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Itoman Formation Kaneko and Ito, 2006

• Type locality: Yamagusuku, Itoman city, Okinawa prefecture
• Coherent formation
• Coral reef complex
• Pleistocene (1.65 - 1.21 Ma, Calcareous nannofossils)
• Contemporaneous heterotopic facies: Subunit 1R, Naha Formation

• Sedimentary facies: Marine
• Depth of water: Shallow
• Depth of water: Middle - deep reef slope (20 - 50 m)
• Lithofacies (Main): Coralline algae limestone
• Lithofacies (Minor): Algal ball limestone, Clastic limestone, Gravelly limestone, Calcareous conglomerate

• Thickness: 2 m or thicker
• Upper limit: Partly unconformity (Naha Formation)
• Lower limit: Unconformity (Shimajiri Formation)

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

• Distribution: Yamagusuku - Minaminamihira - Uegusuku - Cape Kyan - Nashiro, Itoman city, Okinawa pref.
• Distribution: Hyakunodai - Isaneku - Kamikatetsu, Kikai island, Kagoshima pref.
• Fossils (Coralline algae): Lithophyllum prototypum, Spongites sp., Neogoniolithon fosliei, Mesophyllum erubescence

• Sagae et al. (2012) Jour. Geol. Soc. Japan, vol.118, no.2, pp.117-136 DOI