Geological setting of the southern sector of the Roveto Valley (central Apennines, Italy).

New geologic data were collected in the southern sector of the Roveto Valley, which extends between Balsorano and Sora villages (Southern Latium, Central Italy). Many authors regard this zone as a key-area in the geological framework of the Central Apennines. The study, based on data correlation from photogeological analysis and field surveys (at 1:10,000 and 1:25,000 scale), was aimed towards the reconstruction of the Neogene-Quaternary evolution of this portion of the Apennine chain. Structural analysis indicates that the study area experienced a multi-stage tectonic activity, which involved the Latium-Abruzzi carbonate platform sequence and Plio-Quaternary continental deposits. Both remote sensing and geological mapping identified some tectonic features not previously described: - a NW-SE trending thrust at the base of the Colle Rotondo-Colle Terelle Ridge. The formation of this carbonate structure, that overrides the Western Marsica Ridge, is related to the deformation of the Marsica domain in Late Messinian time; - a NW-SE oriented splay thrust located near the Sora village and genetically connected to the Simbruini-Ernici Mts. main thrust; - left-lateral, strike-slip faults generated during a tectonic event which occurred after the thrusting and likely after the elevation and the sub-aerial exposure of the chain. The main NW-SE oriented faults related to this event were found: i) along the contact between Colle Rotondo-Colle Terelle Ridge and the Western Marsica Ridge (M.te Cornacchia); ii) along the north-eastern side of the Roveto Valley; - normal faults prevalently NW-SE oriented and clearly cutting and rejuvenating faults having strike-slip kinematics. Identification of such tectonic features enable us to reconstruct the complex structural setting of the area and to formulate a new assessment of the geological evolution of the southern sector of the Roveto Valley, from Late Miocene to Early Pleistocene.