Melting of the late Pleistocene ice sheet has left a semicircle of glacial deposits around the coast of eastern Newfoundland west of the Avalon Peninsula. A discontinuous end moraine accentuates the curvature and separates ground moraine on the coastal side (outer drift zone) from slightly younger eskers, kames, and ground moraine on the inner side (inner drift zone). The distribution of ground moraine, glacial striations, indicator boulders, and glaciated bedrock ridges in the two drift zones indicates that an ice sheet once covered all eastern Newfoundland west of the Avalon Peninsula. The ice center was somewhere in western Newfoundland. At about the same time local ice caps existed on the Avalon Peninsula. Small valley glaciers persisted in a few elevated regions of the north and south coasts west of longitude 55° after the retreat of the main ice sheet.

Eastern Newfoundland appears to be tilting upward toward the northwest, with a zero isobase passing through Trinity and Placentia bays. Northwest of this axis the coast is emerging; southeast of it (on the Avalon Peninsula) the coast is submerging. The zero isobase veers west along the south shore of Newfoundland, parts of which are submerging, parts emerging.

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