Timing and pace of ice-sheet withdrawal across the marine–terrestrial transition west of Ireland during the last glaciation
Understanding the pace and drivers of marine‐based ice‐sheet retreat relies upon the integration of numerical ice‐sheet models with observations from contemporary polar ice sheets and well‐constrained palaeo‐glaciological reconstructions. This paper provides a reconstruction of the retreat of the la...
Published in: | Journal of Quaternary Science |
---|---|
Main Authors: | , , , , , , , , , , , , , , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
2021
|
Subjects: | |
Online Access: | https://research-portal.st-andrews.ac.uk/en/researchoutput/timing-and-pace-of-icesheet-withdrawal-across-the-marineterrestrial-transition-west-of-ireland-during-the-last-glaciation(56461ef1-ba17-41f2-8994-b0b463c4803b).html https://doi.org/10.1002/jqs.3295 https://research-repository.st-andrews.ac.uk/bitstream/10023/22990/1/Cofaigh_2021_JQS_timing_pace_CC.pdf https://research-repository.st-andrews.ac.uk/bitstream/10023/22990/2/Cofaigh_2021_JQS_timing_pace_correction_CC.pdf |
id |
ftunstandrewcris:oai:research-portal.st-andrews.ac.uk:publications/56461ef1-ba17-41f2-8994-b0b463c4803b |
---|---|
record_format |
openpolar |
institution |
Open Polar |
collection |
University of St Andrews: Research Portal |
op_collection_id |
ftunstandrewcris |
language |
English |
topic |
British–Irish Ice Sheet Glacimarine sediments Ice sheet extent Ice sheet retreat Last Glacial Maximum Porcupine Bank Radiocarbon dating Subglacial till Western Ireland |
spellingShingle |
British–Irish Ice Sheet Glacimarine sediments Ice sheet extent Ice sheet retreat Last Glacial Maximum Porcupine Bank Radiocarbon dating Subglacial till Western Ireland Ó Cofaigh, Colm Callard, S. Louise Roberts, David H. Chiverrell, Richard C. Ballantyne, C. K. Evans, David J. A. Saher, Margot Van Landeghem, Katrien J. J. Smedley, Rachel Benetti, Sara Burke, Matthew Clark, Chris D. Duller, Geoff A. T. Fabel, Derek Livingstone, Stephen J. Mccarron, Stephen Medialdea, Alicia Moreton, Steven G. Sacchetti, Fabio Timing and pace of ice-sheet withdrawal across the marine–terrestrial transition west of Ireland during the last glaciation |
topic_facet |
British–Irish Ice Sheet Glacimarine sediments Ice sheet extent Ice sheet retreat Last Glacial Maximum Porcupine Bank Radiocarbon dating Subglacial till Western Ireland |
description |
Understanding the pace and drivers of marine‐based ice‐sheet retreat relies upon the integration of numerical ice‐sheet models with observations from contemporary polar ice sheets and well‐constrained palaeo‐glaciological reconstructions. This paper provides a reconstruction of the retreat of the last British–Irish Ice Sheet (BIIS) from the Atlantic shelf west of Ireland during and following the Last Glacial Maximum (LGM). It uses marine‐geophysical data and sediment cores dated by radiocarbon, combined with terrestrial cosmogenic nuclide and optically stimulated luminescence dating of onshore ice‐marginal landforms, to reconstruct the timing and rate of ice‐sheet retreat from the continental shelf and across the adjoining coastline of Ireland, thus including the switch from a marine‐ to a terrestrially‐based ice‐sheet margin. Seafloor bathymetric data in the form of moraines and grounding‐zone wedges on the continental shelf record an extensive ice sheet west of Ireland during the LGM which advanced to the outer shelf. This interpretation is supported by the presence of dated subglacial tills and overridden glacimarine sediments from across the Porcupine Bank, a westwards extension of the Irish continental shelf. The ice sheet was grounded on the outer shelf at ~26.8 ka cal bp with initial retreat underway by 25.9 ka cal bp. Retreat was not a continuous process but was punctuated by marginal oscillations until ~24.3 ka cal bp. The ice sheet thereafter retreated to the mid‐shelf where it formed a large grounding‐zone complex at ~23.7 ka cal bp. This retreat occurred in a glacimarine environment. The Aran Islands on the inner continental shelf were ice‐free by ~19.5 ka bp and the ice sheet had become largely terrestrially based by 17.3 ka bp. This suggests that the Aran Islands acted to stabilize and slow overall ice‐sheet retreat once the BIIS margin had reached the inner shelf. Our results constrain the timing of initial retreat of the BIIS from the outer shelf west of Ireland to the period of minimum global ... |
