Laboratoire de Géologie du Socle et de Métallogénie, UFR Sciences de la Terre et des ressources Minières, Université Félix Houphouët-Boigny Abidjan-Cocody, UFR STRM, 22 BP 582 Abidjan 22, Côte d’Ivoire
Our study area in southwestern Côte d’Ivoire in SASCA domain is part of the Archean-Paleoproterozoic transition zone and consists mainly of metasediments, grey gneisses, metabasites and granitoids. We present new data on the petrographic characterization and origin of metasediments in this area. Both field and petrographic observations indicate that metasediments consist of garnet-sillimanite-cordierite paragneisses and staurolite and/or garnet mica schists. The major elements made it possible to constrain the origin of these metasediments by showing: (i) their belonging to the group of iron-rich shales in majority and secondarily to the Fe-rich sandstones, (ii) their provenance from basalt and andesitic rocks moderately weathered (60