GNGTS 2017 - 36° Convegno Nazionale

GNGTS 2017 S essione 1.1 69 carried out in Friuli. The study area belongs to the eastern corner of north-eastern Italy, where the SSE-verging, WSW-ENE trending fold and thrust-belt of the eastern Southern Alps (Middle Miocene – Present) joints the NW-SE trending dextral strike-slip fault systems (Pliocene – Present) of western Slovenia (Fig. 1). Medium to high historical and instrumental seismicity scattered along the Friuli area testifies active deformation (Locati et al. , 2016). Some M>6 earthquakes caused widespread damage in Friuli and bordering regions: the 1348 (January 25, Carnia earthquake: Imax: 9, Mw: 6,6), the 1511 (March 26, Friuli-Slovenia earthquake: Imax: 9; Mw: 6,3) the 1873 (June, 29, Alpago earthquake. Imax: 9-10; Mw: 6,3), the 1936 (October 18, Cansiglio earthquake: Imax: 9; Mw: 6,1), the 1976 (Friuli earthquakes on May, 6 and September,15: Imax: 10, Mw: 6.45 and Imax: 8-9, Mw: 5,9 respectively). Inordertolocatepaleoseismologicaltrenches,detailedsurficialgeologicalandmorphotectonic surveys were carried out. Moreover when possible, accurate analysis of seismic industrial lines was gathered to the surface data. These preliminary analyses were often joined to integrated geophysical investigations as electrical resistivity tomography, seismic refraction and reflection, Ground Penetrating Radar (GPR), passive seismic (HVSR, ReMi), and MASW. On these bases we selected three different sites where digging paleoseismological trenches: the first investigated the Caneva – Col Longone tectonic system (Western Friuli); the second the Maniago thrust (Western Carnic Prealps) and the third was located along the Colle Villano thrust near the Italian-Slovenia border region (Fig. 1). All the investigated trenches-sites indicated active tectonic deformations of historical age, suggesting high seismic hazard. References Locati M., Camassi R., Rovida A., Ercolani E., Bernardini F., Castelli V., Caracciolo C.H., Tertulliani A., Rossi A., Azzaro R., D’Amico S., Conte S. and Rocchetti E.; 2016: DBMI15, the 2015 version of the Italian Macroseismic Database. Istituto Nazionale di Geofisica e Vulcanologia. doi :http://doi.org/10.6092/INGV.IT-DBMI15. Zanferrari A., Masetti D., Monegato G. and Poli M.E.; 2013: Geological map and explanatory notes of the Geological Map of Italy at the scale 1:50.000: Sheet 049 “Gemona del Friuli”. ISPRA - Servizio Geologico d’Italia-Regione Autonoma Friuli Venezia Giulia, 262 pp. http://www.isprambiente.gov.it/Media/carg/friuli.html SEISMICITY, DAMAGE CLASSIFICATION AND VULNERABILITY FACTORS IN AMATRICE AFTER AUGUST 24, 2016 EARTHQUAKES F. Sabetta, G. Fiorentino, A. Forte, E. Pagano, C. Baggio, D. Lavorato, C. Nuti, S. Santini Department of Architecture, Roma3 University, Roma, Italy The seismic events which hit central Italy on August 24, October 26 and October 30, 2016 have caused casualties and major damage mostly to buildings and architectural heritage of the Italian regions of Abruzzo, Lazio, Marche and Umbria. The impact of the two earthquakes of August 24 2016 was highly destructive: there were 298 victims, 386 injured, about 5000 homeless, and the historical center of Amatrice suffered a great number of partial and total collapses (Italian Department of Civil Protection 2017). The Amatrice seismic sequence has been recorded by a large number of strong-motion stations of the Italian accelerometric network (RAN http://ran.protezionecivile.it/IT/index.php) . Tab. 1 shows, besides the number of recordings for the events with Mw ≥ 5.5 (http://esm.mi.ingv.it, Luzi et al. , 2016), the main parameters of the selected events. The PGAvalues of the records obtained by the RAN stations have been compared with three different Ground Motion Prediction Equations (GMPE): SP96 (Sabetta and Pugliese 1996), AK14 (Akkar et al., 2014) and CF08 (Cauzzi and Faccioli, 2008). The recorded PGAs are