Title | Landscapes of cold-centred Late Wisconsinan ice caps, Arctic Canada |
| |
Author | Dyke, A S |
Source | Progress in Physical Geography vol. 17, no. 2, 1993 p. 223-247, https://doi.org/10.1177/030913339301700208 |
Image |  |
Year | 1993 |
Alt Series | Geological Survey of Canada, Contribution Series 36892 |
Publisher | SAGE Publications |
Document | serial |
Lang. | English |
Media | paper; on-line; digital |
File format | pdf |
Province | Nunavut |
NTS | 48; 58; 68 |
Area | Cornwallis Island; Baffin Island; Brodeur Peninsula; Borden Peninsula; Somerset Island |
Lat/Long WENS | -104.0000 -80.0000 76.0000 72.0000 |
Subjects | surficial geology/geomorphology; icefields; landforms; glacial deposits; glacial erosion; ice; glaciers; meltwater channels; Wisconsinan Glaciation; Quaternary |
Released | 2016 08 18 |
Abstract | Uplands of the Canadian Arctic Islands supported Late Wisconsinan ice caps that developed two landscape zones reflecting basal thermal conditions regulated by long-sustained ice flow patterns. Central
cold-based zones protected older glacial and preglacial landscapes while peripheral warm-based zones scoured and otherwise altered their beds.
Some geomorphic effects are independent of ice cap scale, others vary with scale. For ice caps of 30
km radius or more, scour-zone width remains proportionally constant to flowline length under similar flow conditions. But intensity of scouring, ice moulding of drift and rock eminences, size and abundance of subglacial meltwater features, and
development of end moraines increase with ice cap size.
Ice caps became entirely cold based early in retreat as the boundary between warm and cold ice shifted outward, probably because ice thinned and flow slackened. The frozen margins
deflected meltwater, thus maximizing formation of lateral meltwater channels throughout retreat. The landform record of cold-based glaciers in this region is easily interpreted. Hence, regional ice sheet models invoking or based on the premise that
cold-based ice leaves no geomorphic record seem untenable. |
GEOSCAN ID | 215268 |
|
|