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Okushimayama Welded Tuff Ishida et al., 1984

• Volcanic rocks
• Cretaceous (60.7, 57.8 Ma, K-Ar)
• Intruded by: Chomeiji Body, Miyagahama Body

• Sedimentary facies: Pyroclastic flow deposit
• Lithofacies: Biotite hornblende rhyolite welded tuff
• Sedimentary structures: Joints

• Lower limit: Unconformity (Miyagahama Welded Tuff, Kamewariyama Welded Tuff)

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

• Distribution: Mount Okushimayama - Mount Chomeijiyama - Miyagahama - Onohama - Odagahama - Mount Kakuyokuzan, Omihachiman city, Shiga pref.

• Yoshida et al. (2003) Geology of the Omi-Hachiman District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, AIST, 72p. (in Japanese with English abstract 3p.)
• Ishida et al. (1984) Geology of the Hikone-Seibu District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 121p. (in Japanese with English abstract 6p.)