Tectono‐Stratigraphic and Thermal Evolution of the Western Betic Flysch: Implications for the Geodynamics of South Iberian Margin and Alboran Domain

International audienceThe Betic-Rif orogen is a key region to understand the evolution of the plate boundary between Africa and Iberia/Europe. This study focuses on the Flysch Complex, which is considered the sedimentary cover of a domain originally positioned between the Iberian and Alboran margins. Based on stratigraphic and depositional evolution constraints, evidence for salt tectonics, combined with new apatite fission-tracks (AFT) and (U-Th-Sm)/He ages from the Flysch Complex and the Subbetic Zone, we propose a geodynamic interpretation for the formation of the Betic Cordillera, accounting for moderate N-directed transport of the Flysch Complex and synchronous exhumation between External and Internal Zones of the Betic. Early contraction between Africa and Iberia/Europe is reflected in the Cretaceous Flysch basin by a prolonged period of residence in the partial annealing zone for AFT and onset of foreland subsidence at 50 Ma. This stage lasted until the Early to Middle Miocene (20-15 Ma), marked by the rapid succession, in less than 5 Ma, of the deposition of Cenozoic flysch and their rapid exhumation. This event is interpreted to reflect the W-directed retreating mantle delamination between Africa and Iberia margins at the origin of the collapse of the proto-Betic orogenic domain and formation of the Alboran domain