C34A-05
Late Holocene Bottom Water Temperature Variations from the Herald Canyon, western Chukchi Sea
Wednesday, 16 December 2015: 17:15
3007 (Moscone West)
Natalia Barrientos1, Helen Coxall1, Caroline H Lear2, Martin Jakobsson1, Matthew O’Regan1, Christof Pearce1, Christian Stranne1, Francesco Muschitiello1 and Andrey Koshurnikov3, (1)Stockholm University, Department of Geological Sciences, Stockholm, Sweden, (2)Cardiff University, Cardiff, United Kingdom, (3)Moscow State University, Geophysics, Moscow, Russia
Abstract:
We present coupled stable isotope and trace metal records in benthic foraminifera to investigate the variability in past bottom water temperatures (BWT) from Core SWERUS-L2-2-PC1 (8.28 m) collected during the SWERUS-C3 Leg 2 Expedition in 2014. The core was retrieved at 71.7 m water depth from the Herald Trough, western Chukchi Sea. Radiocarbon dates revealed late Holocene linear sedimentation rates allowing the study of the core in high resolution. Preliminary Mg/Ca ratios in Nonionella labradorica and Elphidium excavatum clavatum with paired stable isotopes in Elphidium excavatum clavatum show a shift to either warmer or fresher bottom waters at around 2000-1800 years BP that suggests changes in the Pacific freshwater input via the Bering Strait.
