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Haibara Formation Saito, 1961

• Type locality: Higashiharaichiba, Shinko town, Nagano city, Nagano prefecture
• Coherent formation
• early Pleistocene

• Lithofacies (Upper): Sands, Silt
• Lithofacies (Upper, Minor): Welded tuff
• Lithofacies (Middle): Gravels, Sands, Silt
• Lithofacies (Middle, Minor): Pumice tuff, Tuff
• Lithofacies (Middle): Gravels
• Lithofacies (Middle, Minor): Pumice tuff, Tuff

• Thickness: 150 - 200 m
• Thickness (Welded tuff): 10 - 20 m
• Upper limit: Unconformity (Ooka Mudflow Deposit, Omachi Tephra)
• Lower limit: Unconformity (Hijiriyama Andesite, Akada Formation, Shinoyama Volcanics, Kumeji Pyroclastic Member)

• Distribution: Higashiharaichiba - Tanoguchi - Haibara - Takano - Karuizawa, Shinko town, Nagano city, Nagano pref.

• Kato and Akahane (1986) Geology of the Nagano District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 120p. (in Japanese with English abstract 5p.)