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Koganetai Lava Muraoka and Takakura, 1988

• Type locality: 730 - 740 m above sea level of Ose river, Towada city, Aomori prefecture
• Pre-caldera volcanoes
• Volcanic rocks
• Pleistocene (0.29 Ma, K-Ar)

• Lithofacies: Olivine hypersthene augite basaltic andesite
• Lithofacies: Aa lava (several sheets)

• Thickness: 10 - 20 m
• Thickness (A sheet): several - 10 m
• Upper limit: Unconformity (Towada Hachinohe Pyroclastic Flow Deposit, Towada Chuseri Pyroclastic Fall Deposit)
• Lower limit: Unconformity (Minami-Hakkoda 2nd-stage Lava and Pyroclastic Rocks, Minami-Hakkoda 3rd-stage Lava and Pyroclastic Rocks, Hakkoda 2nd-stage Pyroclastic Flow Deposit)

------ Conformity, ~~~~~~ Unconformity, ~~~--- Local unconformity, '''/,, Interfingered, :::::: Fault, /--/-- Thrust, +__+__ Ground surface, ?--?-- Unknown

• Distribution: Ose river, Towada city, Aomori pref.; Sorigase creek, Okuse, Towada city, Aomori pref.

• Takarada and Muraoka (2004) Geology of the Hakkoda San District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, AIST, 86p. (in Japanese with English abstract 4p.)