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Hakoyama Volcanic Rocks (Yagi, 1941)

Invalid synonym: Hakoyama Lava

• Type locality: Hakoyama, Nakano city, Nagano prefecture
• Volcanic rocks
• Pliocene (2.1 Ma, K-Ar)

• Lithofacies: Pyroxene andesite lava
• Lithofacies (Minor): Pyroclastic rocks

• Thickness: 200 m or thicker
• Upper limit: Unconformity (Alluvial fan deposit)
• Lower limit: Unconformity (Takai Shale Member)

• Distribution: Hakoyama - Yomase bridge - Sarashina pass, Nakano city, Nagano pref.

• Akahane et al. (1992) Geology of the Nakano District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 106p. (in Japanese with English abstract 4p.)