Monday, 27 August 2007
1.PS-18
Integrated provenance characteristics of glacial-marine sediment from the East Antarctic Margin
S. Brachfeld1, S.R. Hemming2, T. Van de Flierdt2, S. L. Goldstein2, M. Roy3, T. Williams2, and M. Rosig1. (1) Department of Earth and Environmental Studies, Montclair State University, Montclair, NJ 07043, (2) Lamont-Doherty Earth Observatory, Columbia University, Palisades, NY 10964, (3) Départment des Sciences de la Terre, Université du Québec à Montréal, C.P. 8888, Succ. Centre-Ville, Montréal, QC QC H3C 3P8, Canada
A combination of provenance tracers has been applied to nearshore glacial-marine diamict samples from the East Antarctic margin. The George V Coast has several distinctive characteristics, including abundant metamorphic lithic clasts, old 40Ar/39Ar ages and high concentrations of Mn and Cr relative to Prydz Bay and Mac.Robertson Land. Mac.Robertson Land also displays high metamorphic content and high garnet content relative to Ross Sea tills (Licht et al., 2005). The East Antarctic margin samples have strongly negative eNd values and old 40Ar/39Ar ages relative to West Antarctica. These characteristics may provide a means of identifying ice rafted debris and fine-grained sediment that was supplied to the Southern Ocean by the East Antarctic Ice Sheet. A more comprehensive survey is in progress in order to discern in detail the regional contributions from different flow lines within Antarctica’s ice sheets.