A proposal of tephra stratigraphic division based on the identification of volcanic ash soil and reconstruction of the late quaternary tephra sequence in southwestern Hokkaido

Paleoenvironmental changes in late Neogene to early Quaternary in southwestern Hokkaido, Japan : a stratigraphical-micropaleontological elucidation

Identification of Marker Tephras Based on Petrographic Properties and its Contribution to Quaternary Research in Hokkaido,Japan