Variation in Middle and Upper Paleolithic reduction technology at Kara-Bom, the Altai Mountains: Refitting studies

Abstract

Primary reduction techniques used at the site of Kara-Bom in the Altai Mountains, are analyzed using the refitting method. In previous studies, the Kara-Bom assemblages provided the basis for reconstructing the evolution of lithic industries in the Altai Mountains over most of the Middle Paleolithic and at the early stages of the Upper Paleolithic (ca 60-30 ka BP). Under the new stratigraphic subdivision of Kara-Bom, four habitation stages are described. The refitting of artifacts from the Middle Paleolithic (MP2) layer indicates Levallois unidirectional convergent flaking aimed at producing points and blades as a co-product of reduction sequences. Based on cores and groups of spalls from the Upper Paleolithic layers UP2 and UP1, the variation of Upper Paleolithic reduction techniques is reconstructed and a conclusion is made that significant changes in core reduction occurred: the Middle Paleolithic (Levallois) flat unidirectional technique gave way to bidirectional volumetric subprismatic and prismatic reduction of the Upper Paleolithic type. The Kara-Bom assemblages appear to have been stable variants of blade technology aimed at producing large and medium-sized blades as well as reduction of narrow-faced cores aimed at producing bladelets. The comparison of Kara-Bom with contemporaneous industries of northern and eastern Central Asia suggests that the earliest Upper Paleolithic assemblages (before 35 ka BP) show a marked predominance of the Kara-Bom-type reduction techniques.