Anatomy of Heinrich Layer 1 and its role in the last deglaciation
X-ray fluorescence (XRF) core scanning and X-ray computed tomography data were measured every 1 mm to study the structure of Heinrich Event 1 during the last deglaciation at International Ocean Discovery Program Site U1308. Heinrich Layer 1 comprises two distinct layers of ice-rafted detritus (IRD),...
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ftunivcam:oai:www.repository.cam.ac.uk:1810/264431 2024-02-04T10:01:03+01:00 Anatomy of Heinrich Layer 1 and its role in the last deglaciation Hodell, DA Nicholl, JA Bontognali, TRR Danino, S Dorador, J Dowdeswell, JA Einsle, J Kuhlmann, H Martrat, B Mleneck-Vautravers, MJ Rodríguez-Tovar, FJ Röhl, U 2017-03-30 application/pdf https://www.repository.cam.ac.uk/handle/1810/264431 https://doi.org/10.17863/CAM.9910 eng eng Wiley http://dx.doi.org/10.1002/2016pa003028 Paleoceanography https://www.repository.cam.ac.uk/handle/1810/264431 doi:10.17863/CAM.9910 37 Earth Sciences 3709 Physical Geography and Environmental Geoscience 3705 Geology Article 2017 ftunivcam https://doi.org/10.17863/CAM.9910 2024-01-11T23:30:20Z X-ray fluorescence (XRF) core scanning and X-ray computed tomography data were measured every 1 mm to study the structure of Heinrich Event 1 during the last deglaciation at International Ocean Discovery Program Site U1308. Heinrich Layer 1 comprises two distinct layers of ice-rafted detritus (IRD), which are rich in detrital carbonate (DC) and poor in foraminifera. Each DC layer consists of poorly sorted, coarse-grained clasts of IRD embedded in a dense, fine-grained matrix of glacial rock flour that is partially cemented. The radiocarbon ages of foraminifera at the base of the two layers indicate a difference of 1400 $^{14}$C years, suggesting that they are two distinct events, but the calendar ages depend upon assumptions made for surface reservoir ages. The double peak indicates at least two distinct stages of discharge of the ice streams that drained the Laurentide Ice Sheet through Hudson Strait during HE1 or, alternatively, the discharge of two independent ice streams containing detrital carbonate. Heinrich Event 1.1 was the larger of the two events and began at ~16.2 ka (15.5–17.1 ka) when the polar North Atlantic was already cold and Atlantic Meridional Overturning Circulation (AMOC) weakened. The younger peak (H1.2) at ~15.1 ka (14.3 to 15.9 ka) was a weaker event than H1.1 that was accompanied by minor cooling. Our results support a complex history for Heinrich Stadial 1 (HS1) with reduction in AMOC during the early part (~20–16.2 ka) possibly driven by melting of European ice sheets, whereas the Laurentide Ice Sheet assumed a greater role during the latter half (~16.2–14.7 ka). This research used data acquired at the XRF Core Scanner Lab at the MARUM–Center for Marine Environmental Sciences, University of Bremen, Germany. This research used samples provided by the International Ocean Discovery Program (IODP). Funding for this research was provided by the UK Natural Environmental Research Council (NERC) to Hodell. The NERC Radiocarbon Facility supported two radiocarbon dates, and Wally Broecker ... Article in Journal/Newspaper Hudson Strait Ice Sheet North Atlantic Apollo - University of Cambridge Repository Hudson Hudson Strait ENVELOPE(-70.000,-70.000,62.000,62.000) |
institution |
Open Polar |
collection |
Apollo - University of Cambridge Repository |
op_collection_id |
ftunivcam |
language |
English |
topic |
37 Earth Sciences 3709 Physical Geography and Environmental Geoscience 3705 Geology |
spellingShingle |
