From 1 - 10 / 69
  • The dataset provides the spatially continuous data of the seabed gravel content (sediment fraction >2000 µm) expressed as a weight percentage ranging from 0 to 100%, presented in 0.01 decimal degree resolution raster format. The dataset covers the Australian continental EEZ, including seabed surrounding Tasmania. It does not include areas surrounding Macquarie Island, and the Australian Territories of Norfolk Island, Christmas Island, and Cocos (Keeling) Islands or Australia's marine jurisdiction off of the Territory of Heard and McDonald Islands and the Australian Antarctic Territory. This dataset supersedes previous predictions of sediment gravel content for the Australian Margin 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 national and regional scales. The dataset may not be appropriate for use at local 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.

  • Several gravity cores from the west (3), south (3) and east (5) Australian continental margin have been sampled and analysed for magnetic susceptibility, percent calcium carbonate, Fe203, Al203 and Si02 (% wt) and other trace element contents. Thecores sampled from the west Australian continental margin were from the Exmouth Plateau, and the Carnarvon Terrace. Sampling from the south Australian continental margin was from the west Ceduna Terrace and the Eyre Terrace and the cores sampled from the east Australian continental margin were collected offshore Evans Head. 8180 isotope data on planktonic foraminifera have been used to provide a chronological control on those cores collected from the western margin, to determine sediment accumulation rates and identify Late Quaternary isotopic stages, includingthe last glacial maximum (LGM) and the last interglacial (LIG). These same data are not available from other areas surveyed although sedimentation rates of about 1cm/kyr have been estimated from 14C data from the eastern continental margin sediments offshore Evans Head. The down-core total magnetic susceptibility profiles generally show similar patterns within each survey area. The magnetic susceptibility profiles for those cores from thewestern margin (Exmouth Plateau and Carnarvon Terrace) show relatively high valuesin the Holocene and around the LIG, and relatively low values during the LGM. Patterns of down-core variations in magnetic susceptibility could also be recognised in gravity cores from the eastern margin offshore Evans Head. Here, magnetic susceptibilities were relatively high around the LIG (similar to the western margin), but magnetic susceptibility were low in Holocene sediments, perhaps because of diagenetic remobilisation of iron in the core-tops. In general no distinct patterns are recognisable in the down-core magnetic susceptibility profiles from the southern margin. The down-core profiles of calcium carbonate from the west Australian continental margin show high values during the LGM, and minima in the Holocene and also during the LIG.Similarly, the down-core profile of calcium carbonate shows minimum values during the inferred LIG in eastern margin cores, although this interpretation is based on an approximate sedimentation rate. In general, total magnetic susceptibility is correlated with Al203, Si02 and Fe203, concentrations in sediments, indicating a control on magnetic susceptibility by terrigenous material contents. Calcium carbonate was found tobe a diluent for magnetic susceptibility in these continental margin sediments.

  • Australian estuaries and coastal waterways were classified into six subclasses according to the wave-, tide- and river-energies that shape them, and also according to their overall geomorphology. The geomorphic classification confirmed the energy classification. Within this framework: - 17% were classified as wave-dominated estuaries; - 11% were classified as tide-dominated estuaries; - 10% were classified as wave-dominated deltas; and - 9% were classified as tide-dominated deltas Therefore, only ~28% of Australian coastal waterways are actually estuaries. The remainder are delta's (19%), strandplains (~5%), or tidal creeks (~35%). A seventh subclass others (13%) includes: Drowned River Valleys, Embayments and Coastal Lakes/Lagoons/Creeks. Strandplains and Tidal Creeks are indicative of very low river-energy, and their joint dominance in the data set (~40%) reflects the fact that Australia is a dry continent, with relatively little river runoff by world standards.

  • This collection contains all national level bathymetry grids held by Geoscience Australia (GA) dating back to survey data obtained since 1993. <b>Value: </b>Bathymetry data is used for a wide range of marine applications including: navigation, environmental assessment, jurisdictional boundaries, resource exploration. <b>Scope: </b>Data holdings lying within the offshore area of Australia, including international waters. <b>To access the AusSeaBed Marine Data Portal</b> use the following link: <a href="https://portal.ga.gov.au/persona/marine#/">https://portal.ga.gov.au/persona/marine#/</a>

  • 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.

  • This dataset provides the spatially continuous data of seabed mud content (sediment fraction < 63 µm) expressed as a weight percentage ranging from 0 to 100%, presented in 0.01 decimal degree resolution raster format. The dataset covers the Australian continental EEZ, including seabed surrounding Tasmania. It does not include areas surrounding Macquarie Island, and the Australian Territories of Norfolk Island, Christmas Island, and Cocos (Keeling) Islands or Australia's marine jurisdiction off of the Territory of Heard and McDonald Islands and the Australian Antarctic Territory. This dataset supersedes previous predictions of sediment mud content for the Australian Margin 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 national and regional scales. The dataset may not be appropriate for use at local 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.

  • A statistical assessment of wave, tide, and river power was carried out using a database of 721 Australian clastic coastal depositional environments to test whether their geomorphology could be predicted from numerical values. The geomorphic classification of each environment (wave- and tide-dominated deltas, wave- and tide-dominated estuaries, lagoons, strand plains, and tidal flats) was established independently from remotely sensed imagery. To our knowledge, such a systematic numerical analysis has not been previously attempted for any region on earth.

  • 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.

  • The purpose of this investigation was to collate previously disparate information on near-pristine estuaries and make it widely available for use by managers, researchers, policy makers and the general public. This information was acquired through scientific articles, reports, conference proceedings, government agencies, grey literature, websites, expert advice and anecdotal observation and was summarised both on a state-by-state basis and at the national level, with emphasis on current knowledge and management.

  • Report to the National Oceans Office on the production of a consistent, high-quality bathymetric data grid and definition and description of geomorphic units for part of Australia's marine jurisdiction.