GNGTS 2024 - Atti del 42° Convegno Nazionale

Session 1.1 GNGTS 2024 OTRIONS seismic network afer ten years of operaton: the new seismic catalog A. Ferreri 1 , A. Romeo 2 , R. Giannuzzi 1 , G. Cecere 2 , S. de Lorenzo 1 , L. Falco 2 , M. Filippucci 1,2 , M. Michele 2 , G. Selvaggi 2 , A. Tallarico 1,2 1 Dipartmento di Scienze della Terra e Geoambientali, Università degli Studi di Bari Aldo Moro, Bari, Italy 2 Isttuto Nazionale di Geofsica e Vulcanologia, Italy The OTRIONS seismic network (FDSN network code OT) is a local network installed in the Apulia region (Southern Italy) with the aim of monitoring the seismicity of the Gargano area (Northern Apulia) and the Salento area (Southern Apulia). The OT network is managed by the University of Bari Aldo Moro (UniBa) and by the Natonal Insttute of Geophysics and Volcanology (INGV). It started to operate in 2013 and in 2019 the recording statons migrated to EIDA (all details can be found in Filippucci et al., 2021a). In 2021 a frst database was collected, with the event detecton achieved both manually and automatcally with SeisComP3 (Helmholtz-Centre Potsdam), and was released ( Filippucci et al., 2021a; Filippucci et al., 2021b). Afer ten years of operatons, we focus on the microseismicity of the Gargano area with the aim of collectng a new seismic database for the period from April 2013 to December 2022, by using a recently acquired sofware, CASP (Complete Automatc Seismic Processor), for the automatc detecton, picking and locaton of seismic events (Scafdi et al., 2019). The CASP sofware is installed on a remote server implemented by RECAS-Bari, the computatonal infrastructure of INFN and UniBa. Through an appropriate parameter setng, we adapted CASP and NonLinLoc (Lomax et al., 2000) to the Gargano area and to the seismic statons available, both OT and INGV permanent seismic networks. We used the 1D velocity model of Gargano developed by de Lorenzo et al., (2017). The recorded seismic events were organized in two catalogs: the frst one is the automatc catalog, obtained from the automatc locatons of CASP; the second one is the manual catalog, obtained through a manual revision of P and S waves arrival tmes. To evaluate the reliability of CASP, a comparison between the automatc and manual catalog was performed. From a comparison of the manual catalog with the already released catalog of the Gargano seismicity (Filippucci et al., 2021b), the number of events detected by CASP increased a lot. Furthermore, the results show that the choice of the CASP parameters allows us to lower the minimum magnitude threshold of the recorded microseismicity in the Gargano area. Preliminary analysis of the earthquake's foci shows that the seismicity patern retrace, substantally, the same discussed in the work of Miccolis et al., (2021).