K-AR AGES OF NEOGENE VOLCAMIC ROCKS FROM THE NOTO PENINSULA

Abstract

K-Ar age determinations were carried out on 12 volcanic rocks from the Noto Peninsula. Ages range from 8.64 to 27.9 Ma and are generally consistent with paleontological and stratigraphical data. Ages of volcanic rocks from the Anamizu Formation are grouped into two: 24-28 Ma in the northeast part and 16-17 Ma in the northwest part. Rocks from the Yanagida Formation give ages of 15.2 and 19.7 Ma, the former is slightly younger than expected by micropaleontological data. The Iwakurayama Rhyolite and the Kurosaki Volcanics are dated at 16.1 and 8.64 Ma, respectively.