Mise en évidence des phases majeures de sédimentation dans le dépôt des formations sédimentaires de l’est du bassin sédimentaire tertiaire-quaternaire "onshore" de côte d’ivoire par l’étude de "stone-line"

Stone-lines are an alignment of solid materials observed at Bingerville in the old quarries and at Alépé on the trenches of road. They consist of sub-angular blocks of coarse ferruginous sandstone at Bingerville; and quartz pebbles in Alépé. The study of the stone-line allowed to highlight sediment levels altered in the sequence of sedimentary formations of the eastern onshore sedimentary basin of Côte d'Ivoire. The petrographic correlative analyzes of the solid material in stone-line allowed to determine their origin. Scanning electron microscopy allowed to highlight the depositional environment of the stone-line. Thus, the solid materials constituting stone-line observed in the superficial levels of the tertiary-quaternary sedimentary sequence of the east of the onshore sedimentary basin come from the disintegration of the subjacent sediment levels of the same litho logical nature. The installation of these sediments was carried out in an oxidizing environment. The sedimentary formations encountered in the east of the onshore sedimentary basin of Côte d'Ivoire were therefore set up during two major phases of sedimentation. The first phase of sedimentation is at the origin of the deposit of the extra formational sediments and the second phase is responsible for the deposition of intraformational sediments.