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Fig.1 Geologic Columnar Section and Fission 　　Track Ages of the Odamaki Hills

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Correction to Tephrostratigraphy of the Odamaki Hills,
Chichibu City, Saitama Prefecture

Mizuo MACHIDA
Saitama Archaeological Center. 4-4-1 Funaki-dai, Osato-mura, Osato-gun, Saitama, 369-0108 Japan

　　The author reported the data of tephrostratigraphy and fission track ages of the Tama Volcanic Ash in the Odamaki Hills (Machida, M., 1996 and 1999). The author needs to report about the data, which to be corrected. This time, the author reports in this short note formally.
　　The Odamaki Hills, the summit level of which has an altitude of about 350-400 meters, are located between Chichibu City and Ogano Town, northwest of Chichibu City. The Airborne Tama Volcanic Ash is thickly deposited there. Stratigraphy of volcanic ash of the Odamaki Hills has been studied since old days and many papers have been published on it recently. Among them, geologic columnar section in the paper reported by Suzuki and Hayakawa (1990) is different from the paper of the Machida and Isoda. (1983). Concerning the result of the investigation of the geologic columnar section of the Odamaki Hills, the author could not deny the data of their paper, for their data had shown the refractive indices of minerals in the pumices. So the author followed their opinion, and reported two papers (Machida, 1996; 1999).
　　A recent work by Suzuki and Kurishima (2000) on tephra layers observed in a geologic columnar section in the Odamaki Hills indicated that the Hachioji Biotite Pumice (HBP) is indeed identical to the Odamaki Ash, since Machida, H. et al. (1974) has shown the HBP to be corelatable with TE-5. The work by Suzuki and Kurishima (2000) suggested that the HBP could be equated with both TE-5 and the Odamaki Ash. After reviewing stratigraphies and heavy mineral content (especially magnetite mineral) of these tephra layers, the author came to the conclusion that the identification made by Suzuki and Kurishima (2000) is indeed correct. Therefore, the columnar section and absolute ages in Machida (1999) should be replaced with the Fig. 1.
　　Also, the author would like to take this opportunity to correct the geologic columnar section and absolute age published in the author's earlier paper (Machida, 1996).