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Okuyama Debris Avalanche Deposits Ozawa et al., 1988

Invalid synonym: Okuyama Pyroclastic Flow Deposit

• Stratovolcano
• Coherent formation
• Pleistocene
• Older than Higher IV Terrace Deposit, and younger than Higher V Terrace Deposit.

• Lithofacies (Blocks): Andesite lava

• Thickness: 10 - 50 m
• Lower limit: Unconformity (Yurihara Debris Deposits, Higher IV Terrace Deposit)

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

• Distribution: Okuyama - Uguisu river, Chokai town, Yurihonjo city, Akita pref.; Koyoshi river Sarukura - Sainokami, Yurihonjo city, Akita pref.

• Nakano and Tsuchiya (1992) Geology of the Chokaisan and Fukura District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 138p. (in Japanese with English abstract 7p.)
• Ozawa et al. (1988) Geology of the Yashima District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 87p. (in Japanese with English abstract 5p.)