Relazioni tra tettonica regionale quaternaria e deformazione vulcanogenica nelle aree dei Campi Flegrei, Isola di Ustica e Monte Vulture (Italia meridionale)

Abstract

Brittle deformations in pyroclastic rocks of three volcanic areas of southern Italy were studied in order to evaluate the bearing of regional tectonics on general deformation. Data indicate that deformation of single areas derives from the combination of regional tectonics and volcanism-induced strain processes. The Phlegrean Fields structure results from caldera formation and/or doming processes associated with a NNE-SSW regional extension. The Ustica fracture pattern (southern Tyrrhenian Sea) suggests that the island underwent left-lateral strike-slip tectonics along a deep E-W trending master fault followed by an inversion of the sense of shear during Pleistocene times. Mount Vulture Volcano, located at the front of the south-Apennines thrust belt, was deformed by contractional tectonics associated with doming. In this area, kinematics of fault planes suggest that the volcano changed from transpressional to transtensional conditions during middle Pleistocene (0.5 Ma).