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 insulatin...

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Bibliographic Details
Published in:Nature Communications
Main Authors: Podolskiy, Evgeny A., Murai, Yoshio, Kanna, Naoya, Sugiyama, Shin
Other Authors: MEXT | Japan Society for the Promotion of Science
Format: Article in Journal/Newspaper
Language:English
Published: Springer Science and Business Media LLC 2021
Subjects:
Online Access:http://dx.doi.org/10.1038/s41467-021-24142-4
http://www.nature.com/articles/s41467-021-24142-4.pdf
http://www.nature.com/articles/s41467-021-24142-4
Description
Summary: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.