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Toyokawa Formation Nakajima et al., 2008

Invalid synonym: Kozakai Mud Formation, Kozakai Basal Gravel Formation, Kozakai Mud

• Type locality: underground of Yawata town, Toyokawa city, Aichi prefecture
• Coherent formation
• Pleistocene (MIS 5e)
• Contemporaneous heterotopic facies: Fukue Formation?

• Sedimentary facies (Upper): Marine, Brackish
• Sedimentary facies (Lower): Fluvial
• Sedimentary facies (Upper): Inner bay, Mudflat
• Sedimentary facies (Lower): River channel deposit, Flood plain
• Lithofacies (Upper): Mud
• Lithofacies (Middle): Sands
• Lithofacies (Lower): Sands, Gravels

• Thickness: 12 m
• Thickness: ca. 3 - 7 m
• Thickness: ca. 2 - 5 m
• Thickness: ca. 5 - 8 m
• Upper limit: Unconformity (Kozakai Formation)
• Lower limit: Unconformity (Atsumi Group)

• Distribution: Yawata town - Kozakai town - Toyotsu town, Toyokawa city, Aichi pref.
• Fossils: Fishes, Insects, Crabs, Echinoids, Banacles, Foraminifera, Bryozoans
• Fossils (Shellfishes): Alvenius ojianus, Cerithideopsilla djadjariensis, Clithon sowerbianus, Crassostrea gigas, Cylichnatys angusta, Fluviocingula elegantula, Macoma incongrua, Patelloida pygmaea lampanicola, Ringicula doliaris, Tegillarca granosa, Trapezium liratum, Trisidos kiyonoi
• Fossils (Plants): Abies firma, Pinus parviflora
• Fossils (Pollen): Fagus sp., Pinus sp., Quercus sp., Sciadopitys sp.

• Nakashima et al. (2008) Geology of the Toyohashi and Tahara District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, AIST, 113p. (in Japanese with English abstract 3p.)
• Miyazaki et al. (2008) Geology of the Goyu District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, AIST, 97p. (in Japanese with English abstract 3p.)