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Hotaka Andesites Harayama, 1975

Synonym: Yari-Hotaka Caldera volcanic fills

• Type locality: Kamikochi, Matsumoto city, Nagano prefecture
• Volcanic rocks
• early Pleistocene
• Correlation: Nyukawa Pyroclastic Flow Deposit, Hotaka-Kd39 Tephra, Jiigatake Andesite
• Intruded by: Takidani Granodiorite

• Lithofacies: Dacitic welded tuff
• Lithofacies (Minor): Rhyolitic tuff, Andesite lava, Tuff breccia, Diorite porphyry, Caldera-collapse breccia

• Thickness (Top): 300 m or thicker
• Thickness (Upper): 1,500 m
• Thickness (Lower): 500 m
• Distribution (Width): 4 - 5 km
• Upper limit: Unconformity (Nakanoyu Pyroclastic Rocks)
• Lower limit: Unconformity (Yarigatake Metamorphic Rocks, Byobunoatama Granophyre, Okumarusawa Granite, Paleogene granite)

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

• Distribution: Mount Yarigatake, Matsumoto city - Omachi city, Nagano pref. - Takayama city, Gifu pref.; Azumino city, Nagano pref.

• Harayama (2015) Jour. Geol. Soc. Japan, vol.121, no.10, pp.373-389, DOI
• Harayama et al. (1991) Geology of the Yarigatake District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 190p. (in Japanese with English abstract 8p.)
• Harayama (1990) Geology of the Kamikochi District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 175p. (in Japanese with English abstract 11p.)