HR: 1340h
AN: PP23B-1408    [Abstracts]
TI: Pleistocene North Atlantic Deep Water Production; A Southern Hemisphere Perspective
AU: * Foote, J R
EM: jfoote1@student.gsu.edu
AF: Georgia State University, 24 Peachtree Center Ave., Atlanta, GA 30303 United States
AU: Christensen, B A
EM: bchristensen@gsu.edu
AF: Georgia State University, 24 Peachtree Center Ave., Atlanta, GA 30303 United States
AU: Shackford, J K
EM: jshackford1@student.gsu.edu
AF: Georgia State University, 24 Peachtree Center Ave., Atlanta, GA 30303 United States
AB: Faunal counts and stable isotopes of planktonic foraminifera are used to identify glacial-interglacial and millennial scale change in Pleistocene Atlantic interhemispheric transport. The sampling site, ODP Site 1085, has a sedimentation rate of approximately 5 cm/k.y. Samples were taken every 2 cm throughout the sections of the core representing the last 200 k.y., giving the site a resolution of approximately 500 years, high enough to observe glacial-interglacial variation, Dansgaard/Oeschger temperature cycles, and Heinrich events, within the Nyquist frequency. {\it Globigerina bulloides}, found in cold, nutrient-rich water, is used as a proxy for upwelling (Girardeau 1992). At Site 1085, {\it G. bulloides} peaks both during glacial and interglacial periods. The interglacial peaks covary with peaks of terrigenous sediment greater than 10 microns, an indicator of aeolian transport (Stuut et al. 2002), indicating a link between upwelling and wind strength at that time. The glacial peaks broadly correlate to a low C/N ratio, indicating a probable marine cause for the upwelling, such as an enhanced Benguela Current. Additionally, there is higher-frequency (sub-Milankovitch) variability through both the glacial and interglacial periods.
DE: 3344 Paleoclimatology
DE: 4267 Paleoceanography
DE: 3030 Micropaleontology
SC: Paleoceanography and Paleoclimatology [PP]
MN: 2004 AGU Fall Meeting