The feeding of the eruptive activity of Etna volcano. The regional stress field as a constraint to magma uprising and eruption

An analysis of the structural lineaments, as observed on the middle and upper slopes of Etna volcano, was made with the aim of checking stress distribution within the volcanic structure. The observed features suggest that the deformation pattern of the volcanic edifice is compatible with a deviating stress field dominated by an E-W sinistral shear, with the maximum stress axes being oriented NE (σ¹) and NW (σ³) respectively. Such a framework appears to be consistent with the active regional stress field, as deduced from structural data and focal mechanism analyses. The role of the active stress field in the penetration, uprising and eruption of magma in the Etnean area is therefore discussed and some more general suggestions about the geodynamic evolution of eastern Sicily are made.