Episodes of Early Pleistocene West Antarctic Ice Sheet Retreat Recorded by Iceberg Alley Sediments
Ice loss in the Southern Hemisphere has been greatest over the past 30 years in West Antarctica. The high sensitivity of this region to climate change has motivated geologists to examine marine sedimentary records for evidence of past episodes of West Antarctic Ice Sheet (WAIS) instability. Sediment...
Published in: | Paleoceanography and Paleoclimatology |
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Main Authors: | , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
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AGU (American Geophysical Union)
2022
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Subjects: | |
Online Access: | https://oceanrep.geomar.de/id/eprint/56721/ https://oceanrep.geomar.de/id/eprint/56721/1/Paleoceanog%20and%20Paleoclimatol%20-%202022%20-%20Bailey%20-%20Episodes%20of%20Early%20Pleistocene%20West%20Antarctic%20Ice%20Sheet%20Retreat%20Recorded%20by.pdf https://oceanrep.geomar.de/id/eprint/56721/2/2022pa004433-sup-0002-movie https://oceanrep.geomar.de/id/eprint/56721/3/2022pa004433-sup-0001-supporting https://doi.org/10.1029/2022PA004433 |
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ftoceanrep:oai:oceanrep.geomar.de:56721 |
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record_format |
openpolar |
institution |
Open Polar |
collection |
OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel) |
op_collection_id |
ftoceanrep |
language |
English |
description |
Ice loss in the Southern Hemisphere has been greatest over the past 30 years in West Antarctica. The high sensitivity of this region to climate change has motivated geologists to examine marine sedimentary records for evidence of past episodes of West Antarctic Ice Sheet (WAIS) instability. Sediments accumulating in the Scotia Sea are useful to examine for this purpose because they receive iceberg-rafted debris (IBRD) sourced from the Pacific- and Atlantic-facing sectors of West Antarctica. Here we report on the sedimentology and provenance of the oldest of three cm-scale coarse-grained layers recovered from this sea at International Ocean Discovery Program Site U1538. These layers are preserved in opal-rich sediments deposited ∼1.2 Ma during a relatively warm regional climate. Our microCT-based analysis of the layer's in-situ fabric confirms its ice-rafted origin. We further infer that it is the product of an intense but short-lived episode of IBRD deposition. Based on the petrography of its sand fraction and the Phanerozoic 40Ar/39Ar ages of hornblende and mica it contains, we conclude that the IBRD it contains was likely sourced from the Weddell Sea and/or Amundsen Sea embayment(s) of West Antarctica. We attribute the high concentrations of IBRD in these layers to “dirty” icebergs calved from the WAIS following its retreat inland from its modern grounding line. These layers also sit at the top of a ∼366-m thick Pliocene and early Pleistocene sequence that is much more dropstone-rich than its overlying sediments. We speculate this fact may reflect that WAIS mass-balance was highly dynamic during the ∼41-kyr (inter)glacial world. Key Points - We present the first provenance data generated for Pleistocene-aged iceberg-rafted debris deposited in Iceberg Alley - We conclude that prominent iceberg-rafted debris layers deposited at Pirie Basin Site U1538 ∼1.2 Ma were sourced from West Antarctica - They represent intense suborbitally-paced episodes of iceberg discharge from tidewater glaciers, most likely in the ... |
