| Title | Organic carbon deposition on the North Carolina continental slope off Cape Hatteras (USA) |
| Publication Type | Journal Article |
| Year of Publication | 2002 |
| Authors | Thomas, CJ, Blair, NE, Alperin, MJ, DeMaster, DJ, Jahnke, RA, Martens, CS, Mayer, L |
| Journal | Deep-Sea Research Part Ii-Topical Studies in Oceanography |
| Volume | 49 |
| Issue | 20 |
| Pagination | 4687-4709 |
| Date Published | 2002 |
| ISBN Number | 0967-0645 |
| Keywords | anaerobic methane oxidation, early diagenesis, margin, marine-sediments, MATTER, middle-atlantic-bight, sea-floor, shelf, south, waters |
| Abstract | The continental slope off Cape Hatteras, NC is a region of high sediment accumulation and organic matter deposition. Sediment accumulation rates range from 3 to 151 cm kyr(-1). Organic carbon deposition rates are 5-13 moles C m(-2) yr(-1), the highest reported for the slope off the eastern US. Burial efficiencies are 3-40%. The organic matter deposited is marine in origin and a mix of old and young particles. High organic carbon deposition rates support remineralization throughout the upper 2-3 m of sediment. Deep bioirrigation to depths of 60-100 cm within the seabed affects the biogeochemistry of the sediments by extending the zone of sulfate reduction and by steepening DIC porewater gradients through the non-local exchange of porewater. Stable and radiocarbon isotope mixing curves for porewater dissolved inorganic carbon (DIC) indicate that the dominant source of DIC accumulating in the upper 2-3 m of the seabed is of nearly uniform delta(13)C (-21.10parts per thousand) and Delta(14)C (-546parts per thousand.). (C) 2002 Elsevier Science Ltd. All rights reserved. |
