14C age corrections in Antarctic lake sediments inferred from geochemistry

Abstract

Sediment from Lake Boeckella, Antarctic Peninsula, is richer in Ca, Cd, Cu, P, Sr and Zn than that of six other lakes in the area. The elements originate from Adelie penguin (Pygoscelis adeliae) guano on the lake shores. Changing Cu and P concentrations in the lake sediment are used as proxy for penguin influence on the lake sediment from c5850 BP to present. The reservoir effect has been constant since at least 5800 BP, implying long-term stability of the currents and water masses in the area. The existing chronology for Lake Boeckella has been recalculated. The period of glacial advance, previously thought to have culminated at 5000 BP, is now thought to have culminated at 4700 BP; deglaciation of the area is thought to have occurred at 6300 BP instead of 8680 BP. -from Author