Impact of melting of the Laurentide Ice Sheet on sediments from the upper continental slope off southeastern Canada: evidence from Sm–Nd isotopesThis article is one of a series of papers published in this Special Issue on the theme Polar Climate Stability Network .
We present new Sm–Nd isotope data for sediments from a core located on the continental slope of the St. Pierre Bank of Canada’s east coast. The Nd analyses indicate that the sediments were derived from two principal sources: the North American Shield that yields an average early Proterozoic isotopic...
Published in: | Canadian Journal of Earth Sciences |
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Canadian Science Publishing
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crcansciencepubl:10.1139/e08-031 2023-12-17T10:31:44+01:00 Impact of melting of the Laurentide Ice Sheet on sediments from the upper continental slope off southeastern Canada: evidence from Sm–Nd isotopesThis article is one of a series of papers published in this Special Issue on the theme Polar Climate Stability Network . Stevenson, R. K. Meng, X. W. Hillaire-Marcel, C. Hollings, Pete 2008 http://dx.doi.org/10.1139/e08-031 http://www.nrcresearchpress.com/doi/full-xml/10.1139/E08-031 http://www.nrcresearchpress.com/doi/pdf/10.1139/E08-031 en eng Canadian Science Publishing http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining Canadian Journal of Earth Sciences volume 45, issue 11, page 1243-1252 ISSN 0008-4077 1480-3313 General Earth and Planetary Sciences journal-article 2008 crcansciencepubl https://doi.org/10.1139/e08-031 2023-11-19T13:38:36Z We present new Sm–Nd isotope data for sediments from a core located on the continental slope of the St. Pierre Bank of Canada’s east coast. The Nd analyses indicate that the sediments were derived from two principal sources: the North American Shield that yields an average early Proterozoic isotopic signature and a younger Proterozoic signature attributed to Appalachian crustal sources. The Appalachian-sourced sediments predominated during the last glacial maximum (LGM) and were associated with low sedimentation rates (<30 cm/ka), with the exception of a strong North American Shield signature present in a detrital carbonate layer that corresponds to Heinrich Layer 1 (H1). The dominance of the Appalachian signature decreased subsequent to H1. The Appalachian signatures closely follow the distribution of sediments interpreted as locally derived glacial tills, while the North American Shield signatures follow the distribution of hemipelagic mud that was likely deposited by the Labrador Current. The Nd data are consistent with the persistence of the Wisconsinan Ice Sheet coverage of Newfoundland and the Grand Banks after the LGM, although the coverage began to wane prior to 12.5 ka as evidenced by the increasing influence of the Labrador Current. However, an increase in the Appalachian isotope signature at the close of the Younger Dryas event likely indicates the final melting of the ice sheet covering the Grand Banks and the Avalon Peninsula, and the initiation of the Labrador Current’s modern circulation pathway. Article in Journal/Newspaper Ice Sheet Newfoundland Canadian Science Publishing (via Crossref) Newfoundland Canada Canadian Journal of Earth Sciences 45 11 1243 1252 |
institution |
Open Polar |
collection |
Canadian Science Publishing (via Crossref) |
op_collection_id |
crcansciencepubl |
language |
English |
topic |
General Earth and Planetary Sciences |
spellingShingle |
General Earth and Planetary Sciences Stevenson, R. K. Meng, X. W. Hillaire-Marcel, C. Impact of melting of the Laurentide Ice Sheet on sediments from the upper continental slope off southeastern Canada: evidence from Sm–Nd isotopesThis article is one of a series of papers published in this Special Issue on the theme Polar Climate Stability Network . |
topic_facet |
General Earth and Planetary Sciences |
description |
We present new Sm–Nd isotope data for sediments from a core located on the continental slope of the St. Pierre Bank of Canada’s east coast. The Nd analyses indicate that the sediments were derived from two principal sources: the North American Shield that yields an average early Proterozoic isotopic signature and a younger Proterozoic signature attributed to Appalachian crustal sources. The Appalachian-sourced sediments predominated during the last glacial maximum (LGM) and were associated with low sedimentation rates (<30 cm/ka), with the exception of a strong North American Shield signature present in a detrital carbonate layer that corresponds to Heinrich Layer 1 (H1). The dominance of the Appalachian signature decreased subsequent to H1. The Appalachian signatures closely follow the distribution of sediments interpreted as locally derived glacial tills, while the North American Shield signatures follow the distribution of hemipelagic mud that was likely deposited by the Labrador Current. The Nd data are consistent with the persistence of the Wisconsinan Ice Sheet coverage of Newfoundland and the Grand Banks after the LGM, although the coverage began to wane prior to 12.5 ka as evidenced by the increasing influence of the Labrador Current. However, an increase in the Appalachian isotope signature at the close of the Younger Dryas event likely indicates the final melting of the ice sheet covering the Grand Banks and the Avalon Peninsula, and the initiation of the Labrador Current’s modern circulation pathway. |
author2 |
Hollings, Pete |
format |
Article in Journal/Newspaper |
author |
Stevenson, R. K. Meng, X. W. Hillaire-Marcel, C. |
author_facet |
Stevenson, R. K. Meng, X. W. Hillaire-Marcel, C. |
author_sort |
Stevenson, R. K. |
title |
Impact of melting of the Laurentide Ice Sheet on sediments from the upper continental slope off southeastern Canada: evidence from Sm–Nd isotopesThis article is one of a series of papers published in this Special Issue on the theme Polar Climate Stability Network . |
title_short |
Impact of melting of the Laurentide Ice Sheet on sediments from the upper continental slope off southeastern Canada: evidence from Sm–Nd isotopesThis article is one of a series of papers published in this Special Issue on the theme Polar Climate Stability Network . |
title_full |
Impact of melting of the Laurentide Ice Sheet on sediments from the upper continental slope off southeastern Canada: evidence from Sm–Nd isotopesThis article is one of a series of papers published in this Special Issue on the theme Polar Climate Stability Network . |
title_fullStr |
Impact of melting of the Laurentide Ice Sheet on sediments from the upper continental slope off southeastern Canada: evidence from Sm–Nd isotopesThis article is one of a series of papers published in this Special Issue on the theme Polar Climate Stability Network . |
title_full_unstemmed |
Impact of melting of the Laurentide Ice Sheet on sediments from the upper continental slope off southeastern Canada: evidence from Sm–Nd isotopesThis article is one of a series of papers published in this Special Issue on the theme Polar Climate Stability Network . |
title_sort |
impact of melting of the laurentide ice sheet on sediments from the upper continental slope off southeastern canada: evidence from sm–nd isotopesthis article is one of a series of papers published in this special issue on the theme polar climate stability network . |
publisher |
Canadian Science Publishing |
publishDate |
2008 |
url |
http://dx.doi.org/10.1139/e08-031 http://www.nrcresearchpress.com/doi/full-xml/10.1139/E08-031 http://www.nrcresearchpress.com/doi/pdf/10.1139/E08-031 |
geographic |
Newfoundland Canada |
geographic_facet |
Newfoundland Canada |
genre |
Ice Sheet Newfoundland |
genre_facet |
Ice Sheet Newfoundland |
op_source |
Canadian Journal of Earth Sciences volume 45, issue 11, page 1243-1252 ISSN 0008-4077 1480-3313 |
op_rights |
http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining |
op_doi |
https://doi.org/10.1139/e08-031 |
container_title |
Canadian Journal of Earth Sciences |
container_volume |
45 |
container_issue |
11 |
container_start_page |
1243 |
op_container_end_page |
1252 |
_version_ |
1785585133886111744 |