资源环境科技发展态势分析平台

We investigate the rupture process of the 2016, M(w)6.1 Amatrice earthquake, the first shock of a seismic sequence characterized by three damaging earthquakes occurred in central Italy between August and October. We jointly invert strong motion, High-Rate GPS data, GPS, and DInSAR displacements and we adopt ad hoc velocity profiles of the crust below each station. The retrieved source model reveals a high degree of complexity, characterized by a prominent bilateral rupture with low slip at the hypocenter, two well-separated slip patches and a rupture front accelerating when breaking the largest patch. The rupture of the main asperity features a slip-velocity pulse that is impeded ahead of its current direction and splits into two pulses. In this fault section we find clues of structural and rheological control of the rupture propagation due to the fault system segmentation.

Plain Language Summary This work provides relevant information for Seismology community and the results may have important implications for earthquake hazard assessment. Indeed, indication of the role played by the fault segmentation in limiting the size of single earthquake in Central Italy is gained.In particular, we retrieve the source process of the 2016 Amatrice, central Italy, earthquake by jointly invert for a comprehensive dataset (strong motion, HRcGPS, GPS and DInSAR measurements).The main outcome of our study is that the rupture process has been characterized by a strong geometrical and rheological control due to the presence of important segmentation of the thrust fault system, distinctive of the central Apennines. Indeed, our results provide a complete description of the rupture propagation and inhibition due to the presence of inherited tectonic structures, which role in the seismic sequence evolution could be due to the favourable or unfavourable orientation within the active stress regime geometries and rheological variations between fault blocks. We believe that, in this context, our results are of potential impact for a broad readership because the interaction between new and/or inherited faults, strongly influences the fault segmentation and fault lengths, determining the maximum magnitude of individual earthquakes and consequently the seismic hazard.