Contributed by Stephanie Healey, Cayce Lillesve, Kate Visser while students of USC taking the course Marine Sediments 553
Connection between carbonate slopes and the continental slope?
The continental slope begins seaward of the shelf break and as a part of the continental margin is underlain by continental crust. This surface extends to between 2 and 3 km water depth and is incised by numerous submarine canyons. These serve as chutes along which sediments are transported from the continental margin to the deep ocean.
The continental slope is covered by sediments and here we focus those that are calcareous. Commonly the carbonate slope lies above the lower limit of oxygenated water and so is able to support aerobic life forms. carbonate slopes can range in morphology from gentle gradients to steep cliffs. These differences in gradient are influenced by the sediment budget.
What makes up a carbonate slope deposit?
Sediments formed by carbonate either from the direct precipitation of aragonite and calcite from seawater or from the activities of organisms (such as corals, mollusks) which construct their shells out of aragonite or calcite. When the organisms die, their skeletal material falls to the sea floor. These particles can be either sand- or mud-sized, and hence carbonate deposits are classified as either carbonate sands or carbonate muds.
There are several factors that control the morphology of a carbonate slope as well as the type of sediments found there... Click on the links in the picture below to find out more.
Factors controlling carbonate slope facies:
Leeward Margin of the Tongue of the Ocean, Bahamas (Grammer et al., 1993)