EGU21-8617
https://doi.org/10.5194/egusphere-egu21-8617
EGU General Assembly 2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.

Frost quakes – the sound of a dynamic cryosphere and a convenient source for passive surface wave imaging of permafrost

Rowan Romeyn1,2, Alfred Hanssen1,2, Andreas Köhler1,3, Bent Ole Ruud2,4, Helene Meling Stemland2,4, and Tor Arne Johansen2,4,5
Rowan Romeyn et al.
  • 1Department of Geosciences, University of Tromsø – The Arctic University of Norway, 9037 Tromsø, Norway
  • 2Research Centre for Arctic Petroleum Exploration (ARCEx)
  • 3NORSAR, 2007 Kjeller, Norway
  • 4Department of Earth Science, University of Bergen, 5007 Bergen, Norway
  • 5The University Centre in Svalbard (UNIS), 9171 Longyearbyen, Norway

A class of short-duration seismic events were recorded on dense, temporary geophone arrays deployed in Adventdalen, Svalbard in spring and autumn 2019. A similar class of events have also been detected in seismic records from the SPITS seismic array located on Janssonhaugen in Adventdalen, that has been in continuous operation since the 1990’s. In both cases, estimated source positions are dominantly local and cluster around frost polygon, ice-wedge geomorphologies. Correlation with periods of rapidly cooling air temperature and consequent thermal stress build-up in the near surface are also observed. These events are consequently interpreted as frost quakes, a class of cryoseism. The dense, temporary arrays allowed high quality surface-wave dispersion images to be generated, that show potential to monitor structure and change in permafrost through passive seismic deployments. While the lower wavenumber resolution of the sparser SPITS array is less suited to imaging the near-surface in detail, the long continuous recording period gives us a unique insight into the temporal occurrence of frost quakes. This allows us, for example, to better understand the dynamic processes leasing to frost quakes by correlating temporal occurrence with models of thermal stress in the ground, constrained by thermistor temperature measurements from a nearby borehole.

How to cite: Romeyn, R., Hanssen, A., Köhler, A., Ruud, B. O., Stemland, H. M., and Johansen, T. A.: Frost quakes – the sound of a dynamic cryosphere and a convenient source for passive surface wave imaging of permafrost, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-8617, https://doi.org/10.5194/egusphere-egu21-8617, 2021.

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