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Onishi Formation

• Type locality: Onishi, Kuguno town, Takayama city, Gifu prefecture
• Accretionary complex
• Deposition (Shale): Middle Jurassic (Radiolarians)
• Jurassic
• Intruded by: Aoya Arculate Dyke, Granite porphyry dike, Gabbro dike, Andesite dike

• Sedimentary facies: Marine
• Lithofacies: Coherent facies (Chert-clastic sequence)
• Lithofacies: Sandstone-dominant interbedded sandstone and shale
• Lithofacies (Minor): Siliceous shale, Tuffaceous shale, Tuffaceous siltstone
• Sedimentary structures: Groove cast, Flute cast, Bounce cast
• Paleocurrent: from North to South, from Southwest to Northeast

• Distribution (South - North): 8 km or longer
• Upper limit: Unconformity (Kuzogawa Welded Tuff, Aoya Tuff, Nakanoshuku Tuff)

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

• Distribution: Onishi, Kuguno town, Takayama city, Gifu pref.; Takane town - Mount Marukuroyama - Lake Norikurako, Takayama city, Gifu pref.; Mangoku - Yojurodani valley, Asahi town, Takayama city, Gifu pref.
• Fossils (Shale): Radiolarians

• Yamada and Kobayashi (1988) Geology of the Ontakesan District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 136p. (in Japanese with English abstract 9p.)
• Yamada et al. (1985) Geology of the Takayama District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 111p. (in Japanese with English abstract 9p.)