The Floors of the Ocean: 1. The North Atlantic / Text to accompany the physiographic diagram of the North Atlantic

by Bruce C. Heezen; W. Maurice Ewing; Marie Tharp

DEFINITION

The third basic subdivision of the oceanic depression is the Mid-Oceanic Ridge, a continuous median ridge which runs the length of the North Atlantic, South Atlantic, Indian and South Pacific oceans, for more than 40,000 miles (Heezen and Ewing, in press). In the center third of the physiographic diagram a short segment of this world-encircling ridge is represented.