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Maeko Member

Formerly included in Uonuma Group.

• Type locality: Yokotaira? river - Kusso, Tsunan city, Nakauonuma county, Niigata prefecture
• Volcanic rocks
• Pleistocene (1.32 Ma, K-Ar)
• Correlation: middle Uonuma Group

• Lithofacies: Lapilli tuff
• Lithofacies (Minor): Tuff breccia, Andesite lava

• Thickness: 200 m or thicker
• Upper limit: Unconformity (Kusso Formation)
• Lower limit: Top of the andesite-dominant tuff breccia bed
• Lower limit: Conformity (Niteno Member, Higashinosawa Formation)

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

• Distribution: Yokotaira? river - Kusso, Tsunan city, Nakauonuma county, Niigata pref.; Shikumi river - Kamagawa river - Kitano river, Sakae city, Shimominochi county, Nagano pref.
• Tephra: SK030

• Shimazu and Tateishi (1993) Geology of the Naebasan District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 90p. (in Japanese with English abstract 5p.)