Résumé
The study of volcano-sedimentary deposits of Mangbai in SE Mayo Oulo basin-Cameroon leads to the identification of five major distinct lithofacies types. From the coarset to the finest lithofacies, there are: Gb-clast supported by massive coble and boulder, Gg-granule to massive gravel, Sm-massive sand, Shhorizontal layered sandstones, Fml-massive laminated claystones. Coarse facies (Gb, Gg, Sm) are cemented with volcanic matrix while the finest facies (Sh, Fml) are normal sedimentary compacted deposits. The coarsest facies distribution is identified on the top SE of the mountain while the medium to finest facies deposits are located at the base of the sequence. The formation of the volcano-sedimentary deposits of Mangbai are associated to the development and establishment of Africa major rift system while sedimentary deposits in the Mayo Oulo basin are more recent and date from Lower Cretaceous.