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Okawachi Formation Yamamoto et al., 2002

• Type locality: Yumesakigawa river, Kumabe Yumesaki town, Himeji city, Hyogo prefecture
• Volcanic rocks
• Large scale caldera-fill deposit
• Late Cretaceous
• Intruded by: Teramae Body, Tsurui Body

• Sedimentary facies: Dacite - Rhyolite pyroclastic flow deposits
• Sedimentary facies (Minor): Debris avalanche deposits
• Lithofacies: Welded lapilli tuff, Tuff breccia
• Lithofacies (Minor): Rhyolite lava, Dacite Lava
• Lithofacies (Minor): Breccia, Tuffaceous sandstone, Mudstone, Dacite tuff

• Thickness: ca. 200 - 700 m
• Thickness (A unit): 10 - 40 m
• Upper limit: Unconformity (Nagusayama Formation, Mineyama Formation, Ikuno Formation, Kasagatayama Formation)
• Lower limit: Unconformity (Yamasaki Formation, Wakai Complex, Yachikusa Complex)

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

• Distribution: Kumabe Yumesaki town, Himeji city, Hyogo pref.; Teramae, Okawachi - Fukumoto - Ochi - Yoshitomi - Inozasa - Iwaya, Kamikawa city, Kanzaki county, Hyogo pref.; Mount Kasagatayama, Taka city, Taka county, Hyogo pref.; Obata, Ichikawa city, Kanzaki county, Hyogo pref.

• Yoshikawa et al. (2005) Geology of the Ikuno District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, AIST, 48p. (in Japanese with English abstract 3p.)
• Yamamoto et al. (2002) Geology of the Yamasaki District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, AIST, 48p. (in Japanese with English abstract 4p.)