The Yilgarn online GIS displays a wide range of data including geological datasets, topographical data, geophysical images and seismic traverses, whole rock geochemistry and geochronology samples. It provides an aeromagnetic interpretation (lithology distribution and structure) and a geological interpretation of the Archaean Yilgarn Craton, one of Australia's key mineral provinces. The online GIS also focuses on the Leonora-Neale Transect, by providing a detailed solid geology interpretation of the section. The Yilgarn Craton occurs within Western Australia and covers 10% of the Australian continent. Exposure of bedrock is extremely poor throughout the region and most known mineral deposits occur within or adjacent to sparse outcrop. The online GIS provides a view through the poorly magnetised cover to display bedrock distribution. Interpreted rock types of the region include granite, granitic gneiss, layered intrusions and sills. Interpreted structural elements include lithological banding, faults, and dyke swarms. Also presented are several surrounding and partially overlying Proterozoic and Phanerozoic basins and provinces. The Yilgarn Craton is arguably Australia's premier mineral province, attracting more than half the mineral exploration expenditure, and producing two thirds of the gold and most of the nickel mined in the country. For this reason, the online GIS provides the ability to display all deposits in the region or the option of displaying gold or nickel deposits only. Distribution of mineral deposits can be compared to other data layers including geology, and aeromagnetic domains. This map has been produced as a GeoPDF, which is an extension to the standard PDF file format viewed using Adobe Acrobat Reader. Layers can be turned off and on to customise the view of the data, similar to using Geographic Information System tools. In addition, GeoPDF maps are georeferenced to be compatible with other coordinated geographic data. Coordinate locations and distances can be retrieved automatically. A plug-in to view GeoPDF using Adobe Acrobat Reader is available as a free download ( http://terragotech.com/solutions/map2pdf_reader.php ).

This report contains the preliminary results of Geoscience Australia marine reconnaissance survey TAN0713 to the east margin of Australia. The survey, completed as part of the Federal Government's Offshore Energy Program, was undertaken between 7 October and 22 November 2007 using the New Zealand government's research vessel Tangaroa. Leg 1 departed Wellington on 7 October and returned to Lord Howe Island on 27 October. Leg 2 departed Lord Howe Island on 28 October and returned to Wellington on 22 November.

A series of short field surveys in Jervis Bay, New South Wales, were undertaken by Geoscience Australia staff as part of the Surrogates Program in the Commonwealth Environmental Research Facilities (CERF) Marine Biodiversity Hub. The aim of the Jervis Bay field work was to collect accurately co-located physical and biological data to enable research into the utility of physical parameters as surrogates for patterns of benthic biodiversity in shallow soft-sediment habitats. In this report the survey design and sampling methods are described; selected field datasets are mapped and discussed; initial results of the laboratory analysis of seabed samples are presented; and there is a brief description of the upcoming analysis of covariance of the physical and biological datasets. The major outputs of the survey work to date are: 1. High-resolution multibeam acoustic datasets for priority areas along the open coast of Jervis Bay (Beecroft Head to Drum and Drumsticks), within the Jervis Bay National Park; and within the southern bay around Darling Road, and in the bay entrance. 2. High quality underwater video footage of benthic habitats in the Darling Road study area acquired with Geoscience Australia's shallow-water towed-video system. The video was used to characterise benthic habitat types, relief/bedform types, and biota occurrence. Characterisations were collected in real-time along bi-directional (six offshore and four alongshore) towed video transects, and were subsequently processed and mapped into three ArcGIS map layers. 3. A set of broad-scale (bay-wide) widely-spaced, co-located sediment and biotic (infauna) seabed samples from the bay's soft-sediment habitats (polychaete mounds, drift algal beds, sand flats, and sand ripple and wave habitats); 4. Sediment samples for geochemical, biogeochemical and sedimentological analyses. 5. A new acoustic doppler current profiler was successfully trialed, and is now being used to collect seabed current data in the Darling Road study area. 6. A progress report on the survey work was presented at the annual CERF Marine Biodiversity Hub's Annual Science Workshop in October 2008.

