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Josoji Formation

• Coherent formation
• Submarine volcano by the felsic volcanisum
• early - middle Miocene (16 - 14 Ma)

• Sedimentary facies: Marine
• Depth of water: Continental margin - Continental slope (Foraminifera)
• Depth of water: Bathyal (Foraminifera)
• Lithofacies: Shale
• Lithofacies (Minor): Rhyolitic lava, Rhyolitic pyroclastic rocks, Basalt, Andesite
• Sedimentary structures: Slump structures

• Thickness: 1,600 m
• Thickness (Northwest): 600 m
• Upper limit: Interfingered (Aishiro Formation)
• Lower limit: Conformtiy (Koura Formation)
• Lower limit: Bottom of black shale dominated beds of Josoji Formation

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

• Distribution: Shimane peninsula, Shimane pref.
• Distribution: Hoda, Mihonoseki village, Matsue city, Shimane pref.
• Fossils: Bivalves (Portlandia sp., Acesta sp.), Foraminifera
• Deposits: Wanibuchi mine, Utouge mine, Sagi mine

• Kano (2018) Jour. Geol. Soc. Japan, vol.124, no.10, pp.781-803 DOI
• Nomura et al. (2018) Jour. Geol. Soc. Japan, vol.124, no.2, pp.95-109 DOI
• Sakai et al. (2013) Jour. Geol. Soc. Japan, vol.119, no.4, pp.285-299 DOI
• Sato et al. (2011) Jour. Geol. Soc. Japan, vol.117, no.8, pp.439-450 DOI
• Tanaka and Nomura (2009) Jour. Geol. Soc. Japan, vol.115, no.6, pp.261-265 DOI
• Utada (2007) Jour. Geol. Soc. Japan, vol.113, no.8, pp.438-453 DOI