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Shimohorizawa Lava Harayama, 1990

• Type locality: Shimohorizawa creek, Azumi, Matsumoto city, Nagano prefecture
• Volcanic rocks
• Holocene (4.0 ka)

• Lithofacies: Augite hypersthene biotite hornblende andesite lava (more than 2 flow units)
• Sedimentary structures: Autobrecciated structure

• Upper limit: Unconformity (Yakedake Dome Lava, Nakahorizawa Debris Flow Deposit, Hosoike Dome Lava, Nakao Pyroclastic Flow Deposit)
• Lower limit: Unconformity (Hosoike Dome Lava, Kurotanigento Lava, Nakanoyu Pyroclastic Rocks, Warudaniyama Lava)

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

• Distribution: Shimohorizawa creek - west of Mount Yakedake - Nakahorizawa creek - Nakanoyu hotspring, Azumi, Matsumoto city, Nagano pref.

• Oikawa et al. (2010) Jour. Geol. Soc. Japan, vol.116, Supplement, pp.49-61 DOI
• Harayama (1990) Geology of the Kamikochi District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 175p. (in Japanese with English abstract 11p.)