People in charge
Researchers: Mathilde Radiguet (responsible, OSUG), Clément Hibert (EOST), Agnès Helmestetter (OSUG)
IT: Marc Grunberg (EOST), Gael Janex (OSUG), Mohammed Benbachir (EOST)
Objectives
The task of the OMIV Seismology Data Centre (OMIV-Seismo) is to acquire, store and disseminate seismological information related to landslide dynamics through a network of permanent seismic stations. The Data Centre comprises unstable slopes where a permanent seismic network is maintained (Séchilienne, La Clapière, Super-Sauze, Avignonet, Saint-Eynard) and unstable slopes where temporary seismic networks (from a few months to a few years) have been installed (Chambon, Villerville, Aiguilles, Cap d'Ailly, Porsmillin, Pégairolles).
The objectives of OMIV-Seismo are:
- to acquire continuous seismological records on two categories of unstable slopes (continuously moving slides and cliffs affected by rockfalls);
- to detect the endogeneous micro-seismicity and characterize these events (location, energy, duration, mechanism);
- to record small local earthquakes very close to the unstable slopes and which are too small to be detected by national/regional seismic networks (ReNass, SISMALP). The focus is the activity of the Belledone Fault (near Séchilienne landslide) and the Serenne Fault (near Super-Sauze landslide);
- to monitor the landslide response to regional earthquakes (e.g. the signal of regional earthquakes recorded on the landslide) and assess possible site effects (linked to the topography of the slope or the existence of damaged rocks).
In addition, on some unstable slopes, seismic noise is analyzed by characterizing the Green function between two seismometers in order to detect very small changes in the material properties.
The data of the OMIV seismic stations are processed automatically every day but the seismic catalogue are only published (data centre, website) after expert (manual) validation. Procedures for an automated process of classification are currently being implemented. The Data Centre is hosted by RESIF.
OMIV Instrumentation
Status in September 2018 (for the OMIV permanent networks):
- Séchilienne:
- La Clapiére: 2 seismic arrays (6 x 1C sensor + 1 x 3C sensor)
- Super-Sauze: 2 seismic arrays (3 x 1C sensor + 1 x 3C sensor)
- Avignonet: 3 seismic stations (3 x 3C sensors)
- Saint-Eynard: