GNGTS 2016 - Atti del 35° Convegno Nazionale

GNGTS 2016 S essione A matrice 87 hypocenter, the rupture stops near Amatrice. On the opposite end of the rupture, the slip for the double-fault model does not show significant values north of the mid Castelluccio Plain, while for the single fault model the slip continues a little further to the north. The two larger slip concentrations are located at depths of –6 km in the northern area (for both models), and of –4 km underneath Accumoli. Depending on the model, the slip values are approximately equal to zero at depths shallower than 1.5-3 km (to the north) or 700 m (to the south). Slip values of few cm for the most superficial patches of the faults are modelled in an uneven way. The Amatrice event has once more demonstrated the maturity of InSAR data monitoring in providing scientific support for operational crisis management. Only 20 hours after the mainshock the first source model based only on the ALOS 2 interferogram, was generated. This model, and its successive updates integrating more InSAR interferograms and eventually also GPS data, were crucial for the source identification, and supported the National Civil Protection authorities in their analysis of the situational awareness. The timely results were also possible thanks to the availability of multiple SAR instruments, which presently allows to reduce the post-event revisit time with any sensor, to 1-2 days on average. The remaining issue to maintain a high monitoring capacity for these applications at the global scale is the need of a continuous, long term background mission over the seismically active areas, which is presently in place only for Sentinel-1 and ALOS 2. Acknowledgements. We thankASI for providing COSMO-SkyMed data, ESAfor Sentinel1 data and JAXAforALOS- 2 data. We also thank the SARMAP team for the fruitful collaboration, in particular Dr. P. Riccardi for his support. References AMA_LOC Working Group, 2016. AMATRICE 2016 aftershocks RE-location catalogue (V1.0 – from 20160824 01:41 to 20160831 12:19), DOI: 10.5281/zenodo.61404 Gruppo di lavoro IREA-CNR & INGV, 2016 Sequenza sismica di Amatrice: risultati iniziali delle analisi interferometriche satellitari, DOI: 10.5281/zenodo.60938 INGV Working Group “GPS Geodesy (GPS data and data analysis center)”, 2016. Preliminary co-seismic displacements for the August 24, 2016 ML6, Amatrice (central Italy) earthquake from the analysis of continuous GPS stations, DOI: 10.5281/zenodo.61355. Michele M., Di Stefano R., Chiaraluce L., Cattaneo M., De Gori P., Monachesi G., Latorre D., Marzorati S., Valoroso L., Ladina C., Chiarabba C., Lauciani V., Fares M., The Amatrice 2016 seismic sequence: a preliminary look to the mainshock and aftershocks distribution , Annals of Geophisics Fast Track, in preparation. Okada Y. (1985). Surface deformation due to shear and tensile faults in a half-space, Bull. Seism. Soc. Am. 75, 1135- 1154. Fig. 1 – Modelling results. Slip distribution retrieved from the InSAR and GPS data of the Amatrice earthquake using the single fault model (left) and the double fault model (right). Hypocenter relocation from Michele et al. (2016).