GNGTS 2024 - Atti del 42° Convegno Nazionale

Session 1.1 GNGTS 2024 As our main goal is to obtain informaton about the seismicity and the seismic actvity of the faults in the surroundings of the Farneto del Principe’ dam, we will focus only on events within a constrained area around the dam (Fig. 1). We remove the deep events as they are not related to the same tectonic context of the fault system we are interested in. These criteria give us a list of about 150 events (Fig. 1). Fig. 1 - Seismic actvity on the Esaro valley, Northern Calabria, Italy (1985-2023) One of the main problems for using diferent catalogues is that the same event can have a slightly diferent localisaton depending on the catalogue. Since we are studying a very local area, we need to harmonise our list and have the most precise locaton as possible for each event. Thus, we collect waveforms from the University of Calabria’ network, for every event in our new dataset. This will allow us to do, for each staton and event, a re-picking of the P- and S- phases, in order to perform a uniform re-localisaton of our selected earthquakes. The re-localisaton process is ongoing and is carried out using diferent codes: Hypo71 ( Lee et al., 1972 ), HypoEllipse ( Lahr, 2012 ) and Hyposat ( Schweitzer, 2001 ). First results show that a small part of the re-localised events has now migrated out of the area of interest, mainly on the west and the northeastern sides. Another interestng feature is a kind of clustering with an E-W trend and 5-20 km deep, just eastwards of the dam. In our study area, we only have earthquakes with small magnitudes (maximum M≈3) so the focal mechanisms were not released by the natonal and internatonal agencies. We can now analyse our re-localised events to have indicatons about the stress regime and the kinematcs of the fault.