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Shiroumadake Formation Takeuchi et al., 2001

• Type locality: Mount Asahidake, Kurobe city, Toyama prefecture - Hakuba city, Kitaazumi county, Nagano prefecture - Mount Shozudake, Omachi city, Nagano prefecture
• Coherent formation
• Permian (Radiolarians)
• Intruded by: Hornblende gabbro, Ariake Granite
• Correlation: Kotaki Formation

• Lithofacies (Upper): Felsic tuff, Tuff breccia, Siliceous tuff
• Lithofacies (Upper, Minor): Limestone breccia, Basalt
• Lithofacies (Middle): Mudstone
• Lithofacies (Middle, Minor): Sandstone
• Lithofacies (Lower): Felsic pyroclastic rocks
• Lithofacies (Lower, Minor): Basalt pillow lava

• Thickness: 500 m or thicker
• Upper limit: Thrust fault (Oeyama Ophiolite)

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

• Distribution: Mount Asahidake - Mount Shirouma - Mount Shiouma-Yarigatake, Kurobe city, Toyama pref. - Hakuba city, Kitaazumi county, Nagano pref.; Mount Shozudake, Omachi city, Nagano pref.; Mount Nagatsugayama, Asahi city, Shimoniikawa county, Toyama pref. - Itoigawa city, Niigata pref.; Mount Gorinyama - Odokorogawa river - Mount Yukikuradake, Itoigawa city, Niigata pref.
• Fossils (Radiolarians): Albaillella asymmetrica, Follicucullus porrectus, Pseudoalbaillella scarprata
• Fossils (Limestone gravels, Devonian from Hida Marginal Belt): Corals

• Takeuchi et al. (2017) Geology of the Tomari District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, AIST, 121p. (in Japanese with English abstract 4p.)
• Nagamori et al. (2010) Geology of the Kotaki District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, AIST, 130p. (in Japanese with English abstract 4p.)
• Machi and Ishiwatari (2010) Jour. Geol. Soc. Japan, vol.116, no.6, pp.293-308 DOI
• Nakano et al. (2002) Geology of the Shiroumadake District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, AIST, 105p. (in Japanese with English abstract 5p.)