format |
Article in Journal/Newspaper |
author |
Ó Cofaigh, Colm Callard, S. Louise Roberts, David H. Chiverrell, Richard C. Ballantyne, C. K. Evans, David J. A. Saher, Margot Van Landeghem, Katrien J. J. Smedley, Rachel Benetti, Sara Burke, Matthew Clark, Chris D. Duller, Geoff A. T. Fabel, Derek Livingstone, Stephen J. Mccarron, Stephen Medialdea, Alicia Moreton, Steven G. Sacchetti, Fabio |
author_facet |
Ó Cofaigh, Colm Callard, S. Louise Roberts, David H. Chiverrell, Richard C. Ballantyne, C. K. Evans, David J. A. Saher, Margot Van Landeghem, Katrien J. J. Smedley, Rachel Benetti, Sara Burke, Matthew Clark, Chris D. Duller, Geoff A. T. Fabel, Derek Livingstone, Stephen J. Mccarron, Stephen Medialdea, Alicia Moreton, Steven G. Sacchetti, Fabio |
author_sort |
Ó Cofaigh, Colm |
title |
Timing and pace of ice-sheet withdrawal across the marine–terrestrial transition west of Ireland during the last glaciation |
title_short |
Timing and pace of ice-sheet withdrawal across the marine–terrestrial transition west of Ireland during the last glaciation |
title_full |
Timing and pace of ice-sheet withdrawal across the marine–terrestrial transition west of Ireland during the last glaciation |
title_fullStr |
Timing and pace of ice-sheet withdrawal across the marine–terrestrial transition west of Ireland during the last glaciation |
title_full_unstemmed |
Timing and pace of ice-sheet withdrawal across the marine–terrestrial transition west of Ireland during the last glaciation |
title_sort |
timing and pace of ice-sheet withdrawal across the marine–terrestrial transition west of ireland during the last glaciation |
publishDate |
2021 |
url |
https://research-portal.st-andrews.ac.uk/en/researchoutput/timing-and-pace-of-icesheet-withdrawal-across-the-marineterrestrial-transition-west-of-ireland-during-the-last-glaciation(56461ef1-ba17-41f2-8994-b0b463c4803b).html https://doi.org/10.1002/jqs.3295 https://research-repository.st-andrews.ac.uk/bitstream/10023/22990/1/Cofaigh_2021_JQS_timing_pace_CC.pdf https://research-repository.st-andrews.ac.uk/bitstream/10023/22990/2/Cofaigh_2021_JQS_timing_pace_correction_CC.pdf |
genre |
Ice Sheet |
genre_facet |
Ice Sheet |
op_source |
Ó Cofaigh , C , Callard , S L , Roberts , D H , Chiverrell , R C , Ballantyne , C K , Evans , D J A , Saher , M , Van Landeghem , K J J , Smedley , R , Benetti , S , Burke , M , Clark , C D , Duller , G A T , Fabel , D , Livingstone , S J , Mccarron , S , Medialdea , A , Moreton , S G & Sacchetti , F 2021 , ' Timing and pace of ice-sheet withdrawal across the marine–terrestrial transition west of Ireland during the last glaciation ' , Journal of Quaternary Science , vol. Early View . https://doi.org/10.1002/jqs.3295 |
op_relation |
https://research-portal.st-andrews.ac.uk/en/researchoutput/timing-and-pace-of-icesheet-withdrawal-across-the-marineterrestrial-transition-west-of-ireland-during-the-last-glaciation(56461ef1-ba17-41f2-8994-b0b463c4803b).html |
op_rights |
info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.1002/jqs.3295 |
container_title |
Journal of Quaternary Science |
container_volume |
36 |
container_issue |
5 |
container_start_page |
805 |
op_container_end_page |
832 |
_version_ |
1810449684940980224 |
spelling |
