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Naradani Formation Kurata, 1940

• Type locality: Naradani valley, Sakawa city, Kochi prefecture
• Coherent formation
• Late Jurassic, Oxfordian - Kimmeridgian (Radiolarians), Kimmeridgian - Tithonian (Ammonoids)

• Sedimentary facies: Marine
• Lithofacies (Upper): Mudstone
• Lithofacies (Upper, Minor): Sandstone, Limestone blocks
• Lithofacies (Middle): Mudstone, Interbedded mudstone and sandstone
• Lithofacies (Lower): Sandstone-dominant interbedded sandstone and mudstone

• Thickness (Overall): ca. 430 m
• Thickness (Upper): ca. 140 m
• Thickness (Middle): ca. 170 m
• Thickness (Lower): ca. 120 m
• Upper limit: Partial unconformity (Torinosu Group)
• Lower limit: Thrust fault (Togano Unit)

• Distribution: Naradani valley, Sakawa city, Kochi pref.
• Fossils: Echinoids, Gastropods, Crinoids, Solitary corals, Plants, Radiolarians
• Fossils (Ammonoids): Aspidoceras sp., Hybonoticeras sp.
• Fossils (Bivalves): Corbula globosa, Nuculana (Dacryomya) stenodolichos, Nuculana (Praesaccella) erinoensis, Nuculana (Praesaccella) yatsushiroensis, Grammatodon (Grammatodon) takiensis, Protocardia tosensis, Opis (Trigonopsis) torinosuensis, Parallelodon koikensis
• Fossils (Brachiopods): Rhynchonella tamurai
• Fossils (Limestone): Rhynchonella tamurai, Echinoids (Needles)

• Maeda et al. (2012) Jour. Geol. Soc. Japan, vol.118, no.11, pp.741-747 DOI