format |
Article in Journal/Newspaper |
author |
Bailey, Ian Hemming, Sidney Reilly, Brendan T. Rollinson, Gavyn Williams, Trevor Weber, Michael E. Raymo, Maureen E. Peck, Victoria L. Ronge, Thomas A. Brachfeld, Stefanie O'Connell, Suzanne Tauxe, Lisa Warnock, Jonathan P. Armbrecht, Linda Cardillo, Fabricio G. Du, Zhiheng Fauth, Gerson Garcia, Marga Glueder, Anna Guitard, Michelle Gutjahr, Marcus Hernández‐Almeida, Iván Hoem, Frida S. Hwang, Ji‐Hwan Iizuka, Mutsumi Kato, Yuji Kenlee, Bridget Martos, Yasmina M. Pérez, Lara F. Seki, Osamu Tripathi, Shubham Zheng, Xufeng |
spellingShingle |
Bailey, Ian Hemming, Sidney Reilly, Brendan T. Rollinson, Gavyn Williams, Trevor Weber, Michael E. Raymo, Maureen E. Peck, Victoria L. Ronge, Thomas A. Brachfeld, Stefanie O'Connell, Suzanne Tauxe, Lisa Warnock, Jonathan P. Armbrecht, Linda Cardillo, Fabricio G. Du, Zhiheng Fauth, Gerson Garcia, Marga Glueder, Anna Guitard, Michelle Gutjahr, Marcus Hernández‐Almeida, Iván Hoem, Frida S. Hwang, Ji‐Hwan Iizuka, Mutsumi Kato, Yuji Kenlee, Bridget Martos, Yasmina M. Pérez, Lara F. Seki, Osamu Tripathi, Shubham Zheng, Xufeng Episodes of Early Pleistocene West Antarctic Ice Sheet Retreat Recorded by Iceberg Alley Sediments |
author_facet |
Bailey, Ian Hemming, Sidney Reilly, Brendan T. Rollinson, Gavyn Williams, Trevor Weber, Michael E. Raymo, Maureen E. Peck, Victoria L. Ronge, Thomas A. Brachfeld, Stefanie O'Connell, Suzanne Tauxe, Lisa Warnock, Jonathan P. Armbrecht, Linda Cardillo, Fabricio G. Du, Zhiheng Fauth, Gerson Garcia, Marga Glueder, Anna Guitard, Michelle Gutjahr, Marcus Hernández‐Almeida, Iván Hoem, Frida S. Hwang, Ji‐Hwan Iizuka, Mutsumi Kato, Yuji Kenlee, Bridget Martos, Yasmina M. Pérez, Lara F. Seki, Osamu Tripathi, Shubham Zheng, Xufeng |
author_sort |
Bailey, Ian |
title |
Episodes of Early Pleistocene West Antarctic Ice Sheet Retreat Recorded by Iceberg Alley Sediments |
title_short |
Episodes of Early Pleistocene West Antarctic Ice Sheet Retreat Recorded by Iceberg Alley Sediments |
title_full |
Episodes of Early Pleistocene West Antarctic Ice Sheet Retreat Recorded by Iceberg Alley Sediments |
title_fullStr |
Episodes of Early Pleistocene West Antarctic Ice Sheet Retreat Recorded by Iceberg Alley Sediments |
title_full_unstemmed |
Episodes of Early Pleistocene West Antarctic Ice Sheet Retreat Recorded by Iceberg Alley Sediments |
title_sort |
episodes of early pleistocene west antarctic ice sheet retreat recorded by iceberg alley sediments |
publisher |
AGU (American Geophysical Union) |
publishDate |
2022 |
url |
https://oceanrep.geomar.de/id/eprint/56721/ https://oceanrep.geomar.de/id/eprint/56721/1/Paleoceanog%20and%20Paleoclimatol%20-%202022%20-%20Bailey%20-%20Episodes%20of%20Early%20Pleistocene%20West%20Antarctic%20Ice%20Sheet%20Retreat%20Recorded%20by.pdf https://oceanrep.geomar.de/id/eprint/56721/2/2022pa004433-sup-0002-movie https://oceanrep.geomar.de/id/eprint/56721/3/2022pa004433-sup-0001-supporting https://doi.org/10.1029/2022PA004433 |
long_lat |
ENVELOPE(-44.633,-44.633,-60.700,-60.700) |
