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Kawai Formation Imamura et al., 1958

Invalid synonym: Oro Formation, Anami Formation, Nabeyama Formation, Lower Tamatsukuri Formation, Yonago Andesite, Kabutoyama Member

• Type locality: Kawai, Oda city, Saitama prefecture
• Coherent formation
• middle Miocene (20 - 12.4 Ma, K-Ar)
• Correlation: Josoji Formation

• Sedimentary facies: Shallow marine
• Sedimentary facies (Minor): Lacustrine
• Sedimentary facies: Coastal - Offshore near the river mouth
• Lithofacies: Tholeiite
• Lithofacies: Conglomerate, Sandstone, Andesite - Dacite - Rhyolite lava, Andesite - Dacite hyaloclastite, Submarine pyroclastic flow deposit, Volcanic breccia (Pillow breccia)
• Lithofacies (Bottom, Minor): Conglomerate
• Sedimentary structures (Minor): Graded bedding, Reversed graded bedding, Parallel stratification, Low-angle cross-stratification, Pipe rocks
• Sedimentary structures (Lava): Platy joints

• Thickness: 0 - 500 m
• Upper limit: Interfinggered (Kuri Formation), Unconformity (Omori Formation, Tsunozu Group)
• Lower limit: bottom of the felsic tuff bed
• Lower limit: Unconformity (Sada Formation, Hata Formation, Daito Granodiorite, Hiyodori Granite, Satsume Volcanic Rocks, Kamishima Volcanic Rocks, Shiota Body, Hosekidani Body, Shimokuno Granite, Makihara Complex, Yugakaigawa Volcanic Rocks)

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

• Distribution: Gotsu city, Shimane, Shimane pref.; Kawai - Ushibara - Nima - Takuno - Matsushiro - Ichihara - Fukuhara - Ishii - Asahara - Urizaka - Jinryo - Takamatsuji - Komatsuji, Oda city, Shimane pref.; Shinji town - Tamatsukuri - Sudani, Matsue city, Shimane pref.; Munakata, Yonago city, Shimane pref.; Takakubo - Suga - Sannoji - Kitamura - Bessho, Unnan city, Shimane pref.; Kisa town - Kadou town, Yasugi city, Shimane pref.; Miyauchi - Unate town - Mimiku town, Izumo city, Shimane pref.
• Fossils: Shellfishes (Freshwater), Fishes, Diatoms (Fluvial)
• Fossils (Shellfishes): Acila sp., Anadara daitokudoensis, Cardium sp., Cerithidea sp., Cyclammina sp., Dosinia cf. suketoensis, Gastropods, Gaudryina imamurai, Gaudryina ishikiensis, Gaudryina cf. oga, Gaudryina takunoensis, Macoma sp., Patinopecten (Kotorapecten) yamasakiensis ninohesis, Pecten sp., Sigmoilina imamurai, Siphotextularia cf. miocenica, Solen? sp., Striarca sp., Textularia agglutinaus, Textularia notoensis, Textularia semialata, Venericardia sp., Vicarya cf. japonica, Vicaryella sp.
• Fossils (Daijima-type flora)
• Fossils (Foraminifera): Ammodiscus incertus, Bathysiphon sp., Cribrostomoides cf. crassimargo, Cyclammina cancellata, Cyclammina pusilla, Discammina compressa Gaudryina ishikiensis, Gaudryina yabei, Globigerina adamantea, Globobulimina sp., Hippocrepinella sp., Martinottiella communis, Orbulina universa, Plectina nipponica, Recurvoides sp., Reophar spp., Spirosigmoilinella compressa

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