[ Top ] [ Japanese ]

Kogura Formation Kubo et al., 1993

• Type locality: Kogura, Higashiagatsuma city, Agatsuma county, Gunma prefecture
• Volcanic rocks
• Pliocene (3.05 Ma, K-Ar)

• Lithofacies: Orthopyroxene clinopyroxene andesite lava, Volcanic breccia

• Thickness: 300 m or thicker
• Upper limit: Unconformity (Older Haruna Volcanic Fan Deposits)
• Lower limit: Unconformity (Agatsuma Formation)

• Distribution: Mount Kogara - Oto - Kogura, Higashiagatsuma city, Agatsuma county, Gunma pref.

• Geshi and Takeuchi (2012) Geology of the Haruna San District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, AIST, 79p. (in Japanese with English abstract 3p.)