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International audience; We present the results of dynamic modeling of the western Mediterranean that accounts for observed global positioning system (GPS) surface deformation of the Alboran Sea and surrounding Rif and Betic Mountains as the result of the combined effects of relative motion of the Eurasian and Nubian plates, low strength in the Alboran Sea region and sub-lithospheric processes occurring beneath the External Rif domain. Assuming that the lithosphere behaves elastically over the short time period of the GPS observations, an elastic plate model is considered in our study, including an area of weak lithosphere (factor of 10) centered on the Alboran Sea and in which lateral boundary conditions consist of the Nubia-Eurasia oblique convergence. Sub-crustal processes are modeled by application of a horizontal traction on a small area (patch) at the base of the elastic plate. Our modeling studies demonstrate the need for sub-crustal or sub-lithospheric, southwestward-directed forcing to account for observed southwestward motion of the Rif and Betic domains. Based on the location, orientation, and small area of the traction patch, we hypothesize that forcing is associated with delamination and rollback of the subducted African continental lithospheric mantle beneath the External Rif zone, due to the pull of the oceanic part of the Western Mediterranean slab, a dynamic process that may be similar to that where the over-riding plate is driven toward the subduction zone during slab rollback.

Kinematic axes and resultant vectors of displacement along the Carpathian arc and the Apuseni Mountains aid in the reconstruction of retreating subduction along the Carpathians. The recent vertical position of the subducted slab below the Vrancea area of the eastern Carpathians represents the final rollback stage of a small fragment of oceanic lithosphere, formerly situated between the Moesian and East European plates. The ages and locations of the eruption centers of the andesitic volcanic chain along the Carpathian arc in the overriding plate as well as the thrust directions are used as markers to reconstruct the rollback area of the subducted slab between the Moesian and East European plates.