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Takatama Formation (Seki, 1994) Sakaguchi, 1995 (Photo)

Invalid synonym: Harase Formation

• Type locality: Takatama, Koriyama city, Fukushima prefecture
• Volcanic rocks
• Takatama caldera fill sediments
• Miocene (8.4, 8.2 Ma, K-Ar)
• Intruded by: Onagurayama Andesite

• Sedimentary facies (Post-caldera-stage volcanic rocks): Submarine lava dome
• Lithofacies (Post-caldera-stage volcanic rocks): Rhyolite, Andesite
• Lithofacies (Post-caldera-stage volcanic rocks, Minor): Dacite
• Lithofacies (Post-caldera-stage caldera lake-fill deposit): Sandstone, Conglomerate, Siltstone
• Lithofacies (Post-caldera-stage caldera lake-fill deposit, Minor): Pumice tuff
• Sedimentary structures (Post-caldera-stage caldera lake-fill deposit): Graded bedding

• Thickness (Post-caldera-stage caldera lake-fill deposit): ca. 800 m
• Thickness (Caldera-forming stage pyroclastic flow deposit): 350 m or thicker
• Upper limit: Unconformity (Onagurayama Andesite)
• Lower limit: Unconformity (Biotite granite, Muscovite biotite granite)

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

• Distribution: Takatama, Koriyama city, Fukushima pref.

• Sakaguchi (1995) Geology of the Nihonmatsu District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 79p. (in Japanese with English abstract 4p.)