Icequake source mechanisms for studying glacial sliding
Improving our understanding of glacial sliding is crucial for constraining basal drag in ice dynamics models. We use icequakes, sudden releases of seismic energy as the ice slides over the bed, to provide geophysical observations that can be used to aid understanding of the physics of glacial slidin...
Published in: | Journal of Geophysical Research: Earth Surface |
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Format: | Article in Journal/Newspaper |
Language: | English |
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Wiley for AGU
2019
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Online Access: | http://eprints.esc.cam.ac.uk/4434/ http://eprints.esc.cam.ac.uk/4434/1/Icequake_source_mechanisms_for_studying_glacial_sliding_draft.pdf http://eprints.esc.cam.ac.uk/4434/3/2020JF005627.pdf http://eprints.esc.cam.ac.uk/4434/4/jgrf21271-sup-0001-2020jf005627-si.pdf https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2020JF005627 https://doi.org/10.1029/2020JF005627 |
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ftucambridgeesc:oai:eprints.esc.cam.ac.uk:4434 2023-05-15T13:55:45+02:00 Icequake source mechanisms for studying glacial sliding Hudson, Thomas S. Brisbourne, Alex M. Walter, F. Graff, D. White, R. S. Smith, A. M. 2019-03-26 text http://eprints.esc.cam.ac.uk/4434/ http://eprints.esc.cam.ac.uk/4434/1/Icequake_source_mechanisms_for_studying_glacial_sliding_draft.pdf http://eprints.esc.cam.ac.uk/4434/3/2020JF005627.pdf http://eprints.esc.cam.ac.uk/4434/4/jgrf21271-sup-0001-2020jf005627-si.pdf https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2020JF005627 https://doi.org/10.1029/2020JF005627 en eng Wiley for AGU http://eprints.esc.cam.ac.uk/4434/1/Icequake_source_mechanisms_for_studying_glacial_sliding_draft.pdf http://eprints.esc.cam.ac.uk/4434/3/2020JF005627.pdf http://eprints.esc.cam.ac.uk/4434/4/jgrf21271-sup-0001-2020jf005627-si.pdf Hudson, Thomas S. and Brisbourne, Alex M. and Walter, F. and Graff, D. and White, R. S. and Smith, A. M. (2019) Icequake source mechanisms for studying glacial sliding. Journal of Geophysical Research-Earth Surface, 125 (11). ISSN 2169-9011 DOI https://doi.org/10.1029/2020JF005627 <https://doi.org/10.1029/2020JF005627> cc_by CC-BY 02 - Geodynamics Geophysics and Tectonics Article PeerReviewed 2019 ftucambridgeesc https://doi.org/10.1029/2020JF005627 2021-03-11T23:16:38Z Improving our understanding of glacial sliding is crucial for constraining basal drag in ice dynamics models. We use icequakes, sudden releases of seismic energy as the ice slides over the bed, to provide geophysical observations that can be used to aid understanding of the physics of glacial sliding and constrain ice dynamics models. These icequakes are located at the bed of an alpine glacier in Switzerland and the Rutford Ice Stream, West Antarctica, two extremes of glacial settings and spatial scales. We investigate a number of possible icequake source mechanisms by performing full waveform inversions to constrain the fundamental physics and stress release during an icequake stick-slip event. Results show that double-couple mechanisms best describe the source for the events from both glacial settings and the icequakes originate at or very near the ice-bed interface. We also present an exploratory method for attempting to measure the till shear modulus, if indirect reflected icequake radiation is observed. The results of this study increase our understanding of how icequakes are associated with basal drag while also providing the foundation for a method of remotely measuring bed shear strength Article in Journal/Newspaper Antarc* Antarctica Rutford Ice Stream West Antarctica University of Cambridge, Department of Earth Sciences: ESC Publications Rutford ENVELOPE(-85.300,-85.300,-78.600,-78.600) Rutford Ice Stream ENVELOPE(-80.000,-80.000,-79.167,-79.167) West Antarctica Journal of Geophysical Research: Earth Surface 125 11 |
institution |
Open Polar |
