K-Ar ages of volcanic rocks from the Himeshima volcanic group, northern Kyushu, Japan

Quaternary adakitic volcanism along the volcanic front of Western Honshu and northern Kyushu has been attributed to slab melting of the young, hot Shikoku Basin oceanic crust. However, the timing and magnitude of magma production at the northernmost end of the Kyushu volcanic front, represented by the Himeshima volcanic group, remain insufficiently constrained. In this study, we present new K–Ar ages obtained using the unspiked sensitivity method combined with petrographic and whole-rock geochemical data to refine the volcanic history of the Himeshima volcanic group.