GNGTS 2016 - Atti del 35° Convegno Nazionale

GNGTS 2016 S essione 2.2 409 the southeastern corner of the Matese lake intramontane basin and fall in an area of about 2 km 2 . The hypocentre depth is less constrained and ranges from 12 km (D’Amico et al. , 2014) to 20 km (ISIDE, http://iside.rm.ingv.it) . Seismically induced ground effects of the Mw = 5.0, 2013 Matese earthquake have been identified through the combination of interviews with local people and local municipality officers, local newspapers and web reports and field work (Valente et al. , 2015b). Most of such activities have been carried out from February 2014 to December 2014. A large support to the collection of information has been provided by technical offices of the local municipalities, who provided us with large amounts of both internal and official reports on damages induced by seismic shacking on roads, aqueducts and private properties. Such information has been used to locate and characterise the possible causative ground effects, which have been directly verified either in the field or by pictures taken by the interviewers or by web reports. Identified environmental earthquake effects include a flame, gas flux, surface ruptures, landslides and hydrological variations (Fig. 1). All of such effects affected an area of about 90 km 2 and have been recognized up to 8.5 km away from the epicentre location reported in the ISIDE database. The mt. Airola coseismic rupture. A coseismic rupture has been recognised based on information by local people, who noticed the rupture the day after the 29 December main shock in an intramontane basin (the Mt. Airola basin) located at 1200 m a.s.l. in the Matese ridge top surface, at a distance of about 4.5 km to the SW of the earthquake epicentre and 3.5 km to the NE of San Potito Sannitico village. The coseismic rupture affects the northeastern slope of a subdued, fault-bounded, WNW-ESE elongated carbonate ridge that bounds the Mt. Airola basin to the SW. The rupture is striking N120, facing NE, and is up to 30 cm high and around 50 m long. At the toe of the slope where the rupture occurred, an almost 1 m high scarp also striking N120, facing NE and about 100 meters long is present. With the aim of reconstructing the surface and subsurface geological setting of the Mt. Airola basin, and constraining the geological and geometrical features of the 29 December coseismic rupture, we have carried out a detail scale geological and geomorphological survey, Fig. 1 – Map of the seismic induced environmental effects related to the December 2013 - January 2014 Matese seismic sequence. Black ellipse indicates the total area affected by ground effects, which results to be of about 90 km 2 .