Geological controls on gold mineralization of the Nyangboué prospect in the southern part of the Boundiali-Syama belt, northwest Ivory Coast

Abstract

The Nyangboué gold prospect, situated in the Boundiali-Syama belt in northwest Ivory Coast, presents a significant target for understanding gold mineralization in West Africa. Through detailed mapping, petrography, and geochemical analyses of host rocks, this study investigates the geological factors controlling gold mineralization in the area. The result show that gold is hosted within a metasedimentary sequence, comprising meta-conglomerates, meta-graywackes, schists, and slates, which have undergone greenschist facies metamorphism. Three main deformation events influence the mineralization: D₁ compressive tectonics linked to S₁ schistosity, D₂ transcurrent deformation characterized by faulting and shear zones associated with S₂ schistosity, and D₃ transcurrent deformation producing schistose layering with S₃ schistosity. Gold and associated metallic minerals, including sulfides (e.g., pyrite, chalcopyrite, pyrrhotite, arsenopyrite, and galena) and oxides (e.g., magnetite and hematite), are found within quartz-carbonate veins and disseminated throughout the host rocks. Gold mineralization correlates with the D₂ deformation phase, with structural controls trending N-S to NNE-SSW. High-grade disseminated mineralization is most prevalent in slates and schists, whereas vein-hosted mineralization dominates in meta-conglomerates. This study enhances understanding of the structural and lithological controls on gold mineralization in the Boundiali-Syama belt, with implications for regional exploration strategies.