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Mizunuma Pyroclastic Deposit (Takahashi and Sugawara, 1985) Yamamoto, 1995

Invalid synonym: Mizunuma-Kaneyama Tephra

• Type locality: Tadami river, Mizunuma, Kaneyama city, Onuma county, Fukushima prefecture
• Volcanic rocks
• Pleistocene (53 ka)

• Sedimentary facies (Unit I): Phreatic eruption deposit
• Sedimentary facies (Unit III): Pyroclastic flow deposit
• Lithofacies: Biotite cummingtonite hornblende dacite
• Lithofacies (Unit I): Fall deposit
• Lithofacies (Unit II): Pumiceous lapilli fall deposit
• Sedimentary structures (Unit II): Reversed graded bedding

• Thickness (Unit I): A few - 40 cm or thicker
• Thickness (Unit II): ca. 16 cm - 1 m or thicker
• Thickness (Unit III): 100 m or thinner
• Lower limit (Unit II): Unconformity (Middle Terrace Deposit)

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

• Distribution: Lake Numazawa, Kaneyama city, Onuma county, Fukushima pref.; Tadami river, Mizunuma, Kaneyama city, Onuma county, Fukushima pref.; Kanozu, Tadami city, Minamiaizu county, Fukushima pref.; Yunohira - Hayato, Mishima city, Onuma county, Fukushima pref.

• Masubuchi et al. (2016) Jour. Geol. Soc. Japan, vol.122, no.10, pp.533-550, DOI
• Yamamoto and Hasebe (2014) Jour. Geol. Soc. Japan, vol.120, no.1, pp.1-9 DOI
• Masubuchi and Ishizaki (2011) Jour. Geol. Soc. Japan, vol.117, no.6, pp.357-376 DOI
• Yamamoto and Komazawa (2004) Geology of the Miyashita District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, AIST, 71p. (in Japanese with English abstract 5p.)