Paleoenvironnement de mise en place des facies detritiques terrigenes de la formation du Moungo-fleuve dans le bassin sedimentaire du Moungo (Ouest Cameroun) [ Paleoenvironment of implementing terrigenous clastic facies of the formation of Mungo-river in the sedimentary basin of Mungo (West Cameroon) ]

To contribute to the study of sedimentary formation of the Mungo series, studies on the Mungo river formation was effectuated in this work. The reconstitution of the paleoenvironment in which the formation was put into place has been done. From the granulometrical analyses, plurimodal histograms are indications of multiple sources of sediments. The granulometrical curve shows low gradient. The sediments are therefore very poorly to poorly sorted. The morphoscopical analyses reveals the presence of: quartz grains that has not been worn out and having been eroded from proximal source rocks; subspherical and shiny quartz grains having been subjected to an averagely long transportation; and spherical and shiny quartz grains having been subjected to relatively long transportation. The heavy mineral analyses reveal a variety of heavy minerals, which are indications that part of the sediments came from magmatic source rocks; also, the presence of andalousites is indicative of a metamorphic source rock. The examination of thin sections reveals that the rocks are essentially lithic arkose and litharenites.