Wednesday, 29 August 2007 - 10:50 AM
3.A.B-3
A Proposed Community Wide Analytical Network Using a New Approach to Radiocarbon Dating of Antarctic Glacial Marine Sediments
Brad Rosenheim1, Eugene W. Domack2, John Hayes, Mary Beth Day2, Heather Schrum3, and Mark Roberts4. (1) National Ocean Sciences Accelerator Mass Spectrometer, Woods Hole Oceanographic Institution, MS #8, Woods Hole Road, Woods Hole, MA 02543, (2) Department of Geosciences, Hamilton College, 198 College Hill Road, Clinton, NY 13323, (3) Graduate School of Geosciences, University of Rhode Island, South Ferry Road, Narragansett, RI 02882, (4) National Ocean Sciences Accelerator Mass Spectrometer facility, Woods Hole Oceanographic Institution, Woods Hole, MA 02543
Dependence upon bulk acid insoluble organic material (AIOM) for sediment chronology has led to long standing ambiguity in correlating sedimentary events across the Antarctic continental margin. We have developed a novel system that exploits the differences in thermal stabilities of organic compounds in AIOM to separate autochthonous carbon from the allochthonous, pre-aged carbon which leads to ambiguously old AIOM ages. Although complete separation of the AIOM components is difficult to achieve, our results offer a significant improvement to sedimentary chronology from the climatically important sedimentary sequences including those from: Antarctic Peninsula, NW Weddell Sea, and the Ross Sea. We outline a plan to establish a community wide submission process via two analytical labs linked to NOSAMS/WHOI enabling key marine sequences to be evaluated in a standard way to advance our understanding of Late Quaternary ice volume and relative sea level changes along the Antarctic margin.