Structural analysis and interpretation of stresses in the Kounsitel area (Gaoual, Republic of Guinea)

This study examines the structural geology of the Kounsitel gold district, located within the Bassarides region of West Africa. Its primary goal is to characterize the arrangement of geological features and to reconstruct the evolution of the stress fields that governed the deformation and mineralization processes. The methodology employed combines the interpretation of satellite imagery (Landsat 8 and 9, STRM) with detailed field observations from five specific locations: Kounsitel Centre, Concasseur, Bantala, Kérèrè, and Boumehoun. Analysis of extracted lineaments, utilizing rose diagrams, reveals three predominant structural orientations: NE–SW, NW–SE, and E–W. A detailed examination of structures such as quartz veins, massives quartz veins, schistosity, folds, and bedding indicates a polyphase tectonic evolution, characterized by alternating periods of compressive and extensive stress regimes. Quartz veins document multiple fracturing events influenced by successive rotations of the stress field. Later-forming massives quartz veins, occurring after the veins, signify a late-stage compressive phase. Schistosity, appearing in three generations (S1, S2, and S3), points to progressive deformation associated with the Pan-African orogeny. This deformation involved an initial shortening phase, followed by transpressive deformation, and concluded with a late reorganization of stresses. Collectively, these results underscore a significant structural control over gold mineralization, with the NE–SW and NW–SE orientations serving as preferred conduits for hydrothermal fluid flow. Consequently, this research enhances our understanding of orogenic gold systems and offers valuable insights for mineral exploration activities within the Kounsitel region.