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Shimanto Supergroup (Ehara, 1926)

Synonym: Shimanto belt, Shimanto Group, Shimanto Formation

Invalid synonym: Nenoyama Formation (Local name in Yokoze city, Saitama pref.)

• Type locality: Shimanto river, Kochi prefecture
• Accretionary complex
• Forearc basin sediments
• Deposition (Limestone): Permian, Triassic (202 - 251 Ma K-Ar)
• Deposition (Chert): Triassic
• Deposition (Clastic rocks): Early - Middle Jurassic
• Accretion: Jurassic
• Contemporaneous heterotopic facies: Tsuchishio Formation
• Transitional: Tsuchishio Formation
• Correlation: Tsuchishio Formation

• Sedimentary facies: Marine
• Depth of water: Middle bathyal
• Metamorphic facies: Greenschist
• Lithofacies: Bluish green siltstone (Main), Conglomerate (Lower)
• Lithofacies: Mélange facies, Coherent facies (Chert-clastic sequence), Broken facies
• Matrix: Slate, Mudstone, Pale green siliceous tuff
• Exotic blocks (Crusts, Slabs): Greenstones, Pale red chert, Limestone
• Sedimentary structures: Planar cross-stratification, Slump structures, Dish structures

• Thickness: 500 m
• Upper limit: Butsuzo tectonic line
• Lower limit: Unknown

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

• Distribution: Boso peninsula - southern Kanto - Akaishi mountains - Kii peninsula, southern Shikoku - southern Kyushu - Okinawa
• Fossils:

• Tokiwa et al. (2016) Jour. Geol. Soc. Japan, vol.122, no.12, pp.625-635.