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Shashakiyama Formation Sato et al., 2022

• Type locality: Mount Shinjoyama - Mount Shashakiyama, Okayama city, Okayama prefecture
• Volcanic rocks
• Late Cretaceous (ca. 95.2 Ma, FT)
• Intruded by: Momoezuki Quartz Diorite

• Sedimentary facies: Terrestrial
• Sedimentary facies (Minor): Lacustrine
• Lithofacies (Top): Biotite hornblende rhyolite welded tuff
• Lithofacies (Upper): Dacite - Rhyolite lapilli tuff, Tuff
• Lithofacies (Middle): Hornblende-bearing biotite rhyolite welded tuff, Lapilli tuff
• Lithofacies (Lower): Rhyolite tuff, Mudstone
• Lithofacies (Bottom): Biotite rhyolite tuff, Lapilli tuff

• Thickness: 700 m or thicker
• Thickness (Top): 120 m or thicker
• Thickness (Upper): ca. 150 m
• Thickness (Middle): 200 m or thicker
• Thickness (Lower): Several - 30 m
• Thickness (Bottom): ca. 200 m
• Distribution (East - West): 5.6 km
• Distribution (South - North): 5.2 km
• Upper limit: Unconformity (Takasagoyama Formation, Kibi Group)
• Lower limit: Unconformity (Ejiri Unit)

• Distribution: Mount Shinjoyama - Mount Shashakiyama - Mount Ohibatayama, Okayama city, Okayama pref.

• Sato et al. (2022) Geology of the Wake District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, AIST, 106p. (in Japanese with English abstract 4p.)