“上野玄武岩類-非島弧的火成活動の産物-(氏家, 1989)”の訂正
1990 年 85 巻 1 号 p. 34-36
詳細
1990 年 85 巻 1 号 p. 34-36
New trace-element data on several Ueno basaltic rocks, obtained by instrumental neutron activation and X-ray fluorescence analyses, show significantly low Ta and Nb values, thereby indicating that the rocks are “arc type” basalts. Most of old analyses on the Ueno basaltic rocks, cited by Ujike (1989), seem to have overestimated the Ta content. Therefore, Ujike's (1989) genetic model, in which these rocks could be derived from a “non-arc type” mantle material, a potential source of the Neogene alkalic volcanic rocks in west Japan, should be abandoned.
