Processes controlling the organic carbon content of open ocean sediments

Use of sedimentary organic carbon concentrations as a record of paleoceanographic conditions is complicated by an insufficient understanding of the mechanisms controlling present‐day variations in the organic matter content of surface open ocean sediments. This paper is a review of organic carbon distributions in marine sediments, the global marine balance of particulate and dissolved organic carbon and the processes controlling organic matter diagenesis. The discussion focuses on the last topic with the intention of bringing together mass balance and organic chemical evidence for mechanisms that control the preservation of organic matter in open ocean sediments.