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Yatsuoyama Pyroclastics

• Type locality: Mount Yatsuoyama, Taga city, Inukami county, Shiga prefecture
• Volcanic rocks
• Cretaceous (ca. 76 Ma, Rb-Sr; ca. 67 Ma, K-Ar; ca. 62 Ma, FT)
• Intruded by: Inugami Granite Porphyry

• Lithofacies (Upper): Pumice tuff
• Lithofacies (Lower): Interbedded welded tuff and tuff
• Sedimentary structures (Lower): Cross stratification

• Thickness: ca. 320 m
• Thickness (Upper): 220 m
• Thickness (Lower): 30 - 90 m
• Distribution (East - West): 4 km
• Distribution (South - North): 5 km
• Lower limit: Unconformity (Hatasho Quartz Porphyry, Kaiwara Welded Tuff)

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

• Distribution: Mount Yatsuoyama - Shakubutsu - Narasaki - Kozukura, Taga city, Inukami county, Shiga pref.; Usogawa dam, Higashiomi city, Shiga pref.

• Harayama et al. (1989) Geology of the Gozaishoyama District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 145p. (in Japanese with English abstract 6p.)
• 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.)
• Miyamura et al. (1976) Geology of the Hikonetobu District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 49p. (in Japanese with English abstract 6p.)