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Asahidake West Upper Lava and Pyroclastic Rock

Abbr. WU

• Type locality: 1,640 m above sea level, Piukenai river, Mount Taisetsu, Hokkaido
• Volcanic rocks
• Pleistocene

• Sedimentary facies: Pyroclastic fall deposit
• Lithofacies: Welded pyroclastic rocks, Pyroclastic breccia, Volcanic breccia, Tuff breccia, Scoria (volcanic block, lapilli), Pumice (volcanic block, lapilli)
• Lithofacies: +/- Olivine-bearing clinopyroxene-orthopyroxene andesite, Orthopyroxene-clinopyroxene dacite
• Sedimentary structures: Graded bedding

• Source: Summit of Mount Asahidake
• Eruptive volume: 0.6 km³ DRE
• Thickness (WU-1): 70 m
• Upper limit: Unconformity
• Lower limit: Unconformity

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

• Distribution: North - West foot, Mount Asahidake, Mount Taisetsu, Hokkaido

• Ishige and Nakagawa (2017) Jour. Geol. Soc. Japan, vol.123, no.2, pp.73-91, DOI