GNGTS 2013 - Atti del 32° Convegno Nazionale

with the subduction of the Ionian lithospheric slab beneath the Calabrian arc the second one characterized by shallower hypocenters (down to about 30 km) is expression of the brittle strain crossing the whole orogen (Neri et al. , 1995). This latter seismogenic zone is strictly connected to the deformation field active within the hinge zone (Fig. 2). Statistical analysis allows to extract from the overall distribution of seismicity some clusters of events that belong to individual sequences of aftershocks. This analysis highlights that the hypocenters tend to concentrate around high-angle dipping surfaces; moreover, the elongation axes of the clusters are mainly oriented between WNW and NE, well fitting the orientation of the main fault bands (Giunta et al. , 2008). The analysis of the collected fault-plane solutions of the major events of the latter 30 years (DBMI11, Locati et al. , 2011; Pondrelli, 2004) shows transpressional and transtensional mechanisms likely related to NW-SE and NE-SW fault lineaments, and compressional and Fig. 1 – The brittle neotectonic pattern in the onshore and offshore sectors of the chain. Fig. 2 – Epicenter (A) and hypocenter (B) distribution in the area. 155 GNGTS 2013 S essione 1.2