Ushbulak-A New Stratified Upper Paleolithic Site in Northeastern Kazakhstan

We present the findings of excavations at the stratified site of Ushbulak, discovered during a joint Russian-Kazakhstan research project in 2016. The site is located in the Shilikty Valley, northeastern Kazakhstan, at the junction of routes connecting southwestern Central Asia, southern Siberia, and northern China. On the basis of stratigraphy, chronology, and technological evidence, we identify three technological complexes, relating to the Metal Ages (stratum 1), Final Upper Paleolithic (strata 2-4), and Initial Upper Paleolithic (strata 5.2-7). Focusing on the principal markers of the Initial Upper Paleolithic in the region, we conclude that finds from strata 5.2-7 belong to the southern Siberian-Mongolian variant of the Initial Upper Paleolithic, as evidenced by the uni- and bidirectional parallel volumetric blade core reduction, tool types, and absolute chronology. The tool kit includes mostly endscrapers, heavily retouched blades, and truncated-facetted or notched implements. Particularly diagnostic types include waisted blade, blade with a ventrally retouched distal edge, beveled point, backed blade, stemmed implement with a sharp tip, stemmed endscraper, and burin-core. Two AMS-dates from stratum 6 date this layer to ca 36,180 +/- 730 and 41,110 +/- 302 BP. The closest known parallels to the industry of the lower strata of Ushbulak are finds from horizon UP2 of Kara-Bom in the Russian Altai. Our results suggest that Ushbulak strata 5.2-7 correlate with the Initial Upper Paleolithic industries of the Altai (Denisova Cave), northern China (Luotoshi), and Mongolia (Tolbor-4 and -21).