Late Quaternary in North America

Abstract

The Late Quaternary Glaciations in North America are reasonably well documented for marine isotope stages 2 into 1, but the spatial and temporal histories of the various ice sheets and mountain glacier complexes are still poorly constrained for the period 30-115. cal. ka BP. Significant evidence for ice sheet activity is now becoming increasingly noted from studies of marine cores that record evidence of major ice sheet instabilities, especially during the North Atlantic Heinrich events that were sourced from Hudson Bay and Hudson Strait; although there is evidence that other major ice streams along the Labrador Sea and Baffin Bay margins had similar if not coveal responses. The large number of radiocarbon dates that record deglaciation has allowed the construction of continental-scale maps that portay the retreat of the Laurentide, Cordilleran, and Innuitian ice sheets. Most notable is the asymmetric retreat of the Laurentide Ice Sheet to the uplands of the Eastern Canadian Arctic.