Abstract
On November 11, 2019 at 10:52 a 5.2 MLv earthquake occurred near Montélimar. As part of this "Active Faults" theme of the "Seismic and Seismic Hazard of Metropolitan France" axis of the Transversal Reactive Seismicity Action, a team of eight scientists from four structures (Géosciences Montpellier, IRSN, Géoazur, ISTerre) arrived in the area on November 13. They focus their exploration on the trace identified the day before by radar interferometry (InSAR). In total, they observed about fifteen point breakpoints distributed over a 4 km length. As shown in this photo, some of these clues are scanned with a laser (LiDAR) to accurately quantify the ground deformation. The "Active Faults" theme of the "Seismic and Seismic Hazard of Metropolitan France" axis of the transverse action Repressive Seismicity was created in November 2017. It brings together geologists and geophysicists from six organizations (IRSN, BRGM, EDF, CEA-LDG, GEOTER-FRUGO and ANDRA), some of whom are outside Résif. Its objective: to better understand seismotectonics, the processes that control active deformation, and seismic hazard in metropolitan France.This national research infrastructure is dedicated to the observation and understanding of the structure and dynamics of the Inner Earth. Résif is based on high-tech observation networks, composed of seismological, geodetic and gravimetric instruments deployed in a dense manner throughout France. The data collected make it possible to study with high spatial and temporal resolution the deformation of the ground, surface and deep structures, seismicity on a local and global scale and natural hazards, and more particularly seismic events, on French territory. Résif is integrated into European (EPOS - European Plate Observing System) and global systems of instruments for imaging the Earth's interior as a whole and studying many natural phenomena. Within Résif, the transverse seismicity action coordinates all the work on seismicity within a single structure with the objective of increasing the efficiency of the work carried out and increasing its visibility. This includes the production and distribution of products derived from Résif data based on knowledge of French seismicity and associated hazard.