Yarimi Tuff Member

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Yarimi Tuff Member

Volcanic rocks
Late Cretaceous (ca. 63 Ma, Rb-Sr)

Sedimentary facies: Subaqueous
Lithofacies: Rhyolite tuffaceous sandstone, Tuffaceous mudstone, Lapilli tuff, Tuff breccia, Conglomerate
Lithofacies (Minor): Andesite - Dacite tuff, Accretionary lapilli tuff
Sedimentary structures: Parallel stratification

Thickness: 40 - 230 m
Upper limit: Interfingered
Lower limit: Conformity (Nakao Tuff Member), Unconformity (Horatani Tonalite, Tochio Formation)

Kasadani Formation
[ Upper ]
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Upper lava
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Kuriyadani Welded Tuff Member
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Lower lava
'''''''/,,,,,,
Yarimi Tuff Member
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[ Lower ]

Kasagatake Rhyolites
[ Upper ]
~~~~~~~~~~~~~~
Kasagatakesancho Welded Tuff
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Anagedani Formation
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Kasadani Formation
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Nakao Formation
~~~~~~~~~~~~~~
[ Lower ]

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

Distribution: Kuriyadani valley - Gamata - Kasadani valley - Yarimi - Karukaya, Okuhidaonsengo, Takayama city, Gifu pref.
Fossils: Wood fragments

Harayama (1990) Geology of the Kamikochi District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 175p. (in Japanese with English abstract 11p.)