Quaternary Calcareous Nannofossils from Periantarctic Basins: Paleoecological and Paleoclimatic Implications

Currently, coccolithophores have a widespread oceanic distribution and are reported from most latitudes, but not those higher than 658S. Fifteen piston cores were sampled with the aim of investigating the distribution and abundance variation of Quaternary calcareous nannofossils of the Antarctic region, south of the Antarctic Divergence (N658S), particularly from Maud Rise, Bausan Bank, and from Weddell, Ross and Bellingshausen Seas. A calcareous nannofossil cold-taxa association is present in most of the cores examined and their discontinuous occurrence is thought to indicate key environmental relationships. The presence of calcareous nannofossils is correlated with interglacial intervals with warmer SSTs and may indicate high productivity and an open-ocean environment. Our results confirm that, during short periods of the late Quaternary, coccolithophorids occurred at southern high latitudes, in the western Antarctic basins, while in the eastern Antarctic basins they are nearly absent, suggesting more variable SSTs near West Antarctic Ice Sheet.