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Magawa Formation Maeda and Takenami, 1957

Invalid synonym: Magawa Sandstone and Conglomerate Formation, lower Higashisakamori Formation

• Type locality: Upper reaches of Magawa river, Toyama city, Toyama prefecture
• Coherent formation
• Late Jurassic, Oxfordian - Kimmeridgian (Ammonoids)

• Sedimentary facies: Marine
• Lithofacies (Upper): Sandstone, Interbedded sandstone and mudstone
• Lithofacies (Upper, Minor): Mudstone
• Lithofacies (Lower): Conglomerate
• Lithofacies (Lower, Minor): Sandy siltstone

• Thickness: 30 - 180 m or thicker
• Thickness (Upper): Several - ca. 150 m
• Thickness (Lower): ca. 30 - 60 m
• Upper limit: Conformity (Arimine Formation), Unconformity (Ioridanitoge Formation)
• Lower limit: Unconformity (Granite)

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

• Distribution: Magawa river, Toyama city, Toyama pref.; Higashisakamori valley - Inone valley - Oritate pass, Arimine, Toyama city, Toyama pref.
• Fossils (Bivalves): Myophorella (Promyophorella) hidensis Maeda and Kawabe, Myophorella (Promyophorella) toyamemsns, Nipponitrigonia kobayashii, Vaugonia ariminensis, Pinna sp.
• Fossils (Ammonoids): Discosphinctes sp., Scapnitodites? sp., Cadoceras sp.

• Matsukawa et al. (2014) Jour. Geol. Soc. Japan, vol.120, no.5, pp.147-164 DOI
• Hirasawa et al. (2010) Jour. Geol. Soc. Japan, vol.116, Supplement, pp.103-121 DOI
• Nozawa and Sakamoto (1960) Gohyakkoku, Explanatory Text of the Geological Map of Japan, Scale 1:50,000, Geological Survey of Japan, 68p. (in Japanese with English abstract 10p.)
• Kawai and Nozawa (1958) Higashimozumi, Explanatory Text of the Geological Map of Japan, Scale 1:50,000, Geological Survey of Japan, 76p. (in Japanese with English abstract 10p.)