Joint 69th Annual Southeastern / 55th Annual Northeastern Section Meeting - 2020

Paper No. 65-2
Presentation Time: 1:30 PM-5:30 PM

SEDIMENT CORES FROM WHITE POND, SOUTH CAROLINA, CONTAIN A PLATINUM ANOMALY, PYROGENIC CARBON PEAK, AND COPROPHILOUS SPORE DECLINE AT 12.8 KA


MOORE, Christopher R.1, BROOKS, Mark J.2, GOODYEAR, Albert C.3, FERGUSON, Terry A.4, PERROTTI, Angelina G.5, MITRA, Siddhartha6, LISTECKI, Ashlyn M.6, KING, Bailey C.6, MALLINSON, David J.7, LANE, Chad S.8, KAPP, Josh D.9, WEST, Allen10, CARLSON, David L.11, WOLBACH, Wendy S.12, THEM II, Theodore R.13, HARRIS, M. Scott13 and PYNE-O'DONNELL, Sean14, (1)Savannah River Archaeological Research Program, South Carolina Institute of Archaeology and Anthropology, USC, PO Box 400, New Ellenton, SC 29809, (2)Savannah River Archaeological Research Program, South Carolina Institute of Archaeology and Anthropology, USC--Retired, 511 Migrant Camp Road, Batesburg, SC 29006, (3)South Carolina Institute of Archaeology and Anthropology, University of South Carolina, 1321 Pendleton Street, Columbia, SC 29208, (4)Environmental Studies, Wofford College, 429 N Church St, Spartanburg, SC 29303, (5)Geography Department, University of Wisconsin, 550 N Park Street, Madison, WI 53707-1404, (6)Geological Sciences (MS558), East Carolina University, Greenville, NC 27858, (7)Department of Geological Sciences, East Carolina University, 101 Graham Building, Greenville, NC 27858, (8)Department of Earth and Ocean Sciences, University of North Carolina Wilmington, 601 South College Rd., Wilmington, NC 28411, (9)Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, Santa Cruz, CA 95064, (10)Comet Research Group, Prescott, AZ 86301, (11)Department of Anthropology, Texas A&M University, College Station, TX 77843, (12)Department of Chemistry and Biochemistry, DePaul University, Chicago, IL 60614, (13)Department of Geology and Environmental Geosciences, College of Charleston, Charleston, SC 29424, (14)Earth Observatory of Singapore and Asian School of the Enviornment, NanyangTechnological University, Singapore, 000000, Singapore

A widespread platinum (Pt) anomaly was recently documented in Greenland ice and 11 North American sedimentary sequences at the onset of the Younger Dryas (YD) event (~12,800 cal yr BP), consistent with the YD Impact Hypothesis. We report high-resolution analyses of a 1-meter section of a lake core from White Pond, South Carolina, USA. After developing a Bayesian age-depth model that brackets the late Pleistocene through early Holocene, we analyzed and quantified the following: 1) Pt and palladium (Pd) abundance, 2) geochemistry of 58 elements, 3) coprophilous spores, 4) sedimentary organic matter (OC and sedaDNA), 5) stable isotopes of C (δ13C) and N (δ15N­), 6) soot, 7) aciniform carbon, 8) cryptotephra, 9) mercury (Hg), and 10) magnetic susceptibility. We identified large Pt and Pt/Pd anomalies within a 2-cm section dated to the YD onset (12,785 ± 58 cal yr BP). These anomalies precede a decline in coprophilous spores and correlate with an abrupt peak in soot and C/OC ratios, indicative of large-scale regional biomass burning. We also observed a relatively large excursion in δ15N values, indicating rapid climatic and environmental/hydrological changes at the YD onset. Our results are consistent with the YD Impact Hypothesis and impact-related environmental and ecological changes.