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Old ferricrete landscape dismantling in Central Africa rain forest zone: formation of the present downslope iron accumulations. Present downslope iron accumulations were investigated in the rainforest zone in southern Cameroon. Six clay and Fe-hydroxide dominated patterns have been identified and occur on the lower part of hill slopes. They can be subdivided in three different sequences, related to gentle, moderate or steep slopes. They are discontinuous with respect to the dismantling zone of the old ferricrete cap formed at Cretaceous period. They show a gradual development from a soft Fe-crust (carapace) to a vesicular facies that will, with time, cover the whole landscape again. To cite this article: É. Temgoua et al., C. R. Geoscience 334 (2002) 537-543.  2002 Académie des sciences / Éditions scientifiques et médicales Elsevier SAS tropical rain forest / slope / ferruginous accumulations / landsurface transformation / Cameroon Résumé -Des accumulations ferrugineuses actuelles ont été caractérisées en zone forestière humide du Sud-Cameroun dans le cadre de cette étude. Six faciès identifiés se mettent en place au bas des versants. Ces faciès sont répartis sur trois séquences, en fonction de la pente du versant. Ils sont discontinus sur les faciès de dégradation des vieilles cuirasses jadis formées pendant le Crétacé. Ils montrent une évolution progressive et évoluent vers un carapacement massif, puis vacuolaire, susceptible de recouvrir de nouveau tout le paysage. Pour citer cet article : É. Temgoua et al., C. R. Geoscience 334 (2002) 537-543.  2002 Académie des sciences / Éditions scientifiques et médicales Elsevier SAS zone forestière tropicale / versant / accumulations ferrugineuses / évolution du paysage / Cameroun Abridged versionThe ferricretes are in disequilibrium in tropical environments; they are degrading and dismantling [1,17]. The dismantling affects the landscape morphology [1,2,4,17]. The new landsurface shows present iron accumulations found on the lower part of hill slopes [2,9,14,15,19]. This study focuses on unknown downslope iron crusting processes in tropical humid zones. The Meyomessala study soil shows 15 horizons that have been grouped into three types I, II and III (Fig. 4).The downslope patterns are distributed into three sequences, illustrated in Figs. 3 and 4, which appear to derive from the same surface, and was entailed and eroded progressively from steep to moderate, and then to gentle slope [19]. The petrography data and water table fluctua- * Correspondance et tirés à part.