Abstract
AbstractWe integrate paleoseismic data sets along the Mt. Vettore‐Mt. Bove normal fault system rupturing at the surface in the 30 October 2016 Norcia earthquake. Through the analysis of new trenches from this work and a review of the preexisting data, we correlate events among trench sites along antithetic and synthetic fault splays. We recognize seven M 6.5, 2016 Norcia‐type (or larger) surface‐faulting events in the last ~22 kyr, including 2016. Before 2016, one event occurred in the past two millennia (260–575 CE) and possibly corresponds to the event damaging Rome in 443 or 484/508 CE. Three previous events occurred between 10590 and 415 BCE, whereas the two oldest ones date between 19820 and 16540 BCE. The average recurrence time is 3,360–3,640 years for the last ~22 kyr and 1,220–1,970 years for the last ~4 kyr. We infer a minimum dip‐slip rate of 0.26–0.38 mm/year on the master fault in the central portion of the Mt. Vettore–Mt. Bove normal fault system and a dip‐slip rate of at least 0.10 mm/year on the southernmost portion. We infer a Middle–Late Pleistocene inception of the long‐term scarp of the investigated splays. The along‐strike variation of slip rates well reproduces the trend of the 2016 surface slip; thus, the time window exposed in the trenches is representative for the present fault activity. Based on trenching data, different earthquake rupture scenarios should be also considered for local hazard assessment.
Highlights
The 2016 earthquake sequence in the central Apennines took the lives of 299 people, severely injured 365 others, and caused severe damage to structures and infrastructures and to a rich cultural heritage, resulting in 50,000 displaced persons and more than 10B€ losses
The surface rupturing 2016 Norcia earthquake represents the chance to extend the earthquake history of the VBFS, refine the slip rate and other parameters that are important to assess the seismic hazard in this part of the Apennines
The 2016 earthquake sequence in the central Apennines (Figure 1) started on 24 August with a Mw 6.1 mainshock, which was followed by a Mw 5.9 mainshock on 26 October and a Mw 6.5 mainshock on 30 October 2016
Summary
The 2016 earthquake sequence in the central Apennines (main events on 24 August Mw 6.1, 26 October Mw 5.9, and 30 October Mw 6.5; Figure 1) took the lives of 299 people, severely injured 365 others, and caused severe damage to structures and infrastructures and to a rich cultural heritage, resulting in 50,000 displaced persons and more than 10B€ losses (http://www.protezionecivile.gov.it/risk-activities/seismic-risk/emergencies/central-italy-2016). The surface rupturing 2016 Norcia earthquake represents the chance to extend the earthquake history of the VBFS, refine the slip rate and other parameters that are important to assess the seismic hazard in this part of the Apennines We took this opportunity and investigated new trenches along two distinct segments of the VBFS. We address four primary topics: (1) the presentation of our paleoseismic record on the VBFS, discussing selection of the trench sites, trench observations, and earthquake timing; (2) the integration of our results with the multiple fault-trench investigations from other authors to reduce uncertainties in earthquake chronologies; (3) the estimation of slip rate and average earthquake recurrence, fondamental components of our understanding of the VBFS activity; and (4) the implications of our synthesis of VBFS paleoseismic data for the broad understanding of the seismogenic source within the Apennines tectonic frame, including earthquake rupture models
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
