GNGTS 2014 - Atti del 33° Convegno Nazionale

GNGTS 2014 S essione 1.1 43 among which the Lamezia-Catanzaro Fault Zone had controlled the Catanzaro Trough from the Middle Miocene up to Middle Pleistocene. Geophysical studies, especially seismic anomalies (Barberi et al. , 2004), allow to identify these transcurrent regional fault systems, which are considered by Del Ben et al. (2008) as two tectonic elements accomodating movements between northern and southern sector of Calabrian Arc. The structural framework of the Calabrian belt is further complicated by the activation of recent longitudinal fault systems, namely the N–S and NE–SW striking faults that are parallel to the mountain system. Considering the high structural complexity and the currently active tectonics, the Calabria is one of the Mediterranean regions which present the highest probability of occurrence of major earthquakes (Rotondi, 2010). The distribution of crustal seismicity shows that most of the events which have occurred in the study area are located in the hanging-walls of Plio- Pleistocenic normal faults. The largest events reached magnitude of around Mw 7, as during the sequence of February-March 1783, in the S. Eufemia 1905 earthquake, and during the sequence of March-June 1638. The aim of this work is to define Plio-Quaternary evolution of central Calabrian Arc and, if possible, to evaluate the seismogenic potential of this area. This purpose is supported, essentially, by geo-structural data analysis and geomorphological observations. Geological setting. The Catanzaro Trough is infilled by a Neogene-Quaternary sedimentary succession separated by major unconformities. This succession overlies the igneous- metamorphic basement, which is widely outcropping in the Serre and the Sila massif, both located in the central Calabrian Arc (Fig. 2). Basically, the sedimentary sequence documents the pulsating displacement of the Calabrian block towards the southeast and the opening of the Tyrrhenian back-arc basin during the last Fig. 1 – Geological and structural map of study area.