Regional and local stress field orientation inferred from quantitative analyses of extension joints: Case study from southern Italy

An intense tectonic activity in eastern Sicily and southern Calabria (Italy) is well documented by the differential uplift of Late Quaternary coastlines and by the record of the strong historical earthquakes. The extensional belt that crosses this area is dominated by a well-established WNW-ESE–oriented stretching direction. However, this area is largely lacking of any structural analysis for defining the tectonics at a more local scale. The analysis of systematic extension joint sets affecting Pleistocene deposits presented in this paper allows to infer the causative tectonic stress tensor by means of a quantitative inversion technique. Local perturbations of the first-order regional stress field are consequently recognized. Such perturbations are interpreted as due to interferences between large active faults and their particular geometrical setting. These results contribute to the understanding of the Quaternary tectonic evolution and the present-day stress regime.