Basal seismicity of the Northeast Greenland Ice Stream
Seismic studies of glaciers yield insights into spatio-temporal processes within and beneath glaciers on scales relevant to flow and deformation of the ice. These methods enable direct monitoring of the bed in ways that complement other geophysical techniques, such as geodetic or ground penetrating...
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Cambridge University Press
2020
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Online Access: | https://doi.org/10.1017/jog.2020.17 https://doaj.org/article/0b06d9349dac4191b6c7c6dd6f981527 |
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ftdoajarticles:oai:doaj.org/article:0b06d9349dac4191b6c7c6dd6f981527 2023-05-15T15:05:56+02:00 Basal seismicity of the Northeast Greenland Ice Stream Ian W. McBrearty Lucas K. Zoet Sridhar Anandakrishnan 2020-06-01T00:00:00Z https://doi.org/10.1017/jog.2020.17 https://doaj.org/article/0b06d9349dac4191b6c7c6dd6f981527 EN eng Cambridge University Press https://www.cambridge.org/core/product/identifier/S0022143020000179/type/journal_article https://doaj.org/toc/0022-1430 https://doaj.org/toc/1727-5652 doi:10.1017/jog.2020.17 0022-1430 1727-5652 https://doaj.org/article/0b06d9349dac4191b6c7c6dd6f981527 Journal of Glaciology, Vol 66, Pp 430-446 (2020) Seismology arctic glaciology glacier mechanics Environmental sciences GE1-350 Meteorology. Climatology QC851-999 article 2020 ftdoajarticles https://doi.org/10.1017/jog.2020.17 2023-03-12T01:30:57Z Seismic studies of glaciers yield insights into spatio-temporal processes within and beneath glaciers on scales relevant to flow and deformation of the ice. These methods enable direct monitoring of the bed in ways that complement other geophysical techniques, such as geodetic or ground penetrating radar observations. In this work, we report on the analysis of passive seismic data collected from the interior of the North East Greenland Ice Stream, the Greenland ice sheet's largest outlet glacier. We record thousands of basal earthquakes, many of which repeat with nearly identical waveforms. We also record many long-duration glacial tremor episodes that migrate across the seismic network with slow velocities (e.g. ~4ā12 m sā1). Analysis of the basal earthquakes indicates a transition between times of individual event activity and times of tremor activity. We suggest that both processes are produced by shear slip at localized asperities along the bed. The transition between discrete and quasi-continuous slipping modes may be driven by pore-water pressure transients or heterogeneous strain accumulation in the ice due to strength contrasts of the underlying till. Article in Journal/Newspaper Arctic East Greenland glacier Greenland Journal of Glaciology Directory of Open Access Journals: DOAJ Articles Arctic Greenland Journal of Glaciology 66 257 430 446 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
Seismology arctic glaciology glacier mechanics Environmental sciences GE1-350 Meteorology. Climatology QC851-999 |
spellingShingle |
Seismology arctic glaciology glacier mechanics Environmental sciences GE1-350 Meteorology. Climatology QC851-999 Ian W. McBrearty Lucas K. Zoet Sridhar Anandakrishnan Basal seismicity of the Northeast Greenland Ice Stream |
topic_facet |
Seismology arctic glaciology glacier mechanics Environmental sciences GE1-350 Meteorology. Climatology QC851-999 |
description |
Seismic studies of glaciers yield insights into spatio-temporal processes within and beneath glaciers on scales relevant to flow and deformation of the ice. These methods enable direct monitoring of the bed in ways that complement other geophysical techniques, such as geodetic or ground penetrating radar observations. In this work, we report on the analysis of passive seismic data collected from the interior of the North East Greenland Ice Stream, the Greenland ice sheet's largest outlet glacier. We record thousands of basal earthquakes, many of which repeat with nearly identical waveforms. We also record many long-duration glacial tremor episodes that migrate across the seismic network with slow velocities (e.g. ~4ā12 m sā1). Analysis of the basal earthquakes indicates a transition between times of individual event activity and times of tremor activity. We suggest that both processes are produced by shear slip at localized asperities along the bed. The transition between discrete and quasi-continuous slipping modes may be driven by pore-water pressure transients or heterogeneous strain accumulation in the ice due to strength contrasts of the underlying till. |
format |
Article in Journal/Newspaper |
author |
Ian W. McBrearty Lucas K. Zoet Sridhar Anandakrishnan |
author_facet |
Ian W. McBrearty Lucas K. Zoet Sridhar Anandakrishnan |
author_sort |
Ian W. McBrearty |
title |
Basal seismicity of the Northeast Greenland Ice Stream |
title_short |
Basal seismicity of the Northeast Greenland Ice Stream |
title_full |
Basal seismicity of the Northeast Greenland Ice Stream |
title_fullStr |
Basal seismicity of the Northeast Greenland Ice Stream |
title_full_unstemmed |
Basal seismicity of the Northeast Greenland Ice Stream |
title_sort |
basal seismicity of the northeast greenland ice stream |
publisher |
Cambridge University Press |
publishDate |
2020 |
url |
https://doi.org/10.1017/jog.2020.17 https://doaj.org/article/0b06d9349dac4191b6c7c6dd6f981527 |
geographic |
Arctic Greenland |
geographic_facet |
Arctic Greenland |
genre |
Arctic East Greenland glacier Greenland Journal of Glaciology |
genre_facet |
Arctic East Greenland glacier Greenland Journal of Glaciology |
op_source |
Journal of Glaciology, Vol 66, Pp 430-446 (2020) |
op_relation |
https://www.cambridge.org/core/product/identifier/S0022143020000179/type/journal_article https://doaj.org/toc/0022-1430 https://doaj.org/toc/1727-5652 doi:10.1017/jog.2020.17 0022-1430 1727-5652 https://doaj.org/article/0b06d9349dac4191b6c7c6dd6f981527 |
op_doi |
https://doi.org/10.1017/jog.2020.17 |
container_title |
Journal of Glaciology |
container_volume |
66 |
container_issue |
257 |
container_start_page |
430 |
op_container_end_page |
446 |
_version_ |
1766337622090711040 |