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Shirakurayama Lavas Shimazu et al., 1983

• Type locality: Mount Shirakura, Sakae city, Shimominochi county, Nagano prefecture
• Volcanic rocks
• Pleistocene (0.77 Ma, K-Ar)

• Lithofacies: Calc-alkaline
• Lithofacies: Quartz-bearing hypersthene augite dacitic andesite lava
• Lithofacies (Minor): Tuff breccia, Volcanic breccia

• Thickness: 250 m
• Upper limit: Unconformity (Torikabuto Summit Lava)
• Lower limit: Unconformity (Oneyama Lavas, Takizawa Lavas, Takayamazawa-Onizawa Pyroclastic Flow Deposit, Ketto Formation, Akiyamago Formation)

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

• Distribution: Mount Shirakura - Onizawa creek - summit of Mount Akakura, Sakae city, Shimominochi county, Nagano pref.

• Igarashi et al. (2007) Jour. Geol. Soc. Japan, vol.113, no.11, pp.565-584 DOI
• Shimazu and Tateishi (1993) Geology of the Naebasan District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 90p. (in Japanese with English abstract 5p.)