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Kodama Formation Watabe et al., 1950

• Coherent formation
• middle Miocene (Foraminifera)
• Correlation: Ushibuse Formation - Niwaya Formation?, upper Kozono Formation - Ichinokawa Formation?

• Lithofacies (Upper): Siltstone, Tuffaceous siltstone, Tuffaceous sandstone, Acidic tuff
• Lithofacies (Middle): Tuffaceous sandstone
• Lithofacies (Lower): Siltstone
• Lithofacies (Bottom): Sandstone
• Lithofacies (Bottom, Minor): Siltstone, Conglomerate, Lignite

• Thickness (Upper): ca. 300 m or thicker
• Thickness (Upper, Acidic tuff): ca. 50 m or thicker
• Thickness (Middle - Bottom): ca. 500 m or thicker
• Upper limit: Unconformity (Middle II Terrace Deposit)

• Distribution: Misato city, Kodama county, Saitama pref.
• Fossils: Shellfishes (Nuculana sp.)
• Fossils (Foraminifera): Miogypsina sp., Nephrolepidina sp., Operculina sp.

• Makimoto and Takeuchi (1992) Geology of the Yorii District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 136p. (in Japanese with English abstract 6p.)