Kumi Rhyolite

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Kumi Rhyolite

Volcanic rocks
late Miocene

Lithofacies: Rhyolite lava (4 flow units)
Sedimentary structures: Banded structure
Sedimentary structures (Minor): Spherulitic structure

Thickness (2nd flow unit): ca. 150 m or thinner

Kumi Rhyolite
[ Upper ]
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Dairyo Trachyte
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[ Lower ]

Middle part (Northwest)
[ Upper ]
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Kumi Rhyolite
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[ Lower ]

Omosu Formation
[ Upper ]
~~~~~~~~~~~~~~
Upper part
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Middle part
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Lower part
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[ Lower ]

Oki-Dogo island, Shimane pref.
[ Upper ]
~~~~~~~~~~~~~~
Omosu Formation
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Tsuma Formation
~~~~~~~~~~~~~~
[ Lower ]

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

Distribution: Igo - Kumi - Dai - Yamada - Mount Soramineyama, Okinoshima city, Oki county, Shimane pref.
Tephra: Pyroclastic Rock 4, Pyroclastic Rock 5, Pyroclastic Rock 6

Yamauchi et al. (2009) Geology of the Saigo District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, AIST, 118p. (in Japanese with English abstract 3p.)