Analysis of the composition of the early Upper Paleolithic stone industry from the Ushbulak site based on experimental data

The article presents the results of studying production of blades in lithic industry of cultural layers 6 and 7 at the Upper Paleolithic Ushbulak site (East Kazakhstan). According to the radiocarbon dates (ca. 45-36 kyr BP) and artifacts’ typological appearance, the complex of cultural layers 6 and 7 is associated with the initial stages of the Upper Paleolithic. The composition of stone industry has made it possible to establish the function of the site as a workshop for blade production. The study was based on a comparative analysis of archaeological artifacts and experimental flakes obtained from modeling the technology of blade production in the stone industry of cultural layers 6 and 7. The main research methods were attributive approach and nonparametric statistical methods (Mann-Whitney U-test and Pearson’s Chi-square). Experimental products have been analyzed and removals revealing the stage of shaping core performs from the blocks of raw material have been identified. These removals are distinguished by large sizes, preservation of cortex on their dorsal surface, and often the lack of a specially prepared striking platform. Comparison of the experimental sampling reflecting the full cycle of blade production with the archaeological collection has shown a large number of differences. However, when the spalls of primary preparation of cores were excluded from experimental sampling, it became almost identical to the collection of flakes from the stone industry of cultural layers 6 and 7. It can be argued that the initial precore preparation must have been carried out outside the excavation area, possibly directly at the outcrops of raw materials, and the prepared preforms were subsequently brought to the site.