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Maizuru Group

• Type locality: Maizuru city, Kyoto prefecture
• Lower: Back-arc basin
• Coherent formation
• early - late Permian (Radiolarians)
• Correlation: Karita Formation, Hachimandai Formation, Yoshiwa Group
• Intruded by: Maizuru Granite, Biotite rhyolite instrusive breccia

• Sedimentary facies: Marine
• Lithofacies (Upper): Shale
• Lithofacies (Upper, Minor): Sandstone
• Lithofacies (Middle): Sandstone, Siltstone, Shale
• Lithofacies (Middle, Minor): Conglomerate
• Lithofacies (Lower): Shale
• Lithofacies (Lower, Minor): Limestone, Greenstones, Sandstone
• Sedimentary structures (Lower): Slump structures

• Thickness: 1,500 m or thicker
• Thickness (Upper): 100 - 400 m
• Thickness (Middle): 800 m or thicker
• Thickness (Lower): 400 m or thinner
• Distribution (East - West): ca. 4 km
• Upper limit: Unconformity (Narahara Formation, Nabae Group, Fukumoto Group, Uchiura Group, Yakuno Group)

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

• Distribution: Hyogo pref. - Kyoto pref. - Fukui pref.
• Distribution: Mount Aobasan - Nabae - Ogurui, Takahama city, Oi county, Fukui pref.; Shidaka - Hatta - Okawa - Nanukaichi - Bessho - Shiratori pass - Shikahara - Ikebe - Sugasaka pass - Isazugawa river, Maizuru city, Kyoto pref.; Toyosato - Hirobatake - Akamezaka - Shigasato Nishizaka - Murootani - Monobe, Ayabe city, Kyoto pref.; Hazumaki - Shimoamazu - Shimoochi - Kawahigashi - Komori, Fukuchiyama city, Kyoto pref.
• Fossils: Trilobites (Pseudophyllipsia sp.), Ammonoids, Crinoids, Radiolarians, Corals (Siphonodendron nakazawai, Waagenophyllum sp.), Bryozoans (Batostomella sp., Fenestella? sp., Fustilipora sp.), Calcareous algae
• Fossils (Kawahigashi fauna, Brachiopods): Aulosteges dalhousi, Chonetina matsushitai, Chonetina substrophomenoides, Derbyia altestriata, Derbyia cf. grandis, Derbyia hemisphaerica var. radiata, Eolyttonia nakazawai, Hustedia grandicosta, Hustedia indica, Lamnimargus japonicus, Linoproductus interruptus, Linoproductus kiangsiensis, Lissochonetes cf. avicula, Lissochonetes bipartita, Lissochonetes morahensis, Megousia sp., Productus (Dictyoclostus) gratiosus, Productus (Dictyoclostus) cf. margaritatus
• Fossils (Bivalves): Aviculopecten sp., Pleurophorus sp.
• Fossils (Fusulinids): Codonofusiella cf. cuniculata, Fusulinella sp., Lepidolina kumaensis, Lepidolina toriyamai, Lepidolina triyamai maizurensis, Neoschwagerina cf. douvillei, Neoschwagerina margaritae, Neoschwagerina cf. simplex, Parafusulina? sp., Pseudodoliolina pseudolepida gravitesta, Reichelina matsushitai, Schubertella? sp., Schwagerina aff. acris, Sumatrina sp., Yabeina columbiana, Yabeina gubleri, Yabeina yasubaensis

• Suda and Hayasaka (2009) Jour. Geol. Soc. Japan, vol.115, no.6, pp.266-287 DOI
• Takemura et al. (2009) Jour. Geol. Soc. Japan, vol.115, Supplement, pp.123-137 DOI
• Kurimoto and Makimoto (1990) Geology of the Fukuchiyama District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 97p. (in Japanese with English abstract 5p.)
• Igi and Kuroda (1965) Oeyama, Explanatory Text of the Geological Map of Japan, Scale 1:50,000, Geological Survey of Japan, 81p. (in Japanese with English abstract 12p.)
• Igi et al. (1961) Maizuru, Explanatory Text of the Geological Map of Japan, Scale 1:50,000, Geological Survey of Japan, 49p. (in Japanese with English abstract 9p.)
• Hirokawa and Kuroda (1958) Tangoyura, Explanatory Text of the Geological Map of Japan, Scale 1:50,000, Geological Survey of Japan, 23p. (in Japanese with English abstract 9p.)
• Hirokawa and Kuroda (1957) Nokogirizaki, Explanatory Text of the Geological Map of Japan, Scale 1:50,000, Geological Survey of Japan, 22p. (in Japanese with English abstract 9p.)