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Haruna-Futatsudake-Shibukawa Fall Tephra Geshi and Takeuchi, 2012

• Type locality: Kurosawa river, Ono, Shibukawa city, Gunma prefecture
• Type locality: Takizawa river, Uenohara, Yoshioka city, Kitagunma county, Gunma prefecture
• Tephra
• Holocene (end of 5th century; 489 cal AD, Wiggle matching)

• Sedimentary facies: Pyroclastic fall deposit, Pyroclastic surge
• Lithofacies: Volcanic ash
• Lithofacies (Minor): Accretionry lapilli

• Source: Haruna volcano
• Mode of eruption: Phreatomagmatic
• Thickness: ca. 40 cm - 1.2 m
• Volume: ca. 0.3 km³

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

• Distribution: Kurosawa river, Ono, Shibukawa city, Gunma pref.; Takizawa river, Uenohara, Yoshioka city, Kitagunma county, Gunma pref.; Nakano, 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.)