Seismic monitoring of landslides using ambient seismic noise : compared analysis of various landslides in France

5 to 6 months (between January and July 2024)

Landslides represent a serious threat to populations and infrastructures. Monitoring landslide activity allows to detect episodes of reactivation, as well as their controlling factors such as hydro-meteorological conditions and water infiltration. When available, measurements of landslide surface deformation can be used to detect destabilizations and rupture precursors. However, this type of measurement is not always available and may not be representative of the landslide dynamics over the volume involved. In recent years, it has been demonstrated that ambient seismic noise interferometry can be used to monitor the mechanical damaging of a rock volume. Temporal variations in seismic surface wave velocities (dV/V) can be estimated from continuous seismic records using ambient noise correlations. Previous studies (e.g. Larose et al. 2015) have shown that dV/V time series generally reveal seasonal variations that are associated to seasonal parameters (temperature and rainfalls). In addition, dramatic drops in dV/V correspond to rheological changes associated with a landslide reactivation.

Seismic noise interferometry is thus a useful tool for landslide monitoring, which has already been applied to landslides in France (Fiolleau et al. 2020) and in the world (Larose et al. 2015, Bontemps et al. 2020, Xie et al. 2023). In this Master project, our goal is to test the systematic use of seismic interferometry to monitor landslides instrumented as part of the National landslide Observatory OMIV (http://www.ano-omiv.cnrs.fr/). Within OMIV, several landslides in France are monitored over long time scales with multi-observable measurements : (i) meteorological and hydrological parameters (ii) surface displacements (GNSS, total stations) and (iii) seismic recordings, which allow to detect seismic events related to landslide activity (quakes, rockfalls). Although these continuous seismic records are available at most sites, they have not been exploited in a systematic manner to monitor landslide rheological changes.

The study will focus on 3 landslides well instrumented in the Alps : Séchilienne, Harmalière and La Clapière. For each site we will compute dV/V time series in different frequency bands and for various stations and components. This will allow us to design for each site the optimal set of parameters that allows to capture both that may vary depending on the landslide geological and geometrical characteristics, water table depth ect… We will then analyse dV/V time series over several years, identifying seasonal variations as well as possible reactivations, in relation with hydro-meteorological conditions, and in relation with other available data such as seismic events activity and surface deformation.

This Master project will bring new insight into the systematic use of seismic noise interferometry for landslide monitoring.

Although the Master’s project will mostly consist in data analysis, the intern may also be involved in field work, taking part in instrumentation campaigns and/or instrument maintenance on landslides in the Alps.

References :

S Fiolleau, D Jongmans, G Bièvre, G Chambon, L Baillet, B Vial, Seismic characterization of a clay-block rupture in Harmalière landslide, French Western Alps, Geophysical Journal International, Volume 221, Issue 3, June 2020, Pages 1777–1788, https://doi-org.insu.bib.cnrs.fr/10.1093/gji/ggaa050
Bontemps, N., Lacroix, P., Larose, E. et al. Rain and small earthquakes maintain a slow-moving landslide in a persistent critical state. Nat Commun 11, 780 (2020). https://doi-org.insu.bib.cnrs.fr/10.1038/s41467-020-14445-3
F. Xie, E. Larose, Q. Wang, Y. Zhang, S. Dai, H. Huang and C. Xu : In situ monitoring of rock slope destabilization with ambient seismic noise interferometry in southwest China , Eng. Geol. 312, 106922 (2023).
E. Larose, S. Carrière, C. Voisin, P. Bottelin, L. Baillet, P. Guéguen, F. Walter, D. Jongmans, B. Guillier, S. Garambois, F. Gimbert, C. Massey : Environmental seismology : what can we learn from ambient seismic noise ?, J. Appl. Gephys., 116, 62-74,(2015).

To apply : send CV + motivation letter to Mathilde Radiguet (mathilde.radiguet univ-genoble-alpes.fr)