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Ryokami Unit (Fujimoto et al., 1957) Hara et al., 2010

Invalid synonym: Ryokami Formation, Ishifune Formation

• Accretionary complex
• Deposition (Limestone): Late Carboniferous - Late Permian (Fusulinids)
• Deposition (Chert): Middle Permian - Early Jurassic (Radiolarians, Conodonts)
• Deposition (Shale): Early - Middle Jurassic (Radiolarians)
• Accretion: Early - Middle Jurassic
• Correlation: Ohirayama Unit, Ogurayama Group
• Intruded by: Chichibu Tonalite

• Sedimentary facies: Marine
• Lithofacies: Sandstone, Mélange facies
• Lithofacies (Minor): Chert, Limestone, Basalt lava, Volcaniclastic rocks
• Matrix: Shale
• Matrix (Minor): Sandstone, Siliceous shale, Tuffaceous shale
• Exotic blocks (Crusts): Sandstone, Limestone, Chert, Basaltic rocks

• Upper limit: Osutakayama Thrust Fault (Nogurizawa Unit), Thrust fault (Ryokamiyama Chert Unit), Unconformity (Akahira Group)
• Lower limit: Mikuniyama Thrust Fault (Ogamata Unit)

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

• Distribution: Komori river - Susukigawa river, Ogano city, Chichibu county, Saitama pref.; Mount Ontakesan, Chichibu city - Ogano city, Chichibu county, Saitama pref.; Inohara - Kowaishi - Nakasori, Otaki, Chichibu city, Saitama pref.; Mount Tenmaruyama - Occhizawa, Ueno city, Tano county, Gunma pref.
• Fossils (Limestone): Corals, Bryozoans, Calcareous algae
• Fossils (Limestone, Fusulinids): Chusenella sp., Climacammina lagenalis, Doliolina claudiae, Hemigordius sp., Lagena sp., Lonsdaleia sp., Mizzia sp., Ozawainella sp., Pseudoliolina otakiensis, Pseudofusulina sp., Pseudoschwagerina sp., Schbertella sp., Schwagerina tscheruyschewi, Tetrataxis cf. conica, Triticites sp., Verbeekina sp.
• Fossils (Chert, Radiolarians): Archaeosemantis venusta, Archaeothamnulus okuchichibuensis, Canoptum triassicum, Follicucullus scholasticus, Follicucullus ventricosus, Ishigum spp., Katroma elliptica, Nazarovella sp., Orbicuriforma sp., Pactarentinia koikei, Pantanellium inornatum, Pantanellium? vrgenum, Parahsuum simplum, Parentactinia nakatsugawaensis, Parentactinia virgata, Poulpus sp., Protopsium sp., Pseudoalbaillella globosa, Pseudohekiodiscus sp., Pseudostylosphaera spp., Saitoum sp., Spongostephanidium longispinosum, Triassocampe nova, Yeharaia sp.
• Fossils (Shale, Radiolarians): Acanthocircus hexaspina, Archicapsa pachyderma, Bagotum pseudoerraticum, Dictyomitrella? kamoensis, Droltus spp., Eucyrtidiellum disparlle, Eucyrtidiellum unumaense, Hsuum fukazawaense, Hsuum matsuokai, Hsuum minoratum, Napra sp., Pantanellium spp., Parahsuum kanyoense, Parahsuum simplum, Parahsuum takarazawaense, Parvicingula gigantocornis, Parvicingula nanoconica, Stichocapsa spp., Tricolocapsa spp., Trillus sp., Wrangellium sp.
• Fossils (Chert, Conodonts): Ellisonia sp., Epigondolella abneptis, Neospathodus cf. homeri, Neospathodus cf. kockeli, Xaniognathus sp.

• Hara et al. (2010) Geology of the Mitsumine District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, AIST, 110p. (in Japanese with English abstract 4p.)
• Okubo and Horiguchi (1969) Geology of the Mamba District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 65p. (in Japanese with English abstract 5p.)