identification and analysis of biological communities. The results indicate that Bass Strait supports a particularly diverse fauna. A high degree of small-scale variation occurs, with even adjacent samples having low similarity. Video footage from sites to the east of Bass Strait corroborates the high degree of faunal diversity over small spatial scales. Analysis of physical variables, derived from data collected on the original survey and supplemented by more recent data, show that longitude and depth are important factors in explaining the biological diversity. Despite this, overall correlation of faunal composition with physical factors is poor, indicating that other environmental variables influence the composition of benthic assemblages, and that different groups of species react to different environmental variables. It is likely that the biota reflect a series of intergrading assemblages rather than a group of discrete and repeatable species associations. Sediment facies identified can be correlated with facies from the Otway margin (Boreen et al., 1993) and those mapped previously in Bass Strait (Jones and Davies, 1983). Analysis of sediments taken from sites previously targeted by Jones and Davies (1983) indicate that sampling technique has had little impact on retention of fines. Rather, the lack of fines is a reflection of the high energy environment of much of Bass Strait. Examination of the composition of sand and gravel fractions indicates that extensive bioerosion acts in concert with physical processes to produce carbonate mud. Biogenic content in sediments shows little correlation with living communities, due in part to the abundance of soft-bodied organisms in the biota, as well as the strong imprint of post-depositional processes on sediments. The biological patterns identified in this study broadly support the divisions of the current Interim Marine and Coastal Regionalisation of Australia (IMCRA Technical Group, 1998) for Bass Strait. However, the biological assemblages are not consistent enough to be mapped. The lack of relationships between biota and sediments over the scale of the study area may reflect the scale of the study area and limitations of the statistical analyses used.