ON THE AGE OF THE EARLY PALEOLITHIC ARTIFACTS FOUND ON THE NYU UPLAND, ÔITA PREF., NORTHERN KYUSHU (PRELIMINARY REPORT)

Abstract

About 50 stone implements (26 pebble tools, 17 flakes and 7 cores) have been found on the Nyu upland, east of Ôita City, northern Kyushu. They are quite similar to those of the Soan-culture of India, which runs through from the Mindel-Kiss interglacial to the Kiss glacial age. Nowhere were such implements ever seen in Japan. The culture characterized by such implements will be called “Nyuan-colture”. There are seven terraces in the Nyu upland, and the site is located on the second terrace of 60 to 90meters in height. The implements were gathered on the surface of the field, as a result of being dug ou by bull-dozers in the process of making an orchard garden, except one which was contained in the brecciaclay bed, the uppermost of the second terrace deposits. This clay is white or yellowish white and tuffaceous, and predominant in the upper part of the bed. The thickness of this clay layer is about 3 meters. It contains commonly angular and rounded gravels. The implement was found near the base of this clay layer. In the uppermost part of the clay layer a red soil has been developed. As a result of morphological investigation the authors recognized that this soil had been subjected to a kind of la erization. Some Japanese pedologists have considered the red soils of Japan are one of the zonal soils derid from various kinds of parent materials under the present bio-climatic conditions. But some others have opposed to this opinion, regarding those soils as paleosols judging from stratigraphical and geomorphological in-vestigations. The red soils with brilliant tone (10R-5YR) are widely distributed in northen Kyushu. The red soils as paleosols overlain by the welded tuff, which belongs to the Aso Volcano and one of the ejecta during the caldera forming period, or by the other type ejecta of the same origin, called the Y ene clay (tuffaceous clay), have been found in Yame-Kuroki district, south of Fukuoka City. In Japan if we attempt to find a time which the temperature was so high that red soils could be developed, and such warmer climate continued through the whole red soil forming period, it cannot be concim dered except an interglacial age. Therefore, it would be possible to say that the implements have passed at least one interglacial age.