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Kamo Formation Nakao et al., 1986

Invalid synonym: Kanamaribata Formation

• Type locality: Hongo, Kamo, Minamiboso city, Chiba prefecture
• Coherent formation (1.21 - 0.78 Ma)
• Landward slope basin of trench
• early Pleistocene
• Contemporaneous heterotopic facies (Lower): upper Hata Formation
• Correlation: Oi Formation, Otadai Formation, Umegase Formation, Kokumoto Formation

• Sedimentary facies: Marine
• Lithofacies (Upper): Sandstone-dominant interbedded sandstone and tuffaceous siltstone, Conglomerate
• Lithofacies (Lower): Interbedded tuffaceous sandstone and tuffaceous siltstone

• Thickness: 200 - 300 m
• Upper limit: Unconformity (Higashinagata Formation)
• Lower limit: Unconformity (Nishizaki Formation, Hata Formation, Nagaogawa Sandstone Member)

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

• Distribution: Hongo, Kamo, Minamiboso city, Chiba pref.; Inuishi, Tateyama city, Chiba pref.
• Fossils: Shellfishes, Corals, Wood fragments, Foraminifera, Radiolarians, Diatoms, Calcareous nannofossils (Gephrocapsa sp.)
• Fossils (Foraminifera): Gephyrocapsa caribbeanica, Gephyrocapsa oceanica, Gephyrocapsa parallela, Groborotalia truncatulinoides, Pulleniatina obliquiloqulata
• Tephra: BW, MS, IC, OZ

• Utagawa et al. (2017) Jour. Geol. Soc. Japan, vol.123, no.11, pp.969-976 DOI
• Kawakami and Shishikura (2006) Geology of the Tateyama District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, AIST, 82p. (in Japanese with English abstract 5p.)
• Suzuki et al. (1990) Geology of the Nago District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 48p. (in Japanese with English abstract 3p.)