Anatomy of terminal moraine segments and implied lake stability on Ngozumpa Glacier, Nepal, from electrical resistivity tomography (ERT)
Moraine-dammed lakes at debris-covered glaciers are becoming increasingly common and pose significant outburst flood hazards if the dam is breached. While moraine subsurface structure and internal processes are likely to influence dam stability, only few sites have so far been investigated. We condu...
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Online Access: | https://risweb.st-andrews.ac.uk/portal/en/researchoutput/anatomy-of-terminal-moraine-segments-and-implied-lake-stability-on-ngozumpa-glacier-nepal-from-electrical-resistivity-tomography-ert(14c864ac-c758-4a37-9ad6-54b1609e811f).html https://doi.org/10.1038/srep46766 https://research-repository.st-andrews.ac.uk/bitstream/10023/12433/1/Thompson_2017_SR_TerminalMoraineSegments_CC.pdf |
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ftunstandrewcris:oai:risweb.st-andrews.ac.uk:publications/14c864ac-c758-4a37-9ad6-54b1609e811f 2023-05-15T16:39:10+02:00 Anatomy of terminal moraine segments and implied lake stability on Ngozumpa Glacier, Nepal, from electrical resistivity tomography (ERT) Thompson, Sarah S. Kulessa, Bernd Benn, Douglas I. Mertes, Jordan R. 2017-04-20 application/pdf https://risweb.st-andrews.ac.uk/portal/en/researchoutput/anatomy-of-terminal-moraine-segments-and-implied-lake-stability-on-ngozumpa-glacier-nepal-from-electrical-resistivity-tomography-ert(14c864ac-c758-4a37-9ad6-54b1609e811f).html https://doi.org/10.1038/srep46766 https://research-repository.st-andrews.ac.uk/bitstream/10023/12433/1/Thompson_2017_SR_TerminalMoraineSegments_CC.pdf eng eng info:eu-repo/semantics/openAccess Thompson , S S , Kulessa , B , Benn , D I & Mertes , J R 2017 , ' Anatomy of terminal moraine segments and implied lake stability on Ngozumpa Glacier, Nepal, from electrical resistivity tomography (ERT) ' , Scientific Reports , vol. 7 , 46766 . https://doi.org/10.1038/srep46766 article 2017 ftunstandrewcris https://doi.org/10.1038/srep46766 2022-06-02T07:48:09Z Moraine-dammed lakes at debris-covered glaciers are becoming increasingly common and pose significant outburst flood hazards if the dam is breached. While moraine subsurface structure and internal processes are likely to influence dam stability, only few sites have so far been investigated. We conducted electrical resistivity tomography (ERT) surveys at two sites on the terminal moraine complex of the Ngozumpa Glacier, Nepal, to aid assessment of future terminus stability. The resistivity signature of glacier ice at the site (100-15 kΩ m) is more consistent with values measured from cold glacier ice and while this may be feasible, uncertainties in the data inversion introduce ambiguity to this thermal interpretation. However, the ERT data does provide a significant improvement to our knowledge of the subsurface characteristics at these sites, clearly showing the presence (or absence) of glacier ice. Our interpretation is that of a highly complex latero-terminal moraine, resulting from interaction between previous glacier advance, recession and outburst flooding. If the base-level Spillway Lake continues to expand to a fully formed moraine-dammed glacial lake, the degradation of the ice core could have implications for glacial lake outburst risk. Article in Journal/Newspaper ice core University of St Andrews: Research Portal Glacial Lake ENVELOPE(-129.463,-129.463,58.259,58.259) Scientific Reports 7 1 |
institution |
Open Polar |
collection |
University of St Andrews: Research Portal |
op_collection_id |
ftunstandrewcris |
language |
English |
description |
Moraine-dammed lakes at debris-covered glaciers are becoming increasingly common and pose significant outburst flood hazards if the dam is breached. While moraine subsurface structure and internal processes are likely to influence dam stability, only few sites have so far been investigated. We conducted electrical resistivity tomography (ERT) surveys at two sites on the terminal moraine complex of the Ngozumpa Glacier, Nepal, to aid assessment of future terminus stability. The resistivity signature of glacier ice at the site (100-15 kΩ m) is more consistent with values measured from cold glacier ice and while this may be feasible, uncertainties in the data inversion introduce ambiguity to this thermal interpretation. However, the ERT data does provide a significant improvement to our knowledge of the subsurface characteristics at these sites, clearly showing the presence (or absence) of glacier ice. Our interpretation is that of a highly complex latero-terminal moraine, resulting from interaction between previous glacier advance, recession and outburst flooding. If the base-level Spillway Lake continues to expand to a fully formed moraine-dammed glacial lake, the degradation of the ice core could have implications for glacial lake outburst risk. |
format |
Article in Journal/Newspaper |
author |
Thompson, Sarah S. Kulessa, Bernd Benn, Douglas I. Mertes, Jordan R. |
spellingShingle |
Thompson, Sarah S. Kulessa, Bernd Benn, Douglas I. Mertes, Jordan R. Anatomy of terminal moraine segments and implied lake stability on Ngozumpa Glacier, Nepal, from electrical resistivity tomography (ERT) |
author_facet |
Thompson, Sarah S. Kulessa, Bernd Benn, Douglas I. Mertes, Jordan R. |
author_sort |
Thompson, Sarah S. |
title |
Anatomy of terminal moraine segments and implied lake stability on Ngozumpa Glacier, Nepal, from electrical resistivity tomography (ERT) |
title_short |
Anatomy of terminal moraine segments and implied lake stability on Ngozumpa Glacier, Nepal, from electrical resistivity tomography (ERT) |
title_full |
Anatomy of terminal moraine segments and implied lake stability on Ngozumpa Glacier, Nepal, from electrical resistivity tomography (ERT) |
title_fullStr |
Anatomy of terminal moraine segments and implied lake stability on Ngozumpa Glacier, Nepal, from electrical resistivity tomography (ERT) |
title_full_unstemmed |
Anatomy of terminal moraine segments and implied lake stability on Ngozumpa Glacier, Nepal, from electrical resistivity tomography (ERT) |
title_sort |
anatomy of terminal moraine segments and implied lake stability on ngozumpa glacier, nepal, from electrical resistivity tomography (ert) |
publishDate |
2017 |
url |
https://risweb.st-andrews.ac.uk/portal/en/researchoutput/anatomy-of-terminal-moraine-segments-and-implied-lake-stability-on-ngozumpa-glacier-nepal-from-electrical-resistivity-tomography-ert(14c864ac-c758-4a37-9ad6-54b1609e811f).html https://doi.org/10.1038/srep46766 https://research-repository.st-andrews.ac.uk/bitstream/10023/12433/1/Thompson_2017_SR_TerminalMoraineSegments_CC.pdf |
long_lat |
ENVELOPE(-129.463,-129.463,58.259,58.259) |
geographic |
Glacial Lake |
geographic_facet |
Glacial Lake |
genre |
ice core |
genre_facet |
ice core |
op_source |
Thompson , S S , Kulessa , B , Benn , D I & Mertes , J R 2017 , ' Anatomy of terminal moraine segments and implied lake stability on Ngozumpa Glacier, Nepal, from electrical resistivity tomography (ERT) ' , Scientific Reports , vol. 7 , 46766 . https://doi.org/10.1038/srep46766 |
op_rights |
info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.1038/srep46766 |
container_title |
Scientific Reports |
container_volume |
7 |
container_issue |
1 |
_version_ |
1766029493734998016 |