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  • The combined analysis of airborne electromagnetics (AEM), airborne gamma-ray spectrometry (AGRS), magnetics and a digital elevation model with ground-based calibration, has enable construction of a 3D architectural and landscape evolution model of valley fill deposits around the township of Jamestown in South Australia. The valley fill sediments consist of traction, suspension and debris-flow deposits that range in age (optically stimulated luminescence OSL dating) from 102 ka (±12) to the present day. A sediment isopach map generated from the AEM dataset reveals the 3D structure of the valley-fill deposits. The sediments are up to 40 m thick within asymmetrical valleys and are the result of colluvial fan, floodplain and sheet-wash processes. The sediments fine upwards with a higher proportion of coarser bed load deposits toward the base and fine sand, silt and clay towards the top of the sequence. A strong linear correlation between airborne K response and soil texture allowed the percentage of surface silt to be modelled over the depositional landforms. The sediments are thought to have been derived by a combination of aeolian dust accessions, and weathering and erosion of bedrock materials within the catchment. Older drainage lines reflected in the distribution of relatively closely spaced and well connected 'magnetic channels' differ markedly from present day streams that are largely ephemeral and interrupted. This is thought to reflect a change in local hydrology and associated geomorphic processes from relatively high to lower energy conditions as the valley alluviated. These hydrological changes are likely to be associated with a drying climate, lower recharge and runoff.

  • Contains a medium scale vector representation of the topography of Australia. The data include the following themes: Hydrography - drainage networks including watercourses, lakes, wetlands, bores and offshore features; Infrastructure - constructed features to support road, rail and air transportation as well as built-up areas, localities and homesteads. Utilities, pipelines, fences and powerlines are also included; Relief - features depicting the terrain of the earth including 50 metre contours, spot heights, sand dunes, craters and cliffs; Vegetation - depicting forested areas, orchards, mangroves, pine plantations and rainforests; and Reserved Areas - areas reserved for special purposes including nature conservation reserves, aboriginal reserves, prohibited areas and water supply reserves.

  • Contains a medium scale vector representation of the topography of Australia. The data include the following themes: Hydrography - drainage networks including watercourses, lakes, wetlands, bores and offshore features; Infrastructure - constructed features to support road, rail and air transportation as well as built-up areas, localities and homesteads. Utilities, pipelines, fences and powerlines are also included; Relief - features depicting the terrain of the earth including 50 metre contours, spot heights, sand dunes, craters and cliffs; Vegetation - depicting forested areas, orchards, mangroves, pine plantations and rainforests; and Reserved Areas - areas reserved for special purposes including nature conservation reserves, aboriginal reserves, prohibited areas and water supply reserves.

  • The Lapstone Structural Complex (LSC) comprises a series of north-trending faults and monoclinal flexures forming the eastern margin of the Blue Mountains Plateau, ~50 km west of the Sydney CBD. The LSC is considered a potential source of large earthquakes, however its evolution, and in particular its tectonic history is not well constrained. The LSC is bounded to the west by the Kurrajong Fault System (KFS), a series of <i>en echelon </i>reverse faults downthrown to the west. Streams crossing the LSC oversteepen by about 2-5 times over these faults. This study aims, through longitudinal profile analysis of 18 streams crossing the LSC coupled with field observation, to determine whether the oversteepening can be attributed to a lithological change at the faults, or tectonically-induced disequilibrium. Two approaches are used. Firstly, plots of log slope versus log distance (DS plots) are produced for each of the streams. As a result of noise in the topographic data, these results are inconclusive in demonstrating either situation. Secondly, an area-slope relationship, defined by <i>A<sup>0.4</sup>S</i> (where A = area and S = slope), is plotted against downstream distance. This factor is derived from the stream incision law, <i>dz/dt </i>= <i>KA<sup>m</sup>S<sup>n</sup></i>, where <i>K</i> is assumed to be constant, and <i>m</i> and<i> n</i> are positive constants relating to erosional processes, and basin hydrologic and geometric factors. The analysis shows that in all but two streams, values for <i>A<sup>0.4</sup>S</i> are at a maximum over the LSC. Peak <i>A<sup>0.4</sup>S</i> values of about 0.2 are estimated to be equivalent to vertical incision rates of about 70 m/Ma. <i>A<sup>0.4</sup>S</i> varies with lithology; however the lithological effect is demonstrated to be of similar magnitude or smaller than the apparent structural control exerted by the LSC. All streams with catchment areas less than 100 km<sup>2</sup> have developed swamps upstream of faults on the LSC. Sediment accumulated in these swamps is generally 0.5-4 m thick, but reaches 14 m in Burralow Swamp. In Blue Gum Creek and Burralow Swamps, the sedimentary sequence includes an organic clay layer indicative of low-energy depositional conditions. Previous radiocarbon dating and pollen analysis suggests the sediment is of Pleistocene age. The elevation of the clay layer is similar to that of bedrock downstream of the faults, consistent with damming related to from tectonically induced uplift.

