2015 GSA Annual Meeting in Baltimore, Maryland, USA (1-4 November 2015)

Paper No. 313-2
Presentation Time: 9:00 AM-6:30 PM

ORGANIC-RICH SEDIMENTS FROM A SOUTHERN APPALACHIAN WETLAND PROVIDE A RECORD OF LATE PLEISTOCENE THROUGH HOLOCENE ENVIRONMENTAL CONDITIONS


TANNER, Benjamin R., Geosciences & Natural Resources, Western Carolina University, Cullowhee, NC 28723 and KEEVER Jr., Michael, Geosciences & Natural Resources, Western Carolina University, 1 University Way, Cullowhee, NC 28723, btanner@wcu.edu

Sites that preserve a record of late Pleistocene through Holocene environmental change are rare in the Southern Appalachians. A wetland deposit near the campus of Western Carolina University, in Speedwell, NC, began organic sediment accumulation between 12,130 and 12,550 cal yr BP (127 cm below surface - all ages reported here represent calibrated, 2σ ranges). A radiocarbon age determination at 80 cm below surface yielded a result of 9,700 to 10,150 cal yr BP, and the 40 cm sample depth yielded an age of 2710 to 2775 cal yr BP. C/N decreases moving from the Pleistocene into the Holocene deposits at the site, and then remains fairly steady up core. δ13C values are highest in the mid-Holocene portion of the core, perhaps indicating more C4 plant input to the organic sediment pool, and possible warmer or drier conditions. These initial measurements at the Speedwell site agree well with the multi-proxy Holocene record preserved at the Panthertown site (recently published), which is located ~20 km from Speedwell. These two records will be compared and inferences made regarding local terminal Pleistocene through Holocene environmental conditions.