Late Wisconsinan and Holocene History of the Laurentide Ice Sheet
Eleven paleogeographic maps and a summary ice retreat map outline the history of advance, retreat, and readvances of the Laurentide Ice Sheet along with associated changes in proglacial drainage and relative sea level oscillations for Late Wisconsinan and Holocene times. The text outlines pertinent...
Published in: | Géographie physique et Quaternaire |
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Les Presses de l'Université de Montréal
1987
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Online Access: | http://id.erudit.org/iderudit/032681ar https://doi.org/10.7202/032681ar |
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fterudit:oai:erudit.org:032681ar 2023-05-15T16:40:11+02:00 Late Wisconsinan and Holocene History of the Laurentide Ice Sheet Dyke, Arthur S. Prest, Victor K. 1987 http://id.erudit.org/iderudit/032681ar https://doi.org/10.7202/032681ar en eng Les Presses de l'Université de Montréal Érudit Géographie physique et Quaternaire vol. 41 no. 2 (1987) http://id.erudit.org/iderudit/032681ar doi:10.7202/032681ar Tous droits réservés © Les Presses de l'Université de Montréal, 1987 text 1987 fterudit https://doi.org/10.7202/032681ar 2022-09-24T23:13:39Z Eleven paleogeographic maps and a summary ice retreat map outline the history of advance, retreat, and readvances of the Laurentide Ice Sheet along with associated changes in proglacial drainage and relative sea level oscillations for Late Wisconsinan and Holocene times. The text outlines pertinent chronological control and discusses the paleoglaciology of the ice sheet, with attention to location and migration of ice divides, their attendant domes and saddles, and to ice streams, ice shelves, and mechanisms of déglaciation. At 18 ka the ice sheet consisted of 3 sectors with an interlocked system of ice divides joined at intersector saddles. A throughgoing superdivide is recognized and named the Trans Laurentide Ice Divide. The ice sheet retreated slowly from 18 to 13 ka, mainly along the west and south margins, but still held a near maximum configuration at 13 ka. A regional change in flow pattern over the Prairies just before 14 ka is thought to represent a large reduction in ice volume, but not in extent, and likely was triggered by a switch from nondeforming to deforming bed conditions. Retreat between 13 and 8 ka was vastly more rapid in the west than in the east, which resulted in eastward migration of the divide system of Keewatin Ice but relatively static divides of Labrador and Foxe Ice. By 10 ka the Trans Laurentide Ice Divide had been fragmented as Hudson Ice became increasingly autonomous. By 8 ka Hudson Ice had disappeared, little ice was left in Keewatin, but Foxe Ice still held its near maximum configuration and Labrador Ice was still larger than Foxe Ice. Repeated surging along aquatic margins and calving back of margins thinned by surging probably was the most important mechanism of deglaciation of Keewatin and Hudson Ice. The core of Foxe Ice disintegrated at 7 ka but retreat and readvance of Foxe Ice remnants continued throughout the Holocene. Onze cartes paléogéographiques et une carte sommaire du retrait glaciaire retracent l'évolution de la calotte glaciaire ainsi que les changements ... Text Ice Sheet Ice Shelves Keewatin Érudit.org (Université Montréal) Hudson Géographie physique et Quaternaire 41 2 237 263 |
institution |
Open Polar |
collection |
Érudit.org (Université Montréal) |
op_collection_id |
fterudit |
language |
English |
description |
Eleven paleogeographic maps and a summary ice retreat map outline the history of advance, retreat, and readvances of the Laurentide Ice Sheet along with associated changes in proglacial drainage and relative sea level oscillations for Late Wisconsinan and Holocene times. The text outlines pertinent chronological control and discusses the paleoglaciology of the ice sheet, with attention to location and migration of ice divides, their attendant domes and saddles, and to ice streams, ice shelves, and mechanisms of déglaciation. At 18 ka the ice sheet consisted of 3 sectors with an interlocked system of ice divides joined at intersector saddles. A throughgoing superdivide is recognized and named the Trans Laurentide Ice Divide. The ice sheet retreated slowly from 18 to 13 ka, mainly along the west and south margins, but still held a near maximum configuration at 13 ka. A regional change in flow pattern over the Prairies just before 14 ka is thought to represent a large reduction in ice volume, but not in extent, and likely was triggered by a switch from nondeforming to deforming bed conditions. Retreat between 13 and 8 ka was vastly more rapid in the west than in the east, which resulted in eastward migration of the divide system of Keewatin Ice but relatively static divides of Labrador and Foxe Ice. By 10 ka the Trans Laurentide Ice Divide had been fragmented as Hudson Ice became increasingly autonomous. By 8 ka Hudson Ice had disappeared, little ice was left in Keewatin, but Foxe Ice still held its near maximum configuration and Labrador Ice was still larger than Foxe Ice. Repeated surging along aquatic margins and calving back of margins thinned by surging probably was the most important mechanism of deglaciation of Keewatin and Hudson Ice. The core of Foxe Ice disintegrated at 7 ka but retreat and readvance of Foxe Ice remnants continued throughout the Holocene. Onze cartes paléogéographiques et une carte sommaire du retrait glaciaire retracent l'évolution de la calotte glaciaire ainsi que les changements ... |
format |
Text |
author |
Dyke, Arthur S. Prest, Victor K. |
spellingShingle |
Dyke, Arthur S. Prest, Victor K. Late Wisconsinan and Holocene History of the Laurentide Ice Sheet |
author_facet |
Dyke, Arthur S. Prest, Victor K. |
author_sort |
Dyke, Arthur S. |
title |
Late Wisconsinan and Holocene History of the Laurentide Ice Sheet |
title_short |
Late Wisconsinan and Holocene History of the Laurentide Ice Sheet |
title_full |
Late Wisconsinan and Holocene History of the Laurentide Ice Sheet |
title_fullStr |
Late Wisconsinan and Holocene History of the Laurentide Ice Sheet |
title_full_unstemmed |
Late Wisconsinan and Holocene History of the Laurentide Ice Sheet |
title_sort |
late wisconsinan and holocene history of the laurentide ice sheet |
publisher |
Les Presses de l'Université de Montréal |
publishDate |
1987 |
url |
http://id.erudit.org/iderudit/032681ar https://doi.org/10.7202/032681ar |
geographic |
Hudson |
geographic_facet |
Hudson |
genre |
Ice Sheet Ice Shelves Keewatin |
genre_facet |
Ice Sheet Ice Shelves Keewatin |
op_relation |
Géographie physique et Quaternaire vol. 41 no. 2 (1987) http://id.erudit.org/iderudit/032681ar doi:10.7202/032681ar |
op_rights |
Tous droits réservés © Les Presses de l'Université de Montréal, 1987 |
op_doi |
https://doi.org/10.7202/032681ar |
container_title |
Géographie physique et Quaternaire |
container_volume |
41 |
container_issue |
2 |
container_start_page |
237 |
op_container_end_page |
263 |
_version_ |
1766030558791467008 |