抄録
We report 24 radiocarbon ages using the benzene liquid scintillation method developed at Shizuoka University by FUKUHARA et al. (1995). Benzene was synthesized from buried wood from the Older-Fuji-Mud Flow, charcoals in the Sekotsuji Lava Flow, Kotengu Lava Flow, Fujikawabashi Lava Flow (Mt. Fuji) and Kawagodaira Pyroclastic Flow, and fossil land snail shells ( Kikai Island). The ^<14>C activity was measured using a low background liquid scintillation counter (Aloka-LBl) at the Radiochemistry Research Institute of Shizuoka University. Beta decay from benzene with respect to the standard and background with a window between 150 and 550 channels were detected every 20 minutes and repeated 73 to 225 times to obtain a sufficient count for statistical error estimation. Correction for δ^<13>C value was carried out. The standard used was NIST oxalic acid SRM 4990C, and the half-life used was Libby's half life. The ^<14>C ages of buried woods and charcoals of Fuji Volcano were between 1,2402±80yr. B.P. and 27,900±600yr. B.P. The ^<14>C ages of charcoal in the Kawagodaira pyroclastic flow was 2,900±llOyr. B.P.. The ^<14>C ages of fossil land snails of Kikai Island were 29,800±400yr. B.P. and 3,910±60yr.B.P..
We report 24 radiocarbon ages using the benzene liquid scintillation method developed at Shizuoka University by FUKUHARA et al. (1995). Benzene was synthesized from buried wood from the Older-Fuji-Mud Flow, charcoals in the Sekotsuji Lava Flow, Kotengu Lava Flow, Fujikawabashi Lava Flow (Mt. Fuji) and Kawagodaira Pyroclastic Flow, and fossil land snail shells ( Kikai Island). The ^<14>C activity was measured using a low background liquid scintillation counter (Aloka-LBl) at the Radiochemistry Research Institute of Shizuoka University. Beta decay from benzene with respect to the standard and background with a window between 150 and 550 channels were detected every 20 minutes and repeated 73 to 225 times to obtain a sufficient count for statistical error estimation. Correction for δ^<13>C value was carried out. The standard used was NIST oxalic acid SRM 4990C, and the half-life used was Libby's half life. The ^<14>C ages of buried woods and charcoals of Fuji Volcano were between 1,2402±80yr. B.P. and 27,900±600yr. B.P. The ^<14>C ages of charcoal in the Kawagodaira pyroclastic flow was 2,900±llOyr. B.P.. The ^<14>C ages of fossil land snails of Kikai Island were 29,800±400yr. B.P. and 3,910±60yr.B.P..
