LATE QUATERNARY OSTRACODE ASSEMBLAGES FROM THE ARCTIC OCEAN

The paleoclimate and paleoceanographic conditions of the Arctic Ocean can be reconstructed using ostracode assemblages from radiocarbon dated sediment cores. In this study, we attempt to examine temporal patterns in ostracode assemblages during the last 40 ka in several regions of the Arctic, including the Mendeleev Ridge, Lomonosov Ridge, Gakkel Ridge, Morris Jesup Rise, and Yermak Plateau. New results from cores PS-2184 and PS-2186 from the Lomonosov Ridge were compared to previously published ostracode records. A total of 146,274 ostracode specimens were identified from 25 sediment cores. From a total of 27 species, the seven most abundant taxa are Acetabulastoma arcticum, Cytheropteron spp., Henryhowella asperrima, Krithe glacialis, Krithe minima, Pedicythere neofluitans, Polycope spp., and Pseudocythere caudata. Twelve faunal events were identified from changes in the relative frequency of these key taxa. We will discuss the timing of these events in relation to large-scale oceanographic changes during Marine Isotope Stage 3, the Last Glacial Maximum, the deglacial and the Holocene interglacial. In addition, a Detrended Correspondence Analysis (DCA) was used to compare different depth assemblages from every core.