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Minawa Unit

Synonym: Minawa Formation, Minoda Formation, Kamo Formation

• High P/T metamorphic rocks
• Protolith (Lower): Northern Shimanto Belt
• Deposition (Upper): Precambrian (1,820 Ma, ICP)
• Deposition (Lower): Late Cretaceous (93 - 81 Ma, U-Pb)
• Metamorphism (Upper): Early Cretaceous (120 - 110 Ma, 74 - 72 Ma, K-Ar)
• Metamorphism (Lower): Late Cretaceous - Paleocene (65 Ma, K-Ar)
• Correlation (Upper): Asemigawa Unit
• Correlation: Shirataki Mafic Schist

• Metamorphic facies: Chlorite
• Metamorphic facies: Blueschist facies, Epidote blueschist subfacies
• Sedimentary facies: Oceanic crust formed at Mid Ocean Ridge, Chert, Trench fill deposit
• Lithofacies: Pelitic schist, Psammitic schsit, Greenschsit, Siliceous schist
• Lithofacies (Minor): Serpentinite

• Upper limit: Thrust fault
• Lower limit: Oboke Fault

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

• Distribution: Oboke valley - Iyagawa river - Umaji - Umaji - Satokawa river - Mount Tsunatsukiyama - Mount Gonomaruyama - Mount Tenjinyama - Kurohaze - Kakisako - Iuchi, Miyoshi city, Tokushima pref.; Keda, Higashimiyoshi city, Miyoshi county, Tokushima pref.

• Noda et al. (2021) Geology of the Ikeda District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, AIST, 150p. (in Japanese with English abstract 5p.)
• Otoh et al. (2010) Jour. Geol. Soc. Japan, vol.119, No.2, pp.333-346 DOI
• Okamoto et al. (2009) Jour. Geol. Soc. Japan, vol.115, Supplement, pp.37-49 DOI
• Aoki et al. (2007) Jour. Geol. Soc. Japan, vol.113, no.5, pp.171-183 DOI