La tettonica trasversale dell’Appennino Settentrionale: il caso della Val Marecchia.

Structural, geological, sedimentological and geophysical data support the existence of transversal tectonics in the Val Marecchia area. Such tectonics is related to the migration of the deformational front and is expressed by dynamic and mobile activity. Until the Tortonian phase, the migration of the foredeep-thrust belt front regularly occurred involving turbiditic closure pelites and transversely delimiting them by the tectonic lineament Arezzo-Badia Tedalda. Afterwards, the counter-clockwise rotation of the Italian peninsula leads, since Lower Messinian, to the formation of tectonic arcs. Among these arcs, the Romagnan and Adriatic ones come to separate in correspondence with the Val Marecchia tectonic lineament via the formation of a depressed area bending inside of the Apenninic chain. Transversal tectonics is then related to different rates of migration of the deformational front, which in turn is probably linked to discontinuities and /or heterogeneities of the underlying basement.