Omoiji Unit

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Omoiji Unit Wakita et al., 2007

High P/T metamorphic rocks
Protolith: Northern Chichibu Belt
Deposition: Late Cretaceous
Metamorphism: Late Cretaceous (109 - 97 Ma, Ar-Ar)
Intruded by: Rhyolite - Dacite dikes
Correlation: Akaragi Unit, Nagoro Unit

Metamorphic facies: Chlorite zone (300 - 360 degree C, 0.55 - 0.65 GPa)
Metamorphic facies: Pumpellyite-Actinolite (300 - 360�x, 0.55 - 0.65 GPa)
Lithofacies: Meta-chert, Pelitic phillite, Meta-sandstone, Meta-basalt tuff, Lava
Lithofacies (Minor): Crystalline limestone

Thickness: 1,500 m or thicker
Upper limit: Thrust fault (Kunimiyama Unit)

Sanbagawa Metamorphic Rocks (Hibihara, Kochi pref.)
[ Upper ]
/--/--/--/--/-
Omoiji Unit
/--/--/--/--/-
Kawamata Unit
/--/--/--/--/-
Shirataki Unit
/--/--/--/--/-
Nakashichiban Unit
/--/--/--/--/-
[ Lower ]

Sanbagawa Metamorphic Rocks (Ino, Kochi pref.)
[ Upper ]
/--/--/--/--/-
Omoiji Unit
/--/--/--/--/-
Kawamata Unit
/--/--/--/--/-
Dogauchi Unit
/--/--/--/--/-
[ Lower ]

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

Distribution: Uchino - Omoiji - Takaiwa - Kiyota - Kawamata, Ino city, Agawa county, Kochi pref.; Kamiyoshihara, Kochi city, Kochi pref.
Fossils (Radiolarians): Archaeodictyomitra sp., Hsuum sp.

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.)
Wakita et al. (2007) Geology of the Ino District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, AIST, 140p. (in Japanese with English abstract 4p.)