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  • 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 datset comprises chlorophyll a, b and c and phaeophytin a concentrations from the upper 2 cm of seabed sediments. 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).

  • On the Australian margin, submarine canyons have formed along all sides of the continent and are exposed to the potential influence of large-scale ocean currents, including the Leeuwin Current and the East Australian Current. Recognised in marine bioregional plans as potential biodiversity hotspots, many of these canyons sit within the new national network of Commonwealth Marine Reserves. This GIS polygon layer contains 753 submarine canyons along the Australian continental margin and external territorie, mapped from a range of bathymetry datasets. The layer has attributes describing the canyon's geophysical characteristics. The definitions are as follows. SHAPE_Leng: Perimeter (km) SHAPE_Area: Planar area (km2) centreli_L: Centreline length (km); total length of canyon/sub-canyons centreline(s) MBG_Width: Minimum bounding rectangle width (km) MBG_Length: Minimum bounding rectangle length (km) MBG_Orient: Minimum bounding rectangle orientation len_wid_ra: Length to width ratio; a measure of elongation; larger the value the more elongate the canyon border_ind: Border index; a measure of geometric complexity; larger he value the more fractal the canyon compactnes: a measure of compactness; larger the value the more compact the canyon (or the smaller its border) no_branch: Number of sub-canyons head_incis: Head incision (m); incision deph of canyon head head_depth: Head depth (m); water depth of canyon head foot_depth: Foot depth (m); water depth of canyon foot depth_rang: Depth range (m); depth range between canyon head and foot slope_mean: Slope mean; average slope gradients within canyon polygon slope_std: Slope standard deviation; standard deviation of the slope gradients within canyon polygon slope_rang: Slope range; range between maximum and minimum slope gradients within canyon polygon surArea1: Surface area (km2); 3-D surface area of canyon rugosity: Rugosity; roughness of canyon surface volume: Volume (km3); 3-D volume enclosed by the canyon bottom and walls head_x: X coordinate of canyon head; in Asia south Equidistant Conic projection head_y: Y coordinate of canyon head; in Asia south Equidistant Conic projection foot_x: X coordinate of canyon foot; in Asia south Equidistant Conic projection foot_y: Y coordinate of canyon foot; in Asia south Equidistant Conic projection h_f_dist: Head to foot distance (km); euclidian distance between canyon head and foot h_f_slope: head to foot slope; slope gradient between canyon head and foot dist_shelf: Distance to shelf (km); euclidian distance of canyon to shelf break; a distance of zero indicates that canyon touchs or intersects the shelf break or within the continental shelf near_canyo: Nearest canyon (km); euclidian distance to the nearest canyon dist_coast: Distance to coast (km); euclidian distance of canyon to Australian coast focal_var: Focal variety; number of neighbouring canyons within a nominated proximity inci_depth: Incision depth (m); averged depth of canyon area that incises into shelf break; slope-confined canyons have values of zero inci_area: Incision area (km2) ; area of canyon area that incises into shelf break; slope-confined canyons have values of zero slope15: Percentage of slope gradient greater than 15 degree; percentage of canyon area with slope gradients greater than 15 degree sinuosity: a measure of sinuosity; larger the value the more sinuous the canyon shelf_inci: Shelf incision; shlef-incising canyons have value of 1; slope-confined canyons have value of zero dist_river: Distance to revier (km); euclidian distance to the mouth of the nearest permanent river uncertain: Uncertainty; mapping uncertainty assigned to canyon; larger the value the more uncertain the mapping is marine_reg: Marine region; the location of the canyon in one of the marine regions canyon_nam: The name of canyon if known map_region: Map region; the location of canyon in one of the map regions Please refer to Marine Geology 357, 362-383 for details of mapping methods.

  • The grid was created from the Australian bathymetry and topography grid (2009, version 4). The data represents the degree of aspect of a slope surface (a rectangle of 3 by 3 cells).

  • The grid was created from the Australian bathymetry and topography grid (2009, version 4). The data represents the degree of slope of an area of seabed (a rectangle of 3 by 3 cells).

  • The grid was created from the Australian bathymetry and topography grid (2009, version 4). The data represents the difference in elevation between the highest and lowest point within a specified area (a rectangle of 3 by 3 cells). The units are metres.

