Capturing Glacier-Wide Cryoseismicity With Distributed Acoustic Sensing
Over the past 1-2 decades, seismological measurements have provided new and unique insights into glacier and ice sheet dynamics. At the same time, sensor coverage is typically limited in harsh glacial environments with littile or no access. Turning kilometer-long fiber optic cables placed on the Ear...
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ftethz:oai:www.research-collection.ethz.ch:20.500.11850/526299 2023-05-15T13:53:55+02:00 Capturing Glacier-Wide Cryoseismicity With Distributed Acoustic Sensing Walter, Fabian Thomas Paitz, Patrick Fichtner, Andreas Edme, Pascal Gajek, Wojciech Lipovsky, Bradley P. Martin, Eileen 2021 application/application/pdf https://hdl.handle.net/20.500.11850/526299 https://doi.org/10.3929/ethz-b-000526299 en eng Copernicus info:eu-repo/semantics/altIdentifier/doi/10.5194/egusphere-egu21-5809 http://hdl.handle.net/20.500.11850/526299 doi:10.3929/ethz-b-000526299 info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/4.0/ Creative Commons Attribution 4.0 International CC-BY EGUsphere info:eu-repo/semantics/conferenceObject info:eu-repo/semantics/publishedVersion 2021 ftethz https://doi.org/20.500.11850/526299 https://doi.org/10.3929/ethz-b-000526299 https://doi.org/10.5194/egusphere-egu21-5809 2022-04-25T14:42:45Z Over the past 1-2 decades, seismological measurements have provided new and unique insights into glacier and ice sheet dynamics. At the same time, sensor coverage is typically limited in harsh glacial environments with littile or no access. Turning kilometer-long fiber optic cables placed on the Earth’s surface into thousands of seismic sensors, Distributed Acoustic Sensing (DAS) may overcome the limitation of sensor coverage in the cryosphere. First DAS applications on the Greenland and Antarctic ice sheets and on Alpine glacier ice have highlighted the technique’s superiority. Signals of natural and man-made seismic sources can be resolved with an unrivaled level of detail. This offers glaciologists new perspectives to interpret their seismograms in terms of ice structure, basal boundary conditions and source locations. However, previous studies employed only relatively small network scales with a point-like borehole deployment or < 1 km cable aperture at the ice surface. Here we present a DAS installation, which aims to cover the majority of an Alpine glacier catchment: For one month in summer 2020 we deployed a 9 km long fiber optic cable on Rhonegletscher, Switzerland, and gathered continuous DAS data. The cable followed the glacier’s central flow line starting in the lowest kilometer of the ablation zone and extending well into the accumulation area. Even for a relatively small mountain glacier such as Rhonegletscher, cable deployment was a considerable logistical challenge. However, initial data analysis illustrates the benefit compared to conventional cryoseismological instrumentation: DAS measurements capture ground deformation over many octaves, including typical high-frequency englacial sources (10s to 100s of Hz) related to crevasse formation and basal sliding as well as long period signals (10s to 100s of seconds) of ice deformation. Depending on the presence of a snow cover, DAS records contain strong environmental noise (wind, meltwater flow, precipitation) and thus exhibit lower signal-to-noise ratios compared to conventional on-ice seismic installations. This is nevertheless outweighed by the advantage of monitoring ground unrest and ice deformation of nearly an entire glacier. We present a first compilation of signal and noise records and discuss future directions to leverage DAS data sets in glaciological research. Conference Object Antarc* Antarctic glacier Greenland Ice Sheet ETH Zürich Research Collection Antarctic Greenland |
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Open Polar |
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ETH Zürich Research Collection |
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ftethz |
language |
English |
description |
