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Wadagawa Formation Iwai and Suzuki, 1957

Invalid synonym (Upper): Fukushima Formation

Invalid synonym (Middle): Asadokoro Formation

Invalid synonym (Lower): Maki Formation

Dochi Formation had been included since 1976.

• Type locality: Wada river, Yamadate, Shichinohe city, Kamikita county, Aomori prefecture
• Coherent formation
• Miocene (Onnagawa stage?)
• Correlation: Kozawa Formation
• Intruded by: Dacite

• Sedimentary facies: Marine
• Sedimentary facies: Subaqueous pyroclastic flow
• Depth of water: Relatively deep
• Lithofacies: Shale, Siliceous shale
• Lithofacies (Minor): Lapilli tuff, Pumice lapilli tuff
• Lithofacies (Middle, Minor): Dacite, Pyroclastic rocks
• Lithofacies (Lower, Minor): Rhyolitic pumice tuff

• Thickness: 420 m
• Upper limit: Conformity (Sasamoriyama Volcanic Rocks, Moura Andesites, Dochi Formation)
• Lower limit: Conformity (Yotsuzawa Formation, Higashidaki Formation), Unconformity (Itadome Formation)

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

• Distribution: Maki, Kominato - Tsubakiyama, Hiranai city, Higashitsugaru county, Aomori pref.; Wada river, Yamadate, Shichinohe city, Kamikita county, Aomori pref.; Dochi river, Shichinohe city, Kamikita county, Aomori pref.
• Fossils (Bivalves): Lucinoma acutilineata, Limatula kurodai, Delectopecten peckhami
• Fossils (Foraminifera): Ammonia tanosawaensis, Bulimina sp., Buliminell sp., Cassidulina laevigata carinata, Cassidulina marfareta, Cibicides malloryi, Cibicides nipponica, Cibicides pseudoungerianus, Cyclamina crbicularis, Epislominella takayanagii, Fissurina marginata, Florilus sp., Gaudryina yabei, Globocassidulina subglobosa depressa, Globorotalia sp., Guttulina sp., Gyroidinoides soldanii, Haplophragmoides trullissatam, Martinoliella communis, Melonis barlleeanus, Melonis pompilioides, Oolina costata, Pullenia pompilioides, Stilostomella lepidula, Trifarina kokozuraensis, Uvigerina proboscidea

• Kudo (2005) Geology of the Towada District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, AIST, 79p. (in Japanese with English abstract 3p.)
• Uemura (1983) Geology of the Asamushi District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 40p. (in Japanese with English abstract 4p.)
• Uemura (1976) Geology of the Wakinosawa District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 14p. (in Japanese with English abstract 3p.)