Karaumedate Formation

[ Top ] [ Japanese ]

Karaumedate Formation (Tachibana, 1952) Okami, 1973

Type locality: Mount Karaumedate, Higashiyama village, Ichinoseki city, Iwate prefecture
Coherent formation
early Carboniferous, ? - Visean (Brachiopods)

Sedimentary facies: Marine
Lithofacies (Top): Limestone
Lithofacies (Upper): Tuff, Tuffaceous sandy mudstone, Calcareous sandstone
Lithofacies (Lower): Interbedded sandstone and mudstone, Mudstone
Lithofacies (Lower, Minor): Conglomerate
Lithofacies (Bottom): Conglomerate, Sandstone

Thickness: ca. 500 m
Upper limit: Conformity (Takezawa Formation)
Lower limit: Lithofacies boundary (Bottom of sandstone and/or interbedded sandstone and mudstone)

South Kitakami Belt (Ichinoseki, Iwate pref.)
[ Upper ]
?--?--?--?--?-
Nozuchi Formation
~~~~~~~~~~~~~~
Takezawa Formation
--------------
Karaumedate Formation
--------------
Tobigamori Formation
~~~~~~~~~~~~~~
[ Lower ]

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

Distribution: Mount Karaumedate, Higashiyama village, Ichinoseki city, Iwate pref.; Natsuyama, Tagotsu, Higashiyama village, Ichinoseki city, Iwate pref.; Kita-Iwairi - Minami-Iwairi, Nagasaka, Higashiyama village, Ichinoseki city, Miyagi pref.
Fossils: Trilobites (Phyllipsia sp.), Bivalves (Aviculopecten sp.), Crinoids, Plants
Fossils (Brachiopods): Kitakamithyris sp., Martinia sp., Spirifer nagasakaensis, Spirifer verneuili, Syringothyris sp.

Ehiro and Morikiyo (2013) Jour. Geol. Soc. Japan, vol.119, Supplement, pp.47-67 DOI
Takeuchi and Mikoshiba (2002) Geology of the Senmaya District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, AIST, 76p. (in Japanese with English abstract 3p.)