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Nakao Pyroclastic Flow Deposit Fujii et al., 1974

Invalid synonym: Kamihori Pyroclastic Flow Deposit

• Type locality: Ashiaraidani valley, Nakao, Okuhidaonsengo, Takayama city, Gifu prefecture
• Tephra
• Holocene (2.3 ka cal BP; 3,780, 2,850 yBP, ¹⁴C)
• Correlation: Yakedake Dome Lava

• Sedimentary facies: Block-and-ash-flow deposit of lava dome collapse type (Some flow units)
• Lithofacies: Augite biotite-bearing hypersthene hornblende andesite - dacite
• Sedimentary structures: Reversed graded bedding

• Source: Yakedake volcano - dome
• Thickness: ca. 30 m
• Lower limit: Unconformity (Hida Gaien Belt, Takidani Granodiorite, Kurotani Lava, Nakao Debris Flow Deposit, Nakahorizawa Debris Flow Deposit, Warudaniyama Lava, Shiramizudani Pyroclastic Rocks, Shimohorizawa lava, Nakaotoge Lava), Abut unconformity (Yakedake Dome Lava)

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

• Distribution: Shiramizudani valley - Ashiaraidani valley - Togesawa creek - Kamihorizawa creek - Nakahorizawa creek - Kurotani valley, Nakao, Okuhidaonsengo, Takayama city, Gifu 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.)