[ Top ] [ Japanese ]

Wadaira Tuff Member (Matsuda and Mizuno, 1955) Ozaki and Sugiyama, 2018

Invalid synonym: Kumazawa Formation

• Type locality: Wadaira, Isshiki, Minobu city, Minamikoma county, Yamanashi prefecture
• Volcanic rocks
• middle Miocene

• Sedimentary facies: Marine
• Sedimentary facies: Felsic submarine volcano products
• Sedimentary facies: Submarine pyroclastic flow deposit
• Depth of water: Abbyssal (shallower than CCD)
• Lithofacies: Dacite tuff, Lapilli tuff
• Lithofacies (Minor): Tuff breccia, Lava, Tuffaceous sandstone, Mudstone, Mudstone-dominant interbedded sandstone and mudstone
• Sedimentary structures: Double graded bedding, Sole marks
• Paleocurrent: Northeast - Southwest to Norhtwest - Southeast

• Source: northeast of Ashikawa, Yamanashi pref.
• Thickness: ca. 100 - 700 m
• Upper limit: Conformity (Kamiisshiki Volcanic Breccia Member, Tsukimibashi Volcaniclastic Member)
• Lower limit: Interfingered (Kanzaka Mudstone Member)

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

• Distribution: Isshiki - Teuchizawa - Kamogaritsumugi - Kumazawa - Toida - Kurumada - Misawa - Kamitanbara - Shimotanbara - Tokiwa - Kirifusagi - Michi - Kubo - Yunooku, Minobu city, Minamikoma county, Yamanashi pref.; Miyahara - Tsuzurasawa - Iwashita - Gohachi - Teradoko, Ichikawamisato city, Nishiyatsushiro county, Yamanashi pref.

• Ozaki and Sugiyama (2018) Geology of the Minobu District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, AIST, 169p. (in Japanese with English abstract 7p.)