The Center for African Area Studies, Kyoto University
Doi
Abstract
Since 1989, a geological and paleontological expedition has been carried out in the Zairean part of the Western Rift Valley. During two field seasons, more than 600 fossil remains were collected in the Sinda basin, Gaty, Haut-Zaire, mainly as surface finds. This fossil collection contains 52 mammalian fossils which comprise the following taxa; ? Agriotherium, four proboscidean groups such as Prodeinotherium, ?Anancus, Mammuthus subplanifrons and Stegodon kaisensis, two Rhinocerotidae, i.e., ?Aceratherium and Brachypotherium, ?Sivatherium, Hippopotamus, and a bovid. The Sinda fauna is composed of both Miocene and Pliocene mammals and suggest that the strata including the fossils are of late Miocene to early Pliocene in age. This fauna resembles that from the Nkondo formation which is located in the Ugandan side of the Western Rift Valley. The composition of the fauna from the Sinda area may indicate a different paleoenvironment (probably more humid) in this area from that in contemporary East Africa. RESUME Depuis 1989, une expedition geologique et paleontologique est realisee dans la partie zairoise de la branche occidentale du Rift. Durant deux saisons, plus de 600 restes fossiles ont ete collectele basin de Sinda, Gaty, haut-za?re, principalement comme decouvertes de surface. Cette collection fossile contient 52 mammiferes fossiles qui comprennent les taxa suivant; ?Agriotherium, qutre groupes proboscidean tels que Prodeinotherium, ?Anancus, Mammuthus subplanifrons et Stegodon kaisensis, deux Rhinocerotidae par exemple, ?Aceratherium et Brachypotherium, ?Sivathrium, Hippopotamus, et un bovide. La faune de Sinda est composee des mammiferes du miocene et du pliocene et suggere que le strate inclus les fossils sont de l'age du miocene superieur au debut pliocene Cette faune ressemble celle de Nkondo formation qui est situee dans la partie ougandaise du Rift Occidental. La composition de la faune de l'aire de Sinda devra indique un paleoencironement different (probablement plus humide) dans cette aire de celui en l'est-aficain contemporain
