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Nashino Formation (Kitamura, 1967) Kitamura et al., 1986

Invalid synonym: Nashino Tuff Formation

• Type locality: Nashino - western foot of Mount Taihaku, Sendai city, Miyagi prefecture
• Coherent formation
• East margin of Shirasawa caldera
• late Miocene (6.4 Ma, FT)
• Intruded by: Andesite

• Sedimentary facies: Terrestrial
• Sedimentary facies: Pyroclastic flow
• Lithofacies: Sandstone, Pumice tuff, Sandy tuff
• Sedimentary facies (Upper, Minor): Lignite
• Sedimentary structures: Cross-stratification, Slump structures

• Thickness: 0 - ca. 120 m
• Upper limit: Conformity (Shirasakatoge Siltstone Member), Partly interfingered (Mitaki Formation), Unconformity (Kameoka Formation)
• Lower limit: Unconformity (Yumoto Formation, Tsunaki Formation, Hatatate Formation, Moniwa Formation, Takadate Formation)

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

• Distribution: Nashino - Mount Taihaku - Tsunaki - Hirose river, Ishiyama, Sendai city, Miyagi pref.; Mount Naraibanzan, Aoba ward, Sendai city, Miyagi pref.
• Fossils: Silicified wood

• Miyamoto et al. (2013) Jour. Geol. Soc. Japan, vol.119, Supplement, pp.27-46 DOI
• Fujiwara et al. (2013) Jour. Geol. Soc. Japan, vol.119, Supplement, pp.96-119 DOI
• Kitamura et al. (1986) Geology of the Sendai District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 134p. (in Japanese with English abstract 9p.)