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TitleHolocene delevelling of Devon Island, Arctic Canada: implications for ice sheet geometry and crustal response
AuthorDyke, A S
SourceCanadian Journal of Earth Sciences vol. 35, 8, 1998 p. 885-904, (Open Access)
Alt SeriesGeological Survey of Canada, Contribution Series 1997203
PublisherCanadian Science Publishing
Mediapaper; on-line; digital
File formatpdf
NTS38F/13NW; 38G/04NW; 38G/04SW; 38G/01SW; 38G/01NW; 48E/09; 48E/10; 48E/11; 48E/12; 48E/13; 48E/14; 48E/15; 48E/16; 48F/09; 48F/10; 48F/11; 48F/12; 48F/13; 48F/14; 48F/15; 48F/16; 48B/06NW; 48B/07NW; 48G; 58E/09; 58E/10; 58E/11; 58E/12; 58E/13; 58E/14; 58E/15; 58E/16; 58F/16NE; 58F/16SE; 58G/01NE; 58G/01SE; 58G/08NE; 58G/08SE; 58G/09NE; 58G/09SE; 58G/16NE; 58G/16SE; 58H; 59A; 59B; 59C/04SW; 59D/01; 69A/09; 69A/16
AreaDevon Island; Simmons Peninsula; North Kent Island
Lat/Long WENS -96.5000 -79.5000 77.1667 74.3333
Subjectssurficial geology/geomorphology; Holocene; ice sheets; ice morphology; radiocarbon dates; sea level changes; crustal uplift; ice thickness; glacial history; Innuitian Ice Sheet; Wisconsinan Ice Sheet; sea level history; Quaternary
Illustrationsprofiles; maps; graphs
AbstractThe raised beaches and deltas of Devon Island contain an abundance of dateable materials. A large set of radiocarbon dates (228), 154 of which are new, are used to construct relative sea level curves and isobase maps for the island. The best materials for this purpose are driftwood logs (61 dates) and bowhead whale bones (74 dates) from raised beaches and mollusc shells from marine-limit deltas (20 dates) or from altitudes close to marine limit (14 dates). During the last glacial maximum, the island is thought to have lain beneath the southeastern flank of the Innuitian Ice Sheet. The relative sea level history is congruent with that inferred ice configuration. The island spans half the ice sheet width. Relative sea level curves are of simple exponential form, except near the glacial limit where an early Holocene emergence proceeded to a middle Holocene lowstand below present sea level, which was followed by submergence attending the passage of the crustal forebulge. The response times of relative sea level curves and of crustal uplift decrease from the uplift centre toward the limit of loading, but the change appears strongest near the limit. The Innuitian uplift is separated from the Laurentide uplift to the south by a strong isobase embayment over Lancaster Sound. Hence, ice load irregularities with wavelengths of about 100 km were large enough to leave an isostatic thumbprint in this region of the continent. The apparent absence of a similar embayment over Jones Sound probably indicates a greater Late Wisconsinan ice load there, or a thicker crust than in Lancaster Sound.

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