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Kuzumaki Formation Matsushima, 1952 ex Ogami and Murata, 1974

• Type locality: Not defined
• Accretionary complex
• Deposition (Limestone): late Carboniferous (Ammonoids, Corals)
• Deposition (Limestone): early Permian (Fusulinids)
• Deposition (Mudstone): Early Jurassic, Toarcian - Middle Jurassic, Bathonian (Radiolarians)
• Accretion: Middle Jurassic
• Intruded by: Ichinohe Pluton

• Sedimentary facies: Marine
• Lithofacies: Mélange facies
• Matrix: Slate, Mudstone
• Exotic blocks (Crusts): Chert, Basalt, Dolerite, Basaltic tuff, Limestone, Sandstone, Siliceous mudstone

• Thickness: 6,000 m
• Upper: Oritsume thrust fault (Kassenba Formation)

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

• Distribution: Mabechi river, Shiritaka, Kuzumaki city, Iwate county, Iwate pref.; Mount Oritsume - Nisatai, Ninohe city, Iwate pref.; Mount Ogura - Keisei pass, Kunohe city, Kunohe county, Iwate pref.; Omogishi - Kozuya - Anetai - Kotaki, Ichinohe city, Ninohe county, Iwate pref.
• Fossils (Limestone): Brachiopods, Chaetetids, Bryozoans
• Fossils (Limestone, Fusulinids): Schwagerina sp., Schuberttella sp., Tricites sp., Pseudoschwagerina sp.
• Fossils (Limestone, Ammonoids): Glaphyrites? sp., Pseudoparalegoceras sp., Fagingoceras sp., Neoglaphyrites sp., Pseudopronorites sp.
• Fossils (Limestone, Rugosa): Cystolonsdaleia? sp., Pararachnastraea sp., Heritschioides? sp., Diphyphyllum? sp. (or Fomichevella? sp.), Amandophyllum? sp.

• Tuzino et al. (2018) Geology of the Ichinohe District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, AIST, 161p. (in Japanese with English abstract 4p.)
• Ehiro et al. (2010) Jour. Geol. Soc. Japan, vol.116, no.4, pp.219-228 DOI