Researchers Map Glacier Crevasse Evolution Using Advanced Seismic Techniques at Hansbreen, Svalbard
Scientists used matched field processing and seismic source relocation to map crevasse propagation on Hansbreen glacier in Svalbard with meter-scale precision. The study combines two seismic analysis methods to overcome limitations of sparse instrumentation and detect surface ice fractures and meltwater noise. The findings provide rare observational data on crevasse propagation rates and advance understanding of how glaciers fracture and evolve.
Researchers developed a two-step workflow combining matched field processing (MFP) and discrete arrival time relocation to analyze seismic activity at the surface of Hansbreen glacier in Svalbard. The approach addresses a key challenge in cryoseismology: precise localization of ice-fracturing events with limited seismic instrumentation. By applying this method, the team detected surface icequakes, characterized meltwater-generated noise, and tracked ongoing crevasse opening episodes with meter-scale resolution. The analysis revealed crevasse propagation rates and calculated diffusion coefficients of 0.47 to 0.55 m² per second. The results suggest that crevasse propagation occurs through sustained subcritical crack propagation, where viscous stress relaxation—rather than purely elastic fracture mechanics—governs the process at rates significantly below theoretical elastic limits.
What's missing
The study does not discuss broader implications for glacier stability, sea-level rise projections, or how findings from this single glacier site may generalize to other glacial systems. The paper also does not address limitations in temporal resolution of the seismic monitoring or how seasonal variations might affect the observed propagation rates.
What different sources said
- arXiv physicsCenter
Surface Crevasse Evolution Observed Using Matched Field Processing and Source Relocation at Hansbreen, Svalbard
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