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  • 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.

  • 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 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.

  • 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.

  • The AusHydro database provides a seamless surface hydrography layer for Australia at a nominal scale of 1:250,000. It consists of lines, points and polygons representing natural and man-made features such as water courses, lakes, dams and other water bodies. The natural water course layer consists of a linear network with a consistent topology of links and nodes that provide directional flow paths through the network for hydrological analysis. This network was used to produce the National 9 second Digital Elevation Model (DEM) of Australia (http://www.ga.gov.au/nmd/products/digidat/dem_9s.jsp). Surface Hydrology Dataset is an amalgamation of two primary datasets. The first is the hydrographic component of the GEODATA TOPO 250K Series 3 product released by Geoscience Australia in 2006 . The Series 3 dataset contains the following hydrographic features: canal lines, locks, rapid lines, spillways, waterfall points, bores, canal areas, flats, lakes, pondage areas, rapid areas, reservoirs, springs, watercourse areas, waterholes, water points, marine hazard areas, marine hazard points and foreshore flats.It also provides information on naming, hierarchy and perenniality. The dataset also contains Cultural and Transport features that may intersect with hydrography features. These include: Railway Tunnels, Rail Crossings, Railway Bridges, Road Tunnels, Road Bridges, Road Crossings, Water Pipelines. Refer to the GEODATA TOPO 250K Series 3 User Guide http://www.ga.gov.au/image_cache/GA8349.pdf for additonal information The second primary dataset is based on the GEODATA TOPO-250K Series 1 water course lines completed by Geoscience Australia in 1994, which has been supplemented by additional line work captured by the Australian National University during the production of the 9 second DEM to improve the representation of surface water flow. This natural watercourse dataset consists of directional flow paths and provides a direct link to the flow paths derived from the DEM. There are approximately 700,000 more line segments in this version of the data. AusHydro 1.0 uses the natural watercourse geometry from the ANU-enhanced Series 1 data, and the attributes (names, perenniality and hierarchy) associated with Series 3 to produce a fully attributed data set with topologically correct flow paths. The attributes from Series 3 were attached using spatial queries to identify common features between the 2 datasets. Additional semi-automated and manual editing was then undertaken to ensure consistent attribution along the entire network. WatercourseLines includes a unique identifier for each line segment (AusHydro-ID) which will be used to maintain the dataset, and to incorporate higher resolution datasets in the future. The AusHydro-ID will be linked to the ANUDEM-Derived (raster) streams through a common segment identifier, and ultimately to a set of National Catchments and Reporting Units (NCRU). Purpose Surface Hydrology Dataset is the reconciliation of the hydrological features in the two data sets to produce a single authoritative national stream network and water body data set suitable for hydrological analysis at national scales. It uses the natural watercourse geometry from the ANU-enhanced Series 1 data, and the attributes (names, perenniality and hierarchy) associated with Series 3 to produce a fully attributed data set with topologically correct flow paths.

  • Drainage network containing perennial/non-perennial waterbodies and linear features such as streams, coastlines and inland shores (dataset derived from the Digital Chart of the World (DCW)). Generic information on DCW data sets The primary source for DCW is the US Defense Mapping Agency (DMA) Operational Navigation Chart (ONC) series produced by the United States, Australia, Canada, and the United Kingdom. The ONCs have a scale of 1:1,000,000, where 1 inch equals approximately 16 miles.The charts were designed to meet the needs of pilots and air crews in medium and low altitude en route navigation and to support military operational planning, intelligence briefings, and other needs. Therefore, the selection of ground features is based on the requirement for rapid visual recognition of significant details seen from a low perspective angle. The DCW database was originally published in 1992. Data currency varies from place to place depending on the currency of the ONC charts. Chart currency ranges from the mid 1960s to the early 1990s. Compilation dates for every ONC chart are included in the database. For more information on the Digital Chart of the world please browse the DCW website where you can download these data in VPF format. GA has converted these VPF format files to common GIS formats Arcview and Mapinfo. Available datasets include drainage, roads and railway networks, political areas and boundaries and population centres. Available for free download.

  • This project involved two phases, the first of which compiled reviews of recharge and discharge studies that have been undertaken in Australia. It also involved preliminary identification of the parameters (climate, soils, regolith, near-surface geology, landforms, vegetation etc.) that determine recharge and discharge rates along with a review of the appropriate scale mapping approaches available for these parameters. The second phase of the project utilised empirical relationships derived from data collected in Phase 1 of the project in a decision tree methodology that guides the user to the most appropriate estimate for recharge/discharge given the data availability. This report documents the various methods of estimating recharge and/or discharge using specifically developed Excel spreadsheets and associated input GIS data.

  • 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.

  • 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.