[2] The scouring of the land by the 3 km thick glaciers left numerous depressions, some of which contained stray chunks of ice that, upon melting during warmer periods, created kettle lakes and ponds.

The Precambrian granite bedrock of the Canadian Shield protrudes to the surface through other sedimentary deposits in areas that surround Hudson Bay.

Moreover, glacial erratic chunks of this rock may have been transported to other areas by the ice sheet, sometimes into surroundings with no common elements.

[2] Permafrost occurs in a continuous, permanent sheet throughout the zone,[3] which consists primarily of rollings plains west of the Shield area.

[2] Cyclic freezing and thawing of the soils results in irregular features throughout the terrain, including hummocks and polygonal shapes.