geographic |
Antarctic Weddell Sea West Antarctica Scotia Sea Amundsen Sea West Antarctic Ice Sheet Pacific Weddell Pirie |
geographic_facet |
Antarctic Weddell Sea West Antarctica Scotia Sea Amundsen Sea West Antarctic Ice Sheet Pacific Weddell Pirie |
genre |
Amundsen Sea Antarc* Antarctic Antarctica Ice Sheet Iceberg* Scotia Sea Weddell Sea West Antarctica |
genre_facet |
Amundsen Sea Antarc* Antarctic Antarctica Ice Sheet Iceberg* Scotia Sea Weddell Sea West Antarctica |
op_relation |
https://oceanrep.geomar.de/id/eprint/56721/1/Paleoceanog%20and%20Paleoclimatol%20-%202022%20-%20Bailey%20-%20Episodes%20of%20Early%20Pleistocene%20West%20Antarctic%20Ice%20Sheet%20Retreat%20Recorded%20by.pdf https://oceanrep.geomar.de/id/eprint/56721/2/2022pa004433-sup-0002-movie https://oceanrep.geomar.de/id/eprint/56721/3/2022pa004433-sup-0001-supporting Bailey, I., Hemming, S., Reilly, B. T., Rollinson, G., Williams, T., Weber, M. E., Raymo, M. E., Peck, V. L., Ronge, T. A., Brachfeld, S., O'Connell, S., Tauxe, L., Warnock, J. P., Armbrecht, L., Cardillo, F. G., Du, Z., Fauth, G., Garcia, M., Glueder, A., Guitard, M., Gutjahr, M. , Hernández‐Almeida, I., Hoem, F. S., Hwang, J., Iizuka, M., Kato, Y., Kenlee, B., Martos, Y. M., Pérez, L. F., Seki, O., Tripathi, S. and Zheng, X. (2022) Episodes of Early Pleistocene West Antarctic Ice Sheet Retreat Recorded by Iceberg Alley Sediments. Open Access Paleoceanography and Paleoclimatology, 37 (7). Art.Nr. e2022PA004433. DOI 10.1029/2022PA004433 <https://doi.org/10.1029/2022PA004433>. doi:10.1029/2022PA004433 |
op_rights |
cc_by_4.0 info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.1029/2022PA004433 |
container_title |
Paleoceanography and Paleoclimatology |
container_volume |
37 |
container_issue |
7 |
_version_ |
1790595075199205376 |
spelling |
ftoceanrep:oai:oceanrep.geomar.de:56721 2024-02-11T09:55:21+01:00 Episodes of Early Pleistocene West Antarctic Ice Sheet Retreat Recorded by Iceberg Alley Sediments Bailey, Ian Hemming, Sidney Reilly, Brendan T. Rollinson, Gavyn Williams, Trevor Weber, Michael E. Raymo, Maureen E. Peck, Victoria L. Ronge, Thomas A. Brachfeld, Stefanie O'Connell, Suzanne Tauxe, Lisa Warnock, Jonathan P. Armbrecht, Linda Cardillo, Fabricio G. Du, Zhiheng Fauth, Gerson Garcia, Marga Glueder, Anna Guitard, Michelle Gutjahr, Marcus Hernández‐Almeida, Iván Hoem, Frida S. Hwang, Ji‐Hwan Iizuka, Mutsumi Kato, Yuji Kenlee, Bridget Martos, Yasmina M. Pérez, Lara F. Seki, Osamu Tripathi, Shubham Zheng, Xufeng 2022-07-12 text video https://oceanrep.geomar.de/id/eprint/56721/ https://oceanrep.geomar.de/id/eprint/56721/1/Paleoceanog%20and%20Paleoclimatol%20-%202022%20-%20Bailey%20-%20Episodes%20of%20Early%20Pleistocene%20West%20Antarctic%20Ice%20Sheet%20Retreat%20Recorded%20by.pdf https://oceanrep.geomar.de/id/eprint/56721/2/2022pa004433-sup-0002-movie https://oceanrep.geomar.de/id/eprint/56721/3/2022pa004433-sup-0001-supporting https://doi.org/10.1029/2022PA004433 en eng AGU (American Geophysical Union) Wiley https://oceanrep.geomar.de/id/eprint/56721/1/Paleoceanog%20and%20Paleoclimatol%20-%202022%20-%20Bailey%20-%20Episodes%20of%20Early%20Pleistocene%20West%20Antarctic%20Ice%20Sheet%20Retreat%20Recorded%20by.pdf https://oceanrep.geomar.de/id/eprint/56721/2/2022pa004433-sup-0002-movie