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  • This service has been created specifically for display in the National Map and the chosen symbology may not suit other mapping applications. The Australian Topographic web map service is seamless national dataset coverage for the whole of Australia. These data are best suited to graphical applications. These data may vary greatly in quality depending on the method of capture and digitising specifications in place at the time of capture. The web map service portrays detailed graphic representation of features that appear on the Earth's surface. These features include the administration boundaries from the Geoscience Australia 250K Topographic Data, including state forest and reserves.

  • This resource contains geochemistry data for the Oceanic Shoals Commonwealth Marine Reserve (CMR) in the Timor Sea collected by Geoscience Australia during September and October 2012 on RV Solander (survey GA0339/SOL5650). This dataset comprises major and trace element concentrations in the upper 2 cm of seabed sediment. The Oceanic Shoals Commonwealth Marine Reserve survey was undertaken as an activity within the Australian Government's National Environmental Research Program Marine Biodiversity Hub and was the key component of Research Theme 4 - Regional Biodiversity Discovery to Support Marine Bioregional Plans. Hub partners involved in the survey included the Australian Institute of Marine Science, Geoscience Australia, the University of Western Australia, Museum Victoria and the Museum and Art Gallery of the Northern Territory. Data acquired during the survey included: multibeam sonar bathymetry and acoustic backscatter; sub-bottom acoustic profiles; physical samples of seabed sediments, infauna and epibenthic biota; towed underwater video and still camera observations of seabed habitats; baited video observations of demersal and pelagic fish, and; oceanographic measurements of the water column from CTD (conductivity, temperature, depth) casts and from deployment of sea surface drifters. Further information on the survey is available in the post-survey report published as Geoscience Australia Record 2013/38: Nichol, S.L., Howard, F.J.F., Kool, J., Stowar, M., Bouchet, P., Radke, L., Siwabessy, J., Przeslawski, R., Picard, K., Alvarez de Glasby, B., Colquhoun, J., Letessier, T. & Heyward, A. 2013. Oceanic Shoals Commonwealth Marine Reserve (Timor Sea) Biodiversity Survey: GA0339/SOL5650 - Post Survey Report. Record 2013/38. Geoscience Australia: Canberra. (GEOCAT #76658).

  • Geoscience Australia marine reconnaissance survey TAN0713 to the Lord Howe Rise offshore eastern Australia was completed as part of the Federal Government's Offshore Energy Security Program between 7 October and 22 November 2007 using the New Zealand Government's research vessel Tangaroa. The survey was designed to sample key, deep-sea environments on the east Australian margin (a relatively poorly-studied shelf region in terms of sedimentology and benthic habitats) to better define the Capel and Faust basins, which are two major sedimentary basins beneath the Lord Howe Rise. Samples recovered on the survey contribute to a better understanding of the geology of the basins and assist with an appraisal of their petroleum potential. They also add to the inventory of baseline data on deep-sea sediments in Australia. The principal scientific objectives of the survey were to: (1) characterise the physical properties of the seabed associated with the Capel and Faust basins and Gifford Guyot; (2) investigate the geological history of the Capel and Faust basins from a geophysical and geological perspective; and (3) characterise the abiotic and biotic relationships on an offshore submerged plateau, a seamount, and locations where fluid escape features were evident. This dataset comprises mineraology data (e.g. concentrations of bulk carbonate, calcite, aragonite, halite, quartz) from seanbed sediments (0-2cm). Some relevant publications which pertain to these datasets include: 1. Heap, A.D., Hughes, M., Anderson, T., Nichol, S., Hashimoto, T., Daniell, J., Przeslawski, R., Payne, D., Radke, L., and Shipboard Party, (2009). Seabed Environments and Subsurface Geology of the Capel and Faust basins and Gifford Guyot, Eastern Australia - post survey report. Geoscience Australia, Record 2009/22, 166pp. 2. Radke, L.C. Heap, A.D., Douglas, G., Nichol, S., Trafford, J., Li, J., and Przeslawski, R. 2011. A geochemical characterization of deep-sea floor sediments of the northern Lord Howe Rise. Deep Sea Research II 58: 909-921

  • GA Record detailing the bathymetry compilation put together by Geoscience Australia in agreement with the Australian Antarctic Division. The dataset was used in support of Australia's contribution to the development of the Representative System of Marine Protected Areas (RSMPA) at the CCAMLR Workshop on Marine Protected Areas, held in Brest, France in August 2011.

