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Towada-Hachinohe Pyroclastic Flow Deposit (Nakagawa et al., 1972) Takarada and Muraoka, 2004

Abbr.: To-H

Synonym (Invalid): Hachinohe Pumice Flow Tuff, Hachinohe ignimbrite, Fukuoka Pumice (a part), Fukuoka Formation (a part)

• Type locality: Hodo creek, Kowatari, Gonohe city, Sannohe county, Aomori prefecture
• Tephra
• Pleistocene (14 - 12 ka BP, ¹⁴C, 15.3 - 14.9 ka, ¹⁴O), Winter season
• Correlation: Towada Pumice Flow Deposit?

• Lithofacies: Un-welded dacitic - rhyolitic pyroclastic flow deposit (2 - 3 flow units)
• Lithofacies (Pumice): Hornblende-bearing
• Lithofacies (Upper Unit): A few flow units
• Lithofacies (Lower Unit): A few flow units
• Sedimentary structures: Reversed graded bedding

• Thickness: 0 - 20 m
• Thickness (Upper Unit): Several m
• Thickness (Lower Unit): Several - several tens m
• Source: Towada caldera
• Upper limit: Unconformity (Towada-Chuseri Pyroclastic Fall Deposit, Towada Terrace Deposits)
• Lower limit: Unconformity (Towada Okuse Pyroclastic Flow Deposit, Towada-Ofudo Pyroclastic Flow Deposit, Hakkoda 1st-stage Pyroclastic Flow Deposit, Hakkoda 2nd-stage Pyroclastic Flow Deposit, Fujisawamori Lava, Koganetai Lava, Tsuta Debris Avalanche Deposit, Tashirotai Lacustrine Formation, Iodake Lava, Odake Lava, Shichinohe Terrace Deposits)

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

• Distribution: Aomori pref. - Iwate pref., Honshu island, Japan
• Distribution: Kowatari, Gonohe city, Sannohe county, Aomori pref.; Kiriake, Hirakawa city, Aomori pref.; Mount Yamato, Hiranai city, Higashitsugaru county, Aomori pref.Namioka river, Namioka, Aomori city, Aomori pref.; Nakayashiki - Ashizawa - Odamichi - Hanzai pond - Hirayama - Sadoro river, Towada city, Aomori pref.; Araya, Shichinohe city, Kamikita county, Aomori pref.

• Okuno (2019) Jour. Geol. Soc. Japan, vol.125, no.1, pp.41-53 DOI
• Nagamori et al. (2013) Geology of the Aomori-Seibu District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, AIST, 67p. (in Japanese with English abstract 4p.)
• Kudo (2005) Geology of the Towada District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, AIST, 79p. (in Japanese with English abstract 3p.)
• Takarada and Muraoka (2004) Geology of the Hakkoda San District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, AIST, 86p. (in Japanese with English abstract 4p.)
• Muraoka and Hase (1990) Geology of the Kuroishi District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 124p. (in Japanese with English abstract 8p.)
• Uemura (1983) Geology of the Asamushi District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 40p. (in Japanese with English abstract 4p.)