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Wayama Tuff Member Shimazu and Tateishi, 1993

• Type locality: Nakatsu river, Wayama, Sakae city, Shimominochi county, Nagano prefecture
• Volcanic rocks
• Miocene

• Lithofacies: Dacite sandy tuff, Lapilli tuff, Tuff breccia
• Lithofacies (Minor): Dacite lava, Volcanic conglomerate, Tuffaceous shale

• Thickness: 100 m or thicker
• Upper limit: Unconformity (Maekura Lavas and Pyroclastics, Takayamazawa-Onizawa Pyroclastic Flow Deposit, Uenohara Welded Tuff)
• Lower limit: Interfingered (Yashiki Conglomerate Member)

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

• Distribution: Nakatsu river, Wayama - Koakasawa, Sakae city, Shimominochi county, Nagano pref.; Akiyama forest road, Sakae city, Shimominochi county, Nagano pref.
• Fossils: Wood fragments

• Shimazu and Tateishi (1993) Geology of the Naebasan District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 90p. (in Japanese with English abstract 5p.)