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Takada Rhyolites

The name was defined as Takada although the locality name is Takata.

Invalid synonym: Sanno Formation

• Type locality: Takata county, Hiroshima prefecture
• Volcanic rocks
• Late Cretaceous (95 - 85 Ma; 77.5 Ma, K-Ar)
• Correlation: Ochi Group, Abu Group, Hikimi Group, Shinzojiyama Rhyolites, Oyorogiyama Group, Aioi Group, Shirakiyama Rhyolites
• Intruded by: Shikijiki Granite, Mitsumori Granite, Asuna Granite, Kure Granite, Ojizo Granite, Miyazakari Granite, Nigata Granodiorite, Northern Kure Dike Swarms, Ishiuchi-Konigata Dike Swarms

• Lithofacies: Biotite rhyolite welded tuff, Hornblende biotite dacite - Rhyolite welded tuff, Rhyolite vitreous crystalline tuff, Rhyolite vitreous tuff
• Lithofacies (Minor): Tuffaceous conglomerate, Tuffaceous sandstone, Mudstone, Lapilli tuff
• Sedimentary structures (Minor): Parallel stratification

• Thickness: 750 - 2,000 m or thicker
• Lower limit: Conformity, partly Unconformity (Kisa Andesites), Unconformity (Hasumi Formation, Kuga Group)

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

• Distribution: Takata county, Hiroshima pref.; Yamane - Midori - Takamiya, Akitakata city, Hiroshima pref.; Kumami - Funo - Sakugi, Miyoshi city, Hiroshima pref.; Mihara city, Hiroshima pref.; Fukuyama city, Hiroshima pref.; Akitsu town, Higashihitoshima city, Hiroshima pref.; Mount Onigajoyama - Mount Takahachiyama - Harayama - Mount Hokotoriyama - Mount Mizugamaruyama - Mount Odayama - Mount Kokuzoyama - Mount Gosasozan - Mount Shiroyama - Mount Tenguboyama, Hiroshima city, Hiroshima pref.; Mount Futatsuyama - Kabusakashita, Higashihiroshima city, Hiroshima pref.; Togochi - Uegahata, Onan city, Och county, Shimane pref.

• Takagi and Mizuno (1999) Geology of the Kaitaichi District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 49p. (in Japanese with English abstract 4p.)
• Matsuura (1990) Geology of the Akana District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 73p. (in Japanese with English abstract 5p.)
• Higashimoto et al. (1985) Geology of the Kure District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 93p. (in Japanese with English abstract 6p.)