Dataset Information

Ocean-bottom and surface seismometers reveal continuous glacial tremor and slip.

ABSTRACT: Shearing along subduction zones, laboratory experiments on analogue faults, and sliding along glacier beds are all associated with aseismic and co-seismic slip. In this study, an ocean-bottom seismometer is deployed near the terminus of a Greenlandic tidewater glacier, effectively insulating the signal from the extremely noisy surface seismic wavefield. Continuous, tide-modulated tremor related to ice speed is recorded at the bed of the glacier. When noise interference (for example, due to strong winds) is low, the tremor is also confirmed via analysis of seismic waveforms from surface stations. The signal resembles the tectonic tremor commonly observed during slow-earthquake events in subduction zones. We propose that the glacier sliding velocity can be retrieved from the observed seismic noise. Our approach may open new opportunities for monitoring calving-front processes in one of the most difficult-to-access cryospheric environments.

SUBMITTER: Podolskiy EA

PROVIDER: S-EPMC8225613 | biostudies-literature | 2021 Jun

REPOSITORIES: biostudies-literature

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Ocean-bottom and surface seismometers reveal continuous glacial tremor and slip.

Podolskiy Evgeny A EA Murai Yoshio Y Kanna Naoya N Sugiyama Shin S

Nature communications 20210624 1

Shearing along subduction zones, laboratory experiments on analogue faults, and sliding along glacier beds are all associated with aseismic and co-seismic slip. In this study, an ocean-bottom seismometer is deployed near the terminus of a Greenlandic tidewater glacier, effectively insulating the signal from the extremely noisy surface seismic wavefield. Continuous, tide-modulated tremor related to ice speed is recorded at the bed of the glacier. When noise interference (for example, due to stron ...[more]

PMID: 34168146

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Dataset Information

Ocean-bottom and surface seismometers reveal continuous glacial tremor and slip.

Publications

Ocean-bottom and surface seismometers reveal continuous glacial tremor and slip.

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