Sanuki Mudstone Member

Type locality: Sanuki, Futtsu city, Chiba prefecture
Coherent formation
Fore-arc basin sediments (Kazusa trough)
Pleistocene
Contemporaneous heterotopic facies: Sunami Sandstone Member

Lithofacies: Mudstone
Lithofacies (Minor): Sandstone, Sandy mudstone, Muddy sandstone
Sedimentary structures (Bottom): Slump structures

Upper limit: Unconformity (Jizodo Formation)

Kasamori Formation (North)
[ Upper ]
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Kouri Sand Member
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Yoro Sand Member
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[ Lower ]

Kasamori Formation (South)
[ Upper ]
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Sanuki Mudstone Member / Sunami Sandstone Member
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Nagahama Sand and Gravel Member
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[ Lower ]

Kazusa Group (central Boso peninsula)
[ Upper ]
~~~~~~~~~~~~~~
Kasamori Formation / Kongochi Formation
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Mandano Formation
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Chonan Formation
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Ichijiku Formation
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Kakinokidai Formation
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Kokumoto Formation
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Umegase Formation
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Otadai Formation
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Kiwada Formation
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Ohara Formation
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Namihana Formation
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Katsuura Formation
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Kurotaki Formation
~~~~~~~~~~~~~~
[ Lower ]

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

Distribution: Sanuki, Futtsu city, Chiba pref.
Fossils: Mammals (Parelephas trogontherii)
Tephra: Ks5, Ks10, Kb-Ks, Ks115A, Ks115B

Nakajima and Watanabe (2005) Geology of the Futtsu District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, AIST, 102p. (in Japanese with English abstract 8p.)