HR: 0800h
AN: PP11B-1448    [Abstracts]
TI: The Mg/Ca-Temperature Relationship in Benthic Foraminifera: Refining the Calibrations
AU: * Healey, S L
EM: shealey@geol.sc.edu
AF: Department of Geological Sciences, University of South Carolina, 701 Sunter St., Columbia, SC 29208 United States
AU: Thunell, R C
EM: thunell@geol.sc.edu
AF: Department of Geological Sciences, University of South Carolina, 701 Sunter St., Columbia, SC 29208 United States
AB: Core-top samples from the Vema Channel (southwestern Atlantic Ocean) and South China Sea were analyzed to further calibrate the sensitivity of benthic foraminiferal calcite magnesium/calcium (Mg/Ca) ratios to bottom water temperatures. Our sample set spans a depth range of 1400-4500 meters, and a temperature range of 0-4.3°C. We measured the Mg/Ca ratio of Cibicidoides wuellerstorfi, C. kullenbergi and Oridorsalis umbonatus using an inductively coupled plasma atomic emission spectrometer. Preliminary data indicate similar exponential relationships for C. wuellerstorfi and O. umbonatus to published calibrations (Martin et al., 2002; Lear et al., 2002). C. kullenbergi shows a greater sensitivity to temperature than C. wuellerstorfi. In all three cases a linear relationship describes the data as well if not better than an exponential curve, particularly at the low end of the temperature range (<4°C).
DE: 0419 Biomineralization
DE: 1065 Major and trace element geochemistry
DE: 4900 PALEOCEANOGRAPHY (0473, 3344)
DE: 4924 Geochemical tracers
SC: Paleoceanography and Paleoclimatology [PP]
MN: Fall Meeting 2005