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Nobeyamahara Formation

• Type locality (Upper): west of Shinanokawakami station, Kawakami city, Minamisaku county, Nagano prefecture
• Coherent formation
• Pleistocene
• Lower: Pleistocene (278,000, 274,000 yBP, FT)
• Correlation (Lower): Ashidaira Pyroclastic Rocks, Honzawa Lava and Scoria, Uminokuchi Pyroclastic Rocks
• Interfingered (Lower): Takaishigawa Formation

• Sedimentary facies (Middle): Dammed lake formed by pyroclastic flow deposit
• Lithofacies (Upper): Volcanic gravels, Volcanic sands, Volcanic breccia
• Lithofacies (Upper, Minor): Scoria, Lava, Pumice Volcanic ash, Peat
• Lithofacies (Middle): Mud, Peat, Sands, Gravels
• Lithofacies (Middle, Minor): Scoria, Pumice, Volcanic breccia, Loam
• Lithofacies (Lower): Scoria, Tuff breccia, Volcanic breccia, Loam, Mudflow deposit, Gravels
• Lithofacies (Lower, Minor): Pumice, Sands, Mud, Peat
• Sedimentary structures (Middle): Parallel stratification, Cross stratification

• Thickness (Upper): 80 m
• Thickness (Middle): 40 m
• Thickness (Middle, Peat): 2 - 16 m
• Thickness (Lower): 75 m or thicker
• Upper limit: Unconformity (Uminokuchibokujo Lava)
• Lower limit: Unconformity (Takaishigawa Lava, Honzawa Lava and Scoria)

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

• Distribution: Nobeyamahara, Minamimaki city, Minamisaku county, Nagano pref.; west of Shinanokawakami station, Kawakami city, Minamisaku county, Nagano pref.; Itabashi river - Somasoe river, Minamimaki city, Minamisaku county, Nagano pref.
• Fossils (Middle, Peat): Diatoms, Mosses, Abies sp., Chamaecyparis obtusa, Larix leptolepis, Magnolia abovata, Picea bicolor, Picea maximoviczii, Rhododendron sp., Tsuga diversiflolia
• Fossils (Middle, Pollen): Abies sp., Picea sp., Tsuga sp., Ulmus sp., Zelkova sp.

• Kawachi (1977) Geology of the Yatsugatake District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 92p. (in Japanese with English abstract 4p.)
• Kawachi (1974) Geology of the Tateshinayama District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 114p. (in Japanese with English abstract 5p.)