sediment marine sediment ENVO ENVO:00002113 EcoLexicon:marine_sediment EcoLexicon:marine_sedimentation Marine sediment is a sediment that accumulates in the flat or very gently sloping areas of the deep ocean basin floor. The three main types of marine sediment, also known as pelagic sediment, are siliceous oozes, calcareous oozes, and red clays. SWEETRealm:MarineSediment Wikipedia:Marine_sediment pelagic sediment {alternative name}