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Hercynian basement rocks and Mesozoic ophiolites of the Calabria-Peloritani terrane drifted in the present position during the opening of western Mediterranean basins (namely Liguro-Provençal and Tyrrhenian basins) since the Oligocene. Basement rocks were partly involved by Alpine (late Cretaceous—Eocene) deformation and metamorphism before the onset of the drifting process. Even though the kinematics of the Alpine deformation in Calabria has been already defined, restoration of structural and kinematic data to the original position and orientation before the opening of the western Mediterranean has never been performed. In this work we present new structural and petrological data on a major tectonic contact of Alpine age exposed in central Calabria (Serre Massif). Structural and kinematic data are then restored at the original orientation in the early Oligocene time, to allow a correct tectonic interpretation. In the Serre Massif the Hercynian basement is sliced into three nappes emplaced during the Alpine orogeny. The upper nappe is formed by a nearly continuous section of the Hercynian crust, consisting of medium- to high-grade metamorphic rocks in the lower portion. The intermediate nappe mainly consists of orthogneisses, whereas the lower nappe is chiefly composed of phyllites. The contacts between the Alpine nappes are outlined by well developed mylonitic and cataclastic rocks. The Curinga-Girifalco Line is a well exposed shear zone that overprints mainly metapelitic rocks of the upper nappe and granitoid orthogneisses of the intermediate nappe. Mylonites of the intermediate nappe typically show overgrowths on garnet and hornblende with grossular-rich and tschermakitic composition, respectively. The Alpine mineral assemblage indicates that deformation took place in epidote-amphibolite facies at pressures ranging from 0.75 to 0.9 GPa. In the investigated area mylonites strike roughly WNW–ESE, with shallow dips towards SSW. Kinematic indicators in mylonites are mostly consistent with a top-to-the-SE shear sense in the present geographic coordinates. The mylonitic belt is affected by later extensional faults outlined by South-dipping cataclasite horizons. Published geochronological data indicate that mylonites and cataclasites developed in Eocene and early Miocene times, respectively. Considering rotational parameters coming from paleomagnetic studies and large-scale palinspastic reconstructions, the shear sense of the Curinga-Girifalco Line has been restored to the early Oligocene position and orientation. Through restoration a top-to-the-S shear sense is obtained. This result is in striking agreement with the convergence direction between Africa and W-Europe/Iberia during Eocene, computed from the North Atlantic magnetic anomalies. Our geodynamic reconstruction, combined with structural and petrological evidence, allows to relate the Curinga-Girifalco mylonites to a thrust related to the southeastern front of the double-verging Alpine chain. The adopted method could be used also for other exotic terranes, such as the Kabylie or the Corsica-Sardinia, to better constrain geometry and evolution of the southern Alpine belt. Keywords: Western Mediterranean evolution; Calabria-Peloritani terrane; Alpine metamorphic overprint; Shear zone; Palinspastic reconstruction

Active deformation in southern Italy is accommodated by a distributed number of faults with low-moderate slip rates. Outcropping extensional faults and mostly blind transcurrent faults are mapped within a western (or axial) and an eastern domain, respectively. We use a combination of continuous (2001.00-2011.84) and episodic (1995.68-2010.79) GNSS observations to firstly estimate the geodetic deformation rate on 32 faults. Geodetic results were successively compared with geological displacement estimates. In agreement with seismological and geological information, a net spatial segregation emerges between the extensional axial belt, and the eastern domain where strike-slip faults are geodetically active. Although uncertainties are at times large, average displacement rates show broadly consistent patterns within both domains. A longitudinal gradient in extension rate is observed for the axial fault array, with two sectors of higher magnitude (~. 0.8-1.7. mm/yr for individual faults). This result is consistent with geological observations and supports the notion that extension occurs in discrete patches. Faults of the eastern domain have lower (few 0.1 to ~. 1.2. mm/yr) strike-slip rates and an eastward-decreasing extensional component, but significant geodetic displacement is detected in areas lacking clear evidence of activity. Few faults with 1-2. mm/yr extension rate are locally found in the eastern domain, but, based on their limited length and on inconsistency with seismology and geology, they are considered as due to deep-seated gravitational spreading. For crustal faults, although geodetic slip and moment rates are larger than geological rates, the broad trend of long- to short-term rates is similar, indicating the feasibility of geodetic analysis to contribute estimating fault slip rate and testing tectonic models in the region. Whereas the western domain extension is thought to be controlled by potential energy related to the Tyrrhenian Moho uplift beneath the Apennines, strike-slip in the east is related to shear on inherited faults within the Adriatic crust. © 2014 Elsevier B.V.

The southern Tyrrhenian Sea margin is dominated by deformations whose kinematics are relatively poorly constrained, and different models have been proposed to account for its recent evolution. Analysis of new structural and space geodesy data, combined with available geophysical information, reveal a deformation field characterised by subhorizontal NW-SE directed shortening and SW-NE directed extension. The main recognised regional-scale structure comprises E-W trending fault zones, namely the Ustica-Eolie Line and the Mt. Kumeta-Alcantara Line, connected by the NW-SE trending Marettimo, Trapani, San Vito, Palermo, Gratteri-Mt. Mufara and Eolie faults. This fault network displays a remarkable dextral strike-slip character, and has the features of a strike-slip duplex, that we indicate as the Southern Tyrrhenian Strike-Slip Duplex (STSSD). Analysis of available geophysical data and regional considerations based on platetectonic reconstructions suggest that the STSSD is a primary feature of lithospheric-scale importance. Our strike-slip duplex model differs significantly from previously proposed passive margin interpretations for the Tyrrhenian Sea margin offshore northern Sicily. The results of this investigation show the effectiveness of an integrated, multidisciplinary approach in the study of active deformation margins