Heinrich event-0 (DC-0) in sediment cores from the northwest Labrador Sea: recording events in Cumberland Sound?
Layers of ice-rafted, limestone debris rich sediment were deposited in the northwest Labrador Sea and the North Atlantic during the last glacial period (10-80 ka); these sediments were deposited by Heinrich events (H), events which record catastrophic collapses of the Laurentide Ice Sheet in the reg...
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crcansciencepubl:10.1139/e97-119 2023-12-17T10:29:19+01:00 Heinrich event-0 (DC-0) in sediment cores from the northwest Labrador Sea: recording events in Cumberland Sound? Kirby, Matthew E 1998 http://dx.doi.org/10.1139/e97-119 http://www.nrcresearchpress.com/doi/pdf/10.1139/e97-119 en eng Canadian Science Publishing http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining Canadian Journal of Earth Sciences volume 35, issue 5, page 510-519 ISSN 0008-4077 1480-3313 General Earth and Planetary Sciences journal-article 1998 crcansciencepubl https://doi.org/10.1139/e97-119 2023-11-19T13:38:21Z Layers of ice-rafted, limestone debris rich sediment were deposited in the northwest Labrador Sea and the North Atlantic during the last glacial period (10-80 ka); these sediments were deposited by Heinrich events (H), events which record catastrophic collapses of the Laurentide Ice Sheet in the region of the Hudson Strait. These intervals of detrital carbonate rich sediments are referred to as detrital carbonate layers (DC) in the northwest Labrador Sea. Accelerator mass spectrometry (AMS) 14 C dates provide a strong constraint on the timing for these events; H-1 = DC-1 and H-2 = DC-2. DC-0, also known as H-0, correlative to the Younger Dryas cooling event, is not as distinct a sediment unit in the northwest Labrador Sea as DC-1 and DC-2. An analysis of sediments from two cores (HU75009-IV-055 and HU75009-IV-056) off the mouth of the Hudson Strait in the northwest Labrador Sea basin sheds new light on the "missing" DC-0 sediment unit. Timing for the DC-0 event in cores 055 and 056 is bracketed between 11.3 ka ± 105 years and 10.4 ka ± 185 years based on AMS 14 C dates. Sedimentology of the DC-0 unit reveals a sediment layer rich in ice-rafted debris with an increase in percentage of dolomite (representative material <2 mm), clay-size dolomite, and kaolinite; it is significantly different from DC-1 and DC-2 in the same analyzed cores. For example, the percent carbonate increase in DC-1 and DC-2 is approximately three to four times higher than that in DC-0. In addition, DC-1 and DC-2 show clear evidence for mass sediment transport processes which are not observed in DC-0. From these data, the DC-0 sediment unit in the northwest Labrador Sea records Cumberland Sound ice margin change and, for reasons addressed in this paper, the Hudson Strait does not play a major role in the deposition of DC-0 sediments at these core sites. Provenance indicators, such as kaolinite and dolomite, from the core study sediments corroborate this hypothesis. These results provide strong evidence for Cumberland Sound ice margin ... Article in Journal/Newspaper Cumberland Sound Hudson Strait Ice Sheet Labrador Sea North Atlantic Canadian Science Publishing (via Crossref) Hudson Hudson Strait ENVELOPE(-70.000,-70.000,62.000,62.000) Cumberland Sound ENVELOPE(-66.014,-66.014,65.334,65.334) Canadian Journal of Earth Sciences 35 5 510 519 |
institution |
Open Polar |
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Canadian Science Publishing (via Crossref) |
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crcansciencepubl |
language |
English |
topic |
General Earth and Planetary Sciences |
spellingShingle |
General Earth and Planetary Sciences Kirby, Matthew E Heinrich event-0 (DC-0) in sediment cores from the northwest Labrador Sea: recording events in Cumberland Sound? |
topic_facet |
General Earth and Planetary Sciences |
