伊豆大島火山,北の山・伊東無コアの放射性炭素年代
2010 年 55 巻 5 号 p. 215-218
詳細
2010 年 55 巻 5 号 p. 215-218
Izu-Oshima volcano is one of the most active basaltic volcanoes in Japan, and consists of the pre-caldera older and younger edifices, the syn-caldera ejecta, and the post-caldera edifice. The Japan Metrological Agency made new boreholes on this volcano in 2009. We dated two carbon samples from the Kitanoyama core in the northwestern foot and the Ithonashi core in the northeastern flank. OSKT01 at -58.70m of the Kitanoyama core and OSIT01 at -69.35m of the Ithonashi core, which represent the upper part and the middle part of the pre-caldera younger edifice, are dated as 2040±70y BP and 9660±70y BP by AMS 14C method, respectively.
