Summary: | To provide an improved mapping of the seafloor fabric globally, we have used available sounding data along with an improved global marine gravity model to develop at grid at 15 arcsecond resolution (~500 m). Land elevations are based on the best available data from SRTM, ASTER digital elevation models while the ice topography of Greenland and Antarctica is based on CryoSat-2 and IceSat. Ocean bathymetry is based on bathymetric predictions from the latest global gravity model from CryoSat-2 and Jason-1 along with 494 million carefully edited depth soundings at 15 arcsecond resolution. Bathymetry of the Arctic seafloor is based on the IBCAO grid with improved resolution in areas of multibeam coverage. We have used the bathymetry grid along with the improved gravity to construct a global map of abyssal hill amplitude and orientations and compare the orientations with predictions from seafloor age gradient analysis. Areas of disagreement reveal propagating rifts, microplates, and tectonic reorganizations. This SRTM15_PLUS provides the foundational bathymetry layer for Google Earth and is freely available at our ftp site (topex.ucsd.edu).
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