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  • This disc contains PDF scans of uranium-related reports held by GA from the Australian Atomic Energy Commission archives. These reports date mostly from the 70s, with some which are much older (as early as 1901) but none newer than the early 80s. The reports are a mix of exploration reports, geological and geographical maps, proposals, feasibility studies, estimations, reserve information, drill hole data and drill cross section files. These reports pertain to the South Alligator Valley, Katherine RIver and other uranium fields within Pine Creek region. It is one of four discs containing reports concerning uranium in the Northern Territory.

  • This disc contains scanned PDF copies of uranium-related reports held by Geoscience Australia from the archives of the former Australian Atomic Energy Commission. These reports date from the early 1960s to 1980. The reports are a mix of exploration reports, geological and geographical maps, proposals, feasibility studies, estimations, reserve information, drill hole data and drill cross section files. These reports pertain to various regions around South Australia, including From Embayment, Mount Painter Province, Olary/Willyama province, Gawler Craton, Eucla Basin, Lake Eyre basin, Adelaide geosyncline and Peak & Denison Ranges. Two other discs with PDF scans of drillhole logs and gamma ray probe results in South Australia also exist and may be of interest.

  • Ongoing developments in geodetic positioning towards greater accuracies with lower latency are now allowing the measurement of the dynamics of the Earth's crust in near real time. However, in the Australian circumstance a sparsity of geodetic infrastructure has limited the application of modern, geodetic science to broader geoscience research programs. Recent enhancements to the Australian geodetic infrastructure, through the AuScope initiative, offer opportunities for research into refinement of geodetic accuracies, as well as their application to measuring crustal deformation.

  • Moreton Bay 2009 LiDAR data was captured over the Moreton Bay Regional Council area between March and June 2009. The data was acquired by AAM Hatch (now AAMGroup) and funded by Queensland and Commonwealth governments. The project area covering 2440sqkm is licenced for use by all Commonwealth, State and Local Government organisations. Data acquisition and post-processing has been controlled to achieve a vertical accuracy witihn 0.15m (RMS, 68% CI) and horizontal accuracy within 0.45 m. Horizontal coordinates are based upon Map Grid of Australia (MGA) Zone 56 projection. Vertical coordinates are referenced to Australian Height Datum (AHD). The data was captured with point density of 2.5 points per square metre and the data is available as mass point files (ASCII, LAS) and ESRI GRID files with 1m grid spacing in 1km tiles.

  • A review of the methods employed to collect 'buildings specific field data' following the impact of Tropical Cyclone Larry (March 2006) resulted in a plan to build a vehicular mounted rapid data inventory collection system to compliment post disaster surveys. The system assists to overcome issues related to restricted access, poor weather and difficult working conditions. The ability to quickly collect comprehensive information that is highly critical for both damage assessment and vulnerability model validation reduces assessment errors caused by rapid clearing of debris and repairs following the disaster, along with the use of tarpaulins which often obscure the level of damage viewed from the street. RICS consists of four 5-Megapixel Ethernet cameras attached to a tripod mounted on a vehicle, a GPS device and software written in C++. The images are compressed in jpeg format 'on-the-fly' and displayed in a Graphical User Interface (GUI) along with GPS location, bearing and speed. An additional display window shows the street-directory (UBD) roadmap and a GPS tracklog. Hot keys for instant damage assessment marking location and damage levels have been programed into the GUI. All images are geo-referenced and stored in a database.

  • The Capel and Faust basins are located in a frontier part of offshore eastern Australia, about 800 km east of Brisbane in 1300-2500 m of water. Little is known of the basin structures and geological history of this area, which is a continental fragment separated from Australia during the Cretaceous rifting of the Tasman Sea. In 2007 Geoscience Australia acquired 6000km of 2D seismic reflection and refraction data, gravity and magnetics, to begin an assessment of the petroleum prospectivity of these basins. A workflow has been developed to assist the seismic interpreter with feedback from a coherent 3D geology model that is used to predict the gravity response of the basins. This response is harmonized with the observed gravity and modified geological horizons are then returned to the seismic interpreter. An interface between Geoframe and Geomodeller has been optimized to make it very easy to do many iterations of this process, as suits the changing needs of the interpretation team.

  • Physical sedimentological processes such as the mobilisation and transport of shelf sediments during extreme storm events give rise to disturbances that characterise many shelf ecosystems. The intermediate disturbance hypothesis predicts that biodiversity is controlled by the frequency of disturbance events, their spatial extent and the amount of time required for ecological succession. A review of available literature suggests that periods of ecological succession in shelf environments range from 1 to over 10 years. Physical sedimentological processes operating on continental shelves having this same return frequency include synoptic storms, eddies shed from intruding ocean currents and extreme storm events (cyclones, typhoons and hurricanes). Modelling studies that characterise the Australian continental shelf in terms of bed stress due to tides, waves and ocean currents were used here to create a map of ecological disturbance, defined as occurring when the Shield's parameter exceeds a threshold of 0.25. We also define a dimensionless ecological disturbance ratio (ED) as the rate of ecological succession divided by the recurrence interval of disturbance events. The results illustrate that on the outer part of Australia's southern, wave-dominated shelf the mean number of days between threshold events that the Shield's parameter exceeds 0.25 is several hundred days.

  • Crust predating 3.0 Ga within the Australian continent has previously been identified only in relatively restricted areas of the Yilgarn and Pilbara Cratons of Western Australia. Here we report the discovery of early Mesoarchean (~3150 Ma) rocks in the eastern Gawler Craton of South Australia. Rocks of broadly Mesoarchean age have been inferred by some authors to exist at depth beneath the Gawler Craton (Creaser and Fanning, 1993; Daly and Fanning, 1993), but no rocks of this age have been identified previously at the surface. The newly identified Mesoarchean granites and gneisses crop out across at least ~20 x 30 km and, on the basis of inherited zircon and Nd-isotopic compositions, are inferred to be present at depth beneath a region of at least ~1500 km2.

  • Predictive maps of the subsurface can be generated when geophysical datasets are modelled in 2D and 3D using available geological knowledge. Inversion is a process that identifies candidate models which explain an observed dataset. Gravity, magnetic, and electromagnetic datasets can now be inverted routinely to derive plausible density, magnetic susceptibility, or conductivity models of the subsurface. The biggest challenge for such modelling is that any geophysical dataset may result from an infinite number of mathematically-plausible models, however, only a very small number of those models are also geologically plausible. It is critical to include all available geological knowledge in the inversion process to ensure only geologically plausible physical property models are recovered. Once a set of reasonable physical property models are obtained, knowledge of the physical properties of the expected rocks and minerals can be used to classify the recovered physical models into predictive lithological and mineralogical models. These predicted 2D and 3D maps can be generated at any scale, for Government-funded precompetitive mapping or drilling targets delineation for explorers.