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This paper develops a technique that utilizes spatial and compositional trends in granite erratics distributed across the eastern and northwestern Queen Elizabeth Islands to discriminate between glacial dispersal trains originating from the Precambrian Shield of Ellesmere Island and the Canadian mainland. The distribution of glacially transported granite erratics in the eastern and northwestern Queen Elizabeth Islands defines a coherent pattern of regional dispersal from the Precambrian Shield of eastern Ellesmere Island. Principal components and cluster analyses demonstrate that most erratics within this dispersal train cluster within the same compositional group. Other members of this group represent outcrops on eastern Ellesmere Island, which define the locations of possible source areas. However, other compositional groups, which are unique to outcrops on the mainland, are absent from this dispersal train. Collectively, these spatial and compositional trends suggest that granite erratics on southwest Ellesmere, Amund Ringnes, and Meighen islands occur within a single dispersal train that resulted from the westward expansion of the Innuitian Ice Sheet from the Precambrian Shield of eastern Ellesmere Island. This technique may determine what differences, if any, exist among the composition of granite erratics deposited by the westward expansion of the Innuitian Ice Sheet across the Queen Elizabeth Islands and those deposited by the northward expansion of the Laurentide Ice Sheet. Any such differences may be useful in determining whether granite erratics of presently unknown provenance elsewhere in the Queen Elizabeth Islands are of Laurentide or Innuitian origin. [ABSTRACT FROM AUTHOR]

This paper presents relative sea-level curves from Amund and Ellef Ringnes islands, northwest Queen Elizabeth Islands. These curves are of exponential form and record continuous, ongoing Holocene emergence, although northwest Ellef Ringnes Island is experiencing a late Holocene transgression. Isobases drawn on postglacial shorelines rise southeastward towards an uplift centre in Norwegian Bay. These suggest the Ringnes Islands occupied the northwest radius of the Innuitian uplift, which is congruent with glacial geological evidence suggesting parts of the Ringnes Islands were covered by the Late Wisconsinan Innuitian Ice Sheet. The isobases provide a provisional reconstruction of glacioisostatic recovery within the northwest Innuitian uplift. Their pattern supports earlier reconstructions that maximum Late Wisconsinan ice thickness occurred across Norwegian Bay, marking the position of an ice divide, which is consistent with ice-flow features on Amund Ringnes Island. They record the diminishing thickness of the Innuitian Ice Sheet from Norwegian Bay to the Arctic Ocean. The absence of an isobase embayment across the Ringnes Islands suggests a relatively uniform ice load across both islands and Hassel and Massey sounds. Parallel isobases across Peary Channel indicate this ice load extended beyond Massey Sound, although their northward deflection suggests an increasing influence of the former Axel Heiberg Island ice load. [ABSTRACT FROM AUTHOR]