Kumeji Pyroclastic Member

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Kumeji Pyroclastic Member Saito, 1961

Type locality: Kumeji bridge, Shinshushinmachi town, Nagano city, Nagano prefecture
Volcanic rocks
Pliocene
Correlation: lower Arakurayama Formation, Hijiriyama Andesite

Sedimentary facies: K-rich high-alumina basalt
Sedimentary facies (Minor): Hyaloclastite
Lithofacies: Anesite - Basalt volcanic breccia, Tuff breccia
Lithofacies (Minor): Lava, Volcanic conglomerate, Mudstone

Thickness: 10 - 350 m
Upper limit: Unconformity (Akada Formation, Haibara Formation, Ooka Mudflow Deposit)

Joshita Member
[ Upper ]
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Kumeji Pyroclastics Member
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[ Lower ]

(Invalid name) Shigarami Formation (Togakushi, Nagano pref.)
[ Upper ]
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Ogikubo Sandy Mudstone Member
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Arakurayama Pyroclastic Member
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Takafu Mudstone Member
'''''''/,,,,,,
Gonda Sandstone Conglomerate Member
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[ Lower ]

(Invalid name) Shigarami Formation (Nagano, Nagano pref.)
[ Upper ]
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Ogikubo Sandy Mudstone Member
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Arakurayama Pyroclastic Member / Hirose Mudstone Member / Joshita Member
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Okubo Mudstone and Sandstone Member
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[ Lower ]

(Invalid name) Shigarami Formation (Komiji, Nagano pref.)
[ Upper ]
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Joshita Member
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Nagaiwa Member
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[ Lower ]

(Invalid name) Shigarami Formation (Hikage, Nagano pref.)
[ Upper ]
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Tanogashira Member
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Idoirisawa Member
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Hiratokosawa Member
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[ Lower ]

Hokushin Group
[ Upper ]
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Shigarami Formation
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Ogawa Formation
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Aoki Formation
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[ Lower ]

northern Nagano pref.
[ Upper ]
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Hokushin Group
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Chushin Group
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[ Lower ]

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

Distribution: Kumeji bridge - Mount Kokuzo - Kamisamizu - Shiomoto - Takahagi - Hirashimizu - Nakahara - Ikeda - Mount Iizuna - Misuzu bridge, Shinshushinmachi town, Nagano city, Nagano pref.; Sasadaira dam - Yokezawa creek, Naniai, Nagano city, Nagano pref.; Ashinuma - Shimokurio, Ooka, Nagano city, Nagano pref.; Kamiikari, Nakajo, Nagano city, Nagano pref.

Kato et al. (1989) Geology of the Omachi District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 111p. (in Japanese with English abstract 7p.)
Kato and Akahane (1986) Geology of the Nagano District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 120p. (in Japanese with English abstract 5p.)