Kamiananai Unit

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Kamiananai Unit Endo and Yokoyama, 2019

Ivalid synonym: Shimoyakawa Formation

Type locality: Ananaigawa dam, Kami city, Kochi prefecture
Accretionary complex
Deposition (Chert): Permian, Triassic (Conodonts, Radiolarians)
Deposition (Mudstone): Jurassic (Radiolarians)
Accretion: Middle Jurassic
Metamorphism: Cretaceous (171 - 123 Ma, Ar-Ar)
Correlation: Kamiyoshida Unit, Nakaoi Unit

Sedimentary facies: Marine
Sedimentary facies: Intra-plate volcanic activity
Metamorphic facies: 270 - 290 degree C, ca. 0.45 - 0.6 GPa
Lithofacies (Upper): Reworked hyaloclastite
Lithofacies (Upper): Basalt tuff, Lapilli tuff, Tuff breccia, Volcanic conglomerate, Volcanic breccia
Lithofacies: Chert, Sandstone, Breccia
Lithofacies (Lower): Alkaline basalt
Sedimentary structures: Slump structures

Upper limit: Thrust fault (Nishimata Unit)
Lower limit: Thrust fault (Akaragi 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: Ananaigawa dam, Kami city, Kochi pref.
Fossils: Conodonts
Fossils (Radilarians): Follicucullus monacanthus, Hsuum sp., Pseudoalbaillella cf. fusiformis, Pseudoalbaillella aff. globosa, Tricolocapsa sp.

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.)