Deep-Sea Deposits

Deep-Sea Deposits

 

oceanic and marine sediments deposited on the continental slope between the neritic and abyssal zones at depths from 200 to 2,500 m. They occupy 19.4 percent of the area of the world’s oceans. Terrigenous sediments resulting from the erosion of detrital material and clay particles from dry land account for 56.5 percent of deep-sea bathyal deposits; second in importance is limestone silt (29.5 percent), in which foraminiferous, coral, and crustacean varieties are about equally distributed; next comes silicon silt, occupying about 8 percent of the area of the continental slope, and represented by diatomic and (much more rarely) radiolarian varieties. Vulcanogenic sediments (5 percent) are confined to regions of modern volcanic activity. Analogues of deep-sea deposits are known among the sedimentary layers of the Lower Cretaceous and Flysch eras.

A. B. RONOV

References in periodicals archive ?
Deep-sea deposits can be rich sources of precious metals, rare earths, and other valuable minerals.
Still, some scientists have called the accusations swirling around the Campos basin hasty and exaggerated, in light of the small, naturally occurring seeps that originally attracted oil companies to the deep-sea deposits.
If Japan develops the deep-sea deposits, which government sources say could come into production within five to 10 years, it would be a major coup.
Scientists increasingly believe that these deep-sea deposits constitute the world's remaining sources of oil.
Isolated, but highly concentrated, deep-sea deposits of manganese, gold, nickel, and copper, first discovered in the late 1970s, continue to tempt investors.