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Izumi Group

• Coherent formation
• Izumi sedimentary basin
• Forearc basin associated with strike-slip fault related to Median Tectonic Line
• east Shikoku: Late Cretaceous, early - middle Campanian (Fossils, FT)
• west Shikoku: Late Cretaceous, late Campanian (Fossils)
• Osaka: Late Cretaceous, Maastrichtian

• Sedimentary facies: Marine
• Sedimentary facies (Main): Turbidite
• Sedimentary facies (Northern margin, Southern): non-Turbidite
• Lithofacies (Main): Interbedded sandstone and mudstone, Conglomerate, Sandstone, Mudstone
• Lithofacies (Main, Minor): Conglomerate, Felsic tuff
• Lithofacies (Northern marginal): Mudstone

• Thickness: 20,000 m or thicker
• Width: 5 - 15 km
• Length: ca. 300 km
• Upper limit: Unconformity (Osaka Group, Kuma Group, Ishizuchi Group, Syuso Formation)
• Lower limit: Unconformity (Sennan Rhyolites, Takijiri Adamellite, Ryoke Metamorphic Rocks, Ryoke Granitoids), Fault (Sennan Rhyolites)
• Southern limit: Median Tectonic Line

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

• Distribution: Kii peninsula - Awaji island - Shikoku - Kyushu

• Ikeda et al. (2017) Jour. Geol. Soc. Japan, vol.123, no.7, pp.445-470 DOI
• Seike et al. (2013) Jour. Geol. Soc. Japan, vol.119, no.12, pp.759-775 DOI
• Kano and Takagi (2013) Jour. Geol. Soc. Japan, vol.119, no.12, pp.776-793 DOI
• Kikuchi and Kotake (2013) Jour. Geol. Soc. Japan, vol.119, no.9, pp.613-629 DOI
• Seike and Hirano (2013) Jour. Geol. Soc. Japan, vol.119, no.6, pp.397-409 DOI
• Miyata et al. (2012) Jour. Geol. Soc. Japan, vol.118, Supplement, pp.37-52 DOI
• Yoshikawa et al. (2011) Jour. Geol. Soc. Japan, vol.117, no.9, pp.523-537 DOI
• Noda et al. (2010) Jour. Geol. Soc. Japan, vol.116, no.2, pp.99-113 DOI