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Aobunayama Pyroclastic Rocks and Lava Hayakawa, 1985

• Type locality: northeast of Lake Towada, Towada city, Aomori prefecture
• Type locality: Soryu fall, Oirase river, Towada city, Aomori prefecture
• Pre-caldera volcano
• Volcanic rocks
• late Pleistocene (ca. 0.2 - 0.07 Ma)

• Lithofacies: Olivine hypersthene augite andesite
• Lithofacies: Pumice fall deposit, Lahar deposit
• Lithofacies (Minor): Lava

• Thickness: ca. 20 - 150 m
• Upper limit: Unconformity (Towada-Okuse Pyroclastic Flow Deposit)
• Lower limit: Unconformity (Ohanabeyama Lava, Hakkoda 2nd-stage Pyroclastic Flow Deposit)

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

• Distribution: Lake Towada, Towada city, Aomori pref.; Soryu fall, Oirase river, Towada city, Aomori pref.
• Tephra: Toya Tuff

• 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.)