Nagato Lavas

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Nagato Lavas (Takahashi and Nishiki, 2006) Nishiki and Takahashi, 2012

Volcanic rocks
early Pleistocene

Lithofacies: Hypersthene augite olivine basalt, Basaltic andesite
Lithofacies: Lava (2 flow units), Debris flow deposits
Lithofacies (Minor): Volcanic breccia

Eruptive volume: 7.2 km³
Thickness (Overall): 100 m or thicker
Thickness (A unit): 2 - 10 m
Upper limit: Unconformity (Karasawa Lavas, Amazakai Pyroclastic Floe Deposit)
Lower limit: Unconformity (Mochizuki Volcaniclastics, Tatamiishi Lava)

Kasuga Volcanic Rocks
[ Upper ]
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Okawaratoge Pyroclastics
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Karasawa Lavas
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Nagato Lavas
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Manitazawa Lava
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Mochizuki Volcaniclastics
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Tatamiishi Lava
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[ Lower ]

Tokin-no-iwa volcanic body
[ Upper ]
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Kasuga 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: Isuzu river - Hacchoji river, Saku city, Nagano pref.; Nagakubo, Nagawa city, Chiisagata county, 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.)