GNGTS 2017 - 36° Convegno Nazionale

18 GNGTS 2017 S essione 1.1 BOLLETTINO SISMICO ITALIANO: ANALISYS OF EARLY AFTERSHOCKS OF THE 2016 Mw 6.0 AMATRICE, Mw 5.9 VISSO AND Mw 6.5 NORCIA EARTHQUAKES IN CENTRAL ITALY B. Castello e Gruppo di Lavoro Bollettino Sismico Italiano (A. Nardi, A. Marchetti, F.M. Mele, A. Rossi P. Battelli, M. Berardi, C. Castellano, C. Melorio, G. Modica, M. Pirro, S. Spadoni, L. Arcoraci, G. Lozzi, A. Battelli, C. Thermes, M.G. Ciaccio, B. Castello, N. Pagliuca, A. Lisi, L. Pizzino, P. Baccheschi, A. Sciarra, A. Bono, C. Marcocci, V. Lauciani, A. Mandiello, S. Pintore, M. Quintiliani, A. Frepoli, D. Latorre, D. Cheloni, A.M. Lombardi, M. Vallocchia, B. Cantucci, L. Colini, S. Pinzi, L. Scognamiglio, A. Basili, F. Villani, G. D’Addezio, T. Sgroi, A. Smedile, C. Montuori, R. Tardini, R. Tozzi, S. Monna, M.T. Mariucci, R. Di Maro, L. Margheriti) Istituto Nazionale di Geofisica e Vulcanologia, INGV The Amatrice-Visso-Norcia seismic sequence is the most important of the last 30 years in Italy. The seismic sequence started on 24August, 2016 and still is ongoing in central Apennines. At the end of February 2017 more than 57,000 events were located, 80,000 events up to the end of September 2017 (Fig. 1). The mainshocks of the sequence occurred on 24August 2016 (M w 6.0 and M w 5.4), 26 October 2016 (M w 5.4 and M w 5.9), 30 October 2016 (M w 6.5), 18 January 2017 (four earthquakes M w ≥ 5.0). In this seismic sequence, all the waveforms recorded by temporary stations deployed by the SISMIKO emergency group (stations T12 ** ; Moretti et al., 2016) where available in real- time at the surveillance room of INGV. Because of the high level of seismicity and the dense seismic network installed in the region, more than 150 events per day were located at the end of February 2017; still 60 events per day were located up to the end of August 2017. Fig. 1 - Map of the seismicity of the Amatrice-Visso-Norcia seismic sequence (AVN.s.s) from August 24 th , 2016 to September 30 th , 2017.