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The Cenozoic geological evolution of the Italian area is characterized by the formation of two major mountain chains - the Alps to the north and the Apennines throughout the peninsula - plus the opening of two oceanic basins (the Ligurian-Provençal and the Tyrrhenian Sea). Associated with the formation of these two belts, a volumetrically important and chemically complex magmatic activity developed. The Alps and the Apennines show very different styles of evolution: the Alps display double-verging growth, with the involvement of large volumes of basement and the exhumation of metamorphic rocks (thick-skinned tectonics). On the other hand, the Apennines are a single-verging belt, mostly characterized by thin-skinned tectonics and associated to a radial eastward translation (coupled to extensional tectonics in the Ligurian-Provençal, Tyrrhenian, and western Apennines areas). The Apennines generated an arc from the northern Apennines down to Sicily, possibly merging with the Maghrebides along the northern Africa coast. The different evolution of the Alpine and Apenninic belts is mirrored by the different geometry of the respective foredeep or foreland basins (shallow in the Alps and deep in the Apennines), as recorded also by the dip of the foreland monocline (shallow in the Alps, 2-4°, and steeper in the Apennines, 6-15°). The paradox is evident: the higher the belt, the thinner the foreland basin. The Alps consist of rocks belonging to the continental margings of the European and Adriatic-African plates, as well as remnants of Mesozoic intervening ocean(s). On the other hand, the Apennines, with the exception of the Calabro-Peloritani arc and other scattered basement outcrops, are mainly made up of rocks of Adriatic origin (Mesozoic Laziale-Abruzzese and Apulian carbonate platforms plus basinal successions), with subordinate ophiolites. From a magmatological point of view, the Alpine magmatism is essentially concentrated in a relatively narrow area, the so-called Insubric Lineament and in a relatively short time (mostly ~32-24 Ma). On the other hand, the Apennines-related igneous activity spans a larger time range (essentially from 22 Ma to Present), with several peaks in magma production. This magmatism took place over a much wider area, characterized by variable lithospheric thickness, Moho age and depth. On the basis of thermo-tectonic, magmatological, and plate-kinematics constraints, a geodynamic evolutionary model of the Italian area is proposed. We suggest that three subduction zones have been active and have consumed oceanic and, partially, continental lithosphere: the Alpine subduction zone, with the European plate under-thrusting the Adriatic microplate; the Apenninic subduction zone, with the ancient (Mesozoic?) Ionian/Mesogean oceanic lithosphere and the Adriatic micro-plate under-thrusting westward the European plate; and the Dinaric subduction zone, with the Adriatic micropate under-thrusting northeastward the European plate. Such a geodynamic scenario is summarised in a movie, spanning the last 50 Ma

Space geodesy data are used to verify whether plates move chaotically or rather follow a sort of tectonic mainstream. While independent lines of geological evidence support the existence of a global ordered flow of plate motions that is westerly polarized, the Terrestrial Reference Frame (TRF) presents limitations in describing absolute plate motions relative to the mantle. For these reasons we jointly estimated a new plate motions model and three different solutions of net lithospheric rotation. Considering the six major plate boundaries and variable source depths of the main Pacific hotspots, we adapted the TRF plate kinematics by global space geodesy to absolute plate motions models with respect to the mantle. All three reconstructions confirm (i) the tectonic mainstream and (ii) the net rotation of the lithosphere. We still do not know the precise trend of this tectonic flow and the velocity of the differential rotation. However, our results show that assuming faster Pacific motions, as the asthenospheric source of the hotspots would allow, the best lithospheric net rotation estimate is 13.4 +/- 0.7 cm yr(-1). This superfast solution seems in contradiction with present knowledge on the lithosphere decoupling, but it matches remarkably better with the geological constraints than those retrieved with slower Pacific motion and net rotation estimates. Assuming faster Pacific motion, it is shown that all plates move orderly 'westward' along the tectonic mainstream at different velocities and the equator of the lithospheric net rotation lies inside the corresponding tectonic mainstream latitude band (approximate to +/- 7 degrees), defined by the 1 sigma confidence intervals

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The northwestern side of the Sicily Channel in the central Mediterranean has been shaped by the occurrence of two independent tectonic processes that overlap each other, the Maghrebides-Apennines accretionary prism and the Sicily Channel rift. Since at least the Pliocene, these two processes have acted simultaneously, being respectively related to the Apennines subduction and to the African rift. Thrust sheets of the accretionary prism crosscut the almost orthogonal rift-related normal faults and vice versa. Analog modeling supports the kinematics inferred from regional structural data. Alkaline magmatism associated with the rift is more pronounced in the foreland of the prism, where the extension is more concentrated. This peculiar setting confirms how independently geodynamic processes can interact in the same area at the same time, suggesting that plate boundaries are passive features responding to far-field velocity fields of the lithosphere

The Messina Strait, that separates peninsular Italy from Sicily, is one of the most seismically active areas of the Mediterranean. The structure and seismotectonic setting of the region are poorly understood, although the area is highly populated and important infrastructures are planned there. New seismic reflection data have identified a number of faults, as well as a crustal scale NE-trending anticline few km north of the strait. These features are interpreted as due to active right-lateral transpression along the north-eastern Sicilian offshore, coexisting with extensional and right-lateral transtensional tectonics in the southern Messina Strait. This complex tectonic network appears to be controlled by independent and overlapping tectonic settings, due to the presence of a diffuse transfer zone between the SE-ward retreating Calabria subduction zone relative to slab advance in the western Sicilian side.

The northern Adriatic plate underwent Permian-Mesozoic rifting and was later shortened by three orogenic belts (i.e., Apennines, Alps and Dinarides) developed along three independent subduction zones. The inherited Mesozoic horst and graben grain determined structural undulations of the three thrust belts. Salients developed in grabens or more shaly basins, whereas recesses formed regularly around horsts. A new interpretation of seismic reflection profiles, subsidence rates from stratigraphic analysis, and GPS data prove that the three orogens surrounding the northern Adriatic plate are still active. The NE-ward migration of the Apennines subduction hinge determines the present-day faster subsidence rate in the western side of the northern Adriatic (> 1 mm/year). This is recorded also by the SW-ward dip of the foreland regional monocline, and the SW-ward increase of the depth of the Tyrrhenian sedimentary layer, as well as the increase in thickness of the Pliocene and Pleistocene sediments. These data indicate the dominant influence of the Apennines subduction, which controls the asymmetric subsidence in the northern Adriatic realm. The Dinarides front has been tilted by the Apennines subduction hinge, as shown by the eroded Dalmatian anticlines subsiding in the eastern Adriatic Sea. GPS data suggest that southward tilting of the western and central Southern Alps, whereas the eastern Southern Alps are uplifting. The obtained strain rates are on average within 20 nstrain/year. The horizontal shortening obtained from GPS velocities at the front of the three belts surrounding the northern Adriatic plate are about 2-3 mm/year (Northern Apennines), 1-2 mm/year (Southern Alps), and < 1 mm/year (Dinarides). The shortening directions tend to be perpendicular to the thrust belt fronts. The areas where the strain rate sharply decreases along a tectonic feature (e.g., the Ferrara salient, the Venetian foothills front) are proposed to be occupied by locked structures where stress is accumulating in the brittle layer and thus seismically prone. Finally, we speculate that, since the effects of three independent subduction zones coexist and overlap in the same area, plate boundaries are passive features