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  • This dataset provides the spatially continuous data of seabed gravel (sediment fraction >2000 µm), mud (sediment fraction < 63 µm) and sand content (sediment fraction 63-2000 µm) expressed as a weight percentage ranging from 0 to 100%, presented in 0.0025 decimal degree (dd) resolution raster grids format and ascii text file. The dataset covers the Vlaming sub-basin in the Australian continental EEZ. This dataset supersedes previous predictions of sediment gravel, mud and sand content for the basin with demonstrated improvements in accuracy. Accuracy of predictions varies based on density of underlying data and level of seabed complexity. Artefacts occur in this dataset as a result of insufficient samples in relevant regions. This dataset is intended for use at the basin scale. The dataset may not be appropriate for use at smaller scales in areas where sample density is insufficient to detect local variation in sediment properties. To obtain the most accurate interpretation of sediment distribution in these areas, it is recommended that additional samples be collected and interpolations updated.

  • Collection of Geoscience Australia's high-resolution elevation surveys collected using Light Detection and Ranging (LiDAR) and other instrument systems. <b>Value: </b>Describes Australia's landforms and seabed is crucial for addressing issues relating to the impacts of climate change, disaster management, water security, environmental management, urban planning and infrastructure design. <b>Scope: </b>Selected areas of interest around Australia.

  • Multibeam sonar swath-mapping has revealed small submarine volcanic cones on the northeastern Lord Howe Rise (LHR), a submerged ribbon continent. Two such cones, aligned NNW and 120 km apart, were dredged at 23-24Degrees S. Water depth is about 1150 m nearby: the southern cone rises to 750 m and the northern to 900 m. Volcanic rocks dredged from the cones are predominantly highly altered hyaloclastites with minor basalt. The clasts are mostly intensely altered vesicular brownish glass with lesser basalt, in zeolitic, clayey, micritic or ferruginous cement. Lavas and hyaloclastites contain altered phenocrysts of olivine and plagioclase, and fresh clinopyroxene. The latter have compositions between acmite and Ti-augite, and match well clinopyroxene phenocrysts in undersaturated intraplate basanitic mafic lavas. Interbedded micrites in the volcaniclastics represent calcareous ooze that was deposited with (or later than) the volcanic pile. Foraminifera indicate that the oldest micrite is late Early Miocene (~16 Ma), and that the original ooze was deposited in cool water. Late Miocene to Pliocene micrites, presumed to be later infillings, all contain warm water forms. This evidence strongly suggests that both cones formed in pelagic depths in the Early Miocene. Ferromanganese crusts from the two cones are up to 7 cm thick and similar physically, but different chemically. The average growth rate is 3 mm/m.y.. Copper, nickel and cobalt content are relatively high in the north, but copper does not exceed 0.08 wt %, nickel 0.65% and cobalt 0.25%. The Mn:Fe ratio is high in the south (average 13.7) suggesting strong hydrothermal influence. Such small volcanic cones related to intraplate hotspot-type magmatism may occur in extensive fields like those off southern Tasmania. On Lord Howe Rise, the known small volcanic cones coincide with broad gravity highs in areas of shallow continental basement. The highs probably represent Neogene plume-related magmatism. The thick continental crust may dissipate and spread the magma widely, whereas plumes may penetrate thin oceanic crust more readily and build larger edifices. The correspondence of the ages derived from micropalaeontology and from extrapolating from nearby dated hotspot traces support such a genesis. Accordingly, gravity highs in the right setting may help predict fields of small volcanic seamounts.

  • This includes collection of core from sonic drilling and soil and water samples from boreholes and surface water. The Core is stored in plastic in core trays (4 x 1m). The water samples are disposed of once analysed.

