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Honzawa Lava and Scoria

• Volcanic rocks
• Pleistocene
• Correlation: Lower Nobeyamahara Formation

• Lithofacies: Olivine augite basalt scoria, Scoriaceous agglomerate, Volcanic breccia, Lava
• Lithofacies (Minor): Scoriaceous pyroclastic flow deposit, Mudflow deposit, Sands, Gravels, Pumice

• Thickness: 100 m
• Upper limit: Unconformity (Tomyodaira Pyroclastic Rocks, Itokaya Pyroclastic Flow Deposit, Nobeyamahara Formation)
• Lower limit: Unconformity (Totarunosawa Lava, Hikage Formation, Takaishigawa Formation)

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

• Distribution: Yukawa river - Inago - Takaishi river - Somazoe river, Komi city, Minamisaku county, Nagano pref.; Honzawa hot spring - Shiranagi creek, Minamimaki city, Minamisaku county, Nagano pref.

• Kawachi (1977) Geology of the Yatsugatake District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 92p. (in Japanese with English abstract 4p.)
• Kawachi (1974) Geology of the Tateshinayama District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 114p. (in Japanese with English abstract 5p.)