Preservation of organic matter in marine sediments: controls, mechanisms, and an imbalance in sediment organic carbon budgets?

The burial of organic matter (OM) in marine sediments represents the major link between “active” surface pools of carbon in the oceans, atmosphere, on land, and in marine sediment, and carbon pools that cycle on much longer, geologic time scales (i.e., carbon in sedimentary rock, coal, and petroleum deposits). It also plays some role in controlling atmospheric CO2 and O2 on these long time scales because in a highly simplified fashion OM burial in sediments can be thought of in terms of the balance between primary production and respiration on land and in the oceans.