https://oceanrep.geomar.de/id/eprint/56721/3/2022pa004433-sup-0001-supporting Bailey, I., Hemming, S., Reilly, B. T., Rollinson, G., Williams, T., Weber, M. E., Raymo, M. E., Peck, V. L., Ronge, T. A., Brachfeld, S., O'Connell, S., Tauxe, L., Warnock, J. P., Armbrecht, L., Cardillo, F. G., Du, Z., Fauth, G., Garcia, M., Glueder, A., Guitard, M., Gutjahr, M. , Hernández‐Almeida, I., Hoem, F. S., Hwang, J., Iizuka, M., Kato, Y., Kenlee, B., Martos, Y. M., Pérez, L. F., Seki, O., Tripathi, S. and Zheng, X. (2022) Episodes of Early Pleistocene West Antarctic Ice Sheet Retreat Recorded by Iceberg Alley Sediments. Open Access Paleoceanography and Paleoclimatology, 37 (7). Art.Nr. e2022PA004433. DOI 10.1029/2022PA004433 <https://doi.org/10.1029/2022PA004433>. doi:10.1029/2022PA004433 cc_by_4.0 info:eu-repo/semantics/openAccess Article PeerReviewed 2022 ftoceanrep https://doi.org/10.1029/2022PA004433 2024-01-15T00:25:40Z Ice loss in the Southern Hemisphere has been greatest over the past 30 years in West Antarctica. The high sensitivity of this region to climate change has motivated geologists to examine marine sedimentary records for evidence of past episodes of West Antarctic Ice Sheet (WAIS) instability. Sediments accumulating in the Scotia Sea are useful to examine for this purpose because they receive iceberg-rafted debris (IBRD) sourced from the Pacific- and Atlantic-facing sectors of West Antarctica. Here we report on the sedimentology and provenance of the oldest of three cm-scale coarse-grained layers recovered from this sea at International Ocean Discovery Program Site U1538. These layers are preserved in opal-rich sediments deposited ∼1.2 Ma during a relatively warm regional climate. Our microCT-based analysis of the layer's in-situ fabric confirms its ice-rafted origin. We further infer that it is the product of an intense but short-lived episode of IBRD deposition. Based on the petrography of its sand fraction and the Phanerozoic 40Ar/39Ar ages of hornblende and mica it contains, we conclude that the IBRD it contains was likely sourced from the Weddell Sea and/or Amundsen Sea embayment(s) of West Antarctica. We attribute the high concentrations of IBRD in these layers to “dirty” icebergs calved from the WAIS following its retreat inland from its modern grounding line. These layers also sit at the top of a ∼366-m thick Pliocene and early Pleistocene sequence that is much more dropstone-rich than its overlying sediments. We speculate this fact may reflect that WAIS mass-balance was highly dynamic during the ∼41-kyr (inter)glacial world. Key Points - We present the first provenance data generated for Pleistocene-aged iceberg-rafted debris deposited in Iceberg Alley - We conclude that prominent iceberg-rafted debris layers deposited at Pirie Basin Site U1538 ∼1.2 Ma were sourced from West Antarctica - They represent intense suborbitally-paced episodes of iceberg discharge from tidewater glaciers, most likely in the ... Article in Journal/Newspaper Amundsen Sea Antarc* Antarctic Antarctica Ice Sheet Iceberg* Scotia Sea Weddell Sea West Antarctica OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel) Antarctic Weddell Sea West Antarctica Scotia Sea Amundsen Sea West Antarctic Ice Sheet Pacific Weddell Pirie ENVELOPE(-44.633,-44.633,-60.700,-60.700) Paleoceanography and Paleoclimatology 37 7 |