ome remarks on the geodynamic of the Italian region

In this paper we present geological and geophysical data which constrain the Tertiary and Quaternary evolution of the Italian region, relevant to the interpretation of the genesis of magmatism in the frame of the geodynamic processes. GPS results show that, at the longitude of Sicily, the African approaches the Eurasian plate at a velocity of about 5 mm/yr in a NW direction. Furthermore, data show that the Adriatic foreland presently moves independently from the African plate. Geodetic and seismic data show that NW-SE oriented extension is the main active tectonic process in the Apennine chain. Relative and absolute motions of the Africa and the Eurasia plates indicate several hundred kilometers of convergence since the early Tertiary, in the central Mediterranean. This convergence has been achieved by northwestward dipping subduction of the African plate. The main present-day geodynamic feature of the Italian region is represented by seismicity on a well defined Benioff zone, which reveals a still active process of subduction from the Ionian foreland below the Calabrian Arc and Tyrrhenian Sea. This slab is the result of a NW directed long running subduction process active since the Tertiary, which consumed the Ligure oceanic basin first, then a small fragment of the Apulian continental lithosphere, and finally most of the present-day Ionian lithosphere, whose subduction is still ongoing. We also suggest that the lateral break-off of the Ionian subducting lithosphere could allow lateral astenospheric flow above the subducted plate either from the Apulian plate and from the Sicily Channell