  • A nationally-consistent wave resource assessment is presented for Australian shelf (<300 m) waters. Wave energy and power were derived from significant wave height and period, and wave direction hindcast using the AusWAM model for the period 1 March 1997 to 29 February 2008 inclusive. The spatial distribution of wave energy and power is available on a 0.1° grid covering 110'156° longitude and 7'46° latitude. Total instantaneous wave energy on the entire Australian shelf is on average 3.47 PJ. Wave power is greatest on the 3,000 km-long southern Australian shelf (Tasmania/Victoria, southern Western Australia and South Australia), where it widely attains a time-average value of 25-35 kW m-1 (90th percentile of 60-78 kW m-1), delivering 800-1100 GJ m-1 of energy in an average year. New South Wales and southern Queensland shelves, with moderate levels of wave power (time-average: 10-20 kW m-1; 90th percentile: 20-30 kW m-1), are also potential sites for electricity generation due to them having a similar reliability in resource delivery to the southern margin. Time-average wave power for most of the northern Australian shelf is <10 kW m-1. Seasonal variations in wave power are consistent with regional weather patterns, which are characterised by winter SE trade winds/summer monsoon in the north and winter temperate storms/summer sea breezes in the south. The nationally-consistent wave resource assessment for Australian shelf waters can be used to inform policy development and site-selection decisions by industry.

  • A growing need to manage marine biodiversity at local, regional and global scales cannot be met by applying the limited existing biological data sets. Abiotic surrogacy is increasingly valuable in filling the gaps in our knowledge of biodiversity hotspots, habitats needed by endangered or commercially valuable species and systems or processes important to the sustained provision of ecosystem services. This review examines the utility of abiotic surrogates across spatial scales with particular regard to how abiotic variables are tied to processes which affect biodiversity and how easily those variables can be measured at scales relevant to resource management decisions.

  • Pitcher, C.R., P.J., Doherty, and T.J. Anderson. (2008). Seabed environments, habitats and biological assemblages. pages 51-58. In: Hutchings, P.A., M.J. Kingsford, and O. Hoegh-Guldberg (eds.). The Great Barrier Reef: Biological, Environment and Management. CSIRO Publishing, Springer.

  • Hydrogeological map data for research and analysis applications, most commonly in GIS systems. Georeferenced, attributed, GIS vector format data of hydrogeological map information at all scales.

  • The collection consists of field, processed and navigation seismic data plus acquisition processing and interpretation reports. The collection is derived from the marine seismic field programs undertaken by Geoscience Australia, Australian Geological Survey Organisation (AGSO) and Bureau of Mineral Resources (BMR) since the 1980s. Data used by petroleum industry for exploration, GA for frontier petroleum programs and academia for research. 80% of data requests from industry.

  • A number of physical properties (water content, porosity, wet and dry bulk densities, andgrain size) and the bulk chemical composition (percent calcium carbonate) of several corescollected from the Australian continental shelf and slope have been determined. Thecontinental shelf sediments were collected from water depths <200m in the Torquay Sub-basin and Vulcan Graben. Continental slope sediments were collected from water depthsof between 500 m and >4000 m offshore Evans Head (NSW), the Exmouth Plateau, thePerth Basin and the Ceduna Terrace in The Great Australian Bight. Trends between physical properties and the bulk chemical composition have beencompared and contrasted for continental shelf and slope sediments. Increasing carbonatecontent for sediments from the continental slope are associated with increasing wet bulkdensities. A second order polynomial fit to the data was similar to that found for deep-sea,southeast Pacific cores examined by Lyle and Dymond (1969). In contrast, the continentalshelf sediments show that with increasing carbonate content there is a decrease in wet bulkdensity, although the data are very scattered and the trend is poorly defined. Data from continental shelf sediments show that with increasing proportions of 'fine-grained' (<631.1m) sediment fraction, there is an increase in porosity. Continental slopesediments show no clear relationship between the porosity of the sediments and thepercentage of 'fine-grained' (< 6311m) sediment fraction. For continental shelf sediments, increasing carbonate content is associated with a decreasein the 'fine-grained' (<63 rim) sediment fraction. The continental slope sediments show norelationship between carbonate content and the percent < 63 gm sediment fraction.