HR: 0830h
AN: PP31B-0253    [PDF]
TI: {\it Eucampia antarctica} Abundance Stratigraphy in the Southern Ocean
AU: * de Give, D
EM: degived@rice.edu
AF: Lamont-Doherty Earth Observatory, P.O. Box 1000, Palisades, NY 10964 United States
AU: * de Give, D
EM: degived@rice.edu
AF: Rice University - Lovett College, 6310 Main Street, Houston, TX 77005 United States
AU: Anderson, K
EM: kristin.anderson@yale.edu
AF: Lamont-Doherty Earth Observatory, P.O. Box 1000, Palisades, NY 10964 United States
AU: Anderson, K
EM: kristin.anderson@yale.edu
AF: Yale University, P.O. Box 200153, New Haven, CT 06520 United States
AU: Hew, C
EM: christih@andrew.cmu.edu
AF: Lamont-Doherty Earth Observatory, P.O. Box 1000, Palisades, NY 10964 United States
AU: Hew, C
EM: christih@andrew.cmu.edu
AF: Carnegie Mellon University - SMC 3296, 5032 Forbes Avenue, Pittsburgh, PA 15213 United States
AU: Anderson, B E
EM: Brenton.Anderson@sunysb.edu
AF: Lamont-Doherty Earth Observatory, P.O. Box 1000, Palisades, NY 10964 United States
AU: Anderson, B E
EM: Brenton.Anderson@sunysb.edu
AF: State University of New York, North Loop Rd., Stony Brook, NY 11790 United States
AU: Burckle, L H
EM: burckle@ldeo.columbia.edu
AF: Lamont-Doherty Earth Observatory, P.O. Box 1000, Palisades, NY 10964 United States
AU: Anderson, R F
EM: boba@ldeo.columbia.edu
AF: Lamont-Doherty Earth Observatory, P.O. Box 1000, Palisades, NY 10964 United States
AB: {\it Eucampia Antarctica} (diatom) relative abundance stratigraphy is a useful biostratigraphic tool for identifying and correlating late Quaternary glacial/interglacial sequences in Southern Ocean sediments, especially for those regions where $^{14}$C dating and $\delta^{18}$O stratigraphy are not available. Understanding the nature of the variability of {\it E. Antarctica} abundances greatly improves its reliability as a biostratigraphic tool. Hence, a spatial analysis of {\it E. Antarctica} abundance and $^{230}$Th-normalized {\it E. Antarctica} flux is conducted using data from several Atlantic and Pacific sites. An {\it E. Antarctica} stratigraphy is presented for several cores in the Pacific sector and compared to magnetic susceptibility records. Last Glacial Maximum (LGM) depths are determined from this stratigraphy and shown to be well correlated across the Pacific sector. Variations are noted in percent {\it E. Antarctica} within each sector of the Southern Ocean at different latitudes and between the Atlantic and Pacific sectors where data available from existing studies are merged. Average values of absolute {\it E. Antarctica} flux during the Holocene and LGM, computed using $^{230}$Th-normalized opal fluxes and percent {\it E. Antarctica}, are compared at several sites in the Atlantic and Pacific sectors of the Southern Ocean. This analysis demonstrates a comparatively small variation in absolute numbers of {\it E. Antarctica} in the Pacific sector between the LGM and Holocene at all sites studied but a noticeable increase in the Atlantic sector just north of the Antarctic Polar Front (APF) during the LGM implying that it is not only the relative abundance of {\it E. Antarctica} that increases during glacial periods in certain regions but also its absolute abundance.
DE: 3022 Marine sediments--processes and transport
DE: 3030 Micropaleontology
DE: 3309 Climatology (1620)
DE: 4267 Paleoceanography
SC: Paleoceanography and Paleoclimatology [PP]
MN: 2003 Fall Meeting