HR: 0800h
AN: PP11A-0229    [Abstracts]
TI: Multiple Export Production and Sulfur Isotope Records over the Paleocene Eocene Thermal Maximum
AU: * Gray, E
EM: etgray@stanfordalumni.org
AF: Stanford University, Braun Hall (Geo Corner) #118 450 Serra Mall, Building 320, Stanford, CA 94305,
AU: Paytan, A
EM: apaytan@ucsc.edu
AF: Stanford University, Braun Hall (Geo Corner) #118 450 Serra Mall, Building 320, Stanford, CA 94305,
AB: The Paleocene Eocene Thermal Maximum (PETM) was a global climatic event that occurred 55 million years ago. δ¹⁸O values from benthic foraminifera indicate that temperatures rose 4-5^oC coeval with a precipitous drop in δ¹³C values that indicate a new source of carbon rapidly entered the global carbon cycle. Marine barite (BaSO₄) was used to evaluate the 1) barite accumulation rate that serves a proxy for export production and 2) the sulfur isotopic composition of seawater that reflects the mass balance of oceanic sulfate (SO₄^2-). Increased barite accumulation rates at the PETM suggest that increased export production and CO₂ sequestration was in direct response to the carbon isotope excursion, although not all of the increases are accounted for. High resolution δ³⁴S values are lower but within reasonable range of previously observed values and indicate a decrease in sulfate removal by pyrite deposition.
DE: 4901 Abrupt/rapid climate change (1605)
DE: 4924 Geochemical tracers
DE: 4940 Isotopic stage
DE: 4948 Paleocene/Eocene thermal maximum
SC: Paleoceanography and Paleoclimatology [PP]
MN: 2007 Fall Meeting