鹿児島県藺牟田火山溶岩のK-Ar年代
入来カオリン鉱床の生成時期と関連して
1989 年 84 巻 11 号 p. 398-402
詳細
1989 年 84 巻 11 号 p. 398-402
The K-Ar age determination was made on two lavas from the Imuta Volcano, Kagoshima Prefecture, southern Kyushu. The ages of these andesitic lavas are 0.346 ± 0.014 and 0.453 ± 0.018 Ma. This indicates that the Imuta Volcano lava is much younger than the others with gold mineralizations distributed in the northern part of Kagoshima Prefecture and may imply that the activity of the Imuta Volcano had continued for more than fifty thousand years. In addition, the age of the Imuta Volcano lava enables us to estimate the age of the Iriki kaolin deposit which is considered to have formed with a close relation to the early-stage activities of the Imuta Volcano.
