The Betic hinterland, in the westernmost Mediterranean, constitutes a unique example of a stack of metamorphic units that, in spite of the ongoing plate convergence between the African and Eurasian plates, experienced since the Middle Miocene rapid exhumation via extensional denudation by simultaneous normal faulting and vertical ductile thinning. Low-angle extensional faulting is also accompanied by tectonic unroofing of the lower plate, forming large-scale upper crustal domes that shape high-mountain ranges in this orogenic belt. Doming was caused by the interference of two orthogonal sets of Miocene-Pliocene, large-scale open folds that warp both the extensional detachments and their footwalls.

Using a three-dimensional model for the crustal structure of the Betics-Rif area, integrating surface geological data, the relationships with present-day topography, and the deep crustal structure, we document the role of crustal flow simultaneously to upper-crustal low-angle faulting in the origin and evolution of the topography. A geometrical model to relate the amount of horizontal extension along low-angle detachment faults is presented. It is also discussed the link between mountain uplift, upper-crustal denudation by low-angle faulting and the occurrence of a subhorizontal Moho in regions with high continental extension.

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