Punctuated Neogene tectonics and stratigraphy of the African-Iberian plate-boundary zone: concurrent development of Betic-Rif basins (southern Spain, northern Morocco)

Abstract

This paper integrates the sequence stratigraphic and tectonic data related to the Neogene geodynamic and palaeogeographic development of the African-Iberian plate boundary zone between Spain and Morocco. Though the dating of individual tectonostratigraphic sequences and their delimiting sequence boundaries varies in accuracy and precision, their apparent correlation strongly suggests contemporaneous development of the Betic and Rif basins. This may likely be attributed to regional changes of the overall compressional intra-plate stress field. This, in turn, was governed by coeval plate-kinematic changes related to the ongoing collisional convergence of Africa and Iberia. The Neogene succession is characterised by brief tectonic pulses that governed the sequence stratigraphic development of the Betic-Rif basins (NBR phases). It broadly correlates with the coeval sequences in the compressional foreland basins and extensional rift basins in front of the collisional Alpine and Pyrenean orogens (CRF phases). These regionally correlatable basinal deformation events indicate that stress-related episodic changes at the African-Iberian plate-boundary zone resulted in an essentially direct cause-and-effect relationship between the tectonostratigraphic evolution of Neogene basins in northern African (Morocco), southern Europe (Spain) and western Europe (France, Switzerland, Germany).