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  • This web service delivers metadata for onshore active and passive seismic surveys conducted across the Australian continent by Geoscience Australia and its collaborative partners. For active seismic this metadata includes survey header data, line location and positional information, and the energy source type and parameters used to acquire the seismic line data. For passive seismic this metadata includes information about station name and location, start and end dates, operators and instruments. The metadata are maintained in Geoscience Australia's onshore active seismic and passive seismic database, which is being added to as new surveys are undertaken. Links to datasets, reports and other publications for the seismic surveys are provided in the metadata.

  • The cost of landslide is underestimated in Australia because their impact and loss are not readily reported or captured. There is no reliable source of data which highlights landslide cost to communities and explains who currently pays for the hazard and how much costs are. The aim of this document is to investigate and analyse landslide costs within a Local Government Area (LGA) in order to highlight the varied landslide associated costs met by the local government, state traffic and rail authorities and the public. It is anticipated this may assist in developing a baseline awareness of the range of landslide costs that are experienced at a local level in Australia. Initial estimates in this study indicate that cumulative costs associated with some landslide sites are well beyond the budget capacity of a local government to manage. Furthermore, unplanned remediation works can significantly disrupt the budget for planned mitigation works over a number of years. Landslide costs also continue to be absorbed directly by individual property owners as well as by infrastructure authorities and local governments. This is a marked distinction from how disaster costs which arise from other natural hazard events, such as flood, bushfire, cyclone and earthquake are absorbed at a local level. It was found that many generic natural hazard cost models are inappropriate for determining landslide costs because of the differences in the types of landslide movement and damage. Further work is recommended to develop a cost data model suitable for capturing consistent landslide cost data. Better quantification of landslide cost is essential to allow for comparisons to be made with other natural hazard events at appropriate levels. This may allow for more informed policy development and decision making across all levels.

  • Faults of the Lapstone Structural Complex (LSC) underlie 100 km, and perhaps as much as 160 km, of the eastern range front of the Blue Mountains, west of Sydney. More than a dozen major faults and monoclinal flexures have been mapped along its extent. The Lapstone Monocline is the most prominent of the flexures, and accounts for more than three quarters of the deformation across the complex at its northern end. Opinion varies as to whether recent tectonism, or erosional exhumation of a pre-existing structure, better accounts for the deeply dissected Blue Mountains plateau that we see today. Geomorphic features such as the abandoned meanders at Thirlmere Lakes illustrate the antiquity of the landscape and favour an erosional exhumation model. According to this model, over-steepened reaches developed in easterly flowing streams at the Lapstone Monocline when down-cutting through shale reached more resistant sandstone on the western side of the LSC. These over-steepened reaches drove headward (westerly) knick point retreat, ultimately dissecting the plateau. However, a series of swamps and lakes occurring where small easterly flowing streams cross the westernmost faults of the LSC, coupled with over-steepened reaches 'pinned' to the fault zones in nearby larger streams, imply that tectonism plays a continuing role in the development of this landscape. We present preliminary results from an ongoing investigation of Mountain Lagoon, a small fault-bound basin bordering the Kurrajong Fault in the northern part of the LSC.

  • From 1995 to 2000 information from the federal and state governments was compiled for Comprehensive Regional Assessments (CRA), which formed the basis for Regional Forest Agreements (RFA) that identified areas for conservation to meet targets agreed by the Commonwealth Government with the United Nations. This CD was created as part of GA's contribution to the Central Highlands CRA. It contains final versions of all data coverages and shapefiles used in the project, Published Graphics files in ArcInfo (.gra), postscript (.ps) and Web ready (.gif) formats, all Geophysical Images and Landsat data and final versions of documents provided for publishing.

  • From 1995 to 2000 information from the federal and state governments was compiled for Comprehensive Regional Assessments (CRA), which formed the basis for Regional Forest Agreements (RFA) that identified areas for conservation to meet targets agreed by the Commonwealth Government with the United Nations. These 3 CDs were created as part of GA's contribution to the Eden, NSW CRA. CD1 contains original and final versions of all data coverages and shapefiles used in the project, Published Graphics files in ArcInfo (.gra), postscript (.ps) and Web ready (.gif) formats, all Geophysical Images and Landsat data and final versions of documents provided for publishing. CD2 contains the DEFUNCT directories, data that has been modified or replaced in the final version. CD3 contains the INTEGRTN directory, integration data used for evaluating options.

  • Several different techniques have recently been developed to rapidly map and characterise surface landforms and materials for groundwater recharge studies in Australia. In this example, in the Darling Floodplain of western New South Wales, regional landform mapping was carried out primarily using Google Earth imagery with hill-shaded LiDAR DEM and SPOT images as visual guide and some field validation. A second, more detailed map (compiled: 1:25,000; final usable scale: 1:30,000) included landform elements such as borrow pits, individual scrolls and oxbow lakes was compiled using LiDAR DEM. Prior to landform delineation, the LiDAR DEM required levelling to eliminate tilting in the landscape, by subtracting the floodplain trend surface from the DEM. This is particularly important in floodplains and river profiles where there can be as much as a 20 m difference between the upper and lower reaches. A best-fit trend surface, which provides an average estimation of change in slope along a single plane, was required to level the data. Once the LiDAR was levelled, an interactive contour tool in ArcGIS was used to generate graphic outlines of particular features at identified breaks in elevation using hill-shading, e.g. channel banks and dune bases. Slope and 3-D DEM visualisation also facilitated identification of these breaks. Further editing was required to assemble line work, convert it into polygons, and assign landform attributes. A greater number of landform classes were developed at this finer scale than for the regional scale. In many cases, specific landforms are characterised by particular surface materials, though sediment type can vary within a single landform class. SPOT imagery has been used to delineate surface materials. In summary, the combination of the two datasets - landforms and surface materials - has allowed for the identification of potential recharge site