Mediterranean Tectonics

The Mediterranean area is characterized by marine basins surrounded by growing orogens, resulting from Mesozoic dispersion of Pangea, development of Tethys oceans and subsequent late Mesozoic to Recent convergence between Africa and Europe. The sub-basins of the Central-Western Mediterranean (Alboran, Valencia, Liguro-Provençal, Algerian and Tyrrhenian basins) developed essentially during the last 40–30 Ma and become younger from west to east. The Eastern Mediterranean is older, being floored by continental crust thinned during Mesozoic rifting phases and likely by remnant Mesozoic oceanic crust. The main subduction zones active at present in the Mediterranean are the Alps-Betics, the Apennines-Maghrebides, and the Dinarides-Hellenides-Taurides. The Mediterranean orogens associated with these subduction zones show two end member characteristics, mirroring those at the opposite sides of the Pacific Ocean. The Alps-Betics and Dinarides-Hellenides-Taurides are associated with E- or NE-directed subduction zones, show high morphological and structural elevation, double vergence, thick crust, involvement of deep crustal rocks, and shallow foredeeps. On the other hand, the Apennines-Maghrebides, occurring along a W-directed and “eastward” retreating subduction zone show low morphologic and structural elevation, single vergence, thin crust, involvement of shallow rocks, a deep foredeep and are associated with backarc basins (Valencia, Liguro-Provençal, Alboran, Algerian, Tyrrhenian Basins). The Cenozoic evolution of the area is the result of a combination of Africa-Europe convergence and interaction between postulated “eastward” mantle flow and subducting plates that produced “eastward” rollback of the Apennines-Maghrebides slab and consequent backarc basins development and “eastward” advancement of the Alps and Dinarides-Hellenides slabs toward the upper plates.