Located in the southwestern of the Oume-Fettekro greenstone belt, the Agbahou gold deposit is controlled by structural factors. Geophysics, teledetection and core data suggest the presence of NE and NW faults. However, the NEfaults define two major shear zones (ATZ: Agbahou Tectonic Zone and WTZ: West Tectonic Zone) that control the Agbahou gold mineralization. These first order structures are subparallel to the regional tectonic grain mostly north-east oriented. They seem to respectively develop on the both arms (eastern and western) of an anticline moderately plunging ~25˚ towards northeast. Each shear-zone contains several second-order shear-zones or lenses of variable direction and of 50˚ -80˚ dip. NW-faults however correspond to strike-slip faults and their development should be related to transcurrent tectonics. They acted as control channels on the distribution of gold mineralizations. The ductile-brittle character of shear-zones favored the ascent of hydrothermal fluids and the formation of multiple auriferous quartz veins: veins Type IIa and veins Type IIb relating respectively to the shear-veins and extensional veins. However, Agbahou also shows the existence of a disseminated sulphides-bearing mineralization within host-rocks. At Agbahou, the precipitation of gold probably occurred in a post to late ductile-brittle deformation period.

Les travaux réalisés dans la région de Doropo, au Nord-Est de la Côte d’Ivoire dans le domaine paléoprotérozoïque, ont permis de mettre à jour les informations géologiques préexistantes. C’est une zone caractérisée par un socle granito-gneissique et affectée par une importante couverture latéritique. Cela a rendu cette région longtemps inaccessible pour y mener des travaux de recherche. Les récentes campagnes de terrain réalisées au cours de cette étude ont révélé une lithologie constituée de granite à biotite, granite gneissique et migmatitique, granodiorite, gabbro, amphibolite et rhyolite. Ces formations ont été affectées par des structures majeures telles que les foliations, fractures, couloirs de cisaillements, plis et fractures. Ces structures sont pour la plupart orientées principalement NE-SW. Ce qui suggère que la déformation ayant prévalu dans la région est une compression NW-SE.  The work carried out in the Doropo region, located in the northeast of Côte d'Ivoire in the Paleoproterozoic domain, has allowed the updating of pre-existing geological information. It is an area characterized by a granite-gneissic basement and affected by an important lateritic cover. This has made the area inaccessible for a long time for any exploration work. The recent field trip carried out during this study revealed a lithology that includes biotite granite, gneissic and migmatitic granite, granodiorite, gabbro, amphibolite and rhyolite. These lithologies have been affected by major structures such as foliations, fractures, shear bands, folds and fractures. These structures are mostly oriented mainly NE-SW. This suggests that the deformation that has prevailed in the region is a NW-SE compression.

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Irbiben is a small gold deposit of the Precambrian inlier Tagragra d'Akka located in the Moroccan western Anti-Atlas, approximately 160 km southeast from Tiznit. Petrographic study shows that host rocks of Irbiben deposit are green schist facies metamorphic rocks, like metamorphic sandstone and schist, meta-pelite and quartzite. Gold is located in quartz veins or host rock with frequent injections of quartz. The petrographic characterization of alteration through the description of the alteration profiles and the comparative study of protolith and altered rocks showed a development of dominant quartz and calcite in mineralization wall-rocks. In moving away from it, there is rather sericite and chlorite. These phenomena are materialized respectively by the development of SiO 2 and CaO in the wall-rocks but rather that ferromagnesian elements (FeO, MgO) and K 2 O away from the mineralization. These trends were demonstrated by the geochemical study through Harker diagrams, description of alteration profiles, comparative study of protolith and altered rocks, and use of a new alteration index, MIA, elaborated during this work.