description |
Layers of ice-rafted, limestone debris rich sediment were deposited in the northwest Labrador Sea and the North Atlantic during the last glacial period (10-80 ka); these sediments were deposited by Heinrich events (H), events which record catastrophic collapses of the Laurentide Ice Sheet in the region of the Hudson Strait. These intervals of detrital carbonate rich sediments are referred to as detrital carbonate layers (DC) in the northwest Labrador Sea. Accelerator mass spectrometry (AMS) 14 C dates provide a strong constraint on the timing for these events; H-1 = DC-1 and H-2 = DC-2. DC-0, also known as H-0, correlative to the Younger Dryas cooling event, is not as distinct a sediment unit in the northwest Labrador Sea as DC-1 and DC-2. An analysis of sediments from two cores (HU75009-IV-055 and HU75009-IV-056) off the mouth of the Hudson Strait in the northwest Labrador Sea basin sheds new light on the "missing" DC-0 sediment unit. Timing for the DC-0 event in cores 055 and 056 is bracketed between 11.3 ka ± 105 years and 10.4 ka ± 185 years based on AMS 14 C dates. Sedimentology of the DC-0 unit reveals a sediment layer rich in ice-rafted debris with an increase in percentage of dolomite (representative material <2 mm), clay-size dolomite, and kaolinite; it is significantly different from DC-1 and DC-2 in the same analyzed cores. For example, the percent carbonate increase in DC-1 and DC-2 is approximately three to four times higher than that in DC-0. In addition, DC-1 and DC-2 show clear evidence for mass sediment transport processes which are not observed in DC-0. From these data, the DC-0 sediment unit in the northwest Labrador Sea records Cumberland Sound ice margin change and, for reasons addressed in this paper, the Hudson Strait does not play a major role in the deposition of DC-0 sediments at these core sites. Provenance indicators, such as kaolinite and dolomite, from the core study sediments corroborate this hypothesis. These results provide strong evidence for Cumberland Sound ice margin ... |
format |
Article in Journal/Newspaper |
author |
Kirby, Matthew E |
author_facet |
Kirby, Matthew E |
author_sort |
Kirby, Matthew E |
title |
Heinrich event-0 (DC-0) in sediment cores from the northwest Labrador Sea: recording events in Cumberland Sound? |
title_short |
Heinrich event-0 (DC-0) in sediment cores from the northwest Labrador Sea: recording events in Cumberland Sound? |
title_full |
Heinrich event-0 (DC-0) in sediment cores from the northwest Labrador Sea: recording events in Cumberland Sound? |
title_fullStr |
Heinrich event-0 (DC-0) in sediment cores from the northwest Labrador Sea: recording events in Cumberland Sound? |
title_full_unstemmed |
Heinrich event-0 (DC-0) in sediment cores from the northwest Labrador Sea: recording events in Cumberland Sound? |
title_sort |
heinrich event-0 (dc-0) in sediment cores from the northwest labrador sea: recording events in cumberland sound? |
publisher |
Canadian Science Publishing |
publishDate |
1998 |
url |
http://dx.doi.org/10.1139/e97-119 http://www.nrcresearchpress.com/doi/pdf/10.1139/e97-119 |
long_lat |
ENVELOPE(-70.000,-70.000,62.000,62.000) ENVELOPE(-66.014,-66.014,65.334,65.334) |
geographic |
Hudson Hudson Strait Cumberland Sound |
geographic_facet |
Hudson Hudson Strait Cumberland Sound |
genre |
Cumberland Sound Hudson Strait Ice Sheet Labrador Sea North Atlantic |
genre_facet |
Cumberland Sound Hudson Strait Ice Sheet Labrador Sea North Atlantic |
op_source |
Canadian Journal of Earth Sciences volume 35, issue 5, page 510-519 ISSN 0008-4077 1480-3313 |
op_rights |
http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining |
op_doi |
https://doi.org/10.1139/e97-119 |
container_title |
Canadian Journal of Earth Sciences |
container_volume |
35 |
container_issue |
5 |
container_start_page |
510 |
op_container_end_page |
519 |
_version_ |
1785581670868451328 |