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Kumotoriyama Unit (Hisada, 1984) Hara and Hisada, 1998

Invalid synonym: Kumotoriyama Formation, Mizune Formation

• Type locality: summit of Mount Kumotori - Karamatsu valley - Nippara river, Okutama city, Nishitama county, Tokyo
• Accretionary complex
• Deposition (Limestone): Late Jurassic - Early Cretaceous
• Deposition (Chert): Early - Late Cretaceous
• Deposition (Shale): Late Cretaceous, late Turonian - middle Campanian
• Accretion: Late Cretaceous, Turonian - Campanian
• Correlation (Limestone): Torinosu Group

• Sedimentary facies: Marine
• Lithofacies: Mélange facies
• Lithofacies: Mudstone
• Lithofacies (Minor): Sandstone, Siliceous shale, Tuffaceous shale, Chert, Basalt, Limestone, Dolerite
• Sedimentary structures: Graded bedding

• Thickness: ca. 3,000 m or thicker
• Upper limit: Thrust fault (Ichinosawa Unit)
• Lower limit: Thrust fault (Happyakudani Unit)

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

• Distribution: summit of Mount Kumotoriyama, Saitama pref. - Tokyo; Karamatsu valley - Nippara river - Mizunezawa valley, Okutama city, Nishitama county, Tokyo; Kitaakikawa - Fujiwara - Hisato, Hinohara city, Nishitama county, Tokyo; Sogoyadani valley - Arasawadani valley - Takikawa river - Magarisawa creek, Otaki, Chichibu city, Saitama pref.
• ���� (Radiolarians): Acanthocircus sp., Alievium gallowayi, Alievium praegallowayi, Amphipyndax alamedaensis, Amphipyndax ellipticus, Amphipyndx cf. plousios, Amphipyndax stocki, Archaeodictyomitra sp., Archaeospongoprunum cortinensis, Carpocanapsis castatum, Cornutella sp., Cryptamphorella sphaerica, Diacanthocapsa umbilicata, Dictyomitra formosa, Dictyomitra koslovae, Dictyomitra multicostata, Hemicryptocapsa polihedra, Holocryptocanium barbui, Holocryptocanium geysersensis, Mita sp., Patulibrackium sp., Pseudoaulophacus floresensis, Pseudoaulophacus lenticulatus, Pseudodictyomitra nakasekoi, Pseudodictyomitra pseudomacrocephala, Stichomitra sp., Thanarla elegantissima, Thanarla praeveneta, Tricolocapsa 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.)
• Sakai (1987) Geology of the Itsukaichi District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 75p. (in Japanese with English abstract 5p.)