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Shirataki Unit Aoya and Yokoyama, 2009

Invalid synonym: Besshi unit, Besshi nappe

• High P/T metamorphic rocks
• Deposition: Late Cretaceous
• Cooling: Late Cretaceous (89 - 76 Ma, K-Ar, Ar-Ar)

• Metamorphic facies: Pumpellyite-Actinolite, Greenschist, Epidote-Amphibolite
• Metamorphic facies (Upper): Garnet zone, Albite-biotite zone, Oligoclase-biotite zone
• Metamorphic facies (Middle): Chlorite zone
• Metamorphic facies (Middle, Minor): Mafic schist, Psammitic schist, Siliceous schsit
• Metamorphic facies (Lower): Chlorite zone
• Lithofacies (Upper): Mafic schist
• Lithofacies (Middle): Pelitic schist
• Lithofacies (Lower): Mafic schist, Mélange of pelitic schist, siliceous schist and mafic schist

• Thickness (Upper): ca. 500 m
• Thickness (Lower): ca. 100 - 200 m
• Upper limit: Thrust fault
• Lower limit: Thrust fault

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

• Distribution: Shirataki, Niihama city, Ehime pref.; Toyosaka, Shikokuchuo city, Ehime pref.; Umaji, Ikeda town, Miyoshi city, Tokushima pref.

• Noda et al. (2017) Geology of the Kan-onji District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, AIST, 96p. (in Japanese with English abstract 4p.)
• Aoya et al. (2017) Jour. Geol. Soc. Japan, vol.123, no.7, pp.491-514 DOI
• Aoya et al. (2013) Geology of the Niihama District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, AIST, 181p. (in Japanese with English abstract 3p.)