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Bangamoriyama Formation (Kitamura, 1979) Ishii et al., 1982

Invalid synonym: Nakasuzu Formation

• Type locality: Mount Bangamori, Rifu city - Osato city, Miyagi county, Miyagi prefecture
• Coherent formation
• late Miocene
• Correlation: Tsunaki Formation

• Lithofacies: Pumiceous sandstone
• Lithofacies (Minor): Siltstone
• Lithofacies (Basal): Conglomerate
• Sedimentary structures: Wedge-shaped cross-stratification, Trough cross-stratification, Planar cross-stratification

• Thickness: 30 - 180 m or thicker
• Upper limit: Transitional (Aoso Formation), Conformity (Omatsuzawa Formation), Unconformity (Embana Formation)
• Lower limit (Hataya Formation, Kashimadai hill): The boundary between massive medium sandstone and overlying pumice-bearing breccia coarse sandstone
• Lower limit (Hataya Formation, Matsushima hill): Bottom of relatively well-sorted quartz-rich sandstone
• Lower limit: Unconformity (Irisugaya Formation, Kashimadai Formation, Hataya Formation)

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

• Distribution: Mount Bangamori, Rifu city - Osato city, Miyagi county, Miyagi pref.; Irisugaya - Miyanomae - Sawaoto, Rifu city, Miyagi county, Miyagi pref.; Itaya - Kurouchizawa, Osato city, Kurokawa county, Miyagi pref.
• Fossils: Whales (Ribs, Vertebra), Bivalves (Chlamys miyatokoensis)
• Fossils (Diatoms): Actinocyclus ellipticus, Actinocyclus ingens, Actinoptychus undulatus, Amphora spp., Aulacosira granulata, Cocconeis costata, Coscinodiscus symbolophorus, Delphineis surirella, Denticulopsis hustedtii, Diploneis spp., Eunotia sp., Goniothecium rogersii, Grammatophora sp., Melosira sulcata, Plagiogramma staurophorum, Pseudopodosira aff. hyalina, Rhaphoneis miocenica, Thalassionema nitzschioides

• Kitamura et al. (1986) Geology of the Sendai District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 134p. (in Japanese with English abstract 9p.)
• Kitamura et al. (1983) Geology of the Yoshioka District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 50p. (in Japanese with English abstract 5p.)
• Ishii et al. (1982) Geology of the Matsushima District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 121p. (in Japanese with English abstract 9p.)