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Haruna-Futatsudake-Ikaho Pyroclastic Flow Deposit Geshi and Takeuchi, 2012

• Type locality: Owanzawa river - Numao river, Ubajima, Shibukawa city, Gunma prefecture
• Tephra
• Holocene (late 6th century - early 7th century; 555 - 615 AD, ¹⁴C)

• Sedimentary facies: Pyroclastic flow deposit, Pyroclastic surge deposit
• Lithofacies: Hornblende andesite pumice flow deposit
• Lithofacies (Minor): Charcoal
• Lithofacies (Pyroclastic surge): Volcanic sands, Lapilli

• Source: Haruna volcano
• Thickness: ca. 1 - 50 m or thicker
• Thickness (Pyroclastic surge): ca. 1 m or thinner

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

• Distribution: Sogo park - Takizawa river - Ogura - Harunashirakawa river, Shibukawa city, Gunma pref.; Owanzawa river - Numao river, Ubajima, Shibukawa city, Gunma pref.; Shimoshiba, Misato town, Takasaki city, Gunma pref.

• Geshi and Takeuchi (2012) Geology of the Haruna San District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, AIST, 79p. (in Japanese with English abstract 3p.)