著者

佐藤 二郎 井尻 正二

出版者

地学団体研究会

雑誌

地球科学 (ISSN:03666611)

巻号頁・発行日

vol.31, no.4, pp.149-155, 1977

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The purpose of the present article is to describe the mode of occurrence of the molar teeth M3 of Paleoparadoxia tabatai (TOKUNAGA) from "Wainai site" and to consider its archaeological significance. 1) Wainai site is situated on the river terrace at Wainai, Niisato-village, Shimohei-district, Iwate Prefecture, Northeastern Japan. This terrace might be formed at Wurm stage. 2) There are two cultural layers in the terrace deposits at Wainai site. Judging from designs and types of the ceramic tools accompanied, the lower and upper cultural layer may be of the latest Jomon Period and the latest Jomon or the earlist Yayoi Period respectively. Taking into account the circumstances at the time of excavation, it is presumed that the molar teeth were picked up from the lower cultural layer. 3) Among the strata developed in the vicinity of the Wainai site, the Oligocene Kogawa group, especially the Sawamagari formation distributed in Iwaizumi town, Iwate Prefecture is the most probable as the original horizon yield the molar teeth, although it is impossible to make sure the locality of the original fossil. 4) Based on the paleontological and archaeological experiences, the teeth seem to have been collected and processed in order to make the knocknack by the latest Jomon man. If this inference is correct, the teeth are the oldest Desmostylid specimen in Japan collected and processed by the pre-historic humanbeings.