関東山地,金勝山石英閃緑岩のK-Ar年齢
1983 年 78 巻 1 号 p. 38-39
詳細
1983 年 78 巻 1 号 p. 38-39
K-Ar dating on hornblende from biotite-hornblende quartz diorite in northeastern part of the Kanto Mountains was carried out. The age of the quartz diorite is 251±8 Ma. The result, together with geological facts, supports the idea that island arc composed of granitic plutons was present between the Sanbagawa and the Ryoke metamorphic belts.