  • Four data formats are available for download, three vector (e00, mif, shp) and one raster (ecw).

  • A structural transect along a ridge entering Wheeny Gap from the west provides important insight into the nature of faults comprising the Lapstone Structural Complex (LSC). Sheared sandstone outcropping along the ridge east of the Kurrajong fault scarp suggests that the Kurrajong Fault is a steeply east-dipping reverse-fault, in accordance with the interpretation of seismic profiles further to the south. A previously unrecognised west-dipping reverse fault (Wheeny Gap Fault) with at least several tens of metres of displacement was observed in a cliff face on the northern side of Wheeny Gap, several hundred metres east of the Kurrajong Fault. Relatively recent activity is suggested on the Wheeny Gap Fault as it laterally displaces the cliff face formed during the passage of a knickpoint relating to initial relief generation across the Lapstone Monocline up Wheeny Creek. Earthquake hypocentres recorded over the last several decades occur predominantly at depth to the west, and have been used to suggest the presence of a blind west-dipping reverse fault, into which the Kurrajong and Wheeny Gap faults must link at depth. We present an evolutionary model for the LSC based upon this architecture which reconciles evidence for late Cenozoic uplift across the LSC and the observation that the Rickabys Creek Gravels overlie shale on the Cumberland Plain and sandstone on the Lapstone Monocline. This model suggests that the findings of a major seismic hazard assessment of the Sydney Basin, which concludes that magnitude MW7.0 and greater earthquake events might be expected on the LSC on average every 15-30 ka, should be treated with caution. This expectation of regular recurrence must be tempered by the possibility that a large part of the relief relating to the complex might have formed in the late Miocene or earlier, and the evidence from other Australian intraplate faults suggesting that large earthquake occurrence is markedly temporally clustered.

  • Contains a medium scale vector representation of the topography of Australia. The data include the following themes: Hydrography - drainage networks including watercourses, lakes, wetlands, bores and offshore features; Infrastructure - constructed features to support road, rail and air transportation as well as built-up areas, localities and homesteads. Utilities, pipelines, fences and powerlines are also included; Relief - features depicting the terrain of the earth including 50 metre contours, spot heights, sand dunes, craters and cliffs; Vegetation - depicting forested areas, orchards, mangroves, pine plantations and rainforests; and Reserved Areas - areas reserved for special purposes including nature conservation reserves, aboriginal reserves, prohibited areas and water supply reserves.

  • These pages comprise the National Geoscience Datasets Internet Facility which delivers AGSO clients online access to AGSO's National scale spatial geoscience information. AGSO has responsibility for the production and online access to primary geoscience information of relevance to resource issues for industry, government and the general public, provided in the form of digital datasets that cover the Australian continent and/or Australian marine jurisdictional areas. This facility will provide efficient, modern digital-era access to all the geoscience information available in current maps and associated digital databases at the best possible resolution. To add to this as new geoscience datasets are released they will become available on the National Geoscience Datasets download page and be viewable within the National datasets online GIS web mapping tool.

  • The Surface Hydrology Lines (National) dataset presents the spatial locations of surface hydrology line features and its attributes. The dataset represents the Australia's surface hydrology at a national scale. It includes natural and man-made geographic features such as: watercourses, canals, pipelines, etc. This product presents line hydrology features with full topological connectivity and flow paths for the entire continental of Australia.

  • This service has been created specifically for display in the National Map and the symbology displayed may not suit other mapping applications. Information included within the service includes the polygon/area locations for surface hydrology, including natural and man-made features such as water courses (including directional flow paths), lakes, dams and other water bodies and marine themes. The data is sourced from Geoscience Australia 250K Topographic data and Surface Hydrology data. The service contains layer scale dependencies.