Miyatoko Tuff Member

Miyatoko Tuff Member Nakamura, 1941 ex Kitamura et al., 1981

Invalid synonym: Miyatoko Tuff, Ogigakura Tuff Member

Type locality: Miyatoko, Taiwa city, Kurokawa county, Miyagi prefecture
Volcanic rocks
Pleistocene
Contemporaneous heterotopic facies: middle Onoda Formation
Intruded by: Nanatsumori Lava

Sedimentary facies: Caldera volcano
Lithofacies: Dacite - andesite pyroclastic flow deposit
Lithofacies: Pumice tuff
Lithofacies (Minor): Sandy tuff, Lapilli tuff, Tuff breccia, Tuffaceous siltstone

Thickness: 30 - 250 m
Upper limit: Conformity (Wakahata Formation, Onoda Formation), Unconformity (Higashihara Formation, Arakawa Pyroclastic Rocks, Akakuzureyama Lava)
Lower limit: Conformity (Sanbongi Formation), Unconformity (Nanakita Formation, Aoso Formation, Otsutsumi Formation, Tatsunokuchi Formation)

Nanatsumori volcano
[ Upper ]
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Ohatayama Pyroclastic Rocks
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Akakuzureyama Lava / Ohatayama Lavas / Kamikadajin Lava
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Nanatsumori Lava
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Wakahata Formation
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Miyatoko Tuff Member
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[ Lower ]

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

Distribution: Miyatoko - Yoshioka, Taiwa city, Kurokawa county, Miyagi pref.; Arigafukuro, Sanbongi, Osaki city, Miyagi pref.; Koguriyama - Ojojihara, Shikama city, Kami county, Miyagi pref.; Ohira, Ohira city, Kurokawa county, Miyagi pref.

Miyamoto et al. (2013) Jour. Geol. Soc. Japan, vol.119, Supplement, pp.27-46 DOI
Kitamura et al. (1983) Geology of the Yoshioka District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 50p. (in Japanese with English abstract 5p.)
Kitamura et al. (1981) Geology of the Furukawa District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 32p. (in Japanese with English abstract 4p.)