GNGTS 2024 - Atti del 42° Convegno Nazionale

Session 1.1 GNGTS 2024 Seismic sequence of 2009 and 2016. The disastrous earthquakes of 2009 and 2016 both involved central Italy, afectng the Abruzzo and Lazio-Umbria regions, respectvely. The 2009 seismic sequence recorded a mainshock of Mw 6.3 (Chiarabba et al, 2009), with approximately 64k afershocks (Valoroso et al, 2013). The arrangement of the afershocks suggests that, beside the actvaton of the UAFS - which generated the main mainshock and the greatest number of afershocks - the nearby GSFS fault system was also involved, without evidence of coseismic rupture along the fault planes of the GSFS (Galli et al, 2022, Fig. 1). Diferently, the 2016 seismic sequence was produced frst by the joint actvaton of the MVFS and the Laga Fault System on 24 August, Mw 6.2 (RCMT, 2016) and then only by the MVFS, frst in the northern sector, 26 October, Mw 6.1 (RCMT, 2016) and later entrely on 30 October Mw 6.6 (RCMT, 2016). Following the 30 October event, ~2 km of coseismic ruptures were observed along the main fault planes of the NFS (Galderisi and Galli, 2019; 2020), although no afershocks were observed along the NFS (Improta et al, 2019; Galderisi and Galli, 2020).