Kyowa-bokujo Lavas

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Kyowa-bokujo Lavas

Volcanic rocks
early Pleistocene (1.4 Ma, K-Ar)

Lithofacies: Andesite
Lithofacies: Lavas (3 flow units)
Lithofacies (Minor): Pyroclastic rocks

Source: West of Mount Tateshina
Eruptive volume: 0.6 km³
Thickness: 40 m or thicker
Thickness (A unit): 10 - 20 m
Lower limit: Unconformity (Amazakai Pyroclastic Flow Deposit, Kasuga Volcanic Rocks)

Nijinotaira Volcanic Rocks
[ Upper ]
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Ryugamine Lavas
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Kyowa-bokujo Lavas
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Uyamasegi Lava
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[ Lower ]

Ryugamine volcanic body
[ Upper ]
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Nijinotaira Volcanic Rocks
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[ Lower ]

Yabashira volcanoes
[ Upper ]
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Kengamine volcanic body
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Byobuiwa volcanic body
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Yabashirayama volcanic body
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Ryugamine volcanic body
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Tokin-no-iwa volcanic body
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[ Lower ]

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

Distribution: 1,000 - 1,400 m above sea level, Higashizawa - Asadagiri, Kyowa, Saku city, Nagano pref.; Kakuma river - Karasawa - Hacchoji river - Akatani - Kasugayuzawa, Saku city, Nagano pref.

Nishiki and Takahashi (2012) Jour. Geol. Soc. Japan, vol.118, no.8, pp.499-515 DOI
Kawachi and Aramaki (1979) Geology of the Komoro District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 39p. (in Japanese with English abstract 2p.)
Kawachi (1974) Geology of the Tateshinayama District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 114p. (in Japanese with English abstract 5p.)