In 2008-2009 Geoscience Australia, contracted Fugro Airborne Surveys and Geotech Airborne, to respectively acquire TEMPEST and VTEM airborne electromagnetic (AEM) data with broad line spacings covering more than 71 000 km² in the Pine Creek region, Northern Territory. The Pine Creek survey (Figure 1) is the second regional AEM survey funded by the Onshore Energy Security Program (OESP) at Geoscience Australia. Geoscience Australia funded the flying of 19 500 line km, subscriber companies funded 10 400 line km. The 5 000 m line spacing provide regional information with 1 666 m, 555 m and closer line spacing providing detail for mineral systems analysis and deposit scale mapping. One of the main survey objectives was to reduce exploration risk and encourage exploration in the region by mapping, under cover, in areas where gravity and magnetics are quiet. Geological targets included detecting: conductive unites within the Pine Creek Orogen (PCO) sequence; Kombolgie Sandstone / PCO unconformity; Tolmer Group/ Finniss River Group unconformity. Geoscience Australia undertook conductivity logging (Figure 2) in the Pine Creek region. Conductivity logs were processed and as input into forward models, ground truth AEM results and for geological interpretations. To facilitate interpretation, subsurface electrical conductivity predictions using a layered earth inversion (sample by sample) algorithm developed by Geoscience Australia (GA-LEI) were derived from the AEM survey data. Conductivity characterisation of large regional units using the AEM data show: the Rum Jungle Complex is a consistently resistive area with an average conductivity value of less than 2 m/S; the Mt Partridge Group has a conductivity value up to 100 m/S; the Kombolgie Sandstone has a conductivity range of less than 2 m/S in more areas. Detecting conductivity contrasts in areas with known uranium prospectivity aids in a mineral systems analysis and geological interpretation of uranium deposits.

Geoscience Australia has developed an interactive 3D viewer for three national datasets; the new Radiometric Map of Australia, the Magnetic Anomaly Map of Australia, and the Gravity Anomaly Map of the Australian Region. The interactive virtual globe is based on NASA's open source World Wind Java Software Development Kit (SDK) and provides users with easy and rich access to these three national datasets. Users can view eight different representations of the radiometric map and compare these with the magnetic and gravity anomaly maps and satellite imagery; all draped over a digital elevation model. The full dataset for the three map sets is approximately 55GB (in ER Mapper format), while the compressed full resolution images used in the virtual globe total only 1.6GB and only the data for the geographic region being viewed is downloaded to users computers. This paper addresses the processes for selecting the World Wind application over other solutions, how the data was prepared for online delivery, the development of the 3D Viewer using the Java SDK, issues involving connecting to online data sources, and discusses further development being undertaken by Geoscience Australia.

The Perth 2008 LiDAR data was captured over the Perth region during February, 2008. The data was acquired by AAMHatch (now AAMGroup) and Fugro Spatial Solutions through a number of separate missions as part of the larger Swan Coast LiDAR Survey that covers the regions of Perth, Peel, Harvey, Bunbury and Busselton. The project was funded by Department of Water, WA for the purposes of coastal inundation modelling and a range of local and regional planning. The data are made available under licence for use by Commonwealth, State and Local Government. The data was captured with point density of 1 point per square metre and overall vertical accuracy has been confirmed at <15cm (68% confidence). The data are available as a number of products including mass point files (ASCII, LAS) and ESRI GRID files with 1m grid spacing. A 2m posting hydrologically enforced digital elevation model (HDEM) and inundation contours has also been derived for low lying coastal areas.

Obtaining reliable predictions of the subsurface will provide a critical advantage for explorers seeking mineral deposits at depth and beneath cover. A common approach in achieving this goal is to use deterministic property-based inversion of potential field data to predict a 3D subsurface distribution of physical properties that explain measured gravity or magnetic data. The non-uniqueness of inversions of potential field data mandates careful and consistent parameterization of the problem to ensure realistic solutions. Including all prior geological knowledge as constraints on the inversion also helps ensure that the recovered predictions are consistent with both the geophysical data and the geological knowledge. We review how potential field inversions are best applied for mineral exploration problems using the UBC-GIF inversion algorithms. We use examples to emphasise the importance of mesh design and applying appropriate data processing, and identify the approach for defining key parameters such as data uncertainty, potential field weighting functions, and numerical parameters that approximate prior geological knowledge of in situ trends, geometries and properties. Consistent application of these techniques will ensure the most reliable predictive physical property models for explorers.

Advances in computer technology have provided the opportunity to present geoscience information in new and innovative ways. The use of web-based three-dimensional interactive models, animations and fly-throughs significantly enhances our ability to communicate complex geometries and concepts not only to the geoscientific community but also, just as importantly, to the general public. Projects within Geoscience Australia currently use a range of GIS, remote sensing, and modelling packages for visualisation of fundamental and derived data. In the main each of these packages also has the ability to produce, as an output, some form of model or animation sequence displaying the results of the visualisation. In most cases however, these outputs are generally not of sufficient quality or do not provide adequate functionality without further processing or editing. Geoscience Australia has adopted a multi-disciplinary approach to 3D visualisation encompassing cartography, GIS, remote sensing, graphic design, programming, web, and video editing to the post-processing of these visualisations. This paper examines the benefits of using models and movies for the visualisation of geoscience and briefly discusses the current workflows and presentation techniques used by the Geo-Visualisation team within Geoscience Australia.

