GNGTS 2016 - Atti del 35° Convegno Nazionale

GNGTS 2016 S essione A matrice 55 Marzocchi, W., Amato A., Akinci A., Chiarabba C., Lombardi A.M., Pantosti D. and Boschi E.; 2012: A ten-year earthquake occurrence model for Italy . Bull. Seism. Soc. Am., 102, 1195-1213. Marzocchi W, Lombardi A.M. and Casarotti E.; 2014: The Establishment of an Operational Earthquake Forecasting System in Italy . Seism. Reaserch Lett., 85, 961-969, doi: 10.1785/0220130219. Ogata, Y.; 1998: Space-Time Point-Process models for Earthquake Occurrences . Ann Inst Stat Math, 50, 379-402. RovidaA., Locati M., Camassi R., Lolli B., Gasperini P.; 2016: CPTI15, the 2015 version of the Parametric Catalogue of Italian Earthquakes . Istituto Nazionale di Geofisica e Vulcanologia. doi :http://doi.org/10.6092/INGV.IT- CPTI15 Landslides triggered by the August 24, 2016 (Mw 6.0) Amatrice earthquake (Italy): data survey and inventorying S. Martino 1 , F. Bozzano 1 , P. Caporossi 1 , M. Della Seta 1 , C. Esposito 1 , A. Fantini 1,2 , M. Fiorucci 1 , R. Iannucci 1 , G.M. Marmoni 1 , P. Mazzanti 1,3 , S. Moretto 1 , S. Rivellino 1 , R.W. Romeo 4 , P. Sarandrea 1,2 , F. Troiani 1 , C. Varone 1 1 Dpt. Earth Sciences and Research Center for the Geological Risks (CERI), Sapienza University, Rome, Italy 2 Tecnostudi Ambiente Srl, Roma, Italy 3 NHAZCA S.r.l., spin-off Sapienza University, Rome, Italy 4 Department of Earth Sciences, Life and Environment, University “Carlo Bo”, Urbino, Italy Introduction. OnAugust 24, 2016 a strong earthquake (M w 6.0 – 42.714°N 13.172°E) struck central Apennines (Italy) at 3.36 a.m. (local time), starting a seismic sequence characterized by a M w 5.4 and thousands of M w <5 aftershocks. The seismic sequence caused the complete destruction of the historical towns of Amatrice, Arquata del Tronto, Accumoli and Pescara del Tronto but also significant damages to several towns and villages within 20 km from the epicenter. Since the first hours after the mainshock a Working Group coordinated by the Research Centre on Geological Risks (CERI) of the Sapienza University of Rome operated in the field to survey the ground effects induced by the earthquake. More than one hundred landslides have been surveyed. These events include mainly rock falls and rock slides, which are distributed within a distance of about 40 km from the mainshock epicenter. Several landslides involved roads but no severe damages were generally produced. Field surveys. The field surveys were planned starting from the first hours after the M w 6.0 earthquake occurrence and were carried out up to 50 km far from the epicenter for 10 days, until the first rainfalls occurred, which triggered further secondary ground effects. These last ones were not inventoried since they were not considered as properly triggered by the earthquake shaking. The surveying criteria were focused on distinguishing the most recent landslides with respect to older ones, as well as to provide a high reliability of the earthquake trigger interpretation. In this regard, in case of rockslides the following evidence has been collected: - clearly visible source areas of rock falls or slides: clean surfaces, not weathered scarps; - clearly visible rock mass debris: clean debris, not weathered blocks, blocks over vegetation; - clearly visible tracks of rolled blocks; - detectable impact point of blocks. In case of debris slides the following evidence has been collected: - remobilized debris: chaotic deposit overlapping the older accumulation surface; - evidence of perimetral ground cracks (due to the detachment of debris above the bedrock); - evidence of open ground cracks within debris with fresh vegetation cover.