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  • Geoscience Australia carried out a marine survey on Carnarvon shelf (WA) in 2008 (SOL4769) to map seabed bathymetry and characterise benthic environments through colocated sampling of surface sediments and infauna, observation of benthic habitats using underwater towed video and stills photography, and measurement of ocean tides and wavegenerated currents. Data and samples were acquired using the Australian Institute of Marine Science (AIMS) Research Vessel Solander. Bathymetric mapping, sampling and video transects were completed in three survey areas that extended seaward from Ningaloo Reef to the shelf edge, including: Mandu Creek (80 sq km); Point Cloates (281 sq km), and; Gnaraloo (321 sq km). Additional bathymetric mapping (but no sampling or video) was completed between Mandu creek and Point Cloates, covering 277 sq km and north of Mandu Creek, covering 79 sq km. Two oceanographic moorings were deployed in the Point Cloates survey area. The survey also mapped and sampled an area to the northeast of the Muiron Islands covering 52 sq km. cloates_3m is an ArcINFO grid of Point Cloates of Carnarvon Shelf survey area produced from the processed EM3002 bathymetry data using the CARIS HIPS and SIPS software

  • 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.

  • From 10 to 17 April 1997, the Australian Geological Survey Organisation (AGSO) chartered the 85 m Research Vessel Melville from Scripps Institution of Oceanography on a cooperative scientific basis, to map the sea bed east and northeast of Tasmania including the deep water part of the Gippsland Basin. The vessel was equipped with the SeaBeam 2000 multibeam sonar system, capable of swath-mapping the morphology and roughness of the sea bed in a swath 3.5 times as wide as the water depth. The central beam gave a 12 kHz bathymetric profile. Other equipment employed included a magnetometer and gravity meter. Navigation, by military standard GPS using the P code, had an accuracy of about 5 m. Detailed ship's tracks for the survey, from south to north, are shown in Figures 2-5. The aims of the cruise were to determine the morphology and sea bed character of selected areas, to aid in tectonic, basin and sedimentological studies, to aid the fishing industry, and to provide critical information for future seismic profiling and geological sampling. Satellite gravity images, and sparse bathymetric and seismic profiles, were used to plan the survey.

  • 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.

  • Geoscience Australia carried out marine surveys in Jervis Bay (NSW) in 2007, 2008 and 2009 (GA303, GA305, GA309, GA312) to map seabed bathymetry and characterise benthic environments through colocated sampling of surface sediments (for textural and biogeochemical analysis) and infauna, observation of benthic habitats using underwater towed video and stills photography, and measurement of ocean tides and wavegenerated currents. Data and samples were acquired using the Defence Science and Technology Organisation (DSTO) Research Vessel Kimbla. Bathymetric mapping, sampling and tide/wave measurement were concentrated in a 3x5 km survey grid (named Darling Road Grid, DRG) within the southern part of the Jervis Bay, incorporating the bay entrance. Additional sampling and stills photography plus bathymetric mapping along transits was undertaken at representative habitat types outside the DRG. jb_s1 is an ArcINFO grid of southern part of Jervis Bay survey area (south1 is part of Darling RD grid) produced from the processed EM3002 bathymetry data using the CARIS HIPS and SIPS software

  • Ausgeo News Article for the release of the Australian Bathymetry and Topography Grid June 2009

  • Several scenarios of an original 3D model based on the petroleum systems model of Fuji et al. (APPEA 2004) were simulated using the PetroMod 3D V.10 modeling software. In general the results of the modelling study presented here confirms the modelling results of Fuji et al. (2004) with respect to the timing of generation in the different sub-basins as well as present day maturity. The main differences between the work of Fuji et al. (2004) and the work presented here are based on the use of PhaseKinetic models for the individual source rock formations and the ensuing compositional predictions of the fluids in different fields. Source rock transformation ratios as well as the bulk generation rates indicate that the source rocks are presently still generating. The Central Swan Graben area is presently more mature than the other kitchen area of the Vulcan Sub-basin, the Cartier Trough. The locations of predicted accumulations coincide with the locations of most of the proven fields. In many cases accumulation sizes and predicted column heights are large, mainly due to the fact that the resolution of the numerical model is low which leaves rather large volumes of the cells to be filled. Modelling results predict a series of accumulations at locations which have, as yet, not been tested. However, most of them depend on fault closure, thus increasing exploration risk. The main risks as observed from this modelling exercise are: 1) source rock presence and definition, 2) definition of the traps, 3) resolution of the input model, 4) cap rock properties, which are still largely unconstrained. The different scenarios modelled show distinct variations with respect to predicted petroleum distribution as well as the physical properties of the accumulated fluids.

  • Much of the deep sea encompasses soft-sediment plains, with very few hard substrates for invertebrates to colonise. At first glance, these habitats seem barren, but they are actually teeming with life. Compared to organisms from shallow water, many animals here are quite small. In addition, most of the animals are infaunal, meaning they live within the sediment. During feeding and burrowing, these animals form a range of features called lebensspuren, defined as any type of sedimentary structure produced by a living organism. Sampling deep sea animals can be a challenge, and traditional methods of grabs and boxcores provide only a single snapshot of a small area to characterise broad regions. Underwater imagery facilitates the characterisation of biological communities over a larger area, but the quantification of biodiversity from video is often restricted to larger epifauna, thus reducing its utility to measure biodiversity in deep sea soft sediments where animals are often small or infaunal. High resolution still images provide an interesting avenue with which to quantify biological activity based on lebensspuren. In this study, we used thousands of still images taken along the edge of the Eastern and Western margins of Australia to identify and characterise deep-sea lebensppuren. The features identified were compiled into a Lebensspuren Directory (Section 7), and the data was used to correlate abiotic factors to lebensspuren and to valuate whether the quantification of lebensspuren from still photographs is an appropriate technique for broadly quantifying biological activity and diversity in the deep sea (Sections 2 - 6).