Preceramic Chronology of the Kanto: ICU Loc. 28C

Abstract

Nine places on the ICU Campus, Mitaka city, Tokyo, have yielded preceramic material. At Loc. 28C, in the Tachikawa terrace by the Nogawa, the material was grouped as A, B and C in the soft-loam and upper part of the hard-loam (28C Upper) and C' in the middle hard-loam (28C Lower) with main tool types as follows: A : trapezes with a scraper; B : points, backed-blades, and gravers ; C : a point and a trapeze; C': backed-blades. 28C Upper tools are of obsidian, brought in from Mt. Hakone; 28C Lower are of local stone, from the Musashino gravel bed. Tools comprise 34% of the total weight of the obsidian ; they lack prepared surfaces and many retain some natural surface. The tools of local stone have prepared surfaces and are generally small, but the flakes are large, and few retain any natural surface. The differences are due to the availability of materials and the more efficient use of obsidian. Similarities to the Moro knife type suggest that Moro may be contemporaneous with 28C Upper, also with Tsukimino I, and Sunagawa follows shortly after. The backedblades of 28C Lower are similar to Ichibazaka examples, placing the latter after Moro.