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Kuga Group Kojima and Okamura, 1952

• Type locality: Yamaguchi prefecture
• Accretionary complex
• Deposition (Limestone): Permian (Fusulinids)
• Deposition (Chert): Early Triassic, Jurassic (Conodonts, Radiolarians)
• Deposition (Mudstone): Triassic (Monotis sp.)
• Deposition (Sandstone): Late Jurassic (Ammonoids)
• Deposition (Mudstone): Jurassic (Radiolarians)
• Accretion: Jurassic (Radiolarians)
• Intruded by: Habu Granodiorite, Yasakakyo Granite, Etajima Granodiorite, Kure Granite, Gamano Granodiorite, Namera Granite, Shimokuhara Granite, Osogoe Complex, Nakayamagawa Complex, Iwakuni Granite, Rokuroshi Granite Porphyry Dike Swarms, Matsuyama Granodiorite, Towa Granodiorite, Hashirajima Granite, Dolerite dikes, Gabbro dikes, Quartz porphyry dikes, Porphyrite dikes

• Sedimentary facies: Marine
• Metamorphic facies: Ryoke Metamorphism
• Lithofacies: Hornfels, Biotite slate, Mica schist, Banded gneiss
• Lithofacies (Protolith): Mélange facies
• Matrix (Protolith): Mudstone
• Exotic blocks (Protolith, Crusts): Chert, Sandstone, Limestone, Greenstones, Siliceous shale

• Thickness: 1,500 - 4,000 m or thicker
• Distribution (East - West): 30 km
• Distribution (South - North): 30 km
• Upper limit: Unconformity (Takada Rhyolits, Ajina Formation, Yuridani Formation, Miwa Formation, Terrace Deposits (Tennoo), Terrace Deposits (Iwakuni))
• Lower limit: Transitional (Ryoke Metamorphic Rocks)

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

• Distribution: Nishikigawa river - Mikawa town - Miwa town - Watari - Higashitani - Yuritani - Arase - Kawaradani - Kurose - Momijigatao pass - Uegaichi - Nagatani - Shimoonegawa - Nekasa - Ikimigawa river - Hinata - Hata - Kamegasako - Kashiwayama - Ajina - Isekojima island - Hashima island - Kohashirajima island - Tsuzukijima islnad - Maeshima island, Iwakuni city, Yamaguchi pref.; Yagi town - Kamifukawa town - Shiraki town - Misasagawa river - Aratani - Sasagatoge pass - Mount Hokotoriyama - Masukoshi - Yusakatoge pass - Mount Kinomuneyama, Hiroshima city, Hiroshima pref.; Mount Notoroyama (Mount Uneyama) - Tsukumo - Lake Mitaka - Seto - Mount Hodaiyama, Etajima city, Hiroshima pref.; Kuroshima island - Kurahashijima island - Kashima island - Osakishimojima island - Itsukishima island, Kure city, Hiroshima pref.; Toyoshima island, Kamijima city, Ochi county, Ehime pref.; Koaishima island - Nakashima island, Matsuyama city, Ehime pref.; Kazuratani, Imabari city, Ehime pref.
• Fossils: Ammonoids (Perisphinctes sp.), Monotis mukaihatensis, Monotis typica, Trace fossils (Phycosiphon isp.)
• Fossils (Limestone): Fusulinella sp., Neoschwagerina sp., Profusulinella sp., Schwagerina sp., Triticites sp.
• Fossils (Radiolarians): Archaeodictyomitra sp., Cyrtocapsa cf. mastoidea, Dictyomitra sp., Eucyrtidiellum cf. unumaensis, Hsuum spp., Mirifusus mediodilatatus, Parahsuum simplum, Parvicingula sp., Spongocapsula sp., Spongosaturnalis sp., Stichocapsa cf. convexa, Stichocapsa cf. japonica, Sylingocapsa sp., Tricolocapsa cf. plicarum
• Fossils (Conodonts): Chirodella dinodoides, Cornedina ancoraeformis, Cypridodella mediocris, Cypridodella muelleri, Enantiognathus ziegleri, Epigondolella abneptis, Epidondolella bidentata, Epigondolella nodosa, Epigondolella postera, Epigondolella primitia, Neogondolella buigarica, Neogondolella excelsa?, Neogondolella foliata, Neogondolella polygnathiformis, Neohindeodella qequiramosa, Neohindeodella dropla, Neohindeodella suevica, Neopieotospathodus muelleri, Xaniognathus saginata

• Owada et al. (2014) Jour. Geol. Soc. Japan, vol.120, no.11, pp.413-418 DOI
• Kiminami et al., (2009) Jour. Geol. Soc. Japan, vol.115, no.11, pp.578-596 DOI
• Matsuura (2001) Geology of the Mitsu District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 58p. (in Japanese with English abstract 4p.)
• Matsuura et al. (1999) Geology of the Itsuku Shima District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 37p. (in Japanese with English abstract 3p.)
• Takagi and Mizuno (1999) Geology of the Kaitaichi District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 49p. (in Japanese with English abstract 4p.)
• Matsuura (1997) Geology of the Kurahashi Jima and Hashira Jima District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 53p. (in Japanese with English abstract 4p.)
• Higashimoto et al. (1986) Geology of the Otake District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 70p. (in Japanese with English abstract 6p.)
• Higashimoto et al. (1985) Geology of the Kure District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 93p. (in Japanese with English abstract 6p.)
• Higashimoto et al. (1983) Geology of the Iwakuni District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 79p. (in Japanese with English abstract 6p.)