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The Açdif gold deposit is located in the Zenaga Inlier (central Anti-Atlas), approximately 120 km southwest of the city of Ouarzazate. It hosts gold mineralization associated with a shear zone affecting the metamorphic and magmatic formations of the Eburnean basement. It mainly consists of alternating micaschists, augen gneisses, and orthogneiss. These crystalline rock assemblages are intruded by a variety of granitoids. These are the Azguemerzi granitoids, which are locally affected by Eburnean deformation. Subsequently, these facies are intersected by a swarm of mafic dykes, which show a variety of rocks ranging from microgabbro-dolerite to quartz diorite. Detailed mapping, petro-mineralogical investigations, and geochemistry of the major and trace elements of these magmatic intrusions suggests the following: (i) for the granodiorite rocks (deposited before the basic dykes), a calc-alkaline affinity, with a chemical signature similar to a syn-collisional context; (ii) for mafic dykes, a contemporaneous emplacement of these mafic intrusions with an evolutionary process controlled by fractional crystallization of the same magma of continental tholeiites, whose chemical composition is comparable to that of enriched MORBs (EMORBs). These continental tholeiites are related to a distensive tectonic context that would have affected the Zenaga inlier prior to the Pan-African orogeny. [ABSTRACT FROM AUTHOR]

The genesis of the base-metal massive sulfide deposits hosted within the Moroccan Hercynian Jebilet and Guemassa Massifs is still under debate. No consensus currently exists between the two models that have been proposed to explain the deposits, i.e., (1) syngenetic volcanogenic massive sulfide mineralization, and (2) synmetamorphic tectonic fluid-assisted epigenetic mineralization. Conversely, researchers agree that all Hercynian massive sulfide deposits in Morocco are deformed, even though 3D structural mapping at the deposit scale is still lacking. Therefore, while avoiding the use of a model-driven approach, the main aim of this contribution is to establish a first-order structural pattern and the controls of the Hajjar base metal deposit. We used a classical structural geology toolbox in surface and subsurface mining work to image finite strain at different levels. Our data demonstrate that: i) the Hajjar area is affected by a single foliation plane (not two) which developed during a single tectonic event encompassing a HT metamorphism. This syn-metamorphic deformation is not restricted to the Hajjar area, as it is widespread at the western Meseta scale, and it occurred during Late Carboniferous times; ii) the Hajjar ore deposit is hosted within a regional transpressive right-lateral NE-trending shear zone in which syn- to post-metamorphic ductile to brittle shear planes are responsible for significant inflexion (or virgation) of the foliation yielding an anastomosing pattern within the Hajjar shear zone. Again, this feature is not an exception, as various Late Carboniferous-Permian regional scale wrenching shear zones are recognized throughout the Hercynian Meseta orogenic segment. Finally, we present several lines of evidence emphasizing the role of deformation in terms of mechanical and fluid-assisted ore concentrations. [ABSTRACT FROM AUTHOR]