collection |
University of Cambridge, Department of Earth Sciences: ESC Publications |
op_collection_id |
ftucambridgeesc |
language |
English |
topic |
02 - Geodynamics Geophysics and Tectonics |
spellingShingle |
02 - Geodynamics Geophysics and Tectonics Hudson, Thomas S. Brisbourne, Alex M. Walter, F. Graff, D. White, R. S. Smith, A. M. Icequake source mechanisms for studying glacial sliding |
topic_facet |
02 - Geodynamics Geophysics and Tectonics |
description |
Improving our understanding of glacial sliding is crucial for constraining basal drag in ice dynamics models. We use icequakes, sudden releases of seismic energy as the ice slides over the bed, to provide geophysical observations that can be used to aid understanding of the physics of glacial sliding and constrain ice dynamics models. These icequakes are located at the bed of an alpine glacier in Switzerland and the Rutford Ice Stream, West Antarctica, two extremes of glacial settings and spatial scales. We investigate a number of possible icequake source mechanisms by performing full waveform inversions to constrain the fundamental physics and stress release during an icequake stick-slip event. Results show that double-couple mechanisms best describe the source for the events from both glacial settings and the icequakes originate at or very near the ice-bed interface. We also present an exploratory method for attempting to measure the till shear modulus, if indirect reflected icequake radiation is observed. The results of this study increase our understanding of how icequakes are associated with basal drag while also providing the foundation for a method of remotely measuring bed shear strength |
format |
Article in Journal/Newspaper |
author |
Hudson, Thomas S. Brisbourne, Alex M. Walter, F. Graff, D. White, R. S. Smith, A. M. |
author_facet |
Hudson, Thomas S. Brisbourne, Alex M. Walter, F. Graff, D. White, R. S. Smith, A. M. |
author_sort |
Hudson, Thomas S. |
title |
Icequake source mechanisms for studying glacial sliding |
title_short |
Icequake source mechanisms for studying glacial sliding |
title_full |
Icequake source mechanisms for studying glacial sliding |
title_fullStr |
Icequake source mechanisms for studying glacial sliding |
title_full_unstemmed |
Icequake source mechanisms for studying glacial sliding |
title_sort |
icequake source mechanisms for studying glacial sliding |
publisher |
Wiley for AGU |
publishDate |
2019 |
url |
http://eprints.esc.cam.ac.uk/4434/ http://eprints.esc.cam.ac.uk/4434/1/Icequake_source_mechanisms_for_studying_glacial_sliding_draft.pdf http://eprints.esc.cam.ac.uk/4434/3/2020JF005627.pdf http://eprints.esc.cam.ac.uk/4434/4/jgrf21271-sup-0001-2020jf005627-si.pdf https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2020JF005627 https://doi.org/10.1029/2020JF005627 |
long_lat |
ENVELOPE(-85.300,-85.300,-78.600,-78.600) ENVELOPE(-80.000,-80.000,-79.167,-79.167) |
geographic |
Rutford Rutford Ice Stream West Antarctica |
geographic_facet |
Rutford Rutford Ice Stream West Antarctica |
genre |
Antarc* Antarctica Rutford Ice Stream West Antarctica |
genre_facet |
Antarc* Antarctica Rutford Ice Stream West Antarctica |
op_relation |
http://eprints.esc.cam.ac.uk/4434/1/Icequake_source_mechanisms_for_studying_glacial_sliding_draft.pdf http://eprints.esc.cam.ac.uk/4434/3/2020JF005627.pdf http://eprints.esc.cam.ac.uk/4434/4/jgrf21271-sup-0001-2020jf005627-si.pdf Hudson, Thomas S. and Brisbourne, Alex M. and Walter, F. and Graff, D. and White, R. S. and Smith, A. M. (2019) Icequake source mechanisms for studying glacial sliding. Journal of Geophysical Research-Earth Surface, 125 (11). ISSN 2169-9011 DOI https://doi.org/10.1029/2020JF005627 <https://doi.org/10.1029/2020JF005627> |
op_rights |
cc_by |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.1029/2020JF005627 |
container_title |
Journal of Geophysical Research: Earth Surface |
container_volume |
125 |
container_issue |
11 |
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1766262582423846912 |