Evidence for rapid ice flow and proglacial lake evolution around the central Strait of Magellan region, southernmost Patagonia
Abstract This paper presents a detailed palaeoglaciological reconstruction of ice sheet dynamics in the Seno Skyring, Seno Otway and Strait of Magellan region of the former Patagonian Ice Sheet, with a particular focus on previously hypothesised zones of rapid ice flow and the evolution of proglacia...
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crwiley:10.1002/jqs.2555 2024-06-02T08:08:16+00:00 Evidence for rapid ice flow and proglacial lake evolution around the central Strait of Magellan region, southernmost Patagonia Lovell, Harold Stokes, Chris R. Bentley, Michael J. Benn, Douglas I. 2012 http://dx.doi.org/10.1002/jqs.2555 https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1002%2Fjqs.2555 https://onlinelibrary.wiley.com/doi/pdf/10.1002/jqs.2555 en eng Wiley http://onlinelibrary.wiley.com/termsAndConditions#vor Journal of Quaternary Science volume 27, issue 6, page 625-638 ISSN 0267-8179 1099-1417 journal-article 2012 crwiley https://doi.org/10.1002/jqs.2555 2024-05-03T11:48:52Z Abstract This paper presents a detailed palaeoglaciological reconstruction of ice sheet dynamics in the Seno Skyring, Seno Otway and Strait of Magellan region of the former Patagonian Ice Sheet, with a particular focus on previously hypothesised zones of rapid ice flow and the evolution of proglacial lakes. Geomorphological mapping from a combination of satellite imagery and oblique and vertical aerial photographs reveals a variety of glacial landforms that are grouped into several discrete flow‐sets and associated ice margin positions. The most distinct features are represented by flow‐sets of highly elongate streamlined glacial lineations on both sides of the Strait of Magellan. Based on the shape and dimensions of the flow‐sets and their abrupt lateral margins, a transverse and longitudinal variation in glacial lineation length and elongation ratio, and the reported presence of a potentially deformable bed and thrust moraines, the flow‐sets are interpreted as zones of rapid ice flow within the Otway and Magellan lobes. We hypothesise that this provides evidence for contemporaneous surge‐like advances within the lobes, which may explain the asymmetry in the lobate margin positions on either side of the strait. The mechanisms that initiated rapid flow are unclear, but are likely to have been influenced by internal factors such as a change in thermal/hydrological conditions at the bed. The topography of the region suggests ice‐dammed lakes would have formed as the ice lobes retreated. The westernmost of the former lakes, Lake Skyring, is delimited by a series of palaeo‐shorelines surrounding the present‐day lake Laguna Blanca and we reconstruct lake evolution based on manipulation of a digital elevation model. The size and orientation of meltwater channels and a large outwash plain indicate that Lake Skyring drained eastwards towards the Strait of Magellan, probably quite rapidly. We conclude that the potential for quasi‐independent surge‐like behaviour within adjacent lobes raises the possibility that, during ... Article in Journal/Newspaper Ice Sheet Wiley Online Library Patagonia Journal of Quaternary Science 27 6 625 638 |
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Open Polar |
collection |
Wiley Online Library |
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crwiley |
language |
English |
description |
Abstract This paper presents a detailed palaeoglaciological reconstruction of ice sheet dynamics in the Seno Skyring, Seno Otway and Strait of Magellan region of the former Patagonian Ice Sheet, with a particular focus on previously hypothesised zones of rapid ice flow and the evolution of proglacial lakes. Geomorphological mapping from a combination of satellite imagery and oblique and vertical aerial photographs reveals a variety of glacial landforms that are grouped into several discrete flow‐sets and associated ice margin positions. The most distinct features are represented by flow‐sets of highly elongate streamlined glacial lineations on both sides of the Strait of Magellan. Based on the shape and dimensions of the flow‐sets and their abrupt lateral margins, a transverse and longitudinal variation in glacial lineation length and elongation ratio, and the reported presence of a potentially deformable bed and thrust moraines, the flow‐sets are interpreted as zones of rapid ice flow within the Otway and Magellan lobes. We hypothesise that this provides evidence for contemporaneous surge‐like advances within the lobes, which may explain the asymmetry in the lobate margin positions on either side of the strait. The mechanisms that initiated rapid flow are unclear, but are likely to have been influenced by internal factors such as a change in thermal/hydrological conditions at the bed. The topography of the region suggests ice‐dammed lakes would have formed as the ice lobes retreated. The westernmost of the former lakes, Lake Skyring, is delimited by a series of palaeo‐shorelines surrounding the present‐day lake Laguna Blanca and we reconstruct lake evolution based on manipulation of a digital elevation model. The size and orientation of meltwater channels and a large outwash plain indicate that Lake Skyring drained eastwards towards the Strait of Magellan, probably quite rapidly. We conclude that the potential for quasi‐independent surge‐like behaviour within adjacent lobes raises the possibility that, during ... |
format |
Article in Journal/Newspaper |
author |
Lovell, Harold Stokes, Chris R. Bentley, Michael J. Benn, Douglas I. |
spellingShingle |
Lovell, Harold Stokes, Chris R. Bentley, Michael J. Benn, Douglas I. Evidence for rapid ice flow and proglacial lake evolution around the central Strait of Magellan region, southernmost Patagonia |
author_facet |
Lovell, Harold Stokes, Chris R. Bentley, Michael J. Benn, Douglas I. |
author_sort |
Lovell, Harold |
title |
Evidence for rapid ice flow and proglacial lake evolution around the central Strait of Magellan region, southernmost Patagonia |
title_short |
Evidence for rapid ice flow and proglacial lake evolution around the central Strait of Magellan region, southernmost Patagonia |
title_full |
Evidence for rapid ice flow and proglacial lake evolution around the central Strait of Magellan region, southernmost Patagonia |
title_fullStr |
Evidence for rapid ice flow and proglacial lake evolution around the central Strait of Magellan region, southernmost Patagonia |
title_full_unstemmed |
Evidence for rapid ice flow and proglacial lake evolution around the central Strait of Magellan region, southernmost Patagonia |
title_sort |
evidence for rapid ice flow and proglacial lake evolution around the central strait of magellan region, southernmost patagonia |
publisher |
Wiley |
publishDate |
2012 |
url |
http://dx.doi.org/10.1002/jqs.2555 https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1002%2Fjqs.2555 https://onlinelibrary.wiley.com/doi/pdf/10.1002/jqs.2555 |
geographic |
Patagonia |
geographic_facet |
Patagonia |
genre |
Ice Sheet |
genre_facet |
Ice Sheet |
op_source |
Journal of Quaternary Science volume 27, issue 6, page 625-638 ISSN 0267-8179 1099-1417 |
op_rights |
http://onlinelibrary.wiley.com/termsAndConditions#vor |
op_doi |
https://doi.org/10.1002/jqs.2555 |
container_title |
Journal of Quaternary Science |
container_volume |
27 |
container_issue |
6 |
container_start_page |
625 |
op_container_end_page |
638 |
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1800753470237573120 |