Geoscience Australia collects and manages large amounts of data for Australia's marine zone, including bathymetry data and the legal boundaries of petroleum acreage release areas. Communicating this information to non-specialists can be difficult. To overcome this communication problem Geoscience Australia uses innovative visualisation techniques, including 3D flythroughs and video editing, to integrate raster and vector geospatial data into enhanced multimedia products. Geoscience Australia has used these techniques for a number of years and the resulting products are highly regarded by stakeholders interested in marine zone management and petroleum exploration. This paper examines four case studies where these innovative techniques were used to effectively communicate marine zone information with a wide audience.

The Georgina-Arunta 3D project is a body of work that is predominantly focussed around delivery of 3D geophysical and geological data and interpretations to support the seismic data in the region. By integrating all available data in the region with a wide variety of potential-field techniques, a robust 3D map is able to be produced.

Australia's marine jurisdiction is one of the largest and most diverse in the world and surprisingly our knowledge of the biological diversity, marine ecosystems and the physical environment is limited. Acquiring and assembling high resolution seabed bathymetric data is a mandatory step in achieving the goal of increasing our knowledge of the marine environment because models of seabed morphology derived from these data provide useful insights into the physical processes acting on the seabed and the location of different types of habitats. Another important application of detailed bathymetric data is the modelling of hazards such tsunami and storms as they interact with the shelf and coast. Hydrodynamic equations used in tsunami modelling are insensitive to small changes in the earthquake source model, however, small changes in the bathymetry of the shelf and nearshore can have a dramatic effect on model outputs. Therefore, accurate detailed bathymetry data are essential. Geoscience Australia has created high resolution bathymetry grids (at 250, 100, 50 and 10 metres) for Christmas, Cocos (Keeling), Lord Howe and Norfolk Islands. An exhaustive search was conducted finding all available bathymetry such as multibeam swath, laser airborne depth sounder, conventional echo sounder, satellite derived bathymetry and naval charts. Much of this data has been sourced from Geoscience Australia's holdings as well as the CSIRO, the Australian Hydrographic Service and foreign institutions.Onshore data was sourced from Geoscience Australia and other Commonwealth institutions. The final product is a seamless combined Digital Bathymetric Model (DBM) and Digital Elevation Model (DEM).The new Geoscience Australia grids are a vast improvement on the existing publicly available grids.

The management of water and groundwater resources is increasingly dependent on the integration of large complex datasets to visualise and model hydrological systems. The development of conceptual geological and hydrological models in the Broken Hill Managed Aquifer Recharge (BHMAR) project has involved the integration of high resolution LiDAR, remote sensing (Landsat, SPOT), airborne electromagnetic (AEM), ground and in-river electrical surveys, and point datasets from surface sites and drillholes (borehole NMR, induction and gamma logs as well as hydrogeochemical and lithological data). Products derived from the integration of these datasets include 3D maps of hydrostratigraphy, groundwater quality, hydraulic conductivity, recharge maps, 2D displays of data (e.g. potentiometric surface maps), 3D volume shapes of groundwater resources and managed aquifer storage targets, and lithological, hydrogeochemical and hydrological data in drillholes. These datasets will be used to parameterise groundwater models at regional and borefield scales. To facilitate effective communication of such large and complex geoscience datasets and project results to a wide range of stakeholders, Geoscience Australia (GA) has recently developed an interactive 3D virtual globe viewer. The interactive virtual globe is built on NASA's open source World Wind Java Software Development Kit (SDK) and provides users with easy and rich access to geoscientific data.The BHMAR project required further development of the existing viewer platform in order to display complex 3D hydrogeological, hydrogeophysical and hydrogeochemical data (points, lines, 2D surface and 3D shapes). The final product includes support for a variety of geo-referenced raster data formats, as well as vector data such as ESRI shapefiles and native support for a variety of GOCAD data types including TSurf, SGrid, Voxet and PLine.

Tomographic images of Southeast Asia and Australia were created by inverting the travel-times of the Rayleigh wave Green's functions retrieved from cross-correlations of the ambient seismic noise. The travel-times of the Green's functions are inverted with a nonlinear two dimensional inversion scheme to map the seismic velocity perturbations of the Earth. Continuous records from the vertical components of 187 permanent broad-band seismic stations operated from 2007 to 2008 are processed. We limit our picks only for Green's functions with interstation separation between 1o and 60o. This ensures that only wide scale anomalies are included in the tomographic inversions. By employing a nonlinear wavefront tracker for the forward problem, we avoid the artefacts of the deviations from the great circle path assumptions for very long interstation paths. We conduct dispersion measurements of group velocities between 6 and 50 seconds by narrowly filtering the envelopes of the extracted Green's functions. The Rayleigh waves for the selected periods sample the Earth from upper-crust (~9 km) to uppermost mantle (~90 km). The tomographic images reveal heterogeneous structure of Australia marking major sediment deposits on shallow layers and the high-velocity structure of the Western Australia cratons composed of ancient Archaean and Proterozoic blocks. Low velocity zones in deeper layers correlate well with the areas of high heat flow and agree with the results of recent surface wave tomographic studies. The Sunda Arc is characterized by prominent low-velocity zones located below the western tip of Java, Java Sea, and Banda Sea for longer periods.