SS3.09 Climate-Lake Interactions
Date: Wednesday, June 12, 2002
Time: 12:00:00 PM
Location: Colwood
 
TaylorBE, Savannah River Ecology Laboratory, Aiken, USA, taylor@srel.edu
Brooks, M, J, Savannah River Archaeological Research Program, New Ellenton, USA, mjbrooks@sc.edu
Gaiser, E, E, Southeast Environmental Research Center, Miami, USA, gaisere@fiu.edu
 
RECONSTRUCTING HYDROLOGIC CONDITIONS SINCE THE MID-HOLOCENE ON THE UPPER ATLANTIC COASTAL PLAIN IN SOUTH CAROLINA
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Paleoenvironmental records from two isolated wetland ponds on the Savannah River Site in the Upper Coastal Plain of South Carolina indicate moist hydrologic conditions since the mid- Holocene, interrupted by at least one prolonged drier episode. The modern regime was not established until late prehistoric or early historic times. Radiocarbon dates from basal organic sediments of Flamingo Bay indicate that the deepest part of the basin has been paludified since around 4,500 radiocarbon yr B.P. Since 3,100 radiocarbon yr B.P., the paludified zone has extended to an elevation about 50 cm above the original elevation; since 300-230 radiocarbon yr B.P., about 1 m above the original elevation. The uppermost surface is now inundated about 80% of the year (1988-1994). Sediment changes and diatom assemblages at Peat Bay indicate an open water pond at 4600-3800 radiocarbon yr B.P. and corroborate the inference of moist hydrologic conditions. Diatom assemblages from the wetland pond that developed subsequently suggest a drier episode about 1300-1600 radiocarbon yr B.P. Progressively moister conditions occurred after 500 yr B.P.