| Summary: | 10th Alpine workshop "CorseAlp2011", 10-16 April 2011, Saint-Florent (Corsica) Detailed movements of small tectonic plates between larger plates have been difficult to assess due to their facility to move independently of those limiting plates and because the frequent vertical axis rotations they experienced during their evolution. The Iberian plate, located at the western boundary of the Tethys Ocean, is one of these conflicting plates. As has been pointed out in several published works the combined study of large scale plate motions together with field based results along plate boundaries must constrain as much as possible their evolution. The feedback between these two different scales of work should provide a better understanding of the evolution of the Iberian plate although there are still large conflicting areas and time periods that need to be understood. In this paper we try to discuss field observations from the Pyrenees and Betics within the frame of published large scale Iberian plate reconstructions. Starting in the Early-Middle Jurassic times the central Atlantic connected to the Alpine-Tethys separating Iberia from the north of Africa. The Iberia-Africa boundary resulted in a segmented margin characterized by a thinned crust with strong and multiple evidences of upper mantle exhumation and formation of oceanic crust (e.g., Schettino and Turco 2010). The northern propagation of the Northern Atlantic in Early Cretaceous times produced the abandonment of the Alpine-Tethys but the opening of the Bay of Biscay along the already rifted Pyrenean corridor with the concomitant counterclockwise rotation of Iberia. Upper mantle rocks were exhumed along the western side of the Pyrenees in the eastern oceanic crust pinpoint (e.g., Jammes et al., 2010). Further northern propagation of the North Atlantic Ocean also produced the end of the Pyrenean transtension close to the Early to Late Cretaceous boundary. The Iberian plate was thus an independent plate when Africa started northwards convergence against ...
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