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Yokota Formation Tokuhashi and Endo, 1984

• Type locality: Otorii, Sodegaura city ,Chiba prefecture
• Coherent formation
• Paleo-Tokyo bay fill deposit
• Pleistocene (MIS 7.1)

• Sedimentary facies: Marine
• Sedimentary facies: River mouth of tidal river
• Lithofacies (Upper): Mud, Peat
• Lithofacies (Lower): Muddy sands
• Lithofacies (Basal, Minor): Gravel-bearing sands
• Sedimentary structures: Trough-Herringbone cross-stratification
• Sedimentary structures (Upper): Pipe rocks

• Thickness: 3 - 6 m or thicker
• Thickness (Upper): 4 m or thicker
• Thickness (Lower): 2 - 3 m
• Upper limit: Unconformity (Kioroshi Formation, Joso Formation)
• Lower limit: Conformity (Kiyokawa Formation)

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

• Distribution: Otorii, Sodegaura city, Chiba pref.; Anegasaki - Hikida, Ichihara city, Chiba pref.; Sugao, Kisarazu city, Chiba pref., Aso, Namegata city, Ibaraki pref.; Kamihataki, Hokota city, Ibaraki pref.
• Fossils: Plant roots, Leaves, Plant fragments
• Tephra: As (Aso Tephra), Yk1, Yk2, Yk3

• Sakata et al. (2018) Jour. Geol. Soc. Japan, vol.124, no.5, pp.331-346 DOI
• Ooi et al. (2013) Jour. Geol. Soc. Japan, vol.119, no.7, pp.488-505 DOI
• Ooi and Yokoyama (2011) Jour. Geol. Soc. Japan, vol.117, Supplement, pp.103-120 DOI
• Komatsubara et al. (2004) Geology of the Kisarazu District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, AIST, 64p. (in Japanese with English abstract 3p.)
• Tokuhashi and Endo (1984) Geology of the Anesaki District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 136p. (in Japanese with English abstract 6p.)