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Shirataki Unit Aoya and Yokoyama, 2009

Invalid synonym: Besshi unit, Besshi nappe

• High P/T metamorphic rocks
• Deposition: Late Cretaceous
• Metamorphism: Late Cretaceous (92.6 Ma, FT)
• Accretion: Late Cretaceous (ca. 95 - 90 Ma or later)
• Cooling: Late Cretaceous (91 - 76 Ma, K-Ar, Ar-Ar)
• Correlation (Middle): Doganai Unit
• Intruded by: Andesite - Dacite dikes, Porphyrytic granite dikes

• Metamorphic facies: Pumpellyite-Actinolite, Greenschist, Epidote-Amphibolite
• Metamorphic facies (Upper): Garnet zone (420 - 460 degree C, 0.7 - 0.85 GPa), Albite-biotite zone (490 - 550 degree C, 0.8 - 0.95 GPa), Oligoclase-biotite zone (580 - 630 degree C, 0.9 - 1.1 GPa)
• Metamorphic facies (Middle): Chlorite zone (300 - 360 degree C, 0.55 - 0.65 GPa)
• Metamorphic facies (Lower): Chlorite zone (300 - 360 degree C, 0.55 - 0.65 GPa)
• Sedimentary facies (Ultramafic rocks): Tectonic blocks originated from serpentinized mantle wedge
• Lithofacies (Upper): Mafic schist
• Lithofacies (Middle): Pelitic schist
• Metamorphic facies (Middle, Minor): Mafic schist, Psammitic schist, Siliceous schsit
• Lithofacies (Lower): Mafic schist, Mélange of pelitic schist, siliceous schist and mafic schist
• Lithofacies (Minor): Meta-gabbro, Ultramafic rocks

• Thickness (Upper): ca. 100 - 500 m
• Thickness (Middle): ca. 300 - 1,000 m
• Thickness (Lower): ca. 100 - 200 m
• Upper limit: Thrust fault (Kinouzu Unit)
• Lower limit: Thrust fault

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

• Distribution: Shichibangawa river, Niihama city, Ehime pref.; Toyosaka, Shikokuchuo city, Ehime pref.; Umaji, Ikeda town, Miyoshi city, Tokushima pref.; Shirataki - Mount Nojimine - Mount Kamojiroyama - Mount Mitsumoriyama - Komugiunedani - Mount Minaminoyama - Mount Notaniyama - Mount Inokawayama, Okawa city, Tosa county, Kochi pref.; Mount Kanpuzan - Mount Kanmuriyama - Heikedaira - Ashidanigawa river - Ichinotani - Mount Inamurayama - Mount Omoriyama, Ino city, Agawa county, Kochi pref.; Mount Iwatsutsujiyama, Tosa city, Tosa county, Kochi pref.; Shikinoiwa - Mount Jiyoshiyama - Kawaguchi, Otoyo city, Nagaoka county, Kochi pref.; Asemigawa river - Sakamoto - Gocha, Motoyama city, Nagaoka county, Kochi pref.

• Endo and Yokoyama (2019) Geology of the Motoyama District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, AIST, 100p. (in Japanese with English abstract 4p.)
• 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.)
• Aoya and Yokoyama (2009) Geology of the Hibihara District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, AIST, 75p. (in Japanese with English abstract 3p.)