Yoneyama Chert Formation

[ Top ] [ Japanese ]

Yoneyama Chert Formation

Accretionary complex
Accretion: Jurassic
Correlation: Kosendoyama Chert Formation

Sedimentary facies: Marine
Lithofacies: Chert
Lithofacies (Minor): Mélange facies
Matrix (Minor): Mudstone

Thickness: ca. 70 - 200 m
Upper limit: Conformity (Sorayama Mudstone Formation)
Lower limit: Conformity (Rokuroshi Mudstone Formation)

Kuga Group (southeastern Iwakuni, Yamaguchi pref.)
[ Upper ]
/--/--/--/--/-
Sorayama Mudstone Formation
--------------
Yoneyama Chert Formation
--------------
Rokuroshi Mudstone Formation
--------------
Odomari Chert Formation
/--/--/--/--/-
Zenitsuboyama Formation
/--/--/--/--/-
[ Lower ]

Tamba Belt (East Yamaguchi pref.)
[ Upper ]
/--/--/--/--/-
Mikawa Group
/--/--/--/--/-
Kuga Group
/--/--/--/--/-
[ Lower ]

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

Distribution: Motoro - Hata - Hiuchiiwa - Yoneyama - Mount Daioyama - Datoko - Mineyama - Lake Gosenoko - Kohata, Iwakuni city, Yamaguchi pref.; Mount Himurodake, Yanai city, Yamaguchi pref.

Higashimoto et al. (1983) Geology of the Iwakuni District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 79p. (in Japanese with English abstract 6p.)