The Campotosto Seismic Gap in Between the 2009 and 2016–2017 Seismic Sequences of Central Italy and the Role of Inherited Lithospheric Faults in Regional Seismotectonic Settings

Abstract

The 2016-2017 seismic sequence, in central Italy, was caused by the Mt. Vettore-Mt. Bove active fault system, which generated three mainshocks, the largest one of M w 6.

Testing Different Tectonic Models for the Source of the Mw 6.5, 30 October 2016, Norcia Earthquake (Central Italy): A Youthful Normal Fault, or Negative Inversion of an Old Thrust?

“…As extension is a somewhat recent occurrence along the most external portion of the Apennines, partial or total reuse of inherited thrust faults is indeed a viable scenario. In this respect, the rather shallow dip suggested by the majority of published studies for the main earthquake causative fault must be considered carefully, because it may imply the inherited structures played a prominent role, as already suggested by other investigators (e.g., Bonini, Maesano, et al, ; Chiarabba et al, ; Falcucci et al, ; Scognamiglio et al, ).…”

“…Although the 2016–2017 central Italy earthquakes occurred 2 years ago, they have already been investigated by numerous scientists worldwide, probably due to the severity of the damage they caused, to their source complexity, and to the spectacular surface breaks generated by the largest shocks (e.g., Bonini, Maesano, et al, ; Cheloni et al, ; Chiaraluce et al, ; Civico et al, ; Doglioni et al, ; Falcucci et al, ; Pizzi et al, ; Porreca et al, ; Pucci et al, ; Walters et al, ; Xu et al, ; Zhong et al, ; see also references in Tables and ). Most activated surface faults exhibit a steep dip angle (e.g., Villani et al, ), although aftershock patterns, focal mechanisms, and geodetic data analyses all suggest a rather low dip for the causative fault of the Norcia mainshock (40° on average; see Table ).…”

Tectonics Inversions, Fault Segmentation, and Triggering Mechanisms in the Central Apennines Normal Fault System: Insights From High‐Resolution Velocity Models

“…The geological evidences of the MLGf segment have been investigated by previous works (Bigi et al, ; Boncio, Lavecchia, Milana, & Rozzi, ; Boncio, Lavecchia, & Pace, ; Falcucci et al, ; Galadini & Galli, ; Lavecchia et al, ). This fault segment was also the site of several moderate‐magnitude earthquakes ( Mw < 5.5) during the 2009 and 2016–2018 seismic sequences (see Figure ).…”

Coseismic Throw Variation Across Along‐Strike Bends on Active Normal Faults: Implications for Displacement Versus Length Scaling of Earthquake Ruptures

“…It is unclear because on the 30 October 2016, before field surveys of the 26 October earthquakes, a M w 6.5 earthquake ruptured the total length of the Mt. Vettore fault, rerupturing locations that slipped in the 24 August 2016 earthquake and perhaps those on the 26 October (see Figures , , and ; Calderoni et al, ; Cheloni et al, ; Chiaraluce et al, ; Civico et al, ; Falcucci et al, ; Ferrario & Livio, ; Lavecchia et al, ; Mildon et al, ; Pavlides et al, ; Perouse et al, ; Pizzi et al, ; Porreca et al, ; Scognamiglio et al, ; Verdecchia et al, ; Villani, Civico, et al, ; Villani, Pucci, et al, ; Walters et al, ). Meter‐scale offset across surface ruptures was measured with near‐field 1‐Hz global navigation satellite system for the 30 October ruptures, revealing that the ruptures formed within 2–4 s and, before peak ground acceleration, supporting the primary tectonic origin of the ruptures (Wilkinson et al, ; Figure ).…”