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Ebirase Formation Tamura, 1960

• Type locality: Shiraki - Yashikino, Ashikita city, Kumamoto prefecture
• Coherent formation
• Trench-slope deposits
• Late Jurassic - Early Cretaceous (Ammonoids, Radiolarians)
• Correlation: A part of Miyasono Formation

• Sedimentary facies: Marine
• Lithofacies (Upper, Main): Sandstone
• Lithofacies (Upper, Minor): Shale, Interbedded sandstone and shale
• Lithofacies (Middle, Main): Shale
• Lithofacies (Middle, Blocks): Chert, Torinosu type Limestone
• Lithofacies (Lower): Sandstone, Sandy siltstone
• Lithofacies (Minor): Siliceous tuff, Muddy limestone

• Thickness: 200 m or thicker
• Upper limit: Fault
• Lower limit: Conformity (Unit IV), Fault (Unit III)

• Distribution: Matsuno - Oiwa, Kuma city, Kumamoto pref.; Shiraki - Yashikino, Ashikita city, Kumamoto pref.
• Fossils: Radiolarians, Bivalves
• Fossils (Ammonoids): Decipia sp., Campylites sp.

• Onoue and Nishizono (2014) Jour. Geol. Soc. Japan, vol.120, Supplement, pp.1-17 DOI