Teil Earthquake

**Description of the project

"An earthquake Mw 5 occurred on November 11, 2019 in the vicinity of Le Teil, in Ardèche. The earthquake resulted in a surface rupture along a fault zone of about 4 km, between Le Teil and Saint-Thomé. The depth of the very superficial focus is about 1 km. The reverse fault slip is about 30 cm at the focus according to the inversion of the InSAR data; at the surface it reaches about 10 cm according to field measurements which show deformations aligned with the fault identified by InSAR. The occurrence of an earthquake of such magnitude in metropolitan France, at such a shallow depth, associated with a particularly low number of aftershocks, makes it an earthquake with atypical characteristics. The geophysical networks are very sparse in this region with major societal and industrial issues, including those concerning the nuclear industry. The need to follow the evolution of the surface deformation requires the maintenance of the geodetic installation, the acquisition of new measurements to constrain the properties of the environment, the acquisition of observables (projected objects) to calibrate the simulations of ground motion during the earthquake, and the programming of paleoseismic trench(s) to evaluate the recurrence of similar earthquakes on the fault or, conversely, to show the singularity of this earthquake over the last 10,000 years and to better understand its mechanism".