* Biogenic: Formed from the remains of marine organisms, like shells, bones, and plankton.
* Terrigenous: Derived from erosion of continents and transported by rivers and wind.
* Volcanic: Material ejected from underwater volcanoes.
* Cosmogenic: Dust and debris from space.
The thickness of these sediments can vary greatly depending on the location and age of the ocean floor. Older parts of the ocean floor have thicker sediment layers than younger areas.
It's important to note that the sediments on top of the oceanic crust don't actually *form* the crust itself. They are just layers deposited on top of it.
