Updating of tectonic maps from the Beticsa tool to establish first order milestones of the geodynamic evolution of the Gibraltar Arc System

Abstract

The updating at 1:250.000 scale of a tectonic map of the western Betics, was an excellent opportunity to review an extensive bibliography and to try to establish first order milestones of the Miocene to Recent geodynamic evolution of the Betic Cordillera in particular, and of the Gibraltar Arc System in general. This latter includes the Betic-Rif orogenic belt, the Alboran and Argelian-Balearic basins and the arcuate accretionary prism situated in the Cadiz Gulf. In the Gibraltar Arc System, various structural domains coexist, characterized by their specific types of structures and kinematics. With respect to the Miocene to Recent time interval, they deformed contemporaneously, but with different local tectonic regimes, extensional and/or compressional. These structural domains end on, or are cut by, transfer zones. The analysis of the structural pattern of each of these domains (superposition of structures, transport direction, boundary conditions, …) permits to establish the relative chronology of the events which affected them. In turn, the milestones set up for each one of the domains seen as a whole, allow us to refine and/or validate geodynamic evolution models of the SAG within the Africa-Iberia convergence setting for the considered time interval.