Brief communication: On the potential of seismic polarity reversal to identify a thin low-velocity layer above a high-velocity layer in ice-rich rock glaciers
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Published:2024-07-16
Issue:7
Volume:18
Page:3231-3236
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ISSN:1994-0424
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Container-title:The Cryosphere
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language:en
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Short-container-title:The Cryosphere
Author:
Boaga JacopoORCID, Pavoni MirkoORCID, Bast AlexanderORCID, Weber SamuelORCID
Abstract
Abstract. Seismic refraction tomography is a commonly used technique to characterise rock glaciers, as the boundary between unfrozen and ice-bearing layers represents a strong impedance contrast. In several rock glaciers, we observed a reversed polarity of the waves refracted by an extended ice-bearing layer compared to direct-wave arrivals. This phase change may be related to the presence of a thin low-velocity layer (LVL), such as fine- to coarse-grained sediments, above a thicker ice-rich layer. Our results are confirmed by the modelling and analysis of synthetic seismograms to demonstrate that the presence of a low-velocity layer can produce a polarity reversal on the seismic gather.
Funder
Ministero dell’Istruzione, dell’Università e della Ricerca
Publisher
Copernicus GmbH
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