Tochio Formation

Tochio Formation (Maeda, 1958) Kawai, 1961

Invalid synonym: Tochio Alternation

Type locality: Kashiate valley, Tochio, Okuhidaonsengo, Takayama city, Gifu prefecture
Coherent formation
Jurassic - Cretaceous
Contemporaneous heterotopic facies: Sugizaki Formation
Correlation: Akaiwa Subgroup

Sedimentary facies: Freshwater, Brackish
Lithofacies: Arkose sandstone
Lithofacies (Minor): Mudstone, Conglomerate, Breccia

Thickness: ca. 150 - 600 m
Upper limit: Unconformity (Yarimi Tuff Member)
Lower limit: Unconformity? (Granitoids)

Tetori Group (Hidafurukawa, Gifu pref.)
[ Upper ]
~~~~~~~~~~~~~~
Inagoe Formaiton
--------------
Taie Formation
--------------
Sugizaki Formation / Tochio Formation
--------------
Numamachi Formation
--------------
Tanemura Formation
~~~~~~~~~~~~~~
[ Lower ]

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

Distribution: Kashiate valley - Tochio - Horadani valley - Kansaka - Kamata - Koitodani valley - Murakami - Sodegatani valley - Konabedani valley - Hotakadaira, Okuhidaonsengo, Takayama city, Gifu pref.
Fossils (Plants): Cladophlebis denticulata, Cladophlebis exiliformis, Onychiopsis elongata, Podozamites lanceolatus, Xenoxylon latiporosum
Fossils (Kamitakara fauna): Crenotrapezium kobayashii, Exogyrinae gen. et sp. indet, Melanoides sp., Polymesoda (Isodomella) kobayashii, Polymesoda (Paracorbicula) sanchuensis, Tetoria (Tetoria) yokoyamai, Viviparus sp.

Matsukawa et al. (2007) Jour. Geol. Soc. Japan, vol.113, no.8, pp.417-437 DOI
Harayama (1990) Geology of the Kamikochi District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 175p. (in Japanese with English abstract 11p.)