Environmental Magnetic Record of Worldwide Late Pleistocene Climatic Events from the Pacific Margin of the Antarctic Peninsula

We report a high-resolution paleomagnetic and rock magnetic study carried out on three piston cores, recovered within the SEDANO Project in the western continental rise of the Antarctic Peninsula. The cores span the time interval between the present-day and the last interglacial, with one (SED-06) extending to about 150 kyr. An improved age model for the three cores was obtained by correlating the relative paleointensity records to global paleointensity reference curves (SINT-200). In such improved time frame we found that sharp coercivity minima (corresponding to characteristic dark grey layers in the last glacial interval of the SED-02 and SED-04 cores) are time correlated with the Heinrich events identified in the North Atlantic sediments. We relate such environmental magnetic signal to variations in deep sea diagenetic processes of sulphides formation, which reflect changes in the input of detrital organic matter controlled by past sea-ice extent. Because of the inherent chronological uncertainties it is not yet possible to identify time lags or leads in interhemispheric linkage, but the timing of these dark grey layers is close enough to that the Heinrich events to suggest an interhemispheric consistent response to global climate changes during the last glaciation.