Dense nodal seismic array temporary experiment on Alpine Glacier of Argentière (RESIF-SISMOB)

Seismology can yield key observational insights on glacier dynamical processes and structure characteristics. Spatializing the information gained from seismic signals however requires the deployment of dense seismic arrays, which has recently become routine in a wide range of geophysical contexts but has remained limited in glaciated environments. Here we present a dense seismic array experiment made of 98, 3-component and 35-days-long continuous records acquired in early spring on the Argentière Glacier, French Alps. The seismic dataset is supplemented by a wide range of complementary observations obtained from ground penetrating radar, drone imagery, GPS positioning and in-situ instrumentation of basal glacier sliding velocities and water flow discharge. Our objective is to provide a comprehensive dataset that enables (i) investigating with unprecedented spatial definition a wide range of glacier seismic sources and structural characteristics associated with e.g. englacial fracturing, ice-bed sliding or englacial and subglacial water flow, as well as (ii) linking these seismically-derived findings to spatial and temporal changes in the overall glacier dynamics and structure. We argue that the present dataset gathers all the necessary components to reach these objectives. We report that important dynamical and structural changes occur during the seismically monitored time period and spatial area. We also conduct a wide range of classical seismic processing techniques including amplitude analysis, event picking from pattern matching and systematic beamforming that suggest a wide range of glacier sources and structural changes are detectable with our dense seismic array and their spatial and temporal dynamics may be studied in details in future studies.