MORPHOLOGIE ET MORPHOGENESE DANS LE NORD DE LA COTE D IVOIRE. LA PART DU CLIMAT ACTUEL DANS LE MODELE DE LA SEQUENCE CUIRASSEE DOUNANGAKAHA (REGION DE KORHOGO)

This work aims to study, on landscape sequence with a ferricret crust on top (plintite) in the Ounangakaha sector, reliefs linked to current erosion processes.Datas are based on erosion measurements on the plintite sequence for clarifying the evolutions from a local base level studied by photointerpretation. Then, research on erosion traces and soil material, based on field studies, is carried to highlight the role of climatic variations.Results make appear three paleoclimatic levels (high plintiteon mountains, intermediate reliefs, upper glacis). Between these older plintite levels, and on material delivered by pedogenesis to current and sub-current erosion processes, depressions are hollowed around certain inselbergs or rock bars and low glacis or alluvial plains with plintite appear at the downstream of the older glacis.