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  • ArcGIS shapefile detailing GA's multibeam bathymetry holdings and coverage.

  • The Queen Charlotte Fault (QCF) off western Canada is the northern equivalent to the San Andreas Pacific - America boundary. Geomorphology and surface processes associated with the QCF system have been revealed in unprecedented detail by recent seabed mapping surveys. The QCF bisects the continental shelf of British Columbia forming a fault-valley that is visible in multibeam sonar bathymetry data. The occurrence of the fault within a valley, and its association with what appear to be graben structures, suggest the fault may exhibit minor rifting (extension) as well as strike-slip motions in the region offshore from Haida Gwaii (Queen Charlotte Islands). Fault-valley formation, slumping and stranding of submarine canyon thalwegs are geomorphic expressions of QCF tectonism, illustrating the general applications of multibeam technology to marine geophysical research.

  • The legacy of multiple marine transgressions is preserved in a complex morphology of ridges, mounds and reefs on the Carnarvon continental shelf, Western Australia. High-resolution multibeam sonar mapping, underwater photography and sampling across a 280 km2 area seaward of the Ningaloo Coast World Heritage Area shows that these raised features provide hardground habitat for modern coral and sponge communities. Prominent among these features is a 20 m high and 15 km long shore-parallel ridge at 60 m water depth. This ridge preserves the largely unaltered form of a fringing reef and is interpreted as the predecessor to modern Ningaloo Reef. Landward of the drowned reef, the inner shelf is covered by hundreds of mounds (bommies) up to 5 m high and linear ridges up to 1.5 km long and 16 m high. The ridges are uniformly oriented to the north-northeast and several converge at their landward limit. On the basis of their shape and alignment, these ridges are interpreted as relict long-walled parabolic dunes. Their preservation is attributed to cementation of calcareous sands to form aeolianite, prior to the post-glacial marine transgression. Some dune ridges abut areas of reef that rise to sea level and are highly irregular in outline but maintain a broad shore-parallel trend. These are tentatively interpreted as Last Interglacial in age. The mid-shelf and outer shelf are mostly sediment covered with relatively low densities of epibenthic biota and have patches of low-profile ridges that may also be relict reef shorelines. An evolutionary model for the Carnarvon shelf is proposed that relates the formation of drowned fringing reefs and aeolian dunes to Late Quaternary eustatic sea level.

  • In December 2010, the Northern Territory Government (NTG) announced funding for high priority environmental monitoring and research activities in Darwin Harbour. Following the announcement, the Darwin Harbour Habitat Mapping Program was developed and managed by the Department of Land Resource Management (DLRM). Under the Program, DLRM collaborated with GA, the Australian Institute of Marine Science (AIMS), and the Darwin Port Corporation to undertake multibeam and backscatter data acquisition for the Darwin Harbour. This flythough presents seabed bathymetry compilations for the Darwin Harbour in the Northern Territory. These videos are intended for potential public release. The overall objective of the INPEX Environmental Offset program `Mapping Marine and Estuarine Benthic Habitats in Darwin and Bynoe harbours is to improve knowledge of the marine habitats in the Darwin and Bynoe harbours region by producing thematic habitat maps to underpin marine resource management decisions.

  • Please note: This product has been superseded by 50m Multibeam Dataset of Australia 2018. - This tile contains all multibeam data held by Geoscience Australia on August 2012 within the specified area. The data has been gridded to 50m resolution. Some deeper data has also been interpolated within the mapped area. The image provided can be viewed on the free software CARIS Easyview, available from the CARIS website: www.caris.com under Free Downloads.

  • Please note: This product has been superseded by 50m Multibeam Dataset of Australia 2018. - This tile contains all multibeam data held by Geoscience Australia on August 2012 within the specified area. The data has been gridded to 50m resolution. Some deeper data has also been interpolated within the mapped area. The image provided can be viewed on the free software CARIS Easyview, available from the CARIS website: www.caris.com under Free Downloads.

  • Please note: This product has been superseded by 50m Multibeam Dataset of Australia 2018. - This tile contains all multibeam data held by Geoscience Australia on August 2012 within the specified area. The data has been gridded to 50m resolution. Some deeper data has also been interpolated within the mapped area. The image provided can be viewed on the free software CARIS Easyview, available from the CARIS website: www.caris.com under Free Downloads.

  • Please note: This product has been superseded by 50m Multibeam Dataset of Australia 2018. - This tile contains all multibeam data held by Geoscience Australia on August 2012 within the specified area. The data has been gridded to 50m resolution. Some deeper data has also been interpolated within the mapped area. The image provided can be viewed on the free software CARIS Easyview, available from the CARIS website: www.caris.com under Free Downloads.

  • Please note: This product has been superseded by 50m Multibeam Dataset of Australia 2018. - This tile contains all multibeam data held by Geoscience Australia on August 2012 within the specified area. The data has been gridded to 50m resolution. Some deeper data has also been interpolated within the mapped area. The image provided can be viewed on the free software CARIS Easyview, available from the CARIS website: www.caris.com under Free Downloads.

  • Please note: This product has been superseded by 50m Multibeam Dataset of Australia 2018. - This tile contains all multibeam data held by Geoscience Australia on August 2012 within the specified area. The data has been gridded to 50m resolution. Some deeper data has also been interpolated within the mapped area. The image provided can be viewed on the free software CARIS Easyview, available from the CARIS website: www.caris.com under Free Downloads.