Tomarikawa Mudstone Member

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Tomarikawa Mudstone Member Matsukuma et al., 1971

Invalid synonym: Upper member of Hayaguchigawa Formation

Type locality: Tomari river, Hachimori, Happo city, Yamamoto county, Akita prefecture
Volcanic rocks
Miocene
Correlation: Nishikurosawa Formation

Sedimentary facies: Marine
Lithofacies: Mudstone
Lithofacies (Minor): Dacitic - Rhyolitic pumice tuff, Sandstone, Andesitic pyroclastic rocks

Thickness: 50 - 450 m
Lower limit: Bottom of dacitic pumice tuff-rich zone
Lower limit: Conformity (Ichinomatazawa Basalt Member)

Hayaguchigawa Formation
[ Upper ]
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Tomarikawa Mudstone Member
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Ichinomatazawa Basalt Member
'''''''/,,,,,,
Main part
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[ Lower ]

Nakahama, Akita pref.
[ Upper ]
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Onnagawa Formation
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Hayaguchigawa Formation
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Kuroishizawa Formation
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Fujikuragawa Formation
~~~~~~~~~~~~~~
[ Lower ]

Daira, Akita pref.
[ Upper ]
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Kobinaizawa Formation
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Fujikotogawa Formation
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Iwaya Formation
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Hayaguchigawa Formation
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Kuroishizawa Formation
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Fujikuragawa Formation
~~~~~~~~~~~~~~
[ Lower ]

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

Distribution: Tomari river, Hachimori, Happo city, Yamamoto county, Akita pref.; Fujikoto river, Sabizawa, Fujisato city, Yamamoto county, Akita pref.; Hayaguchi, Odate city, Akita pref.; Tazawa river, Takanosu, Kitaakita city, Akita pref.
Fossils: Shellfishes, Foraminifera
Fossils (Daijima-type flora):

Ozawa et al. (1983) Geology of the Nakahama District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 62p. (in Japanese with English abstract 4p.)
Hirayama and Sumi (1963) Takanosu, Explanatory Text of the Geological Map of Japan, Scale 1:50,000, Geological Survey of Japan, 90p. (in Japanese with English abstract 7p.)