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Nakazato Formation Otsuka, 1937

• Type locality: Kaminakazato, Isogo ward, Yokohama city, Kanagawa prefecture
• Coherent formation
• Fore-arc basin sediments (Kazusa trough)
• Interfingered (Lower): Koshiba Formation
• Correlation: Kakinokidai Formation, upper Kokumoto Formation

• Sedimentary facies: Tidal zone, Shallow marine, Lower sublittoral
• Depth of water: 20 - 30 m (Shellfishes)
• Lithofacies: Sandy mudstone

• Thickness: 60 - 200 m
• Upper limit: Conformity (Hama Formation), Unconformity (Nakazato Formation)
• Lower limit: Transitional (Koshiba Formation, Kamihoshikawa Formation)

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

• Distribution: Kaminakazato, Isogo ward, Yokohama city, Kanagawa pref.
• Fossils (Shellfishes): Nassarius gemmulatus
• Tephra: Sh, Ki, My1, My2, Nm, Ku2A, Ka2.3, Ka2.4

• Suzuki and Murata (2011) Jour. Geol. Soc. Japan, vol.117, no.7, pp.379-397 DOI
• Mitsunashi and Kikuchi (1982) Geology of the Yokohama District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 105p. (in Japanese with English abstract 4p.)