LIPID BIOMARKERS AND PALEOVEGETATION DETERMINATIONS FOR THE LAST 60,000 YEARS AT ELIKCHAN LAKE, NORTHEAST SIBERIA

Sedimentary cores from Elikchan Lake, northeast Siberia, provide a continuous sequence of deposition for at least the last 60,000 years (Lozhkin and Anderson, 1996). Pollen analysis indicates several shifts between forest and tundra dominated vegetation between 27,000 and 60,000 years ago (Lozhkin and Anderson, 1996). Lipid biomarker concentrations of modern plants, a plankton tow, and core sediments from Elikchan Lake have been investigated to better understand organic matter sources, deposition and diagenetic effects within the catchment. A tertiary plot of unsaturated C-26, C-28, and C-30 n-fatty acids indicate that modern plants have distinctive n-fatty acid compositions. The concentrations of these n-fatty acids shift downcore in response to changes in source material deposition and diagenetic effects. The lipid biomarker concentration data will eventually be coupled with d13C analysis and pollen data to evaluate carbon cycling within the basin and correlate it to climate change.