Cosmogenic exposure dating in arctic glacial landscapes: implications for the glacial history of northeastern Baffin Island, Arctic Canada
Cosmogenic exposure dating and detailed glacial-terrain mapping from the Clyde Foreland, Baffin Island, Arctic Canada, reveal new information about the extent and dynamics of the northeastern sector of the Laurentide Ice Sheet (LIS) during the last glacial maximum (LGM). The Clyde Foreland is compos...
Published in: | Canadian Journal of Earth Sciences |
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crcansciencepubl:10.1139/e04-102 2024-06-23T07:49:51+00:00 Cosmogenic exposure dating in arctic glacial landscapes: implications for the glacial history of northeastern Baffin Island, Arctic Canada Briner, Jason P Miller, Gifford H Davis, P Thompson Finkel, Robert C 2005 http://dx.doi.org/10.1139/e04-102 http://www.nrcresearchpress.com/doi/pdf/10.1139/e04-102 en eng Canadian Science Publishing http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining Canadian Journal of Earth Sciences volume 42, issue 1, page 67-84 ISSN 0008-4077 1480-3313 journal-article 2005 crcansciencepubl https://doi.org/10.1139/e04-102 2024-06-13T04:10:52Z Cosmogenic exposure dating and detailed glacial-terrain mapping from the Clyde Foreland, Baffin Island, Arctic Canada, reveal new information about the extent and dynamics of the northeastern sector of the Laurentide Ice Sheet (LIS) during the last glacial maximum (LGM). The Clyde Foreland is composed of two distinct landscape zones: (1) glacially scoured terrain proximal to the major sources of Laurentide ice that flowed onto the foreland, and (2) ice distal unscoured sectors of the foreland. Both zones are draped with erratics and dissected by meltwater channels, indicating past ice cover. We interpret the two landscape classes in terms of ice sheet erosive ability linked with basal thermal regime: glacially scoured terrain was occupied by erosive warm-based ice, and unscoured terrain was last occupied by non-erosive cold-based ice. Cosmogenic exposure ages from >100 erratics from the two landscape types have different age distributions. Cosmogenic exposure ages from the glacially scoured areas suggest ice cover during the LGM, followed by deglaciation between ~15 and ~12 ka. In the unscoured lowlands, the cosmogenic exposure ages have multiple modes ranging between ~12 and ~50 ka, suggesting multiple periods of cold-based ice cover during the last glacial cycle. In landscapes covered by cold-based ice, large numbers of cosmogenic exposure ages are required for elucidating glacial histories. Article in Journal/Newspaper Arctic Baffin Island Baffin Ice Sheet Canadian Science Publishing Arctic Baffin Island Canada Canadian Journal of Earth Sciences 42 1 67 84 |
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Open Polar |
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Canadian Science Publishing |
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crcansciencepubl |
language |
English |
description |
Cosmogenic exposure dating and detailed glacial-terrain mapping from the Clyde Foreland, Baffin Island, Arctic Canada, reveal new information about the extent and dynamics of the northeastern sector of the Laurentide Ice Sheet (LIS) during the last glacial maximum (LGM). The Clyde Foreland is composed of two distinct landscape zones: (1) glacially scoured terrain proximal to the major sources of Laurentide ice that flowed onto the foreland, and (2) ice distal unscoured sectors of the foreland. Both zones are draped with erratics and dissected by meltwater channels, indicating past ice cover. We interpret the two landscape classes in terms of ice sheet erosive ability linked with basal thermal regime: glacially scoured terrain was occupied by erosive warm-based ice, and unscoured terrain was last occupied by non-erosive cold-based ice. Cosmogenic exposure ages from >100 erratics from the two landscape types have different age distributions. Cosmogenic exposure ages from the glacially scoured areas suggest ice cover during the LGM, followed by deglaciation between ~15 and ~12 ka. In the unscoured lowlands, the cosmogenic exposure ages have multiple modes ranging between ~12 and ~50 ka, suggesting multiple periods of cold-based ice cover during the last glacial cycle. In landscapes covered by cold-based ice, large numbers of cosmogenic exposure ages are required for elucidating glacial histories. |
format |
Article in Journal/Newspaper |
author |
Briner, Jason P Miller, Gifford H Davis, P Thompson Finkel, Robert C |
spellingShingle |
Briner, Jason P Miller, Gifford H Davis, P Thompson Finkel, Robert C Cosmogenic exposure dating in arctic glacial landscapes: implications for the glacial history of northeastern Baffin Island, Arctic Canada |
author_facet |
Briner, Jason P Miller, Gifford H Davis, P Thompson Finkel, Robert C |
author_sort |
Briner, Jason P |
title |
Cosmogenic exposure dating in arctic glacial landscapes: implications for the glacial history of northeastern Baffin Island, Arctic Canada |
title_short |
Cosmogenic exposure dating in arctic glacial landscapes: implications for the glacial history of northeastern Baffin Island, Arctic Canada |
title_full |
Cosmogenic exposure dating in arctic glacial landscapes: implications for the glacial history of northeastern Baffin Island, Arctic Canada |
title_fullStr |
Cosmogenic exposure dating in arctic glacial landscapes: implications for the glacial history of northeastern Baffin Island, Arctic Canada |
title_full_unstemmed |
Cosmogenic exposure dating in arctic glacial landscapes: implications for the glacial history of northeastern Baffin Island, Arctic Canada |
title_sort |
cosmogenic exposure dating in arctic glacial landscapes: implications for the glacial history of northeastern baffin island, arctic canada |
publisher |
Canadian Science Publishing |
publishDate |
2005 |
url |
http://dx.doi.org/10.1139/e04-102 http://www.nrcresearchpress.com/doi/pdf/10.1139/e04-102 |
geographic |
Arctic Baffin Island Canada |
geographic_facet |
Arctic Baffin Island Canada |
genre |
Arctic Baffin Island Baffin Ice Sheet |
genre_facet |
Arctic Baffin Island Baffin Ice Sheet |
op_source |
Canadian Journal of Earth Sciences volume 42, issue 1, page 67-84 ISSN 0008-4077 1480-3313 |
op_rights |
http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining |
op_doi |
https://doi.org/10.1139/e04-102 |
container_title |
Canadian Journal of Earth Sciences |
container_volume |
42 |
container_issue |
1 |
container_start_page |
67 |
op_container_end_page |
84 |
_version_ |
1802640530891341824 |