Volcanic Impact Crater-like Topography to the West of Usu Volcano, Southwestern Hokkaido, Japan: Paleotopographies Found at the Irie Shell Midden National Historical Monument

摘要

Usu Volcano, one of the most active vol- canoes in Japan, has erupted many times in the past and produced abundant ash and pyroclastic flows, including some that have been dated. Even though Usu Volcano has been investigated many times, no studies have been done on paleotopographic features result- ing from ejecta that impacted in the vicinity of the volcano.