Characterization of subglacial marginal channels using 3-D analysis of high-density ground-penetrating radar data
Abstract Studying subglacial drainage networks is important for understanding the potential relationship between channel dynamics and rapid glacier recession as well as the role of subglacial channels in subglacial sediment evacuation. In order to delineate the planform geometry of snout marginal su...
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Language: | English |
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Cambridge University Press (CUP)
2021
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Online Access: | http://dx.doi.org/10.1017/jog.2021.26 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143021000265 |
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crcambridgeupr:10.1017/jog.2021.26 2024-09-09T19:49:01+00:00 Characterization of subglacial marginal channels using 3-D analysis of high-density ground-penetrating radar data Egli, Pascal E. Irving, James Lane, Stuart N. 2021 http://dx.doi.org/10.1017/jog.2021.26 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143021000265 en eng Cambridge University Press (CUP) http://creativecommons.org/licenses/by/4.0/ Journal of Glaciology volume 67, issue 264, page 759-772 ISSN 0022-1430 1727-5652 journal-article 2021 crcambridgeupr https://doi.org/10.1017/jog.2021.26 2024-08-07T04:04:22Z Abstract Studying subglacial drainage networks is important for understanding the potential relationship between channel dynamics and rapid glacier recession as well as the role of subglacial channels in subglacial sediment evacuation. In order to delineate the planform geometry of snout marginal subglacial channels, densely spaced ground-penetrating radar (GPR) measurements at a frequency of ~70 MHz were carried out over the snout marginal zones of two temperate glaciers in the southwestern Swiss Alps, the Haut Glacier d'Arolla and the Glacier d'Otemma. Three-dimensional (3-D) data processing and amplitude analysis of the GPR reflection along the glacier bed was used to map the channels. At the Haut Glacier d'Arolla, two relatively straight channels of several meters in width were identified. The positions of these channels correspond well with the locations of channel outlets at the glacier terminus, as well as with fractures appearing on the glacier surface one month after the GPR data acquisition. The latter are believed to represent the beginning of ice collapse above the subglacial channels. At the Glacier d'Otemma, a major subglacial conduit was detected with similar dimensions to those identified at the Haut Glacier d'Arolla, but greater sinuosity. The position of this channel was confirmed by drone-based imagery acquired after glacier margin collapse. Our results confirm that high-density 3-D GPR surveys can be used to map subglacial channels near temperate alpine glacier margins. Article in Journal/Newspaper Journal of Glaciology Cambridge University Press Journal of Glaciology 67 264 759 772 |
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Open Polar |
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Cambridge University Press |
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crcambridgeupr |
language |
English |
description |
Abstract Studying subglacial drainage networks is important for understanding the potential relationship between channel dynamics and rapid glacier recession as well as the role of subglacial channels in subglacial sediment evacuation. In order to delineate the planform geometry of snout marginal subglacial channels, densely spaced ground-penetrating radar (GPR) measurements at a frequency of ~70 MHz were carried out over the snout marginal zones of two temperate glaciers in the southwestern Swiss Alps, the Haut Glacier d'Arolla and the Glacier d'Otemma. Three-dimensional (3-D) data processing and amplitude analysis of the GPR reflection along the glacier bed was used to map the channels. At the Haut Glacier d'Arolla, two relatively straight channels of several meters in width were identified. The positions of these channels correspond well with the locations of channel outlets at the glacier terminus, as well as with fractures appearing on the glacier surface one month after the GPR data acquisition. The latter are believed to represent the beginning of ice collapse above the subglacial channels. At the Glacier d'Otemma, a major subglacial conduit was detected with similar dimensions to those identified at the Haut Glacier d'Arolla, but greater sinuosity. The position of this channel was confirmed by drone-based imagery acquired after glacier margin collapse. Our results confirm that high-density 3-D GPR surveys can be used to map subglacial channels near temperate alpine glacier margins. |
format |
Article in Journal/Newspaper |
author |
Egli, Pascal E. Irving, James Lane, Stuart N. |
spellingShingle |
Egli, Pascal E. Irving, James Lane, Stuart N. Characterization of subglacial marginal channels using 3-D analysis of high-density ground-penetrating radar data |
author_facet |
Egli, Pascal E. Irving, James Lane, Stuart N. |
author_sort |
Egli, Pascal E. |
title |
Characterization of subglacial marginal channels using 3-D analysis of high-density ground-penetrating radar data |
title_short |
Characterization of subglacial marginal channels using 3-D analysis of high-density ground-penetrating radar data |
title_full |
Characterization of subglacial marginal channels using 3-D analysis of high-density ground-penetrating radar data |
title_fullStr |
Characterization of subglacial marginal channels using 3-D analysis of high-density ground-penetrating radar data |
title_full_unstemmed |
Characterization of subglacial marginal channels using 3-D analysis of high-density ground-penetrating radar data |
title_sort |
characterization of subglacial marginal channels using 3-d analysis of high-density ground-penetrating radar data |
publisher |
Cambridge University Press (CUP) |
publishDate |
2021 |
url |
http://dx.doi.org/10.1017/jog.2021.26 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143021000265 |
genre |
Journal of Glaciology |
genre_facet |
Journal of Glaciology |
op_source |
Journal of Glaciology volume 67, issue 264, page 759-772 ISSN 0022-1430 1727-5652 |
op_rights |
http://creativecommons.org/licenses/by/4.0/ |
op_doi |
https://doi.org/10.1017/jog.2021.26 |
container_title |
Journal of Glaciology |
container_volume |
67 |
container_issue |
264 |
container_start_page |
759 |
op_container_end_page |
772 |
_version_ |
1809918373109170176 |