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Kota Formation Igarashi, 1967

• Type locality: Kotagahama seashore, Joetsu city, Niigata prefecture
• Coherent formation
• early Pleistocene

• Sedimentary facies (Upper): Freshwater
• Sedimentary facies (Lower): Marine
• Sedimentary facies (Lower): Sublittoral
• Depth of water (Lower): 50 - 200 m (Shell fossils)
• Lithofacies (Upper): Clay, Sands, Gravels
• Lithofacies (Upper, Minor): Lignite
• Lithofacies (Lower): Sands
• Lithofacies (Lower, Minor): Silt, Clay, Interbedded clay and sands, Fossils beds, Volcanic ash

• Thickness (Upper): ca. 130 m
• Thickness (Lower): ca. 70 m
• Upper limit: Unconformity (Ainokaze Formation, Hirayama Formation)
• Lower limit: Unconformity (Nodani Formation)

• Distribution: Kotagahama seashore - Shozenjigawa, Joetsu city, Niigata pref.
• Fossils: Foraminifera
• Fossils (Upper, Plants): Acer sp., Aesculus turbinata, Alnus cf. japonica, Corylus heterophylla, Cryptomeria japonica, Fagus crenata, Fagus aff. hayatae, Juglans mandshurica subsp. seiboldiana, Magnolia cf. kobus, Menyanthes trifoliata, Paliurus sp., Picea sp., Pterocarya rhoifolia,, Quercus (Lepidobalanus) sp., Sapindus mukurossi, Sapium sebiferum var. pleistoceaca, Scirpus sp., Styrax japonica, Styrax obossia, Tilia sp., Trapa macropoda, Vitis sp.
• Fossils (Lower, Shellfishes): Glossaulax hagenoshitensis, Mizuhopecten tokyoensis, Turritella saishuensis etigoensis
• Fossils (Pollen): Alnus sp., Cryptomeria sp., Fagus sp., Metasequoia sp., Pinus sp., Tsuga sp.

• Akahane and Kato (1989) Geology of the Takada-Seibu District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 89p. (in Japanese with English abstract 3p.)