The basin geomorphic feature layer represents the spatial extent of the basins of the worlds oceans based on interpretation of the SRTM30 plus v7 global bathymetry model. The layer is one of the 25 layers that make up the global seafloor geomorphic features map (Harris et.al. 2014). Basins are “a depression, in the sea floor, more or less equidimensional in plan and of variable extent”(IHO, 2008). In this study basins are restricted to seafloor depressions that are defined by closed bathymetric contours. Basins were mapped based on the identification of the most shoal, closed, bathymetric contours, examined regionally for the major ocean basins and shelf seas.