Overview of the seismic hazard in the Sicily channel archipelagos

Abstract

A joint Italo–Maltese research project (Costituzione di un Sistema Integrato di Protezione Civile Transfrontaliero Italo–Maltese, SIMIT) was financially supported by the European community. One of the aims of SIMIT was to improve the geological and geophysical information in Lampedusa and in Malta and ultimately to mitigate natural hazards. Although this region lies on the Sicily Channel Rift Zone, a seismically active domain of Central Mediterranean, the knowledge about seismotectonic and seismic hazard is not satisfactory. At present, seismic hazard assessment (SHA) for Italy (MPS Working Group, 2004), Tunisia (Ksentini and Romdhane, 2014) and more generally for whole European areas (Giardini et al., 2013) do exist, whereas no specific SHA for the Sicily channel archipelagos are available. The Sicily Channel appears to be a region of moderate seismic activity, with the seismicity mainly located in the surrounding areas (Fig. 1). For the Malta archipelago a first catalogue, listing historical and felt earthquakes, was made by Galea (2007), whereas the Database Macrosismico Italiano (DBMI11; Locatiet al., 2011) does not list any data as regards earthquakes felt in Lampedusa. For this reason, in the present study, a theoretical seismic history was derived (Fig. 2) for Lampedusa and Malta, using the European–Mediterranean Earthquake Catalogue (EMEC) (Grünthal and Wahlström, 2012) and the attenuation relationship for macroseismic intensity data by Pasolini et al. (2008). The two study areas do not appear to have been affected by strong earthquakes occurring in the Sicily channel, but they were somehow struck by major earthquakes occurring in the surrounding area.