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Donzurubo Formation Morimoto et al., 1953

• Type locality: Anamushitoge pass - Harakawa river - Asukagawa river, Kashiba city, Nara prefecture
• Volcanic rocks
• Miocene (16, 15.4 Ma, K-Ar)

• Sedimentary facies (Upper): Pyroclastic flow deposits, Pyroclastic surge deposits
• Sedimentary facies (Middle, Minor): Reworked deposits
• Lithofacies (Upper): Garnet biotite rhyolite Lava, Lapilli tuff, Tuff breccia, Tuff
• Lithofacies (Middle): Garnet biotite andesite lava, Pyroclastic rocks, Garnet-bearing hornblende orthopyroxene andesite
• Lithofacies (Lower): Garnet biotite rhyolite lapilli tuff
• Structures (Upper): Bomb sag structure
• Structures (Middle): Columnar joints, Parallel stratification, Graded bedding, Reversed graded bedding

• Thickness: 750 m or thicker
• Thickness (Lower): ca. 20 - 150 m or thicker
• Upper limit: Conformity (Harakawa Formation)
• Lower limit: Unconformity

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

• Distribution: Anamushitoge pass - Mount Donzurubo - Tajirotoge pass, Kashiba city, Nara pref.; Asukagawa river, Asuka city, Takaichi county, Nara pref.; Mount Nijosan, Katsuragi city, Nara pref. - Taishi city, Minamikawachi county, Osaka pref.; Botando - Iwayatoge pass - Rokutanji temple, Taishi city, Minamikawachi county, Osaka pref.; Harakawa river, Kashiwara city, Osaka pref.

• Sato et al. (2012) Jour. Geol. Soc. Japan, vol.118, Supplement, pp.53-69 DOI
• Shinjoe et al. (2007) Jour. Geol. Soc. Japan, vol.113, no.7, pp.310-325 DOI
• Miyachi et al. (1998) Geology of the Osaka-Tonambu District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 113p. (in Japanese with English abstract 5p.)