During May 2022, a short-lived seismic swarm affected a small area of the Chianti fiorentino region about 15 km south of Florence. The two strongest earthquakes of the swarm reached MW 3.7; nonetheless, they were distinctly felt up to distances of several tens of kilometers, causing residents’ concern. Moreover, the presence of a huge artistic heritage in the surrounding areas raises questions about its vulnerability to even minor ground shaking. In order to improve knowledge of the location and size of active seismogenic structures in the vicinity of Florence, the Istituto Nazionale di Geofisica e Vulcanologia (INGV) responded promptly through the SISMIKO emergency group. On the 4th of May, the day after the beginning of the sequence, five mobile seismic stations were installed at close range from the epicentral area and integrated into the INGV permanent monitoring system. This report describes the procedures related to: (i) deployment, maintenance and dismission of the mobile network; (ii) management and quality control of the acquired data. Finally, in the frame of the seismo-tectonic context of the area, we present a preliminary overview about the spatial features and temporal evolution of the swarm which had a slight resumption in August 2022, with a magnitude 2.7 event and its aftershocks.
Published: 2023-04-06