Sismogrammes du séisme de Strasbourg du 26 juin 2021, enregistrés par les stations situées à moins de 20 km de l'épicentre

The BSCF-ReNaSS, a national service hosted by the Ecole et Observatoire des Sciences de la Terre (Eost) in Strasbourg exploiting data from the French Resif stations and some stations of the networks of bordering countries, recorded on June 26, 2021 at 05:00 local time, an earthquake of magnitude 3.9 (Mlv). Located about ten kilometers north of Strasbourg (epicenter located in the town of La Wantzenau), this earthquake follows many others since November 2019. This induced earthquake was followed by a second of magnitude 2.3 five minutes later. They are part of a series of more than 100 events recorded since November 2019 (including a magnitude 3.5 earthquake on December 4, 2020). The study of these earthquakes and the mechanisms at work at depth is still ongoing, while the activities of the company Fonroche on the Geoven geothermal site located in the area, were stopped in December 2020. The stations whose code begins with "AM" are stations of a temporary network deployed especially for the monitoring of this seismic crisis. The "FR" stations are stations of the Permanent Broadband Network (RLBP) of the French Seismological and Geodetic Network (Resif-Epos). Resif-Epos is a national research infrastructure dedicated to the observation and understanding of the structure and dynamics of the internal Earth. Resif is based on high technology observation networks, composed of seismological, geodetic and gravimetric instruments deployed in a dense way on the whole French territory. The data collected allow to study with a high spatio-temporal resolution the ground deformation, the superficial and deep structures, the seismicity at the local and global scale and the natural hazards, and more particularly the seismic ones, on the French territory. Resif is part of the European (EPOS - European Plate Observing System) and global systems of instruments allowing to image the interior of the Earth in its entirety and to study many natural phenomena.