  • This dataset provides the spatially continuous data of predicted seabed mud content (sediment fraction finer than 63 µm) expressed as a weight percentage ranging from 0 to 100%, presented in 0.0025 decimal degree (dd) resolution raster grids format and an ascii text file. The dataset covers the north-northwest region of the Australian continental EEZ. This dataset supersedes previous predictions of seabed mud content for the region with demonstrated improvements in accuracy. Accuracy of predictions varies based on density of underlying data and level of seabed complexity. Artefacts occur in this dataset as a result of insufficient samples in relevant areas. This dataset is intended for use at regional scale. The dataset may not be appropriate for use at local scales in areas where sample density is insufficient to detect local variation in sediment properties. To obtain the most accurate interpretation of sediment distribution in these areas, it is recommended that additional samples be collected and interpolations updated.

  • New mapping by Geoscience Australia has identified 713 submarine canyons on the Australian margin and an additional 40 within external territorial seas. Ninety-five canyons are classified as shelf-incising and the remainders are located on the continental slope and classed as blind canyons. A range of metrics were derived to describe canyon form and distribution and used to identify morphologically unique canyons. This poster illustrates this dataset in the context of the national network of Commonwealth Marine Reserves.

  • This resource contains bathymetry and backscatter 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). The survey used a Kongsberg EM3002 300 kHz multibeam sonar system mounted in single head configuration to map four areas, covering a combined area of 507 square kilometres. Data are gridded to 2 m spatial resolution. 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 et al. 2013).<p><p>This dataset is not to be used for navigational purposes.

  • This resource contains multibeam sonar bathymetry data for the continental shelf area of Flinders Commonwealth Marine Reserve, northeast Tasmania. Multibeam data were collected by Geoscience Australia and University of Tasmania in May 2011 (survey GA0331) and June-July 2012 (survey GA0337) on RV Challenger. The survey used a Kongsberg EM3002 300 kHz multibeam sonar system mounted in single head configuration to broadly classify the seabed into hard (bedrock reef), soft (sedimentary) and mixed substrate types at select locations across the shelf. The 2011 survey involved reconnaissance mapping along a series of cross-shelf transects, covering a total of 767 line km. For the 2012 survey, multibeam data (bathymetry and backscatter) were collected at 40 pre-determined stations, each covering an area approximately 200 x 200 m. The location of stations was selected using a Generalised Random Tessellation Stratified (GRTS) sampling design that ensured an even spatial distribution of sites. Multibeam data was also collected along transits between GRTS stations (410 line km) and across a 30 km2 area of the outer shelf, incorporating areas of low profile reef, sandy shelf and three shelf-incising canyon heads. Bathymetry data are gridded to 2 m spatial resolution. The 2012 survey also included seabed observations at the 40 GRTS stations using a drop camera and collection of sediment samples at 31 stations using a Shipek grab. The Flinders CMR survey was a pilot study undertaken in 2012 as part of the National Marine Biodiversity Hub's National Monitoring Evaluation and Reporting Theme. The aim of this theme is to develop a blueprint for the sustained monitoring of the South-east Commonwealth Marine Reserve Network, specifically; 1) to contribute to an inventory of demersal and epibenthic conservation values in the reserve and 2) to test methodologies and deployment strategies in order to inform future survey design efforts. Several gear types were deployed; including multibeam sonar, shallow-water (less than 150m) Baited Remote Underwater Video Systems (BRUVS), deep- water BRUVS (to 600 m), towed video and digital stereo stills. Embargo statement: Resource embargoed pending completion of NERP research. Release date 31 December 2014. Attribution statement: Data was sourced from the NERP Marine Biodiversity Hub. The Marine Biodiversity Hub is supported through funding from the Australian Government's National Environmental Research Program (NERP), administered by the Department of Sustainability, Environment, Water, Population and Communities (DSEWPAC). Dataset name: National Environmental Research Program (NERP) Marine Biodiversity Hub, 2012, Flinders Commonwealth Marine Reserve Shelf Backscatter

  • 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 bulk organic carbon and nitrogen concentrations (and isotopes) from 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).