GNGTS 2023 - Atti del 41° Convegno Nazionale

Session 1.1 GNGTS 2023 of the Gargano Promontory β , , , (Southern Italy) S. Lucente 1 , T. Ninivaggi 2 , S. de Lorenzo 1 , E. Del Pezzo 3, 4 , M. Filippucci 1 , G. Prosser 5 , A. Tallarico 1 1 Department of Earth and Geo-Environmental Science, University of Bari Aldo Moro (UniBa) 2 National Institute of Geophysics and Volcanology (INGV), Sezione Irpinia 3 National Institute of Geophysics and Volcanology (INGV), Osservatorio Vesuviano 4 Instituto Andaluz de Geofisica, Universidad de Granada, Granada, Spain 5 Department of Science, University of Basilicata (Unibas) The coda envelope analysis is one of the most significant methods for exploring the lithosphere physical behavior in terms of seismic scattering and attenuation. In this study, we examined the S-wave coda envelopes of 190 small earthquakes ( ranging from 1.0 to 2.8) in the Gargano Promontory (GP, Apulia region, Southern Italy), recorded by OTRIONS local seismic network (Tallarico, 2013; Filippucci et al., 2021a) and by INGV national seismic network, to estimate , , β and quality factors at the frequencies of 3, 4, 5, 6, 8, 10 and 12 Hz ( Fig. 1 ). We obtained applying the coda normalization method proposed by Aki (1980) and coda β parameter applying Aki’s (1969) method, for the same volume of crust. For processing, we selected the coda envelope in the windows ranged from 1.5 up to 30 seconds after the origin time (lapse time, ). Then we separated the intrinsic and scattering quality factors by adopting Wennerberg’s (1993) method. All the obtained quality factors show a clear dependence with the frequency. The are comparable to the ones recently obtained by Filippucci et al. (2021b), using a different selection of data. The estimated are similar to at all frequencies and range between 100 and 1000. The parameter shows higher values than , except for 8 Hz, where the two estimates are closer.