Unit IV

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Unit IV

Volcanic rocks
Holocene

Lithofacies: Clinopyroxene-bearing orthopyroxene hornblende dacite, Clinopyroxene orthopyroxene hornblende andesite
Lithofacies: Scoria lapilli (A fall unit)
Lithofacies: Andesite lapilli, Volcanic ash
Sedimentary structures: Reversed graded bedding

Mode of eruption: Plinian
Eruptive volume: ca. 0.05 km³ DRE

Numazawako Pyroclastic Deposit
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Unit IV
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Unit III
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Unit II
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Unit I = Numazawa-Numazawako Pyroclastic Flow Deposit
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[ Lower ]

Numazawa volcano
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Numazawako Pyroclastic Deposit / Numazawako Lahar Deposit
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Numagozen Pyroclastic Deposit
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Maeyama Lava
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Sozan Lava
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Mizunuma Pyroclastic Deposit
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Mukurezawa Lava
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Shirifukitoge Pyroclastic Deposit / Nm-SB Tephra
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------ Conformity, ~~~~~~ Unconformity, ~~~--- Local unconformity, '''/,, Interfingered, :::::: Fault, /--/-- Thrust, +__+__ Ground surface, ?--?-- Unknown

Distribution: Lake Numazawa - Tadami river, Aizu basin, Fukushima pref.

Masubuchi and Ishizaki (2011) Jour. Geol. Soc. Japan, vol.117, no.6, pp.357-376 DOI
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 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.)