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Ajiro volcano Oikawa and Ishizuka, 2011

Invalid synonym: Ajiro Basalt

• Type locality: Ajiro - Suijingawa river, Atami city, Shizuoka prefecture
• Volcanic rocks
• Pleistocene (0.7 - 0.4 Ma, K-Ar)
• Intruded by: Dykes

• Sedimentary facies: Terrestrial
• Lithofacies: Tholeiite
• Lithofacies: Olivine basalt, Olivine clinopyroxene basalt - basaltic andesite
• Lithofacies (Minor): Aphyric basaltic andesite, Orthopyroxene clinopyroxene andesite
• Lithofacies (Upper): Bsalt - Basaltic andesite aa lava (more than 7 flow units)
• Lithofacies (Middle): Scoria
• Lithofacies (Lower): Scoriaceous - Spatter pyroclastic breccia, Tuff breccia, Lapilli tuff
• Lithofacies (Lower, Minor): Basalt - Andesite aa lava

• Source: southeast of Ajiro
• Thickness (Lava, A unit): several - 10 m
• Upper limit: Unconformity (Chojyagahara maar)
• Lower limit: Unconformity (Shimotaga volcano, Osaki volcano, Usami volcano)

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

• Distribution: Ajiro - Suijingawa river, Atami city, Shizuoka pref.; Kameishi pass - Chojagahara, Izunokuni city, Shizuoka pref.

• Oikawa and Ishizuka (2011) Geology of the Atami District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, AIST, 61p. (in Japanese with English abstract 3p.)