Structural Evolution of a Polyphase Salt‐Tectonic System From Syn‐Rift Extension to Syn‐Orogenic Deformation in the Middle Atlas (Oum Er Rbia Region, Morocco)

Salt tectonics has received little attention in the Middle Atlas, despite the widespread occurrence of Triassic evaporites and their potential to exert first‐order control on basin architecture and deformation. This study presents the first integrated analysis of polyphase salt tectonics in the Middle Atlas, focusing on the Oum Er‐Rbia sector, and documents the evolution of salt‐controlled basins from Jurassic rifting to later inversion. Our approach combines detailed field‐based stratigraphic and structural observations, high‐resolution geological mapping, and restored cross‐sections to reconstruct the kinematic evolution of minibasins. During Lower Jurassic rifting, extension was primarily accommodated by basement‐rooted normal faults, which localized salt movement and promoted the development of diapiric ridges and asymmetric minibasins. These basins record syn‐depositional tilting, salt‐related growth strata, and strong lateral thickness variations, reflecting close coupling between salt flow and sedimentation. By the end of the Lower Jurassic, continued salt withdrawal led most of the thickest minibasins to ground onto the Triassic basaltic substratum, forming primary welds that effectively shut down further subsidence (Ouhoudi and Khdoud minibasins). This transition triggered a major reorganization, allowing Toarcian‐Aalenian sediments to be deposited directly onto Triassic salt above collapsing diapirs. During later shortening, uplift of the Aït Bou Mazzough dome led to inversion of Jurassic minibasins, resulting in their tilting, thrust‐weld development, and the formation of syn‐compressional salt‐related minibasins. These results reveal fundamental mechanisms by which salt tectonics exerts long‐lived control on deformation and basin evolution, with implications extending beyond the specific case of the Middle Atlas.