Haa-II Tephra

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Haa-II Tephra Sawaguri and Kurokawa, 1986

Abbr.: Haa-II

Tephra
Pliocene

Lithofacies: Hornblende orthopyroxene clinopyroxene andesite, Orthopyroxene clinopyroxene andesite
Lithofacies: Pyroclastic flow deposit, Lapilli tuff
Lithofacies (Minor): Silt

Host: Hachikokusan Formation
Thickness: 80 m

Hachikokusan Formation
[ Upper ]
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Haa-II
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Silt bed
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Haa-I
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[ Lower ]

Hachikokusan region, Niigata pref.
[ Upper ]
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Hachioji Formation
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Suganuma Formation
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Hachikokusan Formation
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Hododaira Formation
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[ Lower ]

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

Distribution: Niigata pref.

Kobayashi et al. (1989) Geology of the Okanomachi District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 112p. (in Japanese with English abstract 5p.)