Southernmost evidence of large European Ice Sheet-derived freshwater discharges during the Heinrich Stadials of the Last Glacial Period (Galician Interior Basin, Northwest Iberian Continental Margin)

Abstract

The reconstruction of circum-Atlantic ice-sheets motions and instabilities is crucial to shedding light on the potential mechanisms that triggered and/or enhanced abrupt climate changes. Using environmagnetic and geochemical data, we provide a continuous and well-dated record of the evolution of the glacial/interglacial sedimentation on the NW Iberian Margin during the last glacial period, covering the last six Heinrich Stadials. Our results reveal the existence of European sediments related to meltwater pre-events at the initial stages of HS1, HS2, HS4 that corroborate the Channel river depositional history. They also show the presence of IRD from the Laurentide Ice Sheet, and from the European Ice Sheet at the final development stages of these stadials, i.e. Heinrich Events. Therefore, this study provides further insights into one of the potential forcing mechanisms for Heinrich Events, and by inference of Heinrich Stadials.