Deposition on Ocean Floor
Sedimentary Rock Processes
Rivers contribute a lot of sediment to the Earth's oceans through deltas. Much of the larger sediment requires more energy to move and usually doesn't travel as far; however, small sediment (silt- and clay-sized particles) can travel through the ocean and be deposited in the abyssal plain. Although rivers can carry a great amount of sediment, the majority of sediment within the oceans is derived from the marine organisms themselves. Many marine organisms have hard parts that are largely composed of calcium carbonate. As this material is shed or the organism dies, it settles to the ocean floor. Through time this sediment can buildup can compact to form limestone rocks. Skeletal fragments that buildup along the continental shelf and shallower environments can also be transported and distributed throughout the deeper regions of the ocean.