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  • 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.

  • 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.

  • 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.

  • The data set provides outlines for the maximum extent of geomorphic units for Australia's Exclusive Economic Zone, including the offshore island territories, but not the Australian Antarctic Territory. These data were compiled as part of Geoscience Australia's integrated digital information system to provide improved accessibility and knowledge relating to the environmental management of Australia's oceans resources. The geomorphic units are to be used as surrogates for benthic habitats and can be best applied to the construction of bioregionalisations of the seabed. The data set also includes the name of units in the attribute table, where known, the source(s) of the names, feature codes and province codes as well as the area and perimeter of each unit. The data are accompanied by Geoscience Australia Record 2003/30. Updated October 2006.

  • Geoscience Australia and the National Oceans Office carried out a joint project to produce a consistent, high-quality 9 arc second (0.0025° or ~250m at the equator) bathymetric data grid of those parts of the Australian water column jurisdiction lying between 92º E and 172º E and 8 º S and 60º S. As well as the waters adjacent the continent of Australia and Tasmania, the area selected also covers the area of water column jurisdiction surrounding Macquarie Island, and the Australian Territories of Norfolk Island, Christmas Island, and Cocos (Keeling) Islands. The area selected does not include Australia's marine jurisdiction off the Territory of Heard and McDonald Islands and the Australian Antarctic Territory.

  • The Corporate Archive consists of deposited copies of all internal publications and documents of the agency and its predecessors: the Bureau of Mineral Resources, Australian Geological Survey Organisation and those which have merged with it over the years, such as AUSLIG. These include unique material such as field notebooks and a small quantity of manuscripts. Unrestricted items in this collection are currently being digitised to improve access

  • Australia is an island continenet extending from tropical to midlatitude waters with an Exclusive Economic Zone of some 8.6 million square kilometres. Its regional seas are exposed to climatological conditions ranging from the westerly Roaring Forties winds in the south, to monsoon and tropical cyclone conditions in the north. It also encompasses regions of extreme biodiversity, with 80 percent of southern temperate species endemic to the region. The focus of marine research in Australia is becoming more interdisciplinary in response to factors such as the national government's recent Oceans Policy, which emphasises sustainable development and ecological based management. However, historically there have been relatevely few major interdisciplinary studies in Australian waters.

  • 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.

  • 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.

  • This report describes the iterative methods used to create the seascapes, including a detailed appendix documenting the different datasets used in the different planning zones. Creating the seascapes is necessarily an iterative process whereby the available datasets are combined in different combinations, or added as they become available, using an unsupervised 'crisp' ISOClass classification in ERMapper. In each classification only biophysical properties that have consistent and definable relationships with the benthic biota and are known in sufficient detail across Australia's entire marine region are used to create the seascapes. An initial validation of the classification technique has been undertaken on a subset of the data for the shelf surrounding Tasmania using an alternative unsupervised 'fuzzy' classification. Results of this validation indicate that the unsupervised classification methodology provides consistent and reliable classes for defining the seascapes.