sediment

1. N-VAR Sediment is solid material that settles at the bottom of a liquid, especially earth and pieces of rock that have been carried along and then left somewhere by water, ice, or wind. 沉淀物; 沉渣

Many organisms that die in the sea are soon buried by sediment. 许多在海里死亡的生物很快便被沉淀物掩埋。