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Ohata Formation Uemura and Saito, 1957

• Type locality: Komena, Ohata town, Mutsu city, Aomori prefecture
• Coherent formation
• Pliocene
• Intruded by: Augite hypersthene andesite

• Sedimentary facies: Lacustrine?
• Lithofacies (Upper): Pumiceous tuff
• Lithofacies (Middle): Interbedded sandstone/mudstone and pumiceous tuff
• Lithofacies (Lower): Mudstone
• Lithofacies (Basal): Conglomerate

• Thickness: 100 - 450 m
• Upper limit: Unconformity, Conformity? (Komena Dacite)
• Lower limit: Unconformity (Sai Formation, Yagen Formation, Ikokuma Andesites, Yunokawa Formation, Yunokogawa Formation)

• Distribution: Oma city - Sai city, Shimokita county, Aomori pref.; Ohata river, Komena, Ohata town, Mutsu city, Aomori pref.; Shinsuke creek - Mena river, Kawauchi town, Mutsu city, Aomori pref.
• Fossils: Plants (Lignite)

• Uemura (1975) Geology of the Mutsukawauchi District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 39p. (in Japanese with English abstract 7p.)
• Uemura (1962) Oma and Sai, Explanatory Text of the Geological Map of Japan, Scale 1:50,000, Geological Survey of Japan, 39p. (in Japanese with English abstract 6p.)
• Uemura and Saito (1957) Ohata, Explanatory Text of the Geological Map of Japan, Scale 1:50,000, Geological Survey of Japan, 31p. (in Japanese with English abstract 8p.)