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Negoya Formation Kobayashi et al., 1955

• Type locality: Negoya valley, Asahi city, Shimoniikawa county, Toyama prefecture
• Coherent formation
• Early Jurassic, Pliensbachian
• Correlation: Yoshinazawa Formation

• Sedimentary facies: Marine
• Lithofacies: Mudstone
• Lithofacies (Minor): Conglomerate, Sandstone, Interbedded sandstone and mudstone, Felsic tuff
• Sedimentary structures: Cross stratification, Parallel stratification, Ripple marks, Bioturbation

• Thickness: ca. 1,000 m
• Upper limit: Conformity (Teradani Formation)
• Lower limit: Conformity (Bottom of the thick sandstone bed of Aisawadani Member)
• Lower limit: Conformity (Kitamatadani Formation)

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

• Distribution: Negoya valley - Kawakurodani valley, Asahi city, Shimoniikawa county, Toyama pref.; Mount Kikuishiyama - Mount Inugatake, Asahi city, Shimoniikawa county, Toyama pref. - Itoigawa city, Niigata pref.; Aisawadani valley - Sakaigawa river - Mount Shibakurayama, Itoigawa city, Niigata pref.
• Fossils: Ammonoids, Shellfishes (Bakevellia sp.)

• Takeuchi et al. (2017) Jour. Geol. Soc. Japan, vol.123, no.5, pp.335-350 DOI
• Takeuchi et al. (2017) Geology of the Tomari District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, AIST, 121p. (in Japanese with English abstract 4p.)
• Takeuchi et al. (2015) Jour. Geol. Soc. Japan, vol.121, no.7, pp.193-216, DOI
• Nagamori et al. (2010) Geology of the Kotaki District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, AIST, 130p. (in Japanese with English abstract 4p.)