Akebono Formation

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Akebono Formation (Otsuka, 1938) Akiyama, 1957

Invalid synonym: Akebono Group

Type locality: Oharajima - Osozawa, and Yogosawa - Hirasu, Minobu city, Minamikoma county, Yamanashi prefecture
Coherent formation
late Miocene - Pliocene

Sedimentary facies: Marine
Depth of water: Upper bathyal - Outer sublittoral
Lithofacies:

Thickness: ca. 350 - 3,800 m or thicker
Lower limit: Conformity (Karasumoriyama Volcaniclastic Member), Unconformity (Tsukimibashi Volcaniclastic Member, Hara Formation, Kuonji Formation, Takatori Volcaniclastic Rocks, Sandstone and Mudstone Member)

Akebono Formation
[ Upper ]
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Yogosawa Conglomerate Member
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Kawadaira Mudstone Member
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Osozawa Sandstone Member
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Teuchizawa Breccia Member
~~~~~~~~~~~~~~
[ Lower ]

Fujikawa Group (Central zone)
[ Upper ]
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Hamaishidake Formation / Akebono Formation
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Aimata Formation
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Kuonji Formation
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Hara Formation
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[ Lower ]

Fujikawa Group (Eastern zone)
[ Upper ]
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Akebono Formation
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Minobu Formation
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Shimobe Formation
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[ Lower ]

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

Distribution: Oharajima - Osozawa - Yogosawa - Hirasu - Oshio - Kunari - Yasaiku - Nakayama - Furuhase - Fukuhara - Nashiko - Ejirikubo - Teuchizawa - Hinataminamizawa - Aimata - Odafunahara - Minobu, Minobu city, Minamikoma county, Yamanashi pref.; Jikkoku - Yanagawa, Fujikawa city, Minamikoma county, Yamanashi pref.

Ozaki and Sugiyama (2018) Geology of the Minobu District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, AIST, 169p. (in Japanese with English abstract 7p.)