Osozawa Sandstone Member

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Osozawa Sandstone Member (Akiyama, 1957) Ozaki and Sugiyama, 2018

Invalid synonym: Osozawa Formation, Shizukawa Formation

Type locality: Oharajima, Awakura, Minobu city, Minamikoma county, Yamanashi prefecture
Coherent formation
late Miocene (Foraminifera, Bivalves)

Sedimentary facies: Marine
Sedimentary facies: Narrow continental shelf, Steep continental slope
Sedimentary facies: Shallow marine including gravelly shore, Continental slope - Deep sea
Sedimentary facies: Trough-fill deposit in the transgressive stage
Climate: Tropical - Subtropical
Lithofacies (Upper): Siltstone, Sandstone
Lithofacies: Sandstone
Lithofacies (Minor): Coquina (Coquinoid limestone)
Lithofacies (Basal, Minor): Conglomerate

Thickness: ca. 20 - 100 m
Upper limit: Conformity (Kawadaira Mudstone Member, Yogosawa Conglomerate Member)
Lower limit: Conformity (Karasumoriyama Volcaniclastic Member), Unconformity (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: Awakura - Nashiko - Ejirikubo - Osozawa - Yokaichiba, Minobu city, Minamikoma county, Yamanashi pref.
Fossils: Whales, Coral algae, Corals, Bryozoans, Brachiopods
Fossils (Zushi fauna): Amussiopecten iitomiensis, Callista chinensis, Chlamys kakisakiensis, Chlamys miurensis, Fissidentalium yokoyamai, Ginebis argenteonitens, Glycymeris cisshuensis, Glycymeris osozawaensis, Glycymeris rotunda, Keenaea samarangae, Megacaardita panda, Turbo cf. marmoratus

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.)