Dynamics of former ice lobes of the southernmost Patagonian Ice Sheet based on a glacial landsystems approach
ABSTRACT Reconstructions of former ice masses from glacial geomorphology help to constrain the nature and timing of glaciation in relation to climatic forcing. This paper presents a new reconstruction of the glacial history of five ice lobes in southernmost South America: the Bahía Inútil − San Seba...
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crwiley:10.1002/jqs.2890 2024-09-30T14:36:38+00:00 Dynamics of former ice lobes of the southernmost Patagonian Ice Sheet based on a glacial landsystems approach Darvill, Christopher M. Stokes, Chris R. Bentley, Michael J. Evans, David J. A. Lovell, Harold Explorers Club Natural Resources Wales Durham University 2016 http://dx.doi.org/10.1002/jqs.2890 https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1002%2Fjqs.2890 https://onlinelibrary.wiley.com/doi/pdf/10.1002/jqs.2890 en eng Wiley http://creativecommons.org/licenses/by/4.0/ Journal of Quaternary Science volume 32, issue 6, page 857-876 ISSN 0267-8179 1099-1417 journal-article 2016 crwiley https://doi.org/10.1002/jqs.2890 2024-09-17T04:44:41Z ABSTRACT Reconstructions of former ice masses from glacial geomorphology help to constrain the nature and timing of glaciation in relation to climatic forcing. This paper presents a new reconstruction of the glacial history of five ice lobes in southernmost South America: the Bahía Inútil − San Sebastián, Magellan, Otway, Skyring and Río Gallegos ice lobes. We use previous geomorphological mapping of glacial landforms to reconstruct former glacial limits and proglacial lakes, demarcate flow‐sets from the distribution of glacial lineations, and evaluate glacial landsystem signatures and their palaeoglaciological implications. Evidence suggests that the ice lobes predominantly reflect active temperate glacial landsystems, which may have switched to polythermal systems when periods of cold‐based ice developed ephemerally. This complex landsystem signature implies that the ice lobes were sensitive to regional climate variability, with active re‐advances during overall retreat of the ice margins. There is also evidence for periods of fast ice flow and possible surge‐like activity in the region, followed by the rapid retreat or even collapse of some of the ice lobes in association with proglacial lakes. Constraining our new reconstruction with published chronological information suggests that at least some of the ice lobes advanced before the global Last Glacial Maximum (gLGM: ca. 26.5–19 ka) during the last glacial cycle. Our new reconstruction demonstrates a more complex picture of ice dynamics than has previously been portrayed, and one in which the advance and retreat of the ice lobes was likely to have been primarily driven by changes in climate. As such, ice advances before the gLGM in the southernmost part of the Patagonian Ice Sheet are likely to indicate a wider climatic forcing at this time. Article in Journal/Newspaper Ice Sheet Wiley Online Library Gallegos ENVELOPE(-67.150,-67.150,-68.133,-68.133) Inútil ENVELOPE(-60.783,-60.783,-64.050,-64.050) bahía Inútil ENVELOPE(-62.917,-62.917,-64.883,-64.883) Journal of Quaternary Science 32 6 857 876 |
institution |
Open Polar |
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Wiley Online Library |
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crwiley |
language |
English |
description |
ABSTRACT Reconstructions of former ice masses from glacial geomorphology help to constrain the nature and timing of glaciation in relation to climatic forcing. This paper presents a new reconstruction of the glacial history of five ice lobes in southernmost South America: the Bahía Inútil − San Sebastián, Magellan, Otway, Skyring and Río Gallegos ice lobes. We use previous geomorphological mapping of glacial landforms to reconstruct former glacial limits and proglacial lakes, demarcate flow‐sets from the distribution of glacial lineations, and evaluate glacial landsystem signatures and their palaeoglaciological implications. Evidence suggests that the ice lobes predominantly reflect active temperate glacial landsystems, which may have switched to polythermal systems when periods of cold‐based ice developed ephemerally. This complex landsystem signature implies that the ice lobes were sensitive to regional climate variability, with active re‐advances during overall retreat of the ice margins. There is also evidence for periods of fast ice flow and possible surge‐like activity in the region, followed by the rapid retreat or even collapse of some of the ice lobes in association with proglacial lakes. Constraining our new reconstruction with published chronological information suggests that at least some of the ice lobes advanced before the global Last Glacial Maximum (gLGM: ca. 26.5–19 ka) during the last glacial cycle. Our new reconstruction demonstrates a more complex picture of ice dynamics than has previously been portrayed, and one in which the advance and retreat of the ice lobes was likely to have been primarily driven by changes in climate. As such, ice advances before the gLGM in the southernmost part of the Patagonian Ice Sheet are likely to indicate a wider climatic forcing at this time. |
author2 |
Explorers Club Natural Resources Wales Durham University |
format |
Article in Journal/Newspaper |
author |
Darvill, Christopher M. Stokes, Chris R. Bentley, Michael J. Evans, David J. A. Lovell, Harold |
spellingShingle |
Darvill, Christopher M. Stokes, Chris R. Bentley, Michael J. Evans, David J. A. Lovell, Harold Dynamics of former ice lobes of the southernmost Patagonian Ice Sheet based on a glacial landsystems approach |
author_facet |
Darvill, Christopher M. Stokes, Chris R. Bentley, Michael J. Evans, David J. A. Lovell, Harold |
author_sort |
Darvill, Christopher M. |
title |
Dynamics of former ice lobes of the southernmost Patagonian Ice Sheet based on a glacial landsystems approach |
title_short |
Dynamics of former ice lobes of the southernmost Patagonian Ice Sheet based on a glacial landsystems approach |
title_full |
Dynamics of former ice lobes of the southernmost Patagonian Ice Sheet based on a glacial landsystems approach |
title_fullStr |
Dynamics of former ice lobes of the southernmost Patagonian Ice Sheet based on a glacial landsystems approach |
title_full_unstemmed |
Dynamics of former ice lobes of the southernmost Patagonian Ice Sheet based on a glacial landsystems approach |
title_sort |
dynamics of former ice lobes of the southernmost patagonian ice sheet based on a glacial landsystems approach |
publisher |
Wiley |
publishDate |
2016 |
url |
http://dx.doi.org/10.1002/jqs.2890 https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1002%2Fjqs.2890 https://onlinelibrary.wiley.com/doi/pdf/10.1002/jqs.2890 |
long_lat |
ENVELOPE(-67.150,-67.150,-68.133,-68.133) ENVELOPE(-60.783,-60.783,-64.050,-64.050) ENVELOPE(-62.917,-62.917,-64.883,-64.883) |
geographic |
Gallegos Inútil bahía Inútil |
geographic_facet |
Gallegos Inútil bahía Inútil |
genre |
Ice Sheet |
genre_facet |
Ice Sheet |
op_source |
Journal of Quaternary Science volume 32, issue 6, page 857-876 ISSN 0267-8179 1099-1417 |
op_rights |
http://creativecommons.org/licenses/by/4.0/ |
op_doi |
https://doi.org/10.1002/jqs.2890 |
container_title |
Journal of Quaternary Science |
container_volume |
32 |
container_issue |
6 |
container_start_page |
857 |
op_container_end_page |
876 |
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1811639659624660992 |