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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.

  • This service provides Australian surface hydrology, including natural and man-made features such as water courses (including directional flow paths), lakes, dams and other water bodies. The information was derived from the Surface Hydrology database, with a nominal scale of 1:250,000. The service contains layer scale dependencies.

  • 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.

  • This service has been created specifically for display in the National Map and the symbology displayed may not suit other mapping applications. The service includes natural and man-made surface hydrology 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.

  • 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 point 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.

  • This specification describes the aggregation of jurisdictional data that is maintained by Geoscience Australia. Currently this data is made up of a mixture of scale ranging from 1:25,000 to 1:250,000 across the continent.

  • 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 linear 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.

  • The Australian Topographic map service is seamless national dataset coverage for the whole of Australia. The map portrays detailed graphic representation of features that appear on the Earth's surface. These features include cultural, hydrography and relief themes. SS, MS and LS refer to Small, Medium and Large Scale datasets.