Does preservation of high organic matter concentrations in sediments requires anoxic bottom water?

Does preservation of high organic matter concentrations in sediments requires anoxic bottom water?


This is a matter of debate,
Calvert and Pederson (1992) point out that sediments accumulating in oxic and anoxic basins have similar organic carbon contents. They also argue that extent of decomposition of marine organic matter is similar under oxic and anoxic conditions.

On the other hand, Killops and Killops (1993) point out that ancient lipid-rich sediments of the sort likely to give rise to petroleum are generally finally laminated, implying a lack of bioturbation and, therefore, anoxic conditions at the sediment-water interface.