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Onagurayama Andesite Yashima et al., 1987

• Volcanic rocks
• Miocene (7.6 Ma, K-Ar)
• Intruded in: Takatama Formation

• Lithofacies: Tholeiite
• Lithofacies: Augite hypersthene andesite
• Lithofacies: Andesite lava (more than 10 flow units), Pyroclastic rocks
• Lithofacies (Minor): Basalt

• Source: in the vicinity of the summit of Mount Onagura
• Thickness: ca. 150 m
• Thickness (A flow unit): several - 30 m or thicker
• Lower limit: Unconformity (Takatama Formation)

• Distribution: Mount Onagura, Koriyama city - Motomiya city, Fukushima pref.

• Sakaguchi (1995) Geology of the Nihonmatsu District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 79p. (in Japanese with English abstract 4p.)