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Okata volcano

Invalid synonym: Okata Basalts

• Volcanic rocks
• Stratovolcano
• Pleistocene (< 0.42 Ma, K-Ar)
• Intruded by: Basalt dykes

• Sedimentary facies: Terrestrial
• Lithofacies: Low-alkaline tholeiite series
• Lithofacies: Augite olivine basalt, Olivine basalt lava (10 - 20 flow units), Tuff breccia
• Lithofacies (Minor): Olivine pyroxene andesite lava, Spatter, Scoria

• Source: in the vicinity of Okata
• Thickness (A unit): 1 - 2 m
• Upper limit: Unconformity (Older edifice)

• Distribution: western part of north coast of Izu-Oshima island
• Distribution: Cape Chibasaki - Nutahama seashore - Goishihama seashore - Cape Kazahayasaki - Cape Koguchimisaki - Okata port, Oshima city, Tokyo

• Isshiki (1984) Geology of the Oshima District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 133p. (in Japanese with English abstract 5p.)