ftunstandrewcris:oai:research-portal.st-andrews.ac.uk:publications/56461ef1-ba17-41f2-8994-b0b463c4803b 2024-09-15T18:12:06+00:00 Timing and pace of ice-sheet withdrawal across the marine–terrestrial transition west of Ireland during the last glaciation Ó Cofaigh, Colm Callard, S. Louise Roberts, David H. Chiverrell, Richard C. Ballantyne, C. K. Evans, David J. A. Saher, Margot Van Landeghem, Katrien J. J. Smedley, Rachel Benetti, Sara Burke, Matthew Clark, Chris D. Duller, Geoff A. T. Fabel, Derek Livingstone, Stephen J. Mccarron, Stephen Medialdea, Alicia Moreton, Steven G. Sacchetti, Fabio 2021-04-07 application/pdf https://research-portal.st-andrews.ac.uk/en/researchoutput/timing-and-pace-of-icesheet-withdrawal-across-the-marineterrestrial-transition-west-of-ireland-during-the-last-glaciation(56461ef1-ba17-41f2-8994-b0b463c4803b).html https://doi.org/10.1002/jqs.3295 https://research-repository.st-andrews.ac.uk/bitstream/10023/22990/1/Cofaigh_2021_JQS_timing_pace_CC.pdf https://research-repository.st-andrews.ac.uk/bitstream/10023/22990/2/Cofaigh_2021_JQS_timing_pace_correction_CC.pdf eng eng https://research-portal.st-andrews.ac.uk/en/researchoutput/timing-and-pace-of-icesheet-withdrawal-across-the-marineterrestrial-transition-west-of-ireland-during-the-last-glaciation(56461ef1-ba17-41f2-8994-b0b463c4803b).html info:eu-repo/semantics/openAccess Ó Cofaigh , C , Callard , S L , Roberts , D H , Chiverrell , R C , Ballantyne , C K , Evans , D J A , Saher , M , Van Landeghem , K J J , Smedley , R , Benetti , S , Burke , M , Clark , C D , Duller , G A T , Fabel , D , Livingstone , S J , Mccarron , S , Medialdea , A , Moreton , S G & Sacchetti , F 2021 , ' Timing and pace of ice-sheet withdrawal across the marine–terrestrial transition west of Ireland during the last glaciation ' , Journal of Quaternary Science , vol. Early View . https://doi.org/10.1002/jqs.3295 British–Irish Ice Sheet Glacimarine sediments Ice sheet extent Ice sheet retreat Last Glacial Maximum Porcupine Bank Radiocarbon dating Subglacial till Western Ireland article 2021 ftunstandrewcris https://doi.org/10.1002/jqs.3295 2024-06-26T23:33:42Z Understanding the pace and drivers of marine‐based ice‐sheet retreat relies upon the integration of numerical ice‐sheet models with observations from contemporary polar ice sheets and well‐constrained palaeo‐glaciological reconstructions. This paper provides a reconstruction of the retreat of the last British–Irish Ice Sheet (BIIS) from the Atlantic shelf west of Ireland during and following the Last Glacial Maximum (LGM). It uses marine‐geophysical data and sediment cores dated by radiocarbon, combined with terrestrial cosmogenic nuclide and optically stimulated luminescence dating of onshore ice‐marginal landforms, to reconstruct the timing and rate of ice‐sheet retreat from the continental shelf and across the adjoining coastline of Ireland, thus including the switch from a marine‐ to a terrestrially‐based ice‐sheet margin. Seafloor bathymetric data in the form of moraines and grounding‐zone wedges on the continental shelf record an extensive ice sheet west of Ireland during the LGM which advanced to the outer shelf. This interpretation is supported by the presence of dated subglacial tills and overridden glacimarine sediments from across the Porcupine Bank, a westwards extension of the Irish continental shelf. The ice sheet was grounded on the outer shelf at ~26.8 ka cal bp with initial retreat underway by 25.9 ka cal bp. Retreat was not a continuous process but was punctuated by marginal oscillations until ~24.3 ka cal bp. The ice sheet thereafter retreated to the mid‐shelf where it formed a large grounding‐zone complex at ~23.7 ka cal bp. This retreat occurred in a glacimarine environment. The Aran Islands on the inner continental shelf were ice‐free by ~19.5 ka bp and the ice sheet had become largely terrestrially based by 17.3 ka bp. This suggests that the Aran Islands acted to stabilize and slow overall ice‐sheet retreat once the BIIS margin had reached the inner shelf. Our results constrain the timing of initial retreat of the BIIS from the outer shelf west of Ireland to the period of minimum global ... Article in Journal/Newspaper Ice Sheet University of St Andrews: Research Portal Journal of Quaternary Science 36 5 805 832 |