  • Inter-reefal (i.e. non-reefal) seabed environments have been much less studied than the coral reefs, however they comprise 95% of the total Great Barrier Reef (GBR) Marine Park area. Regional scale spatial analysis of the sediments and geomorphology in these areas allows for a systematic characterisation of the seabed, where comprehensive biological datasets are lacking. We offer an up-to-date synthesis of inter-reefal environments in the GBR, to better understand the nature and distribution of seabed habitats at a regional scale and within the current planning zone scheme, in support of Marine Park management. New quantitative information about surface sediments and geomorphic features, together comprise a new physical dataset of the GBR seabed. This regional dataset contains over 3,000 sediment samples available in Geoscience Australia's (GA) national marine samples database, MARS (www.ga.gov.au/oracle/mars), substantially improving the coverage of surface sediment data from inter-reefal areas, and; GA's current Geomorphic Features dataset (Harris et al., 2005) of the seabed morphology. This marks the first regional synthesis of the surface sedimentology and geomorphology of the GBR since the pioneering work of Belperio (1983a, 1983b) and Maxwell (1968; 1969a; 1969b; 1973). We present a new quantitative sediment dataset that shows regional trends in surface sediments; refining the existing facies model for the mixed carbonate-siliciclastic GBR margin. Our findings also reveal local scale facies characteristics, within the broader regional trends. Until now these distribution patterns haven't been identified on the GBR shelf and are considered to be an important characteristic of the region. In addition, we have revealed other sedimentary characteristics of the region; - Low gravel concentrations cover extensive parts of the shelf. Patches of high gravel concentration occur locally on parts of the inner and outer shelves, reflecting the input of gravel from reef talus aprons. These areas may also be associated with strong tidal currents. - Sand is the dominant grain size fraction, and highest concentrations occur on the middle and outer shelves. Although continuous regions of high sand concentration occur in the far north (e.g. Cape York) and south (e.g. south of Broad Sound) of the Marine Park, the overall distribution of sand is variable as changes in concentration produce local, small-dimension patches at a scale of 10's of metres. - The patchy distribution of sand may reflect a mixture of; 1) widespread supply of modern skeletal carbonate grains, such as foraminifera, molluscs and Halimeda, and/or restricted supply of relict sand; and, 2) the effects of hydrodynamic irregularities in inter-reef channels. - High mud concentrations predominantly occur along the inner shelf and slope. Mud forms local patches on the inner shelf associated with fluvial point sources, which are spatially discontinuous, producing a regionally variable terrigenous sediment wedge of coalescing mud (and sand) patches. - Surface sediments are carbonate-dominated across the shelf and broadly display a regional north-south, shelf-parallel zonation pattern. Low carbonate concentrations of <40% on the inner shelf denote high terrigenous compositions, which increase to >80% on the outer shelf. Within the regional zonation pattern, carbonate patches locally produce a variable distribution in sediment composition. - Uniformly high concentrations of bulk carbonate and carbonate mud on the outer shelf, reflect the constant supply of skeletal carbonate grains from inter-reefal environments, in areas of high reef density and the negligible influence of fluvial sediments on the outer shelf. Regional variations in seabed sediments and geomorphology across the region are also evident in the physical character of the planning zones.

  • This study demonstrates that seabed topography and geodiversity play key roles in controlling the spatial dynamics of large fish predators over macro-ecological scales. We compiled ten years of commercial fishing records from the Sea Around Us Project and developed continental-scale catch models for an assemblage of large open-water fish (e.g. tuna, marlins, mackerels) for Western Australia. We standardised catch rates to account for the confounding effects of year, gear type and species body mass using generalised linear models, from which relative indices of abundance were extracted. We combined these with an extensive array of geophysical, oceanographic, biological, and anthropogenic data to (1) map the location of pelagic hotspots and (2) determine their most likely mechanistic drivers. We tested whether submarine canyons promote the aggregation of pelagic fish, and whether geomorphometrics (measures of seafloor complexity) represent useful surrogate indicators of their numbers. We also compared predicted fish distributions with the Australian network of Commonwealth Marine Reserves to assess its potential to provide conservation benefits for highly mobile predators. Both static and dynamic habitat features explained the observed patterns in relative abundance of pelagic fish. Geomorphometrics alone captured more than 50% of the variance, and submarine canyon presence ranked as the most influential variable in the North bioregion. Seafloor rugosity and fractal dimension, salinity, ocean energy, current strength, and human use were also identified as important predictors. The spatial overlap between fish hotspots and marine reserves was very limited in most parts of the EEZ, with high-abundance areas being primarily found in multiple use zones where human activities are subject to few restrictions.

