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Kobitawatashi Sandstone and Shale Member

• Coherent formation
• Early Cretaceous, Berriasian (Ammonoids)
• Correlation: Kogoshio Formation

• Lithofacies (Kb4): Interbedded sandstone and shale
• Lithofacies (Kb3): Siltstone
• Lithofacies (Kb3, Minor): Sandstone, Shale
• Lithofacies (Kb2): Interbedded sandstone and shale
• Lithofacies (Kb1): Conglomerate, Sandstone
• Sedimentary structures (Kb2): Graded bedding, Trace fossils

• Thickness: ca. 400 m
• Upper limit: Transitional (Futawatashi Shale Member), Unconformity (Lower Andesitic Volcaniclastics Member)

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

• Distribution: Aji island - Tashiro island, Ishinomaki city, Miyagi pref.
• Fossils (Ammonoids): Berriasella sp., Kilianella sp., Thurmanniceras cf. isokusensis
• Fossils (Shellfishes): Amphidonte cf. kumaensis, Astarte higoensis, Astarte cf. spiliensis, Ctenosireon cf. probossideum, Grammatodon sp., Mantellum akiyamae, Myophorella (Haldata) crenulata, Myophorella (Promyophorella) orientalis, Niethea sp., Opis (Trigonopis) cf. torinosuensis, Parallerodon kesennumaensis, Pleotomya? sp., Somapecten cf. kamimamensis, Syncyclonema? sp., Torinosucatella cf. kobayashii

• Takizawa et al. (1987) Geology of the Yoriiso District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 74p. (in Japanese with English abstract 5p.)
• Takizawa et al. (1974) Geology of the Kinkasan District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 62p. (in Japanese with English abstract 5p.)