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Higashinagano Formation Kobayashi, 1926

• Coherent formation
• Early Jurassic, Sinemurian - Pliensbachian (Ammonoids)

• Sedimentary facies: Shallow marine
• Sedimentary facies: Transgressive deposits
• Sedimentary facies (Top): Transgressive lag
• Sedimentary facies (Bottom): Talus of debris flow, Slope apron
• Depth of water (Top): Outer shelf (deeper than storm wave base)
• Depth of water (Middle): Inner shelf (fair-weather wave base - storm wave base)
• Depth of water (Low): Outer shelf (deeper than storm wave base)
• Depth of water (Bottom): Outer shelf (deeper than storm wave base)
• Lithofacies (Top): Conglomerate, Sandstone
• Lithofacies (Top, Minor): Siltstone, Sandy mudstone
• Lithofacies (Upper): Mudstone-dominant interbedded sandstone and mudstone, Sandy mudstone, Siltstone
• Lithofacies (Upper, Minor): Sandstone
• Lithofacies (Middle): Sandstone-dominant interbedded sandstone and mudstone, Sandstone
• Lithofacies (Middle, Minor): Sandy mudstone
• Lithofacies (Lower): Mudstone-dominant interbedded sandstone and mudstone, Siltstone
• Lithofacies (Lower, Minor): Sandstone
• Lithofacies (Bottom): Conglomerate, Sandstone
• Sedimentary structures (Top): Parallel stratification
• Sedimentary structures (Upper): Hummocky cross-stratification
• Sedimentary structures (Middle): Parallel stratification, Reversed graded bedding

• Thickness: 750 - 770 m
• Thickness (Top): 15 - 40 m
• Thickness (Upper): 330 - 340 m
• Thickness (Middle): 40 - 95 m
• Thickness (Lower): 250 - 295 m
• Thickness (Bottom): 45 m or thicker
• Upper limit: Conformity (Nishinakayama Formation)
• Lower limit: Unconformity (Sangun Metamorphic Rocks, Toyohigashi Group)

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

• Distribution: Ochi, Shimonoseki city, Yamaguchi pref.; Kamiono - Ipponmatsu - Okaeda - Tabe pass, Kikukawa village, Shimonoseki city, Yamaguchi pref.; Kamiozuki, Ozuki village, Shimonoseki city, Yamaguchi pref.; Mount Ongasa - Mount Shirayama, Shimonoseki city, Yamaguchi pref.
• Fossils (Ammonoids): Arietites sp., Amaltheus sp., Vermiceras cf. spiratissimum
• Fossils: Bivalves (Nuculana sp., Modiolus sp., Cardinia sp., Oxytoma sp.), Gastropods, Plants, Corals (Chomatoceris cyclolitoides)
• Fossils (Trace fossils): Phycosiphon isp.

• Maeda and Oyama (2019) Jour. Geol. Soc. Japan, vol.125, no.8, pp.585-594 DOI
• Kawamura (2010) Jour. Geol. Soc. Japan, vol.116, no.1, pp.27-44 DOI