Sludge and Sediment Cores

Sediment is any particulate matter that can be transported by fluid flow, and which eventually is deposited.
Sediments are most often transported by water (fluvial processes) transported by wind (aeolian processes) and glaciers. Beach sands and river channel deposits are examples of fluvial transport and deposition, though sediment also often settles out of slow-moving or standing water in lakes and oceans.