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Komatsuji Formation (Hattori et al., 1983) Kano et al., 2001

Invalid synonym: Mimata Subgroup, Komatsuji Dacite

• Type locality: Komatsuji, Misato city - Kawauchi, Kawamoto city, Ochi county, Shimane prefecture
• Volcanic rocks
• late Oligocene (ca. 30 Ma; 29.8 - 18.4 Ma, FT; 18.9 Ma, K-Ar)
• Intruded by: Minamiyama Dikes, Makihara Complex, Dacite lava domes (3 lava domes)

• Lithofacies: Pyroclastic flow deposit
• Lithofacies: Dacite welded tuff
• Lithofacies (Minor): Pumiceous lapilli tuff, Tuff
• Lithofacies (Lava dome): Dacite lava

• Thickness: ca. 400 - 800 m
• Distribution (Diamter, Lava dome): 0.5 - 2 km
• Upper limit: Unconformity (Toburodani Formation, Hata Formation, Tsunozu Group)
• Lower limit: Unconformity (Kotani Formation)

------ Transitional, ~~~~~~ Intrusive, :::::: Fault, /--/-- Thrust, +__+__ Ground surface, ?--?-- Unknown

• Distribution: Minakami town - Ichiba, Oda city, Shimane pref.; Kawauchi - Kotani - Kitasaki, Kawamoto city, Ochi county, Shimane pref.; Komatsuji - Toburodai - Kyoranbara - Tashirodani - Kogaidani - Taheidani?, Misato city, Ochi county, Shimane pref.

• Kano (2018) Jour. Geol. Soc. Japan, vol.124, no.10, pp.781-803 DOI
• Kano et al. (2001) Geology of the Yunotsu and Gotsu District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 129p. (in Japanese with English abstract 5p.)
• Kano et al. (1998) Geology of the Iwami-Oda and Oura District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 118p. (in Japanese with English abstract 5p.)
• Hattori et al. (1983) Geology of the Sambesan District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 168p. (in Japanese with English abstract 7p.)