Integrated micropaleontological and stratigraphical study of the Late Quaternary Arcose C_33 core (offshore SW Sardinia)

We present the preliminary results of an ongoing multidisciplinary study which involves the sedimentary succession of the Arcose C_33 core, located on the Sentinelle Valley (Sardinia Channel, Western Tyrrhenian Sea), drilled at a water depth of 2368 m during the IAMC-CNR Arcose Cruise (September 2010). The succession, 6.58 m thick, mainly consists of homogeneous grey marly clays, with rare few centimeters thick sandy levels and represents one of the best Late Quaternary sedimentary record of the central Western Mediterranean. The core has been very closely-spaced sampled with the aim of obtaining high resolution chronostratigraphic, biostratigraphic, paloenvironmental and paleoclimatic data for the last 100 kyr. The analyses of the Calcium Carbonate content highlighted a marked lithological ciclicity, reflecting an orbital/suborbital control on the deposition of the succession itself. Quantitative analyses of planktonic foraminifers and calcareous nannofossils have been performed with the aim of identifying a set of eco-biozones, based on the relative abundance of climate-sensitive taxa. The stable isotope analyses (18O and 13C) will be performed with the double aim to provide an accurate age and paleoclimatic control. The present results have been successfully compared with available data obtained in coeval Mediterranean successions (e.g. Peres-Folgado et al., 2003, 2004; Budillon et al., 2009; Incarbona et al., 2009, 2010) thus indicating that the oscillations of the micropaleontological content are correlated with climatic global events and can thus be used for large-scale correlations. In particular, the peculiar variations of selected taxa suggest the presence of glacial/interglacial oscillations and higher frequency events such as the sub-Milankovian Dansgaard-Oeschger events.