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Yachiho-kogen Lavas

• Type locality: 1,600 m above sea level, Oishi river, Sakuho city, Minamisaku county, Nagano prefecture
• Volcanic rocks
• early Pleistocene (1.06 Ma, K-Ar)

• Lithofacies: Basalt
• Lithofacies: Lavas (more than 10 flow units), Welded pyroclastic rocks, Agglutinates, Dykes

• Source: Mount Kengamine
• Eruptive volume: 13.3 km³
• Thickness (A unit): 1 - 5 m
• Upper limit: Kengamine Pyroclastics
• Lower limit: Oishigawa-futamata Lavas

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

• Distribution: 1,620 - 1,950 m above sea level, Mount Kengamine - Oishi river, Sakuho city, Minamisaku county, Nagano pref.

• Nishiki and Takahashi (2012) Jour. Geol. Soc. Japan, vol.118, no.8, pp.499-515 DOI
• Nishiki et al. (2007) Jour. Geol. Soc. Japan, vol.113, no.5, pp.193-211 DOI