GNGTS 2019 - Atti del 38° Convegno Nazionale

48 GNGTS 2019 S essione 1.1 during the two recent seismic sequences and the presence of an unruptured area between these two portions. In this context, we use the Coulomb stress changes to examine the interaction between the recent earthquakes that struck central Italy and the potential state of stress of the unruptured portions of the Campotosto fault. We find that the occurrence of the January 18 earthquakes caused an increase of stress in the upper central portion of the fault, just below the Campotosto lake, and on the deeper portions of the fault. The areas of the Campotosto fault positively stressed by the previous seismic sequences may be characterized by velocity strengthening behaviour (e.g., Boatwright and Cocco, 1996) releasing stress increases with aseismic slow deformation. On the other hand, these parts of the fault may be velocity weakening and represent an area that remained locked and acted as a barrier during the recent earthquake sequences. Finally, while the recent moderate seismic events occurring from 2009 to 2017 released accumulated strain through a series of moderate M~5 events, there is paleoseismological evidence of large surface-rupturing events (M >6.5; e.g., Galadini and Galli, 2003). We suggest, therefore, that the Campotosto fault releases accumulated tectonic strain through a wide range of magnitudes, and a heterogeneous behaviour. References Boatwright J., Cocco M.; 1996: Frictional constraints on crustal faulting. J. Geophys. Res., 101 , 13895-13909. Boncio P., Lavecchia G., Milana G., Rozzi B.; 2004: Seismogenesis in Central Apennines, Italy: An integrated analysis of minor earthquake sequences and structural data in the Amatrice-Campotosto area. Ann. Geophys., 47 , 1723-1742. Buttinelli M., Pezzo G., Valoroso L., De Gori P., Chiarabba C.; 2018: Tectonic Inversions, Fault Segmentations, and Triggering Mechanisms in the Central Apennines Normal Fault System: Insights from High-Resolution Velocity Models. Tectonics, 37 , 4135-4149. Cheloni D., Giuliani R., D’Anastasio E., Atzori S., Walters R.J., Bonci L., D’Agostino N., Mattone M., Calcaterra S., Gambino P.; 2014: Coseismic and post-seismic slip of the 2009 L’Aquila (central Italy) Mw 6.3 earthquake and implications for seismic potential along the Campotosto fault from joint inversion of high-precision levelling, InSAR and GPS data. Tectonophysics, 622 , 168-185. Galadini F., Galli P.; 2003: Paleoseismology of silent faults in Central Apennines (Italy): The Mt. Vettore and Laga Mts. faults. Ann. Geophys., 815-836. Galli P., Galadini F., Pantosti D.; 2008: Twenty years of paleoseismology in Italy. Earth-Sci. Rev., 88 , 89-117. CATALOGO COMPLETO DELLA SEQUENZA SISMICA DI AMATRICE-VISSO- NORCIA (ITALIA CENTRALE, BOLLETTINO SISMICO ITALIANO 2016-2018) M.G. Ciaccio, L. Margheriti, D. Latorre, B. Castello, A. Nardi, F.M. Mele, P. Baccheschi, A. Lisi, A. Marchetti, A.M. Lombardi, L. Improta, M. Moretti, M. Quintiliani, V. Lauciani, A. Bono, S. Pintore, Bollettino Sismico Italiano Working Group http://terremoti.ingv.it/en/bsi INGV National Institute of Geophysics and Volcanology, Roma, Italy In questo lavoro presentiamo il catalogo completo delle localizzazioni dei terremoti appartenenti alla più importante sequenza sismica avvenuta in Italia negli ultimi 30 anni, ovvero la sequenza sismica di Amatrice-Visso-Norcia (AVN) iniziata il 24 Agosto del 2016 in Appennino centrale. Si tratta di 102,582 eventi sismici registrati dalle 129 stazioni della Rete Sismica Nazionale (RSN, http://doi.org/10.13127/SD/X0FXNH7QFY ) e della rete temporanea installata nella regione epicentrale (Moretti et al. , 2016), dal 14 agosto 2016 al 31 agosto 2018 e analizzati manualmente dagli analisti del Bollettino Sismico Italiano (BSI, http://cnt.rm.ingv.it/bsi) . Le