Komatsubara Tuff

[ Top ] [ Japanese ]

Komatsubara Tuff Akahane, 1980

Tephra
late Miocene

Lithofacies (Top): Rhyolite lava
Lithofacies (Top, Minor): Obsidian, Pitch stone, Perlite
Lithofacies: Rhyolitic tuff, Lapilli tuff
Lithofacies (Minor): Tuff breccia

Thickness: 40 - 300 m

Lower Susobana Tuff Member
[ Upper ]
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Hotama Tuff
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Nashikubo Sandstone and Conglomerate
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Hanakami Tuff Breccia
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Shinbashi Pumice Tuff
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Hotokezawa Tuff
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Takizawa Dacite Tuff
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Nakaoyama Rhyolite Lava
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Saizawa Pumice Tuff
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Komatsubara Tuff
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Koichi Dacite Tuff
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[ Lower ]

Togakushi (East), Nagano pref.
[ Upper ]
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Ronji Formation
~~~~~~~~~~~~~~
Susobana Formation
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Asakawa Formation
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Nishikyo Formation
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[ Lower ]

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

Distribution: Koichi - Nakaoyama - Saizawa, Nagano city, Nagano pref.

Kato and Akahane (1986) Geology of the Nagano District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 120p. (in Japanese with English abstract 5p.)