Late Wisconsinan glaciation of the central sector of the Canadian High Arctic

Geomorphic and chronological evidence from Cornwall Island in the Canadian High Arctic Archipelago provides direct evidence for the age and dynamics o f the center and northern flank of the Innuitian Ice Sheet that covered the islands during the Late Wisconsonian glacial maximum. Dispersal of erratic s and glacial landforms indicate that ice flowed north across the island an d converged with ice flowing northwest from Norwegian Bay. Cornwall Island was initially deglaciated at 9000 C-14 yr B.P. in near synchrony with widel y separated sites in adjacent parts of the archipelago. This regional chron ology suggests rapid breakup of a marine-based Innuitian Ice Sheet that was destabilized by rapid eustatic sea-level rise and ice thinning during the early Holocene. This evidence provides strong support for a recently propos ed ice divide spanning the central part of the Canadian High Arctic and ind icates that most, if not all, of the region was glaciated during the Late W isconsinan. (C) 2000 University of Washington.