Morphology of the Ice-sheet Margin Near Thule, Greenland
Three types of glacier margin are found along the edge of the Greenland ice sheet near Thule: ice cliffs, ramps and ice-cored moraines. Where the glacier margin is perpendicular to prevailing katabatic winds, drifting snow accumulates along it in stagnant wind-drill ice wedges. Upward flow of active...
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Language: | English |
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Cambridge University Press (CUP)
1970
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Online Access: | http://dx.doi.org/10.1017/s0022143000022851 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000022851 |
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crcambridgeupr:10.1017/s0022143000022851 2024-09-15T18:07:38+00:00 Morphology of the Ice-sheet Margin Near Thule, Greenland Hooke, Roger Leb. 1970 http://dx.doi.org/10.1017/s0022143000022851 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000022851 en eng Cambridge University Press (CUP) Journal of Glaciology volume 9, issue 57, page 303-324 ISSN 0022-1430 1727-5652 journal-article 1970 crcambridgeupr https://doi.org/10.1017/s0022143000022851 2024-07-31T04:04:20Z Three types of glacier margin are found along the edge of the Greenland ice sheet near Thule: ice cliffs, ramps and ice-cored moraines. Where the glacier margin is perpendicular to prevailing katabatic winds, drifting snow accumulates along it in stagnant wind-drill ice wedges. Upward flow of active ice behind these wedges causes ice originally near the base of the glacier to rise to the surface. Where this basal ice is free of debris, a gently sloping ramp develops. However, where the basal ice contains sufficient debris, a layer of till accumulates on the glacier surface. Ice beneath the till is insulated and a debris-capped ice ridge or ice-cored moraine forms, Ice cliffs occur where the ice-sheet margin is parallel to prevailing winds and is thus swept clear of drifting snow. Although the ice sheet in the Thule area appears to have had a negative mass balance for many years, all three types of glacier margin are believed to be equilibrium forms that can develop and persist on a glacier with a balanced mass budget. Foliation in wind-drift ice wedges generally dips down-glacier but foliation in active ice dips up-glacier. It is inferred that foliation in the wedges was once sedimentary stratification that has been tipped upward and locally overturned. Article in Journal/Newspaper glacier Greenland Ice Sheet Journal of Glaciology Thule Cambridge University Press Journal of Glaciology 9 57 303 324 |
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Open Polar |
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Cambridge University Press |
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crcambridgeupr |
language |
English |
description |
Three types of glacier margin are found along the edge of the Greenland ice sheet near Thule: ice cliffs, ramps and ice-cored moraines. Where the glacier margin is perpendicular to prevailing katabatic winds, drifting snow accumulates along it in stagnant wind-drill ice wedges. Upward flow of active ice behind these wedges causes ice originally near the base of the glacier to rise to the surface. Where this basal ice is free of debris, a gently sloping ramp develops. However, where the basal ice contains sufficient debris, a layer of till accumulates on the glacier surface. Ice beneath the till is insulated and a debris-capped ice ridge or ice-cored moraine forms, Ice cliffs occur where the ice-sheet margin is parallel to prevailing winds and is thus swept clear of drifting snow. Although the ice sheet in the Thule area appears to have had a negative mass balance for many years, all three types of glacier margin are believed to be equilibrium forms that can develop and persist on a glacier with a balanced mass budget. Foliation in wind-drift ice wedges generally dips down-glacier but foliation in active ice dips up-glacier. It is inferred that foliation in the wedges was once sedimentary stratification that has been tipped upward and locally overturned. |
format |
Article in Journal/Newspaper |
author |
Hooke, Roger Leb. |
spellingShingle |
Hooke, Roger Leb. Morphology of the Ice-sheet Margin Near Thule, Greenland |
author_facet |
Hooke, Roger Leb. |
author_sort |
Hooke, Roger Leb. |
title |
Morphology of the Ice-sheet Margin Near Thule, Greenland |
title_short |
Morphology of the Ice-sheet Margin Near Thule, Greenland |
title_full |
Morphology of the Ice-sheet Margin Near Thule, Greenland |
title_fullStr |
Morphology of the Ice-sheet Margin Near Thule, Greenland |
title_full_unstemmed |
Morphology of the Ice-sheet Margin Near Thule, Greenland |
title_sort |
morphology of the ice-sheet margin near thule, greenland |
publisher |
Cambridge University Press (CUP) |
publishDate |
1970 |
url |
http://dx.doi.org/10.1017/s0022143000022851 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000022851 |
genre |
glacier Greenland Ice Sheet Journal of Glaciology Thule |
genre_facet |
glacier Greenland Ice Sheet Journal of Glaciology Thule |
op_source |
Journal of Glaciology volume 9, issue 57, page 303-324 ISSN 0022-1430 1727-5652 |
op_doi |
https://doi.org/10.1017/s0022143000022851 |
container_title |
Journal of Glaciology |
container_volume |
9 |
container_issue |
57 |
container_start_page |
303 |
op_container_end_page |
324 |
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1810445013784461312 |