Glacial Landform Assemblages of Mainland Nunavut, West of Hudson Bay and Their Palaeoglaciological Significance

Abstract

This case study focuses on the glacial landscapes of the low-relief tundra of the Canadian Shield of mainland Nunavut, west of Hudson Bay. Having been studied for well over a century, the glacial geomorphology of the region is spectacular and is widely recognised as being of international significance to palaeo-glaciology. At the global Last Glacial Maximum, the region lay close to the centre of the former Laurentide Ice Sheet and was submerged beneath a large (>3 km thick) ice dome, and with a major ice divide orientated roughly north-east to south-west (the Keewatin Ice Divide). This was an important influence on the distribution of glacial landforms and the aim of this chapter is to provide a concise overview of the key landform assemblages and their zonation around the Keewatin Ice Divide with a particular focus on hummocky terrain, ribbed moraines, drumlins, mega-scale glacial lineations, meltwater features, end moraines, and raised beaches and shorelines related to proglacial lakes and marine transgression. It is clear that whilst the distribution of landforms is a complex interplay between the overriding ice sheet properties (thickness, velocity, basal thermal regime) and the underlying geology, a detailed analysis of these landscapes has led to some important advances in our broader understanding of ice sheet dynamics and glacial geomorphology, particularly in the area of drift dispersal, the migration of ice divides, ice streaming and the evolution of subglacial meltwater drainage systems.