Discovery of Miocene granitoids in eastern Fukui Prefecture, central Japan

Abstract

So-called late Cretaceous-Paleogene quartz monzodiorite stock (13 km²) and small dolerite dike in the Arashima-dake-Nakatatsu Pb-Zn mine area were dated as 18.3-20.9 Ma and 24.8 Ma, respectively. Thus, Miocene plutonic cycle should be added to the plutonic activity of eastern Fukui Prefecture, where Jurassic and late Cretaceous-Paleogene ones were recognized before. The Kadohara quartz monzodiorite is high-level portion of volcano-plutonic complex, which is a part of intense andesitic activity of the Green Tuff orogeny.