Deep sea sediments are usually found at sea depths that are greater than five hundred meters. They occupy about two thirds of the earth and they are of many kinds. Charnock et al (1990) grouped sea sediments into various categories such as terrigenous, authigenic, biogenic, pelagic, and hydrogenous. Others may be wind borne, volcanic or extra terrestrial. Biogenic sediments are those that come from biological matter. Volcanogenic sediments come from volcano ash. Terrigenous sediments come from material on the sea that is eroded. Terrigenous sediments constitute of glacial marines, brown clays, turbidites, debris flow, slide and slump. Pelagic sediments constitute of brown clays, biogenic carbonate oozes, globigerina, pteropod, coccolithopore, diatom and radiolarian.
Carbonate oozes is one of the dominant sediment and covers most of the ocean floor. Authigenic sediments comprise of manganese nodules, zeolites, extra terrestrial and phosphate nodules. Biogenic sediments are controlled by various elements of the surface water of the ocean. These elements are supply of nutrients, warmth, salt amounts, oxygen, carbon dioxide and the pH. Authigenic sediments usually vary with the location and amount of black smoke activity on the ridges. They are also controlled by location of up swelling zones and extremely slow processes that generate sediments if all the other types are not present. Terrigenous sediments are controlled by how close the land is to glaciers, rives, mountains, volcanoes and deserts.
The presence of sea sediments is determined by production of pelagic organisms, land erosion, volcanoes eruptions and cosmic fallout. Sea sediments may be dispersed to the sea by winds and gravity flows. They may also be distributed by surface currents or melting ice. Sediments may also come from biota from the overlying ocean water, chemical precipitates from the sea water and eroded material that is taken to the sea by rivers that drain into the ocean. Small amounts of sediments also come from interstellar dus