Attari Formation

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Attari Formation (Onuki, 1969) Nishioka and Yoshikawa, 2004

Type locality: Sotoguchi - Attari, Akasaki town, Ofunato city, Iwate prefecture
Coherent formation
Contact metamorphism by Goyosan Pluton
Deposition: Early Cretaceous
Metamorphism: Early Cretaceous

Sedimentary facies: Marine (Shellfishes)
Lithofacies: Shale, Sandstone
Lithofacies (Minor): Andesite pyroclastic rocks, Felsic tuff, Conglomerate
Sedimentary structures: Parallel lamination, Convolute lamination, Gradded bedding, Hummocky cross-stratification

Thickness: ca. 320 m
Upper limit: Conformity (Ryori Formation)

Ofunato Group (Ryori, Iwate pref.)
[ Upper ]
?--?--?--?--?-
Takonoura Formation
--------------
Ryori Formation
--------------
Attari Formation
?--?--?--?--?-
[ Lower ]

Ofunato Group (Ofunato, Iwate pref.)
[ Upper ]
?--?--?--?--?-
Nagaiso Formation
--------------
Upper Hijochi Formation
--------------
Lower Hijochi Formation
--------------
Funagawara Formation
?--?--?--?--?-
[ Lower ]

Ofunato Subelt
[ Upper ]
?--?--?--?--?-
Massaki Group
~~~~~~~~~~~~~~
Ofunato Group
?--?--?--?--?-
[ Lower ]

South Kitakami Belt (after Permian)
[ West ]
::::::::::::::
Shizukawa-Hashiura Subbelt
::::::::::::::
Karakuwa-Oshika Subbelt
::::::::::::::
Ofunato Subelt
::::::::::::::
[ East ]

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

Distribution: Sotoguchi - Attari - Nagahama - Nochinoiri, Akasaki town, Ofunato city, Iwate pref.; Mount Imade - Tomioka, Ikawa town, Ofunato city, Iwate pref.

Nishioka and Yoshikawa (2004) Geology of the Ryori District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, AIST, 49p. (in Japanese with English abstract 3p.)