Researchers Map Glacier Crevasse Evolution Using Advanced Seismic Techniques at Hansbreen, Svalbard
Researchers have developed a two-step seismic workflow combining Matched Field Processing and source relocation to track crevasse formation on Hansbreen glacier in Svalbard with metre-scale precision. The study measured crevasse propagation rates and diffusion coefficients (0.47–0.55 m²/s), interpreting the cracking mechanism as sustained subcritical crack propagation governed by viscous stress relaxation. The findings help fill a critical observational gap in understanding how crevasses control glacier dynamics, meltwater routing, and the transition between brittle and viscous ice behaviour.
A study published in AGU's journal and posted to arXiv presents a novel two-step cryoseismic workflow designed to map glacial surface fracturing at metre-scale resolution, even under sparse or irregular sensor array conditions. Applied to Hansbreen glacier in Svalbard, the method combines Matched Field Processing (MFP) — which detects surface icequakes and characterises meltwater noise — with a discrete arrival-time relocation procedure that sharpens the spatial accuracy of icequake locations. The improved localisation enabled researchers to identify active crevasse opening episodes and estimate propagation rates, yielding diffusion coefficients of 0.47 to 0.55 m²/s. The team interprets the dominant crevassing mechanism as subcritical crack propagation, in which viscous stress relaxation drives fracture rates many orders of magnitude below elastic failure limits, representing a brittle-to-viscous regime transfer. These results address a longstanding scarcity of direct observational data on crevasse propagation, which is important because crevasses influence both ice dynamics and the routing of meltwater through and beneath glaciers. The work demonstrates that dense-array seismic techniques can be meaningfully adapted for deployment in logistically constrained glacial environments.
What's missing
It is unclear how representative Hansbreen's conditions are of other glacier types or climatic settings, and the seasonal or temporal scope of the seismic monitoring campaign is not specified. Long-term validation of the diffusion coefficients against independent field measurements (e.g., GPS or drone surveys of crevasse geometry) is not discussed.
What different sources said
- arXiv physicsCenter
Surface Crevasse Evolution Observed Using Matched Field Processing and Source Relocation at Hansbreen, Svalbard
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