PyrocLastic Flow-like Deposit of Futagoyama Volcano

Abstract

Futagoyama volcanoes at Kunisaki peninsula, Kyushu, consist of many lava domes of pyroxene andesite, hornblende andesite and biotite hornblende dacite. Pumiceous deposit with two parts, stratified tuffuceous mud bed (the upper) and pumice rich bed (the lower), is found at Matamizu, the southern base of the volcanoes. Studying the deposit, it is concluded the the pumices were empted perhaps as pyroclastic flow from the Futagoyama volcanoes at its almost last stage and then deposited in the shallow water enviroment.