NASAGodrd

Three fifths of the Earth's surface is under the ocean, and the ocean floor is as rich in detail as the land surface with which we are familiar. This animation simulates a drop in sea level that gradually reveals this detail. As the sea level drops, the continental shelves appear immediately. They are mostly visible by a depth of 140 meters, except for the Arctic and Antarctic regions, where the shelves are deeper. The mid-ocean ridges start to appear at a depth of 2000 to 3000 meters. By 6000 meters, most of the ocean is drained except for the deep ocean trenches, the deepest of which is the Marianas Trench at a depth of 10,911 meters.