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Yunokawa Formation Ministry of International Trade and Industry, 1969

• Type locality: Wajiro creek - Yunokawa river, Kawauchi river, Kawauchi town, Mutsu city, Aomori prefecture
• Volcanic rocks
• Miocene
• Correlation: Upper Hinokigawa Formation, Ohatagawa Green Tuff Member, Yunokawa Green Tuff Member

• Sedimentary facies (Middle): Submarine pyroclastic flow
• Lithofacies (Upper): Andesitic tuff breccia
• Lithofacies (Upper, Minor): Tuff
• Lithofacies (Middle): Dacitic pumiceous tuff breccia, Tuff
• Lithofacies (Middle, Minor): Andesite - Dacite lava
• Lithofacies (Lower): Conglomerate, Pumiceous lapilli tuff, Tuffaceous sandstone, Tuffaceous mudstone

• Thickness: 460 m
• Upper limit: Unconformity (Ohata Formation, Yunokogawa Formation)
• Lower limit: Unconformity (Kinpachizawa Formation, Lower Hinokigawa Formation

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

• Distribution: Hatake - Kawauchi river, Kawauchi town, Mutsu city, Aomori pref.
• Fossils (Plants): Betula onbaraensis, Fagus sp., Fagus jobanensis, Liquidambar endoi, Acer subpictum, Acer cf. nipponicum

• Uemura (1975) Geology of the Mutsukawauchi District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 39p. (in Japanese with English abstract 7p.)