Defining the maximum extent of the Laurentide Ice Sheet in Home Bay (eastern Arctic Canada) during the Last Glacial episode

Abstract

Three sediment cores recovered on the lower slope of the continental shelf in western Baffin Bay (Arctic Canada) as well as swath bathymetry and subbottom profiler data collected on the shelf and slope of the region were analysed to investigate whether the Laurentide Ice Sheet (LIS) reached the shelf edge offshore Home Bay during the Last Glacial Maximum (LGM). Physical, sedimentological and palaeomagnetic analyses of the cores were also used to constrain the chronostratigraphy of upper sedimentary facies of the Home Bay trough‐mouth fan (TMF). Seven lithofacies were identified in the cores and reveal that the sediments recorded a genuine geomagnetic signal and that the cores span the last 40 ka. In the Home Bay Trough, sets of elongated ridges are discernible on swath bathymetry imagery and are interpreted as mega‐scale glacial lineations (MSGLs) resulting from an ice stream eroding the trough and delivering glacigenic sediments to the TMF. The geomorphology of the TMF, combined with the sedimentary records and the chronostratigraphy, indicates that a series of debris flows and turbidity currents were generated between 35 and 15 ka BP. These results indicate that the LIS margin extended near the shelf edge during the LGM and allow us to propose a new maximum extent of the LIS during the Last Glacial episode.