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Myogazawa Formation Sakai, 1986

• Type locality: Mount Hanzo, Utsunomiya city, Tochigi prefecture
• Volcanic rocks
• Miocene (15.3 Ma, K-Ar)

• Sedimentary facies: Marine
• Sedimentary facies: Lava dome, Shallow intrusion facies
• Lithofacies (Upper): Pyroxene andesite lava, Lapilli tuff
• Lithofacies (Middle): Hornblende dacite lava, Tuff, Lapilli tuff
• Lithofacies (Middle, Minor): Tuffaceous sandstone, Mudstone
• Lithofacies (Lower): Breccia, Conglomerate, Sandstone, Pyroxene andesite lava, Pyroclastic rocks
• Sedimentary structures (Middle): Trough cross-stratification, Parallel stratification, Planar cross-stratification
• Paleocurrent (Middle): North to South

• Thickness: ca. 50 - 190 m or thicker
• Upper limit: Abut unconformity (Oya Formation)
• Lower limit: Unconformity (Tochigi Complex)

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

• Distribution: Oya village - Mount Hanzo - Myogazawa - Akagawa dam - Kuriyasawa dam, Utsunomiya city, Tochigi pref.; Mount Moroyama, Kanuma city, Tochigi pref.; Nakainokura, Nikko city, Tochigi pref.
• Fossils (Shellfishes): Chlamys? sp.

• Matsui et al. (2011) Jour. Geol. Soc. Japan, vol.117, Supplement, pp.89-102 DOI
• Yoshikawa et al. (2010) Geology of the Utsunomiya District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, AIST, 79p. (in Japanese with English abstract 6p.)