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Nagurasawa Pyroclastic Flow Deposit

• Volcanic rocks
• Caldera-overflow pyroclastic deposit
• early Pleistocene (1.2 - 1.0 Ma; 1.19 Ma, FT)
• Intruded by: Basalt dikes

• Lithofacies: Pyroclastic flow deposit
• Lithofacies: Hornblende orthopyroxene clinopyroxene dacite lapilli tuff
• Lithofacies (Minor): Tuff breccia

• Source: Tonohetsuri caldera
• Host: Nanaorezaka Formation
• Thickness: ca. 200 m
• Lower limit: Conformity (Lacustrine deposit, Kasshi Volcanic Rocks)

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

• Distribution: Yagoshima - Nagurasawa - Mount Kannon, Shimogo city, Minamiaizu county, Fukushima pref.; Futamata, Tenei city, Iwase county, Fukushima pref.

• Yamamoto et al. (2006) Geology of the Kitakata District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, AIST, 63p. (in Japanese with English abstract 5p.)
• Yamamoto (1999) Geology of the Tajima District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 85p. (in Japanese with English abstract 8p.)