Today, seafloor mapping is essentially a form of remote sensing that uses similar concepts and applications to satellite-based systems, albeit adapted to the complex environment of the oceans.
ocean mapping
GIS Data
Jason-2 Satellite to Help Improve Maps of Sea Floor
Jason-2 will be collecting data about the sea floor every 5 miles, which will be used to create a high-definition estimate of the average surface height of the ocean in various places around the globe.