We present a 1:25,000 scale map of the coseismic surface ruptures following the 30 October 2016 M_w 6.5 Norcia normal-faulting earthquake, central Italy. Detailed rupture mapping is based on almost 11,000 oblique photographs taken from helicopter flights, that has been verified and integrated with field data (>7000 measurements). Thanks to the common efforts of the Open EMERGEO Working Group (130 people, 25 research institutions and universities from Europe), we were able to document a complex surface faulting pattern with a dominant strike of N135°-160° (SW-dipping) and a subordinate strike of N320°-345° (NE-dipping) along about 28 km of the active Mt. Vettore–Mt. Bove fault system. Geometric and kinematic characteristics of the rupture were observed and recorded along closely spaced, parallel or subparallel, overlapping or step-like synthetic and antithetic fault splays of the activated fault systems, comprising a total surface rupture length of approximately 46 km when all ruptures were considered.

We investigate the ground deformation and source geometry of the 2016 Amatrice earthquake (Central Italy) by exploiting ALOS2 and Sentinel‐1 coseismic differential interferometric synthetic aperture radar (DInSAR) measurements. They reveal two NNW‐SSE striking surface deformation lobes, which could be the effect of two distinct faults or the rupture propagation of a single fault. We examine both cases through a single and a double dislocation planar source. Subsequently, we extend our analysis by applying a 3‐D finite elements approach jointly exploiting DInSAR measurements and an independent, structurally constrained, 3‐D fault model. This model is based on a double fault system including the two northern Gorzano and Redentore‐Vettoretto faults (NGF and RVF) which merge into a single WSW dipping fault surface at the hypocentral depth (8 km). The retrieved best fit coseismic surface deformation pattern well supports the exploited structural model. The maximum displacements occur at 5–7 km depth, reaching 90 cm on the RVF footwall and 80 cm on the NGF hanging wall. The von Mises stress field confirms the retrieved seismogenic scenario.

We focus on the coseismic surface faulting exposed along the Mt. Vettore‐Mt. Bove fault system (VBF, central Italy), that activated during the 24 August 2016, Amatrice earthquake (M_w6.0) and soon after reactivated during the 26 October Visso (M_w5.9) and 30 October Norcia events (M_w6.5 mainshock). We systematically recognized the coseismic surface ruptures of the aforesaid earthquakes, which document the repeated surface faulting on the same seismogenic structure in close temporal succession. We surveyed 1,747 evidence of coseismic ruptures, 325 fault plane attitudes along the Vettoretto‐Redentore segment, and over 4,000 data along the entire VBF that were organized in a GIS‐database. This data set allowed us to estimate the coseismic surface rupture length (SRL), maximum (MD) and average (AD) displacement associated with the M_w6.0 and M_w6.5 events. We found that the SRL and MD associated with the former are respectively 5.8 km and 28.5 cm and AD reaches 12.7 cm. For the mainshock, the values of SRL ≥ 22 km and MD = 222 cm were measured. The cumulative, post‐30 October parameters are SRL = 30 km, MD = 240 cm, AD = 36 cm. Despite that the MD of the M_w6.0 event differs by ~1 order of magnitude respect to the mainshock MD, the two slip profiles display a similar multiscale sinuosity showing a significant control of the long‐term fault segmentation on the coseismic rupturing. Comparing the obtained coseismic parameters with literature global earthquakes data highlights some peculiarities of the 2016 central Italy surface rupture pattern, which suggest caution in applying empirical relationships to highly segmented seismogenic faults.