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Maekawahontani Pyroclastic Flow Deposit

• Tephra
• middle Pleistocene

• Sedimentary facies (Lower, Minor): Debris flow deposit
• Lithofacies (Upper): Olivine-bearing hypersthene augite andesite pyroclastic flow deposit
• Lithofacies (Lower): Sands, Gravels
• Sedimentary structures (Lower): Parallel stratification

• Thickness (Upper): 2 m or thicker
• Thickness (Lower): ca. 3 - 15 m
• Upper limit: Unconformity (Kuraigahara Lava)
• Lower limit: Unconformity (Maekawa Lava)

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

• Distribution: 1,700 m above sea level and 2,250 - 2,350 m above sea level, Maekawahontani valley, Azumi, Matsumoto city, Nagano pref.

• Nakano et al. (1995) Geology of the Norikuradake District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 139p. (in Japanese with English abstract 4p.)