Ice-rafted detritus events in the Arctic during the last glacial interval, and the timing of the Innuitian and Laurentide ice sheet calving events
Ice-rafted detritus (IRD) layers in the Arctic Ocean not only indicate the source of this detrital sediment, but give insights into the ice drift and ice sheet history. Detrital sand-sized Fe oxide mineral grains that are matched to precise sources using the microprobe chemical fingerprint of each g...
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Norwegian Polar Institute
2008
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ftjpolarres:oai:journals.openacademia.net:article/2877 2023-05-15T14:24:18+02:00 Ice-rafted detritus events in the Arctic during the last glacial interval, and the timing of the Innuitian and Laurentide ice sheet calving events Darby, Dennis A. Zimmerman, Paula 2008-08-01 application/pdf https://polarresearch.net/index.php/polar/article/view/2877 https://doi.org/10.3402/polar.v27i2.6170 eng eng Norwegian Polar Institute https://polarresearch.net/index.php/polar/article/view/2877/6504 https://polarresearch.net/index.php/polar/article/view/2877 doi:10.3402/polar.v27i2.6170 Copyright (c) 2018 Polar Research Polar Research; Vol. 27 No. 2 (2008): Special issue: Arctic Palaeoclimate and its Extremes (APEX); 114-127 1751-8369 info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion 2008 ftjpolarres https://doi.org/10.3402/polar.v27i2.6170 2021-11-11T19:13:21Z Ice-rafted detritus (IRD) layers in the Arctic Ocean not only indicate the source of this detrital sediment, but give insights into the ice drift and ice sheet history. Detrital sand-sized Fe oxide mineral grains that are matched to precise sources using the microprobe chemical fingerprint of each grain, along with elevated coarse IRD abundance and radiocarbon ages, are used to define IRD peaks from the Innuitian and Arctic portions of the Laurentide ice sheets. Because grains from these two areas can be entrained by sea ice from the shelves just offshore of the calving areas, peaks in these grains must be correlated to coarse IRD to identify iceberg calving events, and to distinguish them from sea-ice rafting. The sequence of IRD peaks deposited by icebergs from these two ice sheets indicate that both ice sheets calved bergs at accelerated numbers, six or seven times, from 11 to 36 Kya. The relatively short times between most of these IRD events suggest that the ice sheets did not completely collapse with each IRD event, except the last event. Although there is some indication that one ice sheet may have begun calving bergs before the other, the resolution of the Arctic cores does not allow definitive determination of this. This emphasizes the need for higher resolution cores from the central Arctic, as well as from near the terminus of large Pleistocene ice sheets. Sea-ice rafting occurs throughout the last glacial stage, even during some glacial IRD events, as indicated by Fe grains from non-glacial sources. Article in Journal/Newspaper Arctic Arctic Arctic Ocean Ice Sheet Iceberg* Polar Research Sea ice Polar Research (E-Journal) Arctic Arctic Ocean Kya ENVELOPE(8.308,8.308,63.772,63.772) Polar Research 27 2 |
institution |
Open Polar |
collection |
Polar Research (E-Journal) |
op_collection_id |
ftjpolarres |
language |
English |
description |
Ice-rafted detritus (IRD) layers in the Arctic Ocean not only indicate the source of this detrital sediment, but give insights into the ice drift and ice sheet history. Detrital sand-sized Fe oxide mineral grains that are matched to precise sources using the microprobe chemical fingerprint of each grain, along with elevated coarse IRD abundance and radiocarbon ages, are used to define IRD peaks from the Innuitian and Arctic portions of the Laurentide ice sheets. Because grains from these two areas can be entrained by sea ice from the shelves just offshore of the calving areas, peaks in these grains must be correlated to coarse IRD to identify iceberg calving events, and to distinguish them from sea-ice rafting. The sequence of IRD peaks deposited by icebergs from these two ice sheets indicate that both ice sheets calved bergs at accelerated numbers, six or seven times, from 11 to 36 Kya. The relatively short times between most of these IRD events suggest that the ice sheets did not completely collapse with each IRD event, except the last event. Although there is some indication that one ice sheet may have begun calving bergs before the other, the resolution of the Arctic cores does not allow definitive determination of this. This emphasizes the need for higher resolution cores from the central Arctic, as well as from near the terminus of large Pleistocene ice sheets. Sea-ice rafting occurs throughout the last glacial stage, even during some glacial IRD events, as indicated by Fe grains from non-glacial sources. |
format |
Article in Journal/Newspaper |
author |
Darby, Dennis A. Zimmerman, Paula |
spellingShingle |
Darby, Dennis A. Zimmerman, Paula Ice-rafted detritus events in the Arctic during the last glacial interval, and the timing of the Innuitian and Laurentide ice sheet calving events |
author_facet |
Darby, Dennis A. Zimmerman, Paula |
author_sort |
Darby, Dennis A. |
title |
Ice-rafted detritus events in the Arctic during the last glacial interval, and the timing of the Innuitian and Laurentide ice sheet calving events |
title_short |
Ice-rafted detritus events in the Arctic during the last glacial interval, and the timing of the Innuitian and Laurentide ice sheet calving events |
title_full |
Ice-rafted detritus events in the Arctic during the last glacial interval, and the timing of the Innuitian and Laurentide ice sheet calving events |
title_fullStr |
Ice-rafted detritus events in the Arctic during the last glacial interval, and the timing of the Innuitian and Laurentide ice sheet calving events |
title_full_unstemmed |
Ice-rafted detritus events in the Arctic during the last glacial interval, and the timing of the Innuitian and Laurentide ice sheet calving events |
title_sort |
ice-rafted detritus events in the arctic during the last glacial interval, and the timing of the innuitian and laurentide ice sheet calving events |
publisher |
Norwegian Polar Institute |
publishDate |
2008 |
url |
https://polarresearch.net/index.php/polar/article/view/2877 https://doi.org/10.3402/polar.v27i2.6170 |
long_lat |
ENVELOPE(8.308,8.308,63.772,63.772) |
geographic |
Arctic Arctic Ocean Kya |
geographic_facet |
Arctic Arctic Ocean Kya |
genre |
Arctic Arctic Arctic Ocean Ice Sheet Iceberg* Polar Research Sea ice |
genre_facet |
Arctic Arctic Arctic Ocean Ice Sheet Iceberg* Polar Research Sea ice |
op_source |
Polar Research; Vol. 27 No. 2 (2008): Special issue: Arctic Palaeoclimate and its Extremes (APEX); 114-127 1751-8369 |
op_relation |
https://polarresearch.net/index.php/polar/article/view/2877/6504 https://polarresearch.net/index.php/polar/article/view/2877 doi:10.3402/polar.v27i2.6170 |
op_rights |
Copyright (c) 2018 Polar Research |
op_doi |
https://doi.org/10.3402/polar.v27i2.6170 |
container_title |
Polar Research |
container_volume |
27 |
container_issue |
2 |
_version_ |
1766296730583695360 |