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Kominato Tuff Member Nakajima et al., 1981

Tuff dominant part of middle - lower Amatsu Formation

• Type locality: Kominato, Kamogawa city, Chiba prefecture
• Coherent formation
• Forearc basin sediments
• Miocene (ca. 11 - 9.5 Ma)

• Sedimentary facies: Marine
• Lithofacies (Upper): Sandy mudstone, Muddy sandstone
• Lithofacies (Middle): Siltstone
• Lithofacies (Lower): Sandy mudstone, Muddy sandstone
• Lithofacies (Minor): Basalt - Andesite scoriaceous tuff, Conglomerate
• Sedimentary structures: Cross stratificaiton
• Paleocurrent: South to North

• Thickness: 70 - 237 m
• Upper limit: Top of Am40
• Lower limit: Bottom of Am28

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

• Distribution: Kominato - Matsusaki river - Fukurokura river - Taenoura, Kamogawa city, Chiba pref.
• Tephra: Am28, Am40

• Sawada et al. (2009) Jour. Geol. Soc. Japan, vol.115, no.5, pp.206-222 DOI
• Nakajima and Watanabe (2005) Geology of the Futtsu District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, AIST, 102p. (in Japanese with English abstract 8p.)
• Nakajima et al. (1981) Geology of the Kamogawa District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 107p. (in Japanese with English abstract 7p.)