The Talat n’Imjjad shear zone defines a well-expressed structural corridor within the Al Medinet quartz diorite, along the northern margin of the western High Atlas. This intrusion, dated at 514 ± 3 Ma, corresponds to early Cambrian magmatism emplaced during intracontinental rifting along the northern Gondwanan margin. It is affected by pervasive greenschist-facies alteration and deformation, particularly along its margins, where a NW–SE-trending sinistral shear zone hosts the Cu–Au–Bi mineralization. The mineralization at Talat n’Imjjad occurs as quartz and quartz–sulfide vein systems oriented NW–SE. The main mineralized structure can be mapped over ∼200 m, with vein thickness ranging from a few decimeters to ∼20 cm. At outcrop scale, mineralization is hosted within intensely deformed shear zones affecting the quartz diorite, where the original igneous texture is completely obliterated by pervasive hydrothermal alteration and the development of a penetrative mylonitic fabric. At depth, mineralization occurs in two main styles: (i) massive quartz–calcite veins and (ii) disseminated to veinlet-controlled chalcopyrite mineralization.

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