[ Top ] [ Japanese ]

Kibi Group

Invalid synonym: Yamajari Formation

• Type locality: Funazakatoge pass, Bizen city - Kamigori city, Okayama prefecture
• Coherent formation
• Eocene, Priabonian - Oligocene, Chattian (35.8 - 27.1 Ma, FT)
• Correlation: Maejima Formation, Namigata Formation, Kobe Group

• Sedimentary facies: Fluvial
• Sedimentary facies: Valley-fill deposit, Depth of valley is 150 m or deeper
• Lithofacies: Clast-supported conglomerate
• Lithofacies (Minor): Sandstone
• Sedimentary structures: Imbricate structures
• Paleocurrent: North to South

• Thickness: 5 - 100 m or thinner
• Upper limit: Unconformity (Yagane Formation, Ukan Formation, Nichioji Formation)
• Lower limit: Unconformity (Nariwa Group, Nibori Granite, Shashakiyama Formation, Hinase Formation, Ako Formation, Une Formation)

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

• Distribution: Nika, Kawakami town, Takahashi city, Okayama pref.; Hiwa-Okuguruma - Hata, Soja city, Okayama pref.; Kashiwagi - Takebe, Kibichuo city, Okayama pref.; Onakayama - Kinugasa, Wake city, Wake county, Okayama pref.; Mushiage, Oku town, Setouchi city, Okayama pref.; Waidanigawa river, Yoshinaga town, Bizen city, Okayama pref.; Funazakatoge pass, Bizen city - Kamigori city, Okayama pref.; Hase, Nishiune, Ako city, Okayama pref.

• Sato et al. (2022) Geology of the Wake District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, AIST, 106p. (in Japanese with English abstract 4p.)
• Sato et al. (2016) Geology of the Banshu-Ako District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, AIST, 68p. (in Japanese with English abstract 3p.)
• Yokota et al. (2009) Jour. Geol. Soc. Japan, vol.115, Supplement, pp.109-122 DOI
• Suzuki et al. (2009) Jour. Geol. Soc. Japan, vol.115, Supplement, pp.139-151 DOI