Sediments, sedimentation rates, and environments, southeast Baffin Shelf and northwest Labrador Sea, 8–26 ka
Ten 14 C-dated cores are described from the Labrador Sea, continental slope, and Hatton and Resolution basins on the southeast Baffin Shelf. Based on sharply defined detrital carbonate layers in the Labrador Sea cores, we propose that the Laurentide Ice Sheet reached the shelf break at both 20 and 1...
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Language: | English |
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Canadian Science Publishing
1994
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Online Access: | http://dx.doi.org/10.1139/e94-008 http://www.nrcresearchpress.com/doi/pdf/10.1139/e94-008 |
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crcansciencepubl:10.1139/e94-008 2024-06-23T07:51:30+00:00 Sediments, sedimentation rates, and environments, southeast Baffin Shelf and northwest Labrador Sea, 8–26 ka Andrews, J. T. Tedesco, K. Briggs, W. M. Evans, L. W. 1994 http://dx.doi.org/10.1139/e94-008 http://www.nrcresearchpress.com/doi/pdf/10.1139/e94-008 en eng Canadian Science Publishing http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining Canadian Journal of Earth Sciences volume 31, issue 1, page 90-103 ISSN 0008-4077 1480-3313 journal-article 1994 crcansciencepubl https://doi.org/10.1139/e94-008 2024-06-13T04:10:50Z Ten 14 C-dated cores are described from the Labrador Sea, continental slope, and Hatton and Resolution basins on the southeast Baffin Shelf. Based on sharply defined detrital carbonate layers in the Labrador Sea cores, we propose that the Laurentide Ice Sheet reached the shelf break at both 20 and 15 14 C ka (24.3 and 18.2 sidereal ka) and contributed significant sediment to the northwest Labrador Sea both times; the flux was ± 720 kg/(m 2 ∙ka) during these periods of maximum ice extent. The Laurentide Ice Sheet retreated from its 15 ka position at the shelf break to the inner shelf between 14 and 12 14 C ka. Ice-proximal conditions, recognized by relatively light δ 18 O on near-surface planktonic foraminifera, high detrital carbonate, and benthic foraminiferal faunas (dominated by Elphidium excavatum forma clavata; Cassidulina reniforme), prevailed until at least 10 14 C ka. The ice readvanced toward Resolution Basin and across part of Hatton Basin at 11 14 C ka. Accelerator mass spectrometry dates on core tops indicate that deposition on the shelf virtually ceased by 7 ka and was very low in the northwest Labrador Sea throughout the Holocene. Downcore accelerator mass spectrometry dates indicate that during deglaciation, the loci of depocentres shifted in response to changes in the position of the ice margin. On the southeast Baffin Island shelf net sediment fluxes at the sea floor reached values of over 3000 kg/(m 2 ∙ka) between 12 and 10 14 C ka, of which nearly half was detrital carbonate, principally calcite. Article in Journal/Newspaper Baffin Island Baffin Ice Sheet Labrador Sea Planktonic foraminifera Canadian Science Publishing Baffin Island Canadian Journal of Earth Sciences 31 1 90 103 |
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Open Polar |
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Canadian Science Publishing |
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crcansciencepubl |
language |
English |
description |
Ten 14 C-dated cores are described from the Labrador Sea, continental slope, and Hatton and Resolution basins on the southeast Baffin Shelf. Based on sharply defined detrital carbonate layers in the Labrador Sea cores, we propose that the Laurentide Ice Sheet reached the shelf break at both 20 and 15 14 C ka (24.3 and 18.2 sidereal ka) and contributed significant sediment to the northwest Labrador Sea both times; the flux was ± 720 kg/(m 2 ∙ka) during these periods of maximum ice extent. The Laurentide Ice Sheet retreated from its 15 ka position at the shelf break to the inner shelf between 14 and 12 14 C ka. Ice-proximal conditions, recognized by relatively light δ 18 O on near-surface planktonic foraminifera, high detrital carbonate, and benthic foraminiferal faunas (dominated by Elphidium excavatum forma clavata; Cassidulina reniforme), prevailed until at least 10 14 C ka. The ice readvanced toward Resolution Basin and across part of Hatton Basin at 11 14 C ka. Accelerator mass spectrometry dates on core tops indicate that deposition on the shelf virtually ceased by 7 ka and was very low in the northwest Labrador Sea throughout the Holocene. Downcore accelerator mass spectrometry dates indicate that during deglaciation, the loci of depocentres shifted in response to changes in the position of the ice margin. On the southeast Baffin Island shelf net sediment fluxes at the sea floor reached values of over 3000 kg/(m 2 ∙ka) between 12 and 10 14 C ka, of which nearly half was detrital carbonate, principally calcite. |
format |
Article in Journal/Newspaper |
author |
Andrews, J. T. Tedesco, K. Briggs, W. M. Evans, L. W. |
spellingShingle |
Andrews, J. T. Tedesco, K. Briggs, W. M. Evans, L. W. Sediments, sedimentation rates, and environments, southeast Baffin Shelf and northwest Labrador Sea, 8–26 ka |
author_facet |
Andrews, J. T. Tedesco, K. Briggs, W. M. Evans, L. W. |
author_sort |
Andrews, J. T. |
title |
Sediments, sedimentation rates, and environments, southeast Baffin Shelf and northwest Labrador Sea, 8–26 ka |
title_short |
Sediments, sedimentation rates, and environments, southeast Baffin Shelf and northwest Labrador Sea, 8–26 ka |
title_full |
Sediments, sedimentation rates, and environments, southeast Baffin Shelf and northwest Labrador Sea, 8–26 ka |
title_fullStr |
Sediments, sedimentation rates, and environments, southeast Baffin Shelf and northwest Labrador Sea, 8–26 ka |
title_full_unstemmed |
Sediments, sedimentation rates, and environments, southeast Baffin Shelf and northwest Labrador Sea, 8–26 ka |
title_sort |
sediments, sedimentation rates, and environments, southeast baffin shelf and northwest labrador sea, 8–26 ka |
publisher |
Canadian Science Publishing |
publishDate |
1994 |
url |
http://dx.doi.org/10.1139/e94-008 http://www.nrcresearchpress.com/doi/pdf/10.1139/e94-008 |
geographic |
Baffin Island |
geographic_facet |
Baffin Island |
genre |
Baffin Island Baffin Ice Sheet Labrador Sea Planktonic foraminifera |
genre_facet |
Baffin Island Baffin Ice Sheet Labrador Sea Planktonic foraminifera |
op_source |
Canadian Journal of Earth Sciences volume 31, issue 1, page 90-103 ISSN 0008-4077 1480-3313 |
op_rights |
http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining |
op_doi |
https://doi.org/10.1139/e94-008 |
container_title |
Canadian Journal of Earth Sciences |
container_volume |
31 |
container_issue |
1 |
container_start_page |
90 |
op_container_end_page |
103 |
_version_ |
1802642599762198528 |