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Akaura Sandstone Member

Invalid synonym: Iori Formation

• Type locality: Akaura town, Nanao city, Ishikawa prefecture
• Coherent formation
• Miocene
• Interfingered: Taki Conglomerate Member, Takabatake Conglomerate Member
• Contemporaneous heterotopic facies: Taki Conglomerate Member

• Sedimentary facies: Marine
• Lithofacies (Top): Glauconite sandstone
• Lithofacies: Granitic sandstone
• Lithofacies (Minor): Mudstone, Andesitic conglomerate
• Sedimentary structures: Cross stratification

• Thickness: 0 - 250 m
• Thickness (Top): Several m
• Upper limit: Parallel unconformity (Mushizaki Mudstone Member), Conformity (Shibagaki Terrace Deposit)
• Lower limit: Conformity (Uwadana Mudstone Member), Conformity, partly Interfingered (Tane Alternation Member), Interfingered (Taki Conglomerate Member), Abut unconformity (Anamizu Formation)

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

• Distribution: Akaura town - Sakiyama peninsula, Nanao city, Ishikawa pref.; Amadan, Shiga city, Hakui county, Ishikawa pref.
• Fossils (Top): Desmostylus sp. (Molar), Shellfishes (Chlamys crassivenia), Brachiopods (Terebratulina quantoensis), Sponges (Aphrocallistes)
• Fossils (Shellfishes): Nemocardium sp.

• Imai et al. (1966) Geology of the Ochigata and Abugashima District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 67p. (in Japanese with English abstract 4p.)
• Imai (1965) Koguchiseto, Explanatory Text of the Geological Map of Japan, Scale 1:50,000, Geological Survey of Japan, 26p. (in Japanese with English abstract 4p.)