The bathymetry of the ocean floors varies, just like land. The eastern United States coast is shallower than the west coast of the United States. The deepest trenches are found in the Marianas Trench in the south Pacific, which is the lowest point on the Earth’s surface. The Hawaiian Islands are just the tops of very high mountains. Seamounts are basically mountains that rise from the ocean floor but never surface. There are vast areas on the bottom of the oceans with no light and strange animals on an abyssal plain. There are also areas on the bottom where water of different densities can flow and erode just like rivers on the surface of the Earth.