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Yokodake Volcanic Rocks

• Volcanic rocks
• Pleistocene

• Lithofacies (Upper): Olivine hypersthene augite andesite lava
• Lithofacies (Middle): Scoria
• Lithofacies (Middle, Minor): Lava (3 flow units), Agglomerate
• Lithofacies (Lower): Olivine hypersthene augite andesite lava (more than 20 flow units), Agglomerate, Scoriaceous agglomerate, Volcanic breccia
• Lithofacies (Lower, Minor): Welded tuff, Scoria

• Thickness (Upper): 20 m
• Thickness (Middle): 80 m
• Thickness (Middle, Scoria): 60 m or thicker
• Thickness (Middle, A unit): 2 - 15 m
• Thickness (Lower): 200 m or thicker
• Thickness (Lower, A unit): 0.5 - 15 m
• Distribution (Upper, Width): 800 m
• Running distance (Upper): ca. 1.25 km
• Running distance (Lower): 5 km

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

• Distribution: Mount Yokodake, Chino city - Minamimaki city, Minamisaku county, Nagano pref.

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