GNGTS 2024 - Atti del 42° Convegno Nazionale

Session 1.1 GNGTS 2024 A preliminary computaton of the seismic coupling for Italy F. Sparacino 1 , B. G. Galuzzi 2 , M. Palano 1 1 - Isttuto Nazionale di Geofsica e Vulcanologia, Osservatorio Etneo - Sezione di Catania, Catania, Italy. 2 - Isttuto di Bioimmagini e fsiologia molecolare, CNR, Milano, Italy. In the last two decades, the worldwide growth of contnuous and episodic GNSS statons as well as the seismic networks allowed the acquisiton of extensive geodetc and seismological datasets. This aspect has recently allowed the possibility of comparing geodetc and seismic strain-rates at the scale of regional fault systems. Studies focusing on this topic have provided new insights on the parttoning between fault slip and bulk lithosphere permanent strain (Ferrant et al., 2014; Carafa et al., 2017, 2020). The basic idea is that, for a given region, the moment released by earthquakes mirrors the rate of tectonic deformaton (Kostrov, 1974). Achieved results have allowed to identfy regions where the crustal deformaton budget is entrely released by seismicity (e.g. Mazzot et al., 2011; Pancha et al., 2006; D’Agostno, 2014; Sparacino et al., 2020), as well as regions where the excess deformaton can be released either as aseismic slip across faults or through large future earthquakes (Masson et al., 2005; Palano et al., 2018, 2020, Déprez, et al., 2013; Sparacino et al., 2022). Here we provided a preliminary computaton for Italy by adoptng the seismogenic zonaton of Melet et al. (2004). To this aim, we compiled catalogs for both historical (since 1005) and instrumental crustal seismicity occurring in the investgated area (since 1985; htp:// iside.rm.ingv.it/) . These catalogs have been used to estmate the seismic moment-rates along with the expected maximum magnitude, the seismogenic thickness, and the Gutenberg-Richter parameters. In additon, based on an updated GNSS velocity feld we derived the geodetc moment-rates. References Carafa M.M., Valensise G. and Bird P.; 2017: Assessing the seismic coupling of shallow contnental faults and its impact on seismic hazard estmates: a case-study from Italy. Geophys. J. Int., 209(1), 32-47, DOI 10.1093/gji/ggx002. Carafa M.M., Galvani A., Di Naccio D., Kastelic V., Di Lorenzo C., Miccolis S., Sepe V., Pietrantonio G., Gizzi C., Massucci A., Valensise G. and Bird P.; 2020: Parttoning the ongoing extension of the central Apennines (Italy): Fault slip rates and bulk deformaton rates from geodetc and st ress data . J . Geophys . Res . : So l i d Ear th, 125(7) , e2019JB018956 , DOI 10.1029/2019JB018956.