Late Wisconsin glaciation of Hadwen and Summer islands, Tuktoyaktuk Coastlands, NWT, Canada

The exact timing of the last major advance of the Laurentide Ice Sheet onto the Beaufort Sea coastlands of western Arctic Canada is unclear but significant to our understanding of landscape change and palaeo-ice stream chronology. Optical stimulated luminescence dating of preglacial and postglacial aeolian sand from Hadwen and Summer islands, in the Tuktoyaktuk Coastlands, indicates that glaciation took place between about 17.5 and 15 ka, and most likely between 16.6 and 15.9 ka, coinciding with Heinrich event 1. At this time the Mackenzie Trough palaeo-ice stream advanced into a cold-climate sandy desert, interrupting aeolian activity.