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Tsukabara Formation

• Type locality: Tsukabara, Haramachi ward, Minamisoma city, Fukushima prefecture
• Coherent formation
• Valley-fill deposit
• Pleistocene (Last interglacial period)

• Sedimentary facies: Marine
• Climate: Cooler than present
• Lithofacies (Upper): Clay, Silt
• Lithofacies (Lower): Gravels, Sands

• Thickness: ca.7 - 10 m
• Upper limit: Conformity (Middle I Terrace Deposit (Haramachi), Middle I Terrace Deposit (Namie))
• Lower limit: Unconformity (Dainenji Formation)

• Distribution: Tsukabara, Haramachi ward, Minamisoma city, Fukushima pref.; Urajiri, Odaka ward, Minamisoma city, Fukushima pref.; Ozawa, Futaba city, Futaba county, Fukushima pref.
• Fossils: Fishes (Perciformies, Tetraodontiformes), Trace fossils
• Fossils (Shellfishes): Anomia chinensis, Arca boucardi, Batillaria multiformis, Capulus yokoyamai, Crassostrea gigas, Cryptomya busoensis, Cyclina orientalis, Dosinia (Dosinella) penicillata, Indomitrella lischkei, Macoma tokyoensis, Meretrix lusoria, Mya japonica, Mitrella bicincta, Rapana venosa, Reticunassa festiva, Saxidomus purpuratus, Scapharca subcrenata, Tapes philippinarum, Trapezium japonicum
• Fossils (Plants): Acer sieboldianum, Alnus japonica, Berchemia racemosa, Betula grossa, Carpinus tschonoskii, Cornus controversa, Corylus heterophylla var. thunbergii, Euonymus alatus, Fagus crenata, Fraxinus cf. japonica, Hydrangea paniculata, Ilex cf. geniculata, Ilex cf. nipponica, Kalopanax pictus, Lindera umbellata, Phellodendron amurense, Pinus (Diploxylon) sp., Quercus serrata, Rhamnus sp., Rhododendron kaempferi, Rosa sp., Scirpus sp., Smilax china, Styrax japonicus, Styrax obassia, Tilia maximowicziana, Trapa incisa, Trapa macropoda, Viburnum wrightii, Wisteria sp.
• Tephra: Hu-TG

• Kubo et al. (2015) Geology of the Kawamata District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, AIST, 86p. (in Japanese with English abstract 4p.)
• Kubo et al. (1994) Geology of the Namie and Iwaki-Tomioka District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 104p. (in Japanese with English abstract 7p.)
• Kubo et al. (1990) Geology of the Haramachi and Omika District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 138p. (in Japanese with English abstract 7p.)