K-Ar ages of the Mimuro and Mitsumori Granites, Chugoku district, Southwest Japan.

Geochemical variation of the Late Cretaceous-Paleogene granitoids across the Ehime-Hiroshima-Shimane transect, Japan

“…K-Ar age on biotite of the Mitsumori Granite revealed a Late Cretaceous in age of 81.8 ± 4.1 Ma (Matsuura, 1998), and the zircon U-Pb age is slightly older but still in the Late Cretaceous age of 86.2 ± 0.7…”