Monday, 27 August 2007
1.PS-4
Evidence for a long warm interglacial during Marine Isotope Stage 31: Comparison of two studies at proximal and distal ODP sites in the Southern Ocean
Lora Teitler1, Gary Kupp1, Detlef Warnke1, and Lloyd Burckle2. (1) Department of Geological Sciences, California State University, East Bay, 25800 Carlos Bee Blvd., Hayward, CA 94542, (2) Lamont Doherty Earth Observatory, Columbia University, Palisades, NY
Summary We report here on studies of ice-rafted debris (IRD) from Marine Isotope Stages (MIS) 34-30 at distal Ocean Drilling Program (ODP) Site 177-1090 (subantarctic South Atlantic) and proximal ODP Site 188-1165 (Prydz Bay, Antarctica). The presence of the base of the Jaramillo Subchron (straddling MIS 31) facilitates correlation between sites. At the distal site, only very little IRD is present during MIS 31-33, with a small increase during MIS 32. At the proximal site in Prydz Bay , of these three stages, only MIS 31 can be identified. Here, during MIS 31, IRD is low, while foraminiferal percentages are high. This record is similar to that from Cape Roberts Project (CRP) drill site CRP-1 (Scherer et al., 2002). Therefore, MIS 31, and perhaps all of MIS 33-31, was a long, warm interval, and may have compromised the stability of the West Antarctic Ice Sheet.