Evolution of segments of the central Apennine wedge through structural, geochemical, and geochronological constraints in fault zones

The timing of the progressive eastward migration of fluid-assisted orogenic (compressional) and post-orogenic (extensional) deformations in the Apennines is essentially constrained by stratigraphic data. Therefore, the reconstruction of tectonic evolution of the Apennine belt suffers from the paucity of high-resolution temporal constraints. Finding a more reliable methods for dating fault activity is therefore crucial to constrain the evolution of orogenic belts. Tectonic activity along faults is assisted by geofluids which are responsible for syn-tectonic mineralizations in different structures. Hence, such mineralizations offer the opportunity to unravel the fluid-assisted tectonic-thermal history of faults through time by coupling multiscale structural investigations, geochemical and radiometric analyses. The aim of the thesis is to constrain the compressional and post-compressional tectonic evolution of three segments of the central-northern Apennines and to frame them within the tectonic evolution of the central-northern Apennine wedge. To reach this aim, I studied the fluid-assisted deformation histories of three key area in the Apennines, where compressional deformation was followed by later extensional tectonics, through a multidisciplinary approach including geological- structural field observations, multiscale structural analyses, P-T tracers, and geochemical and radiometric analyses on syn-tectonic mineralizations. The studied areas are representative of an ideal transect oriented W-E across the Apennine belt and arranged from its inner portion (Tyrrhenian coast, to the west) to its axial sector (toward east and where extensional tectonics is actually active), passing through an intermediate sector of the belt. In detail, from W to the E, I focused on a thrust fault cut by later extensional faults exposed on Zannone Island (located on the western margin of the continental shelf in the central Italy), on an extensionally-inverted thrust fault exposed at Mt. Tancia (~50 km to the NE of Rome), and on compressional structures cut by later extensional structures exposed along the seismically active Mt. Gorzano normal Fault.