The Kapthurin Formation Revisited

This contribution reports on the results obtained from the 1980-7 research in the Kapthurin Formation (Baringo, Kenya) which aimed at the refinement of the chronology, stratigraphy and environmental evidence in order to establish a framework for the interpretation of the prehistoric sites. In 1966 a Late Acheulean industry with prepared-core technique and blade component, dated between ca 0.82/0.64 myr and 0.23 myr had been described in the area concerned. All the sites belong to the middle Kapthurin formation which is situated in the Bruhnes normal polarity chron and has a lower limit of 0.58 myr. The upper limit of 0.23 myr could not be confirmed. The fauna is consistent with the available dating evidence. The sites are situated in a flat savanna landscape which was built up by a braided river system under slightly more humid conditions than the present climate. On some of the sites artifacts were found in association with palaeosoils. Although the interpretation of such assemblages must consider the impact of natural turbation processes, the palaeosoils provide exceptional conditions for comparing sites from the same phase of landscape stabilization. The present archaeological evidence suggests a sequence of Late Acheulean and Post-Acheulean (Sangoan?, Middle Stone Age) assemblages rather than the presence of one single industry as described previously. The relation between these assemblages and the two mandibles of Homo sp. (aff. erectus) BK67 and BK8518 (found in 1966 and 1982) emphasizes the need for more research in the area. /// Cet article présente les résultats des recherches entre 1980 et 1987 dans la formation Kapthurin (Baringo, Kenya), l'accent étant mis sur la chronologie, la stratigraphie et le milieu, afin d'établir un cadre d'interprétation des sites préhistoriques. En 1966, un Acheuléen tardif avec technique de préparation du nucléus et production de lames, a été décrit dans la région concernée et datée entre ca 0.82/0.64 et 0.23 millions d'années. Tous les sites se trouvent dans la partie moyenne de la formation, qui appartient à l'époque Bruhnes de polarité normale. La limite inférieure est datée de 0.58 millions d'années, mais la date de 0.23 millions d'années pour la limite supérieure ne put être confirmée. Les restes fauniques sont en accord avec le cadre chronologique disponible. Les sites se trouvaient dans un paysage plat, de savannes, formé par un système de rivières anastomosées lors d'une phase climatique légèrement plus humid