In this study, a 1 m resolution LiDAR Digital Elevation Model (DEM) has been used for predictive flood modelling and flood-risk assessment that will inform recharge studies. To produce accurate predictions of flood inundation and calculations of flood volume, the DEM was initially levelled to the Darling River floodplain by subtracting interpolated floodplain elevation trend surface from the DEM. This produces a de-trended floodplain surface. Secondly, the levelled DEM surface was adjusted to the water level reading at the Darling River gauging station (Site 425012), upstream of Weir 32, at the time when the LiDAR was acquired. Flood extents were derived by elevation slicing of the adjusted levelled DEM up to any chosen river level. River-level readings from historical and current events were extracted from the NSW Office of Water real time river data website. The flood-depth dataset is an inverted version of the flood extent grid. Predicted flood depth and extent were classified by depth/elevation slice ranges of the adjusted de-trended DEM with 25 and 50 cm increments. Predicted flood extents have been validated by comparisons to satellite images from the 1990 floods, and photographs of inundation from recent flood events. In all cases imagery and photo validation proved that predicted extents are accurate. The flood-risk predictions were then applied to a number of river level scenarios. These included (1) examination of the extent of flooding at the highest historical level; (2) determination of the river level required to completely inundate the Coonambidgal Formation scroll plain in the GWMAR1 study area (probable maximum recharge potential) and (3) an assessment of flood impacts in 0.5 m increments from 5.5 to 7 m of river level rise at the Site 425012 gauging station. In summary, this flood modelling methodology has been used to predict the extent and depth of water coverage across the Darling floodplain under different scenarios.

No abstract available

This study used angular response curves of multibeam backscatter data to predict the distributions of seven seabed cover types in an acoustically-complex area. Several feature analysis approaches on the angular response curves were examined. A Probability Neural Network model was chosen for the predictive mapping. The prediction results have demonstrated the value of angular response curves for seabed mapping with a Kappa coefficient of 0.59. Importantly, this study demonstrated the potential of various feature analysis approaches to improve the seabed mapping. For example, the approach to derive meaningful statistical parameters from the curves achieved significant feature reduction and some performance gain (e.g., Kappa = 0.62). The first derivative analysis approach achieved the best overall statistical performance (e.g., Kappa = 0.84); while the approach to remove the global slope produced the best overall prediction map (Kappa = 0.74). We thus recommend these three feature analysis approaches, along with the original angular response curves, for future similar studies.

Abstract The ability of thermal infrared (TIR) spectroscopy to characterise mineral and textural content was evaluated for soil samples collected in the semi-arid environment of north-western Queensland, Australia. Grain size analysis and separation of clay, silt and sand sized soil fractions were undertaken to establish the relationship between quartz and clay emissivity signatures and soil texture. Spectral band parameters, based on thermal infrared specular and volume scattering features, were found to discriminate fine clay mineral-rich soil from mostly coarser quartz-rich sandy soil, and to a lesser extent, from the silty quartz-rich soil. This study found that there was the potential for quantifying soil mineral and texture content using TIR spectroscopy. Key Words Soil composition, quartz, kaolinite, smectite, grain size, Tick Hill

The maps contained on this DVD are designed to provide emergency managers and others with an estimate of the probability of large tsunami generated by a large subduction zone earthquake reaching the 100m contour offshore Australia. These maps were created by generating a synthetic catalogue of possible earthquakes with associated probabilities and estimating the maximum wave height of the resulting tsunami off the coast using numerical modelling.

The Harris Greenstone Belt in the central Gawler Craton of South Australia has potential for Archaean Ni-Cu-PGE sulphide and Archaean-Proterozoic lode-Au mineralising systems. This map is a preliminary interpretation of the Precambrian basement geology based on aeromagnetics, gravity, and diamond drilling. It highlights the extensive distribution of poorly exposed Archaean komatiites and associated rocks (green) that have a strike extent of at least 300 km. The regional pattern of linear komatiitic sequences associated with ovoid granitic plutons and province-wide shear systems, is very similar to the economically important Eastern Goldfields Province in the Yilgarn Craton, Western Australia. Related products <a href="https://www.ga.gov.au/products/servlet/controller?event=GEOCAT_DETAILS&amp;catno=40975">Harris Greenstone Belt GIS Dataset</a> <a href="https://www.ga.gov.au/products/servlet/controller?event=GEOCAT_DETAILS&amp;catno=68362">Gawler Mineral Promotion: Preliminary assessment of the Ni-Cu-PGE potential of the Harris Greenstone Belt, Gawler Craton - PowerPoint</a>

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.