Geomorphic evidence for late glacial ice dynamics on southern Baffin Island and in outer Hudson Strait, Nunavut, Canada

Abstract

We here describe glacial geomorphology that sheds light on ice-dynamic conditions during the Noble Inlet advance, a glacial event involving northward ice flow across Hudson Strait and large-magnitude meltwater drainage across Meta Incognita Peninsula at around 8.9 to 8.4 14C kyr BP. Through airphoto interpretation and field inspection of key sites we mapped the glacial geomorphology of interior Meta Incognita Peninsula, the postulated terminal zone for northward expansion of ice from Quebec-Labrador during the Noble Inlet advance. A 170-km-long zone of glaciofluvial canyons, washing zones and boulder deltas was traced from Shaftesbury Inlet to Henderson Inlet. This zone reflects initial drainage across Meta Incognita Peninsula at >520 m elevation, followed by ice marginal drainage at progressively lower levels along the southern slope of the peninsula. The ice marginal outline required to explain the glaciofluvial zone is compatible with northward-trending striae previously reported from the southern coast of Meta Incognita Peninsula. A very large flux of meltwater across Meta Incognita Peninsula probably occurred because eastward supraglacial drainage on ice in Hudson Strait was temporarily impeded and steered northward by a raised ice surface level in outer Hudson Strait, induced by an enhanced outflow of ice from Ungava Bay.