Ashikawa Formation

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Ashikawa Formation

Type locality: Yamanashi prefecture
Volcanic rocks
Miocene
Contemporaneous heterotopic facies: Ichinose Formation

Lithofacies: Tholeiitic (Pigeonite series)
Lithofacies: Basalt
Lithofacies (Minor): Mudstone, Tuff

Upper limit: Conformity, partly interfingered (Ichikawadaimon Formation, Kawaguchi Formation)

Ashigawa Formation (West)
[ Upper ]
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Yamaho Mudstone and Tuff Member
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Kurosawa Basalt and Mudstone Member
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[ Lower ]

Ashigawa Formation (East)
[ Upper ]
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Takahagi Basalt Member
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Orikado Basalt and Mudstone Member
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[ Lower ]

Nishiyatsushiro Group (western Kofu, Yamanashi pref.)
[ Upper ]
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Kawaguchi Formation
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Ashigawa Formation / Ichinose Formation
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[ Lower ]

Nishiyatsushiro Group (eastern Kofu, Yamanashi pref.)
[ Upper ]
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Ichikawadaimon Formation
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Ashigawa Formation
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[ Lower ]

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

Distribution: Mount Kenashi, Yamanashi pref.

Nagahata et al. (2015) Jour. Geol. Soc. Japan, vol.121, no.4, pp.141-146, DOI
Katada (1956) Kofu, Explanatory Text of the Geological Map of Japan, Scale 1:50,000, Geological Survey of Japan, 27p. (in Japanese with English abstract 4p.)