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Futawatashi Shale Member

• Type locality: Futawatashi, Aji island, Ishinomaki city, Miyagi prefecture
• Coherent formation
• Cretaceous
• Correlation: Koyamada Formation

• Lithofacies (Upper): Shale, Silty shale, Sandstone
• Lithofacies (Main): Shale
• Lithofacies (Main, Minor): Siltstone, Sandstone
• Lithofacies (Lower): Sandy shale, Interbedded shale and sandstone, Shale
• Sedimentary structures (Upper): Cross stratification, Slump structure
• Sedimentary structures (Main): Cross stratification, Sole marks, Slump structure
• Sedimentary structures (Lower): Trace fossils
• Paleocurrent: South to North

• Thickness: ca. 200 - 620 m
• Upper limit: Unconformity (Lower Andesitic Volcaniclastics Member)
• Lower limit: Transitional (Kobitawatashi Sandstone and Shale Member)

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

• Distribution: Futawatashi, Aji island - Ayukawahama - Niiyamahama - Tashiro island, Ishinomaki city, Miyagi pref.
• Fossils: Brachiopods
• Fossils (Ammonoids): Kilianella sp., Lyticoceras sp., Sarasinella aff. hyattii
• Fossils (Shellfishes): Amphidonte cf. kumaensis, Myophorella (Promyophorella) orientalis

• 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.)