GNGTS 2018 - 37° Convegno Nazionale

GNGTS 2018 S essione 1.1 15 Gruppo di Lavoro CSTI; 2005: Catalogo Strumentale dei Terremoti Italiani dal 1981 al 1996 (Versione 1.1), <http:// gaspy.df.unibo.it/paolo/gndt/Versione1_1/Leggimi.htm > Lavecchia G., Brozzetti F., Barchi M., Menichetti M. and Keller J. V.; 1994: S eismotectonic zoning in east-central Italy deduced from an analysis of the Neogene to present deformations and related stress fields. GSA Bulletin, 106 , 9, 1107-1120. Lomax A., Virieux J., Volant P. and Berge-Thierry C.; 2000: Probabilistic earthquake location in 3D and layered models: introduction of a Metropolis-Gibbs method and comparison with linear locations. InAdvances in Seismic Event Location (pp. 101-134). Kluwer, Amsterdam: eds Thurber C.H & Rabinowitz NonLinLoc software, version 6.00, <http://alomax.free.fr/nlloc> Monachesi G., Castelli V. and Vasapollo N.; 1991: Historical earthquakes in central Italy: Case history in the Marche area . Tectonophysics, 193 , 95-107. Riguzzi F., Tertulliani A. and Gasparini C.; 1989: S tudy of Seismic Sequence of Porto San Giorgio (Marche) - 3 July 1987 . Il nuovo cimento, 12 , 4, 453-466. Rovida A., Locati M., Camassi R., Lolli B., Gasperini P. (eds); 2016: C PTI15, 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. Scognamiglio L., Tinti E. and Michelini A.; 2009: Real-Time Determination of Seismic Moment Tensor for the Italian Region. Bulletin of the Seismological Society of America, 9, 4, 2223–2242, doi: 10.1785/0120080104. EVIDENCE OF ROMAN EARTHQUAKE SURFACE FAULTING AT SANTA VENERA AL POZZO (CATANIA, SOUTHERN ITALY): A PROBABLE SEISMIC EVENT IN 251 AD? C. Bottari 1 , P. Capizzi 2 , D. Cavallaro 3 , S. Giammanco 3 , R. Martorana 2 , S. Scudero 4 , F. Sortino 5 , P. Bonfanti 3 1 Istituto Nazionale di Geofisica e Vulcanologia, Roma 2 2 Università di Palermo, Dipartimento di scienze della Terra e del Mare 3 Istituto Nazionale di Geofisica e Vulcanologia, OE 4 Istituto Nazionale di Geofisica e Vulcanologia, ONT 5 Istituto Nazionale di Geofisica e Vulcanologia, Roma1 Introduction. The record of historical seismicity of Catania and its neighbourhood during the first millenniumAD is largely incomplete due to the scarcity of sources reporting information on earthquake damage. Although numerous historical sources provide plentiful description of past Etnean eruptions affecting the Catania area, only a vague picture of the local seismicity is available for ancient times. This study provides new insights on seismic history of Catania, which was struck by large earthquakes during its recent history (i.e. 1542, 1693, and 1818 earthquakes). During the first millennium, the only documented earthquake occurred in 251 AD, a year before of the big Etna eruption of 252 AD (Guidoboni et al. , 2014). This earthquake left well-visible traces in the archaeological site of Santa Venera al Pozzo (Catania), which was continuously inhabited since 3000 BC, due to the presence of sulphur warm water springs. The buildings uncovered by archaeologists are a podium of a Roman temple; a thermal bath provided with five different pools at least; a Roman rural Villa; and a church of Byzantine age. The site is located on the eastern flank of Mt. Etna volcano, where seismic activity has often caused significant damage, even though localized, especially when associated with remarkable flank eruptions. Evidence of Roman age faulting has been observed in the archaeological site, which is clearly affected by a set of sharp fractures generating an overall ~ 4 m wide fracture zone. The main fracture extends for about 40 m with a ~N-S direction, offsetting the foundations of a podium, some pools and minor walls. It shows an extensional displacement of up to 5-8 cm and a right-lateral component with an offset of up to 4 cm. Fracture zones related to normal faults are quite common in the lower eastern flank of Mt. Etna (Azzaro et al. , 2012). Some of these structures are also characterized by anomalous diffuse CO 2 emissions from the soil (Giammanco and Bonfanti, 2009). The archaeological site is placed in proximity of one of