Nishimata Unit

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Nishimata Unit Endo and Yokoyama, 2019

Invalid synonyum: Miyanoue Formation

Type locality: Nishimata, Kami city, Kochi prefecture
Accretionary complex
Deposition (Chert): early Permian, Triassic (ca. 280 Ma, Radiolarians, Conodonts)
Deposition (Mudstone): Early - Middle Jurassic (Radiolarians)
Accretion: Middle Jurassic
Deposition: Jurassic
Correlation: Sumaizuku Unit

Sedimentary facies: Marine
Sedimentary facies: Mid-ocean ridge basalt
Metamorphic facies: Prehnite-Pumpellyite facies
Metamorphic facies: 230 - 250 degree C, ca. 0.35 GPa
Lithofacies: Mélange facies
Matrix: Mudstone
Exotic blocks (Crusts, Slabs): Sandstone, Chert, Basalt, Dolerite

Upper limit: Thrust fault (Akatsukayama Unit)
Lower limit: Thrust fault (Kamiananai Unit)

Northern Chichibu Belt (Motoyama, Kochi pref.)
[ Upper ]
/--/--/--/--/-
Akatsukayama Unit
/--/--/--/--/-
Nishimata Unit
/--/--/--/--/-
Kamiananai Unit
/--/--/--/--/-
Akaragi Unit
/--/--/--/--/-
[ Lower ]

Chichibu Belt
[ Upper ]
/--/--/--/--/-
Kurosegawa Belt
/--/--/--/--/-
Northern Chichibu Belt
/--/--/--/--/-
Southern Chichibu Belt
/--/--/--/--/-
[ Lower ]

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

Distribution: Nishimata, Kami city, Kochi pref.
Fossils: ConodontsFossils (Radiolarians): Laxtorum? jurassicu, Parahsuum sp., Pseudoalbaillella sp., Tricolocapsa plicarum

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.)