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Naradate Formation Noda, 1962

Invalid synonyms: Doro Formation, Hishigatake Volcanic Rocks, Nonomigawa Volcanic Rocks

• Type locality: Naradate, Tokamachi city, Niigata prefecture
• Coherent formation
• Rift basin sediments
• late Pliocene (3 Ma or later)
• Correlation: lower Uonuma Formation, Ogawa Formation, Nakajogawa Member
• Correlation (Lower): upper Uragawara Formation
• Intruded by: Augite hypersthene andesite, Hypersthene andesite

• Sedimentary facies (Upper): Terrestrial
• Sedimentary facies (Middle): Fluvial
• Sedimentary facies (Middle, Minor): Brackish
• Sedimentary facies (Lower): Fluvial
• Sedimentary facies (Lower, Minor): Brackish
• Lithofacies (Upper): Pyroxene andesite lava, Volcanic breccia
• Lithofacies (Upper, Minor): Tuff
• Lithofacies (Middle): Sandstone, Siltstone
• Lithofacies (Middle, Minor): Conglomerate, Lignite, Acidic tuff
• Lithofacies (Lower): Sandstone
• Lithofacies (Lower, Minor): Conglomerate

• Thickness: 900 m or thicker
• Thickness (Upper): 400 m or thicker
• Thickness (Middle): 300 - 800 m
• Thickness (Lower): 55 - 120 m
• Upper limit: Conformity (Saruhashi Conglomerate Member)
• Lower limit: Conformity (Shiroiwa Formation)

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

• Distribution: Naradate, Tokamachi city, Niigata pref.; Mount Hishigatake - Mount Maeyama, Joetsu city, Niigata pref.
• Fossils: Shellfishes, Ostrea sp., Trace fossils

• Takano (2011) Jour. Geol. Soc. Japan, vol.117, no.4, pp.238-258 DOI
• Takeuchi and Kato (1994) Geology of the Takada-tobu District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 67p. (in Japanese with English abstract 5p.)