arXiv subjects

Florent Gimbert

Publications and source records attributed to Florent Gimbert.

3 recordsLinked to original sources

arXiv2026

Environmental seismology: What can we learn on earth surface processes with ambient noise?

Environmental seismology investigates mechanical vibrations generated by external processes or influenced by phenomena originating outside the solid Earth. It encompasses interactions between the solid Earth and other environmental systems, including the cryosphere, hydrosphere, and anthroposphere, as well as the specific sources of seismic vibrations associated with these systems. This field also examines how environmental factors, such as temperature fluctuations and hydrological variations, affect seismic wave propagation. Recent advances in data-processing techniques, combined with increased computational capabilities and the growing density of seismic sensor networks, have enabled novel observations and contributed to the emergence of environmental seismology as a distinct research field. This article reviews how subtle changes in the Earth's subsurface can be detected and interpreted through variations in seismic wave propagation induced by external environmental processes, with applications to geomechanics, hydrology, and natural hazard assessment. In particular, we demonstrate how ambient seismic noise can be used to monitor: (1) thermal variations in the subsurface, within buildings, and in rock columns; (2) the temporal and spatial evolution of groundwater levels; and (3) changes in the rigidity of the material forming a landslide, with particular emphasis on the reduction in rigidity that may precede slope failure.

physics.geo-ph↗

arXiv2020

The RESOLVE project: a multi-physics experiment with a temporary dense seismic array on the Argentière Glacier, French Alps

Recent work in the field of cryo-seismology demonstrates that high frequency (>1 Hz) waves provide key constraints on a wide range of glacier processes such as basal friction, surface crevassing or subglacial water flow. Establishing quantitative links between the seismic signal and the processes of interest however requires detailed characterization of the wavefield, which at the high frequencies of interest necessitates the deployment of large and particularly dense seismic arrays. Although dense seismic array monitoring has recently become routine in geophysics, its application to glaciated environments has yet remained limited. Here we present a dense seismic array experiment made of 98 3-component seismic stations continuously recording during 35 days 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, GNSS positioning and in-situ instrumentation of basal glacier sliding velocities and subglacial water discharge. Through applying multiple processing techniques including event detection from template matching and systematic beamforming, we demonstrate that the present dataset provides enhanced spatial resolution on basal stick slip and englacial fracturing sources as well as novel constraints on heterogeneous nature of the noise field generated by subglacial water flow and on the link between crevasse properties and englacial seismic velocities. We finally outline in which ways further work using this dataset could help tackle key remaining questions in the field.

physics.geo-ph↗

arXiv2013

Crossover from quasi-static to dense flow regime in compressed frictional granular media

We investigate the evolution of multi-scale mechanical properties towards the macroscopic mechanical instability in frictional granular media under multiaxial compressive loading. Spatial correlations of shear stress redistribution following nucleating contact sliding events and shear strain localization are investigated. We report growing correlation lengths associated to both shear stress and shear strain fields that diverge simultaneously as approaching the transition to a dense flow regime. This shows that the transition from quasi static to dense flow regime can be interpreted as a critical phase transition. Our results suggest that no shear band with a characteristic thickness has formed at the onset of instability.

cond-mat.stat-mech↗