Over the past 1-2 decades, seismological measurements have provided new and unique insights into glacier and ice sheet dynamics. At the same time, sensor coverage is typically limited in harsh glacial environments with littile or no access. Turning kilometer-long fiber optic cables placed on the Earth’s surface into thousands of seismic sensors, Distributed Acoustic Sensing (DAS) may overcome the limitation of sensor coverage in the cryosphere. First DAS applications on the Greenland and Antarctic ice sheets and on Alpine glacier ice have highlighted the technique’s superiority. Signals of natural and man-made seismic sources can be resolved with an unrivaled level of detail. This offers glaciologists new perspectives to interpret their seismograms in terms of ice structure, basal boundary conditions and source locations. However, previous studies employed only relatively small network scales with a point-like borehole deployment or < 1 km cable aperture at the ice surface. Here we present a DAS installation, which aims to cover the majority of an Alpine glacier catchment: For one month in summer 2020 we deployed a 9 km long fiber optic cable on Rhonegletscher, Switzerland, and gathered continuous DAS data. The cable followed the glacier’s central flow line starting in the lowest kilometer of the ablation zone and extending well into the accumulation area. Even for a relatively small mountain glacier such as Rhonegletscher, cable deployment was a considerable logistical challenge. However, initial data analysis illustrates the benefit compared to conventional cryoseismological instrumentation: DAS measurements capture ground deformation over many octaves, including typical high-frequency englacial sources (10s to 100s of Hz) related to crevasse formation and basal sliding as well as long period signals (10s to 100s of seconds) of ice deformation. Depending on the presence of a snow cover, DAS records contain strong environmental noise (wind, meltwater flow, precipitation) and thus exhibit lower signal-to-noise ratios compared to conventional on-ice seismic installations. This is nevertheless outweighed by the advantage of monitoring ground unrest and ice deformation of nearly an entire glacier. We present a first compilation of signal and noise records and discuss future directions to leverage DAS data sets in glaciological research. |
format |
Conference Object |
author |
Walter, Fabian Thomas Paitz, Patrick Fichtner, Andreas Edme, Pascal Gajek, Wojciech Lipovsky, Bradley P. Martin, Eileen |
spellingShingle |
Walter, Fabian Thomas Paitz, Patrick Fichtner, Andreas Edme, Pascal Gajek, Wojciech Lipovsky, Bradley P. Martin, Eileen Capturing Glacier-Wide Cryoseismicity With Distributed Acoustic Sensing |
author_facet |
Walter, Fabian Thomas Paitz, Patrick Fichtner, Andreas Edme, Pascal Gajek, Wojciech Lipovsky, Bradley P. Martin, Eileen |
author_sort |
Walter, Fabian Thomas |
title |
Capturing Glacier-Wide Cryoseismicity With Distributed Acoustic Sensing |
title_short |
Capturing Glacier-Wide Cryoseismicity With Distributed Acoustic Sensing |
title_full |
Capturing Glacier-Wide Cryoseismicity With Distributed Acoustic Sensing |
title_fullStr |
Capturing Glacier-Wide Cryoseismicity With Distributed Acoustic Sensing |
title_full_unstemmed |
Capturing Glacier-Wide Cryoseismicity With Distributed Acoustic Sensing |
title_sort |
capturing glacier-wide cryoseismicity with distributed acoustic sensing |
publisher |
Copernicus |
publishDate |
2021 |
url |
https://hdl.handle.net/20.500.11850/526299 https://doi.org/10.3929/ethz-b-000526299 |
geographic |
Antarctic Greenland |
geographic_facet |
Antarctic Greenland |
genre |
Antarc* Antarctic glacier Greenland Ice Sheet |
genre_facet |
Antarc* Antarctic glacier Greenland Ice Sheet |
op_source |
EGUsphere |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.5194/egusphere-egu21-5809 http://hdl.handle.net/20.500.11850/526299 doi:10.3929/ethz-b-000526299 |
op_rights |
info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/4.0/ Creative Commons Attribution 4.0 International |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/20.500.11850/526299 https://doi.org/10.3929/ethz-b-000526299 https://doi.org/10.5194/egusphere-egu21-5809 |
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1766259392899973120 |