GPS observations of coseismic deformation following the 2016, August 24, Mw 6 Amatrice earthquake (central Italy): data, analysis and preliminary fault model

D Cheloni ,Piera Gambino Piera Gambino,Luigi Abruzzese Luigi Abruzzese,Angelo Castagnozzi Angelo Castagnozzi,Felice Minichiello Felice Minichiello,Enrico Serpelloni Enrico Serpelloni,Gianpaolo Cecere Gianpaolo Cecere,Federica Riguzzi Federica Riguzzi,Stefano Calcaterra Stefano Calcaterra,Vincenzo Sepe Vincenzo Sepe,Marco Anzidei Marco Anzidei,Vincenzo Cardinale Vincenzo Cardinale,Luigi Zarrilli Luigi Zarrilli,Franco Migliari Franco Migliari,Grazia Pietrantonio Grazia Pietrantonio,Roberta Giuliani Roberta Giuliani,Luigi Falco Luigi Falco,Angelo Massucci Angelo Massucci,Giovanni De Luca Giovanni De Luca,A Esposito ,Ciriaco D’ambrosio ,G Selvaggi ,A Galvani ,Antonino Memmolo ,R Devoti ,A Avallone ,M Mattone ,A Cavaliere ,N D’agostino

doi:10.4401/ag-7269

Abstract

<p>We used continuous Global Positioning System (GPS) measurements to infer the fault geometry and the amount of coseismic slip associated to the August 24, 2016 Mw 6 Amatrice earthquake. We realized a three dimensional coseismic displacement field by combining different geodetic solutions generated by three independent analyses of the raw GPS observations. The coseismic deformation field described in this work aims at representing a consensus solution that minimizes the systematic biases potentially present in the individual geodetic solutions. Because of the limited number of stations available we modeled the measured coseismic displacements using a uniform slip model, deriving the geometry and kinematics of the causative fault, finding good agreement between our geodetically derived fault plane and other seismological and geological observations. <strong></strong></p>

Highlights

AMw 6.0 (Ml 6.0) earthquake struck the Central Apennines between the towns of Norcia and Amatrice on August 24, 2016, at 03:36
In this work we describe the Global Positioning System (GPS) data used to study the coseismic deformation related to the August 24 mainshock and provide a preliminary model of the coseismic source inverted from a “consensus” GPS coseismic displacement field, obtained following the procedures described in Devoti (2012) and used to study the 2012 Emilia seismic sequence (Serpelloni et al, 2012)
As shown during the Emilia 2012 earthquake sequence, the availability of, even sparse, GPS stations continuously recording across moderate magnitude earthquakes can provide reliable constraints on the geometry and kinematics of the causative fault

Summary

INTRODUCTION

AMw 6.0 (Ml 6.0) earthquake struck the Central Apennines between the towns of Norcia and Amatrice on August 24, 2016, at 03:36 (local time). The focal mechanisms of the mainshock and of the larger aftershocks (http://www.bo.ingv.it/RCMT and http://cnt.rm.ingv.it/tdmt) consistently show a SW-NE oriented extension with chainparallel oriented nodal planes, in agreement with the SW-NE extension measured by GPS stations in this sector of the Apennines (e.g., Galvani et al, 2012 and references therein). This earthquake occurred within the belt of high geodetic deformation rates that characterizes the Apennine chain (e.g., D’Agostino, 2014) and where several continuous Global Navigation Satellite System (GNSS) networks, managed by private and public companies and institutions, are operating.

AVAILABLE GPS DATA

GPS DATA ANALYSIS

COSEISMIC DISPLACEMENTS AND FAUT MODEL

CONCLUSIONS