4 Citations
On May 24, 2011, at 12.40 UTC, the Istituto Nazionale di Geofisica e Vulcanologia (INGV) recorded the beginning of a seismic sequence in the Montefeltro area (Province of Forlì-Cesena, Italy) of modest magnitude. In the following two weeks, over 600 events were localized by the INGV Seismic Surveillance Room, of which 13 of ML ≥ 3.0. Eight of these more energetic events occurred within the first 16 hours of the first shock. The highest energy event occurred on the night between 24 and 25 May (2011-05-04 22:03:51 utc) with a magnitude of ML 3.9.
Considering the peculiar evolution of the sequence in the first 24 hours from the first event, the proximity of the epicentral area to the Alta Val Tiberina (Central Italy), it was deemed appropriate to activate response procedures to a seismic emergency and prepare an intervention aimed at improving the instrumental coverage of the area.
On May 25, a temporary seismic network was installed to integrate the permanent stations already present in the area (FDSN code= IV, doi: https://doi.org/10.13127/SD/X0FXNH7QFY) with local data acquisition.