The last glaciation of west-central Ellesmere Island, Arctic Archipelago, Canada
Locally abundant ice-marginal landforms lie in a 500 km long zone with a distal margin 10–60 km west of the margins of modern ice caps on central Ellesmere Island. Much of this drift belt, at the heads of the fiords, was deposited by the oscillating margin of a coalesced predecessor of the modern ic...
Published in: | Canadian Journal of Earth Sciences |
---|---|
Main Author: | |
Format: | Article in Journal/Newspaper |
Language: | French |
Published: |
Canadian Science Publishing
1985
|
Subjects: | |
Online Access: | http://dx.doi.org/10.1139/e85-035 http://www.nrcresearchpress.com/doi/pdf/10.1139/e85-035 |
Summary: | Locally abundant ice-marginal landforms lie in a 500 km long zone with a distal margin 10–60 km west of the margins of modern ice caps on central Ellesmere Island. Much of this drift belt, at the heads of the fiords, was deposited by the oscillating margin of a coalesced predecessor of the modern ice caps between 9000 and 7000 BP. The ice continued to retreat east of the present margin, and readvanced to its modern limit in a middle and late Holocene cooler climate. Unweathered but undated till and striations at the base of the drift suggest that the belt does not mark the western limit of central Ellesmere Island ice in the last glaciation. The limit lies an unknown distance downfiord; glaciers in the fiords may have floated. No reliable evidence was found for a complete ice cover of western Ellesmere Island and Eureka Sound in the last glaciation; nevertheless much of central and southern Ellesmere Island and Devon Island may have been glaciated by a regime that left few erosional or depositional landforms. Alternatively, emergence of an unglaciated Eureka Sound, underway by 9000 BP, may have followed combined peripheral glacioisostatic depression by encircling ice caps, whereas at the drift belt emergence was less and later, controlled only by central Ellesmere Island ice. |
---|