  • The Lord Howe Island survey SS06-2008 in April 2008 aboard the RV Southern Surveyor was a collaboration between the University of Wollongong and Geoscience Australia. The survey was also an activity of the Commonwealth Environment Research Facilities' (CERF) Marine Biodiversity Hub, of which Geoscience Australia is a partner, and will contribute to the revised Plan of Management for the Lord Howe Marine Parks. The objectives of the survey were to map the morphology and benthic environments of the shallow shelf that surrounds Lord Howe Island as well as the deeper flanks of this largely submarine volcano. Of particular interest was the apparent drowned reef structure on the shelf and the spatial distribution of seabed habitats and infauna. The data collected are required to better understand the history of reef growth at Lord Howe Island, which sits at the southernmost limit of reef formation, and links between the physical environment and ecological processes that control the spatial distribution of biodiversity on the shelf. The morphology of the flanks of the submarine volcano was also examined to reveal whether they provide evidence of major erosional and depositional processes acting on the volcano. This report provides a description of the survey activities and the results of the processing and initial analysis of the data and samples collected.

  • The identification of suitable abiotic surrogates for biological diversity requires the collection of both physical and biological data. However, logistical constraints often preclude experimental designs that incorporate spatial and temporal replication. Given the quite limited resources normally available for surveys, the investigation of appropriate surrogates involves a trade-off between overall spatial coverage and replication. We have completed a survey in Jervis Bay in which environmental and infaunal data were collected contemporaneously in order to be combined with similar data from a previous winter survey (survey number GA309) to investigate variation across seasons. Because there will be a certain error in sampling at the exact location as the previous survey, the survey design also required that replicate samples be taken at a set number of stations in order to investigate fine-scale variability (at the scale of metres). We used grabs to collect paired geochemical and biological samples from thirty-two stations in a defined grid near Darling Rd; at eight of these stations we deployed three pairs of grabs to investigate fine-scale variability. Due to good weather and extra ship time available, we also deployed a CTD to investigate vertical temperature and salinity profiles at each station in the Darling Rd grid, as well as at stations throughout the entire bay. Samples are expected to be processed and analysed by late 2009, but preliminary results indicate that most physical variables and infaunal assemblages varied between seasons. In addition, variation among infaunal assemblages seems greater among stations (hundreds of meters) than within replicates at stations (meters).

  • The Timor Sea and its tropical marine environment support significant and growing economic activity including oil and gas exploration. To reduce uncertainty in decision making regarding the sustainable use and ongoing protection of these marine resources, environmental managers and resource users require sound scientific information on the composition and stability of seabed environments and their biological assemblages. Surveys SOL4934 and SOL5117 to the eastern Joseph Bonaparte Gulf were undertaken in August and September 2009 and July and August 2010 respectively, in collaboration with the Australian Institute of Marine Science, with research collaborations from the RAN Australian Hydrographic Office, the Geological Survey of Canada and the Museum and Art Gallery of the Northern Territory. The purpose of these surveys were to develop biophysical maps, and deliver data and information products pertaining to complex seabed environment of the Van Diemen Rise and identify potential geohazards and unique, sensitive environments that relate to offshore infrastructure. This dataset comprises four P pools in the upper 2 cm of the fine fraction (<63 um) of seabed sediments:adsorbed/oxide-associated-P; authigenic-P; detrital-P and organic-P. Some relevant publications are listed below: 1. Heap, A.D., Przeslawski, R., Radke, L., Trafford, J., Battershill, C. and Shipboard Party. 2010. Seabed environments of the eastern Joseph Bonaparte Gulf, Northern Australia: SOL4934 Post Survey Report. Geoscience Australia Record 2010/09, pp.81. 2. Anderson, T.J., Nichol, S., Radke, L., Heap, A.D., Battershill, C., Hughes, M., Siwabessy, P.J., Barrie, V., Alvarez de Glasby, B., Tran, M., Daniell, J. & Shipboard Party, 2011b. Seabed Environments of the Eastern Joseph Bonaparte Gulf, Northern Australia: GA0325/Sol5117 - Post-Survey Report. Geoscience Australia, Record 2011/08, 58pp. 3. Radke, L.C., Li, J., Douglas, G., Przeslawski, R., Nichol, S, Siwabessy, J., Huang, Z., Trafford, J., Watson, T. and Whiteway, T. Characterising sediments of a tropical sediment-starved continental shelf using cluster analysis of physical and geochemical variables. Environmental Chemistry, in press

  • 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.