open access

https://doi.org/10.14943/2115.98742

https://hdl.handle.net/2115/98742

Reassessing the duration of the Hirosato-type microblade technocomplex : new radiocarbon dates from Location D of the Tatsuki site, Oketo Town

日本語

Hokkaido

2026-01-08

Laboratory of Archaeology, Graduate School of Humanities and Social Sciences, Hokkaido University

Bulletin of the Laboratory of Archaeology, Hokkaido University

5

10-21

12

This paper presents new radiocarbon dates from Location D of the Tatsuki site, an open-air Upper Paleolithic locality situated in Oketo Town, northeastern Hokkaido, Japan. These dates place the Hirosato-type microblade technocomplex-characterized by microblade production from burin-like blade-blank cores-within the Late Glacial period. Five charcoal samples, originally recovered during the 1956 excavation of Location D led by Toshio Oba, then a lecturer in the Anatomical Laboratory of the School of Medicine at Hokkaido University, were subjected to AMS radiocarbon dating. The results indicate two reliable chronological intervals: 21,956-21,425 cal BP and 18,615-17,958 cal BP. Incorporating these new results, a total of 16 radiocarbon determinations from five sites attributed to the Hirosato-type microblade technocomplex were evaluated. The dates exhibit a multimodal distribution with three discontinuous phases: 20,500-19,000 cal BP, 18,600-17,000 cal BP, and 15,200-13,800 cal BP. The estimated duration of this technocomplex spans approximately 7,200 years, from ca. 21,800 to 13,800 cal BP, though interrupted by two temporal hiatuses. Given that the Hirosato-type complex, currently known from only about 35 assemblages, is unlikely to have persisted for 7,200 years without significant technological change (i.e., continued reliance on blade-based microblade production), the apparent long duration with interruptions likely reflects selection biases rather than a continuous cultural tradition. Moreover, factors such as post-depositional disturbance and the old wood problem may have contributed to anomalously old radiocarbon dates, obscuring the actual temporal range of the Hirosato-type microblade technocomplex.

紀要論文

Version of Record

2760-1129