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  • In order to design a representative network of high seas marine protected areas (MPAs), an acceptable scheme is required to classify the benthic bioregions of the oceans. Given the lack of sufficient biological information to accomplish this task, we used a multivariate statistical method with 6 biophysical variables (depth, seabed slope, sediment thickness, primary production, bottom water dissolved oxygen and bottom temperature) to objectively classify the ocean floor into 11 different categories, comprised of 53,713 separate polygons, that we have termed "seascapes". Validation of the seascape classification was carried out by comparing the seascapes with an existing map of seafloor geomorphology, and by GIS analysis of the number of separate polygons and perimeter/area ratio. We conclude that seascapes, derived using a multivariate statistical approach, are biophysically meaningful subdivisions of the ocean floor and can be expected to contain different biological associations, in as much as different geomorphological units do the same. Our study illustrates how the identification of potential sites for high seas marine protected areas can be accomplished by GIS analysis of seafloor geomorphic and seascape classification maps. Using this approach, maps of seascape and geomorphic heterogeneity were generated in which heterogeneity hot-spots identify themselves as MPA candidates. The use of computer-aided mapping tools removes subjectivity in the MPA design process and provides greater confidence to stakeholders that an unbiased result has been achieved.

  • Selected geomorphic features and sedimentary facies were mapped in 283 of Australia's wave- and tide-dominated estuaries and deltas to quantitatively evaluate established evolutionary facies models that depict the evolution of estuaries into deltas during stable sea level conditions. While diagnostic facies for wave- and tide-dominated estuaries and deltas approximate those specified by the models, statistical analyses of the data also reveal two additional insights regarding the evolution of estuaries to deltas. First, there is an offshore shift in the locus of sand accumulation between tide-dominated estuaries and deltas, associated with the onset of delta development. Second, the mean surface area of intertidal environments (i.e., intertidal flats, mangroves/melaleuca, saltmarsh/salt flat facies) is greater in wave-dominated deltas than in wave-dominated estuaries. Tidal penetration associated with the river establishing a more direct and permanent connection to the sea during late-stage development presents a natural impediment to continued formation of an alluvial plain and full development of the 'classic' wave-dominated delta morphology. A notional evolutionary pathway for wave-dominated estuaries is developed from the distribution of facies that predicts the rate and susceptibility of geomorphic and habitat changes. The 'classic' deltaic geomorphology may be unattainable for wave-dominated systems, except those with significant terrigenous sediment inputs. Our study is the first published example of geomorphic and sedimentary data assembled from a large number of wave- and tide-dominated estuaries and deltas across an entire continent.

  • Simple, conceptual geomorphic models can assist environmental managers in making informed decisions regarding management of the coast at continental and regional scales. This basic information, detected from aerial photographs and/or satellite images, can be used to ascertain the relative significance of several common environmental issues, including: sediment trapping efficiency, turbidity, water circulation, and habitat change due to sedimentation for different types of clastic coastal depositional environments.

  • The benthic (sea floor) component of the National Marine Bioregionalisation covers the 80% of Australia's Exclusive Economic Zone that lies beyond the continental shelf break. It provides a description of patterns of biological distributions and physical habitats on the seafloor. The Benthic Bioregionalisation Report is a technical document describing how the benthic bioregions were created. It includes descriptions of all the datasets used, details of each bioregion, and examples of how the physical data may be used to sub-divide the marine bioregions for management. An evaluation of the benthic bioregionalisation including strengths, weaknesses and future work is also contained in the report.

  • 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.

  • Map produced by LOSAMBA for ACMA showing approx position of the proposed PIPE International PPC-1 Sydney - Guam Cable, issue2 DRAFT of February 2008 and issue4 of July 2008, in relation to the EEZs and Continental Shelf claims of Australia and adjoining countries until the cable finally leaves Australian areas approx 300nm north of Mellish Reef. Also shows Sydney Protection Zones as very small areas on this very small scale map. Not for sale or distribution. Contains Commercial in Confidence data. For internal use by ACMA only.

  • 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.

  • 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.

  • 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.

  • <p>The Australian Stratigraphic Units Database (ASUD) is the national authority on stratigraphic names in Australia. It originated as the National Register of Stratigraphic Names in 1949. The register was originally set up to help geoscientists adhere to the then newly created Australian Code of Stratigraphic Nomenclature (Lenz, et al, 1996). All information was held in a card file system until 1979 when the database was first developed electronically. The database now records information on all Australian stratigraphic units and their usage in published literature. <p>The database contains about 17500 currently approved stratigraphic names and over 36000 variations, most of which are superseded, obsolete, or misspelt versions of the current names. This information is based on over 16000 published references. <p>The database is maintained by Geoscience Australia on behalf of the Australian Stratigraphy Commission, a standing committee of the Geological Society of Australia. <p>Procedures can be queried at: http://www.ga.gov.au/data-pubs/datastandards/stratigraphic-units? <p>Data can be queried and downloaded at the ASUD website at: https://asud.ga.gov.au/ <p>Email contact: stratnames@ga.gov.au