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Yuguruma Formation Imaizumi and Kotaka, 1952

• Type locality: Yuguruma - Nakayashiki - Yokobuchi, Takanosu, Kitaakita city, Akita prefecture
• Old Takanosu lake fill deposit
• Coherent formation
• Pleistocene

• Sedimentary facies: Lacustrine
• Sedimentary facies: Marsh
• Lithofacies: Conglomerate, Sandy mud, Sands, Silt, Clay
• Lithofacies (Minor): Lignite, Pumiceous volcanic ash
• Sedimentary structures: Cross stratification

• Thickness: 10 - 40 m
• Lower limit: Unconformity (Osarubegawa FormationMaeyamagawa Formation)

• Distribution: Yuguruma - Nakayashiki - Yokobuchi, Takanosu, Kitaakita city, Akita pref.; Bozawa - Tduzureko, Kitaakita city, Akita pref.
• Fossils: Brasenia schreberi, Equisetum sp., Menyanthes trifoliata, Phragmites sp., Picea bicolor, Pseudolarix kaempferi, Scirpes? sp., Sequoia sp., Styrax japonicum, Trapa manshurica, Trapa maximowiczii, Tsuga sp.

• Sumi and Moritani (1973) Geology of the Yonaizawa District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 46p. (in Japanese with English abstract 4p.)
• Hirayama and Sumi (1963) Takanosu, Explanatory Text of the Geological Map of Japan, Scale 1:50,000, Geological Survey of Japan, 90p. (in Japanese with English abstract 7p.)