37 Earth Sciences 3709 Physical Geography and Environmental Geoscience 3705 Geology Hodell, DA Nicholl, JA Bontognali, TRR Danino, S Dorador, J Dowdeswell, JA Einsle, J Kuhlmann, H Martrat, B Mleneck-Vautravers, MJ Rodríguez-Tovar, FJ Röhl, U Anatomy of Heinrich Layer 1 and its role in the last deglaciation |
topic_facet |
37 Earth Sciences 3709 Physical Geography and Environmental Geoscience 3705 Geology |
description |
X-ray fluorescence (XRF) core scanning and X-ray computed tomography data were measured every 1 mm to study the structure of Heinrich Event 1 during the last deglaciation at International Ocean Discovery Program Site U1308. Heinrich Layer 1 comprises two distinct layers of ice-rafted detritus (IRD), which are rich in detrital carbonate (DC) and poor in foraminifera. Each DC layer consists of poorly sorted, coarse-grained clasts of IRD embedded in a dense, fine-grained matrix of glacial rock flour that is partially cemented. The radiocarbon ages of foraminifera at the base of the two layers indicate a difference of 1400 $^{14}$C years, suggesting that they are two distinct events, but the calendar ages depend upon assumptions made for surface reservoir ages. The double peak indicates at least two distinct stages of discharge of the ice streams that drained the Laurentide Ice Sheet through Hudson Strait during HE1 or, alternatively, the discharge of two independent ice streams containing detrital carbonate. Heinrich Event 1.1 was the larger of the two events and began at ~16.2 ka (15.5–17.1 ka) when the polar North Atlantic was already cold and Atlantic Meridional Overturning Circulation (AMOC) weakened. The younger peak (H1.2) at ~15.1 ka (14.3 to 15.9 ka) was a weaker event than H1.1 that was accompanied by minor cooling. Our results support a complex history for Heinrich Stadial 1 (HS1) with reduction in AMOC during the early part (~20–16.2 ka) possibly driven by melting of European ice sheets, whereas the Laurentide Ice Sheet assumed a greater role during the latter half (~16.2–14.7 ka). This research used data acquired at the XRF Core Scanner Lab at the MARUM–Center for Marine Environmental Sciences, University of Bremen, Germany. This research used samples provided by the International Ocean Discovery Program (IODP). Funding for this research was provided by the UK Natural Environmental Research Council (NERC) to Hodell. The NERC Radiocarbon Facility supported two radiocarbon dates, and Wally Broecker ... |
format |
Article in Journal/Newspaper |
author |
Hodell, DA Nicholl, JA Bontognali, TRR Danino, S Dorador, J Dowdeswell, JA Einsle, J Kuhlmann, H Martrat, B Mleneck-Vautravers, MJ Rodríguez-Tovar, FJ Röhl, U |
author_facet |
Hodell, DA Nicholl, JA Bontognali, TRR Danino, S Dorador, J Dowdeswell, JA Einsle, J Kuhlmann, H Martrat, B Mleneck-Vautravers, MJ Rodríguez-Tovar, FJ Röhl, U |
author_sort |
Hodell, DA |
title |
Anatomy of Heinrich Layer 1 and its role in the last deglaciation |
title_short |
Anatomy of Heinrich Layer 1 and its role in the last deglaciation |
title_full |
Anatomy of Heinrich Layer 1 and its role in the last deglaciation |
title_fullStr |
Anatomy of Heinrich Layer 1 and its role in the last deglaciation |
title_full_unstemmed |
Anatomy of Heinrich Layer 1 and its role in the last deglaciation |
title_sort |
anatomy of heinrich layer 1 and its role in the last deglaciation |
publisher |
Wiley |
publishDate |
2017 |
url |
https://www.repository.cam.ac.uk/handle/1810/264431 https://doi.org/10.17863/CAM.9910 |
long_lat |
ENVELOPE(-70.000,-70.000,62.000,62.000) |
geographic |
Hudson Hudson Strait |
geographic_facet |
Hudson Hudson Strait |
genre |
Hudson Strait Ice Sheet North Atlantic |
genre_facet |
Hudson Strait Ice Sheet North Atlantic |
op_relation |
https://www.repository.cam.ac.uk/handle/1810/264431 doi:10.17863/CAM.9910 |
op_doi |
https://doi.org/10.17863/CAM.9910 |
_version_ |
1789966695728676864 |