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Tawaraniwa Formation Ishii et al., 1982

• Type locality: Tawaraniwa - Kusata, Ishinomaki city, Miyagi prefecture
• Coherent formation
• Pliocene
• Correlation: Dainenji Formation

• Sedimentary facies (Upper): Terrestrial
• Sedimentary facies (Lower): Marine
• Lithofacies (Upper): Interbedded sandy siltstone and sandstone
• Lithofacies (Upper, Minor): Lignite
• Lithofacies (Lower): Sandstone
• Lithofacies (Minor): Conglomerate
• Sedimentary structures: Pipe rocks, Bioturbation

• Thickness: 50 m
• Thickness (Upper): ca. 30 m
• Thickness (Lower): ca. 20 m
• Upper limit: Unconformity (Terrace deposit)
• Lower limit: Conformity (Omotezawa Formation), Unconformity (Asahiyama Andesite Member, Kakeyama Conglomerate Member)

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

• Distribution: Tawaraniwa - Kusata, Ishinomaki city, Miyagi pref.
• Fossils: Brachiopods (Lingula unguis)
• Fossils (Shellfishes): Crassostrea sp., Laevicardium sp., Macoma tokyoensis, Mya japonica
• Fossils (Diatoms): Actinocyclus ehrenbergii, Actinocyclus ingens, Actinoptychus splendens, Actinoptychus undulatus, Amphora sp., Anaulus sp., Aulacosira granulata, Auliscus spp., Bacillaria paradoxa, Biddulphia aurita, Cocconeis scutellum, Coscinodiscus marginatus, Coscinodiscus temperi, Cyclotella kützingiana Cyclotella striata, Cymbella spp., Denticula kamtschatica, Denticulopsis kamtschatica, Diploneis smithii, Epithemia spp., Eunotia sp., Grammatophora sp., Melosira sol, Melosira sulcata, Navicula sp., Nitzschia punctata, Opephora martyi, Pinnularia sp., Plagiogramma staurophorum, Rhaphoneis sp., Rhizosolenia styliformis, Rhopaloida sp., Stephanopyxis spp., Thalassionema nitzschioides, Thalassiosira antiqua, Thalassiothrix longissima

• Takizawa et al. (1984) Geology of the Ishinomaki District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 103p. (in Japanese with English abstract 7p.)
• 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.)