熊本大学学術リポジトリ Kumamoto University Repositor Title 阿蘇火山米塚の噴火年代 Author(s) 宮縁, 育夫 Citation 火山, 55(5): Issue date Type URL Right Journal

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(1)熊本大学学術リポジトリ Kumamoto University Repository System Title. 阿蘇火山、米塚の噴火年代. Author(s). 宮縁, 育夫. Citation. 火山, 55(5): 219-225. Issue date. 2010-10-31. Type. Journal Article. URL. http://hdl.handle.net/2298/37047. Right. © 2010 特定非営利活動法人日本火山学会.

(2) // (,*+*) / ,+3῍,,/ . . ῍ῐ῎῏ ῕ῒῌ῔῎ΐῑ ¥ ¦ + '" ,*+* , / - +- ./ ,*+* , +* - ,/ ./. Eruption Age of Komezuka at Aso Volcano, Japan Yasuo MIYABUCHI Komezuka Volcano, located in the northwestern part of the post-caldera central cones of Aso Volcano, SW Japan, is a basaltic monogenetic volcano comprising a scoria cone (-1*῍-2* m in basal diameter ; 2* m in height) and lava flows (+*./ km, ; /+*1 m-). We obtained +.C ages of -,*1*.* years BP from a buried soil below silty ash underlying Komezuka lava, which corresponds to -,-1*῍-,,+* cal years BP, and ,,10*.* years BP (,,3/*῍ ,,11* cal years BP) from a soil above silty ash overlying Komezuka lava. The age of soil below the lava suggests that the eruption age of Komezuka Volcano is about -,-** cal years BP. The eruption age is consistent with the age of Ojodake Volcano (-,0** cal years BP) whose lava underlies Komezuka lava. In the northwestern part of the post-caldera central cones, Late Holocene monogenetic volcanic activity commenced with sub-plinian eruptions and lava extrusion from Kishimadake Volcano at approximately .,*** cal years BP, followed by sub-plinian eruptions and lava extrusion from Ojodake Volcano at -,0** cal years BP, and ceased with strombolian eruptions and lava extrusion from Komezuka Volcano at -,-** cal years BP. Key words : Komezuka Volcano, scoria cone, lava flow, eruption age, Aso Volcano. + . . 9:;<=>;?@A B4CDE6 F;< L 3/..- m K MNOP@ QJR6SQT. ,**+ 0123456 78 +32/ G

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(141) ) .* +--ῌ+/+. Reimer, P. J., Baillie, M.G.L., Bard, E., Bayliss, A., Beck, J.W., Blackwell, P.G., Buck, C.E., Burr, G.S., Cutler, K. B., Damon, P.E., Edwards, R.L., Fairbanks, R.G., Friedrich, M., Guilderson, T.P., Herring, C., Hughen, K.A., Kromer, B., McCormac, F.G., Manning, S.W., Ramsey, C.B., Reimer, R.W., Remmele, S., Southon, J. R., Stuiver, M., Talamo, S., Taylor, F.W., van der Plicht, J. and Weyhenmeyer, C.E. (,**.) IntCal*. terrestrial radiocarbon age calibration, *ῌ,0 cal kyr BP. Radiocarbon, .0, +*,3ῌ+*/2. Talma, A.S. and Vogel, J.C. (+33-) A simplified approach to calibration +.C dates. Radiocarbon, -/, -+1ῌ-,,. 5 (+31.) XaH9Q *, T +"UVW no. ./ 3ῌ+*. 5 (+32.)

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熊本大学学術リポジトリ Kumamoto University Repositor Title 阿蘇火山 米塚の噴火年代 Author(s) 宮縁, 育夫 Citation 火山, 55(5): Issue date Type URL Right Journal

熊本大学学術リポジトリ Kumamoto University Repositor Title 阿蘇火山米塚の噴火年代 Author(s) 宮縁, 育夫 Citation 火山, 55(5): Issue date Type URL Right Journal