Ocean floor synonyms

The first ledge rising from the ocean floor has depth averaging 8000 ft.

been made to arrive at a definite international agreement on this subject, and certain terms suggested by a committee were adopted by the Eighth International Geographical Congress at New York in 1904.4 The forms of the ocean floor include the " shelf," or shallow sea margin, the " depression," a general term applied to all submarine hollows, and the " elevation."

The silica, in the form of diatom or radiolarian skeletons, is eventually deposited on the ocean floor after the death of the organisms. Most of the fine colloidal clay is, however, deposited as river-sludges when the fresh water carrying it mixes with denser sea-water.

The whole series was evidently deposited in shallow water on the summit of a submarine volcano standing in its present isolation, and round which the ocean floor has probably altered but a few hundred feet since the Eocene age.

Relief of the Ocean Floor.