Petrochemical studies of the Cenozoic basaltic rocks from Mt. Mengame and Mt. Hiba, Hiroshima Prefecture

Abstract

There are many basaltic rocks such as zeolite bearing dolerite, analcime bearing olivine basalt and olivine basalt, erupted in Pliocene to Pleistocene time along a border between Hiroshima and Tottori Prefectures. Petrographically the basaltic rocks are characterized by the presence of abundant olivine, titanaugite and anorthoclase. Twenty six representative rocks are chemically analyzed. It is suggested that the basaltic rocks are derived from an alkali olivine basalt magma.