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  • The Surface Hydrology Points (Regional) dataset provides a set of related features classes to be used as the basis of the production of consistent hydrological information. This dataset contains a geometric representation of major hydrographic point elements - both natural and artificial. This dataset is the best available data supplied by Jurisdictions and aggregated by Geoscience Australia it is intended for defining hydrological features.

  • Geoscience Australia (GA) was invited by Murray-Darling Basin Authority (MDBA) in 2010 to participate in an evaluation of the Intermap IFSAR (Interferometric Synthetic Aperture RADAR) data that was acquired as part of the Murray-Darling Basin Information Infrastructure Project Stage 1 (MDBIIP1) in 2009. This evaluation will feed into the business case for Stage 2 of the project. As part of the evaluation GA undertook the following: 1. A comparison of the IFSAR Digital Surface Model (DSM) and Digital Terrain Model (DTM) with a recent LiDAR acquisition, covering approximately 9000Km2 of the Lower Darling Region. It focused on assessment of the data over various land cover and terrain types and identified opportunities and issues with integrating IFSAR with LiDAR. 2. A comparison of the IFSAR Vegetation Canopy Surface (DSM minus DTM) with the Lower Darling LiDAR Canopy Elevation Model (CEM). 3. A comparison between currently mapped man-made and natural water bodies over the Murray-Darling Basin with the IFSAR derived products (water mask). 4. Application of the National Catchment Boundaries (NCBs) methodology to the IFSAR data and comparison with the delineated watersheds from PBS&J (Intermap's sub-contractor). This report outlines the findings of this evaluation based on the 4 items above MDBA requested.

  • A collaborative field trial of the Quester-Tangent View Series 5 single beam acoustic benthic mapping system was recently conducted in Wallis Lake by Geoscience Australia and Quester Tangent Corporation. The survey involved acquisition of the acoustic backscatter data from the northern channels and basins of Wallis Lake. Quester-Tangent software (IMPACT v3) was used to classify acoustic echograms that returned from the lake bottom into statistically different acoustic classes, using principal components analysis. Six acoustically different substrate types were identified in the Wallis Lake survey area. Ground-truthing was undertaken to identify the sedimentological and biological features of the lake floor that influenced the shape of the return echograms. For each sample, measurements were made of grain size, wet bulk density, total organic carbon, CaCO3 content, and mass of coarse fraction (mainly shell) material. Statistical cluster analysis and multi-dimensional scaling were utilised to identify any physical similarities between groups of ground-truthing sites. The analysis revealed four distinct and mappable substrate types in the study area. The degree of association between acoustic classes and measured sediment parameters was also quantified. Cluster and MDS analysis revealed that, based on the parameters measured, the six acoustic classes were not uniquely linked to the sediment groups, suggesting that factors other than the sediment parameters alone are influencing the acoustic signal. The spatial interpretation of the Wallis Lake Quester-Tangent data represents the first quantification of non-seagrass habitats in the deeper areas of the lake, and provides a useful indicatior of benthic habitat diversity and abundance. For future studies, a more quantitative measure of faunal burrow size and density, and also other sedimentary bedforms, is recommended.

  • An area of about 12,000 square miles was mapped in the field seasons 1950-51. It contains four Pre-Cambrian rock groups ranging from Archaeozoic to Uppermost Proterozoic. The main groups in the area, the Mt. Isa and Lawn Hill Groups, are shallow-water geosynclinal sediments involved in a Proterozoic orogeny which resulted in fairly intensive folding along dominantly north-south axes, together with much faulting. The geological features discussed in this report include physiography, topography, stratigraphy, igneous activity, structure, mineral deposits and water supply.

  • On May 3rd, and again on June 1st, the author visited the Cotter dam to investigate a reported loss of water from the fault on the northern side of the wall. This report gives an account of these visits, together with the author's observations and conclusions in relation to the reported water loss.

  • This report presents the results of a study by Geoscience Australia of Stokes Inlet and Wellstead Estuary, located in southwestern Western Australia, based on data collected during surveys in March 2006 and May 2007. It includes the present day rates of organic matter breakdown in the sediments of these estuaries, sediment and porewater properties, sedimentation rates, and an account of the historical environmental changes to these estuaries based on the sediment record. In the report you will find: 1. Purpose and background 2. Environmental Setting 3. Methods 4. Benthic Chambers 5. Sediment Cores and Grabs 6. Results and Discussions 7. Environmental conditions during the survey 8. Present-day nutrient dynamics in Stokes Inlet 9. Palaeoenvironmental reconstruction 10. Key conclusions

  • This study explores how differences in ionic composition of south-eastern Australian saline lake waters, caused by path differentiation according to the Eugster-Jones-Hardie models of solute evolution and halite recycling, influence species composition of ostracod faunas. Ostracod occurrences are reported as physiologically important ionic ratios set in a marine-meteoric framework, with chemical boundaries determined by mixing and evaporation models. The occurrence of halophilous ostracods coincides with changes in the ionic structure of lake waters. Chemical diversity is found to be biologically important, with most ostracods preferring a specific pathway of the Eugster-Jones-Hardie models. Path preference predominantly reflects the different tolerance ranges of species to a combination of Na<sup>+</sup>/H<sup>+</sup>, Na<sup>+</sup>/Ca<sup>2+</sup> and alkalinity/Cl<sup>-</sup> activity ratios, which probably govern acid-base balance and Na<sup>+</sup> and CA<sup>2+</sup> regulation. An Alkalinity/Cl<sup>-</sup> activity ratio of ~-2.3 corresponds to the main division in the ostracod data and reflects the abrupt change in alkalinity/Cl<sup>-</sup> ratios that occurs when a seawater-like solute matrix is diluted with a large amount of meteoric water (95%). Most halobiont ostracods occur in waters enriched with Na-Cl as a result of halite recycling. Evidence is presented that the same geochemical processes are relevant to other aquatic organisms (e.g. zooplankton, diatoms, insects) found in salt water.

  • This point dataset contains the major desalination plants in Australia.

  • The National Major Dam Walls dataset presents the spatial locations; in point and polygon format, of all known major dam walls within Australia.