HR: 1340h
AN: OS33A-0579    [Abstracts]
TI: Tropical Sea Surface Temperature Variability During Marine Isotope Stage 3: Mg/Ca results from the Cariaco Basin, Venezuela
AU: * McConnell, M C
EM: mmcconnell@geol.sc.edu
AF: Department of Geological Sciences, University of South Carolina , Columbia, SC 29208
AU: Thunell, R C
EM: thunell@geol.sc.edu
AF: Department of Geological Sciences, University of South Carolina , Columbia, SC 29208
AU: Peterson, L C
EM: lpeterson@rsmas.miami.edu
AF: Rosenstiel School of Marine & Atmospheric Science, University of Miami , Miami, FL 33149
AU: Black, D
EM: dblack1@uakron.edu
AF: Department of Geology, University of Akron, Akron, OH 44325
AB: Magnesium/calcium \{Mg/Ca\} ratios were measured in the surface dwelling planktonic foraminiferal species \(Globigerinoides ruber\) \{white variety\} from a high deposition rate sediment core collected in the Cariaco Basin, located on the northern continental shelf of Venezuela, in order to assess the magnitude of sea surface temperature \{SST\} changes associated with stadial/interstadial oscillations during Marine Isotope Stage 3. Specifically, we have generated a high resolution SST record for interstadials 5-8 \{$\sim$35 to 45 ka\}. The Mg/Ca ratios of \(G. ruber\) \{white\} document large surface temperature oscillations that appear to co-vary with the Greenland ice-core air temperature records. The lowest values were obtained from the end of interstadial 6 \{$\sim3$mmol/mol\} and the highest values were obtained during interstadial 7 \{$\sim5$mmol/mol\}. This represents a temperature change of $\sim$$5.5\deg$C. We have also measured the Mg/Ca ratio in two other species of planktonic foraminifera, \(G. ruber\) \{pink variety\} and \(Globigerina bulloides\). The trace metal data is compared with foraminiferal oxygen isotope measurements made on the same suite of samples to assess the internal consistency of these temperature proxies.
DE: 4875 Trace elements
DE: 4215 Climate and interannual variability (3309)
DE: 4267 Paleoceanography
DE: 4802 Anoxic environments
SC: Ocean Sciences [OS]
MN: 2004 AGU Fall Meeting