National Submarine Canyons of Australia

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 orientationlen_wid_ra: Length to width ratio; a measure of elongation; larger the value the more elongate the canyonborder_ind: Border index; a measure of geometric complexity; larger he value the more fractal the canyoncompactnes: a measure of compactness; larger the value the more compact the canyon (or the smaller its border)no_branch: Number of sub-canyonshead_incis: Head incision (m); incision deph of canyon headhead_depth: Head depth (m); water depth of canyon headfoot_depth: Foot depth (m); water depth of canyon footdepth_rang: Depth range (m); depth range between canyon head and footslope_mean: Slope mean; average slope gradients within canyon polygonslope_std: Slope standard deviation; standard deviation of the slope gradients within canyon polygonslope_rang: Slope range; range between maximum and minimum slope gradients within canyon polygonsurArea1: Surface area (km2); 3-D surface area of canyonrugosity: Rugosity; roughness of canyon surfacevolume: Volume (km3); 3-D volume enclosed by the canyon bottom and wallshead_x: X coordinate of canyon head; in Asia south Equidistant Conic projectionhead_y: Y coordinate of canyon head; in Asia south Equidistant Conic projectionfoot_x: X coordinate of canyon foot; in Asia south Equidistant Conic projectionfoot_y: Y coordinate of canyon foot; in Asia south Equidistant Conic projectionh_f_dist: Head to foot distance (km); euclidian distance between canyon head and footh_f_slope: head to foot slope; slope gradient between canyon head and footdist_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 shelfnear_canyo: Nearest canyon (km); euclidian distance to the nearest canyondist_coast: Distance to coast (km); euclidian distance of canyon to Australian coastfocal_var: Focal variety; number of neighbouring canyons within a nominated proximityinci_depth: Incision depth (m); averged depth of canyon area that incises into shelf break; slope-confined canyons have values of zeroinci_area: Incision area (km2) ; area of canyon area that incises into shelf break; slope-confined canyons have values of zeroslope15: Percentage of slope gradient greater than 15 degree; percentage of canyon area with slope gradients greater than 15 degreesinuosity: a measure of sinuosity; larger the value the more sinuous the canyonshelf_inci: Shelf incision; shlef-incising canyons have value of 1; slope-confined canyons have value of zerodist_river: Distance to revier (km); euclidian distance to the mouth of the nearest permanent riveruncertain: Uncertainty; mapping uncertainty assigned to canyon; larger the value the more uncertain the mapping ismarine_reg: Marine region; the location of the canyon in one of the marine regionscanyon_nam: The name of canyon if knownmap_region: Map region; the location of canyon in one of the map regionsPlease refer to Marine Geology 357, 362-383 for details of mapping methods.