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Nomuragawa Formation Kobayashi et al., 2004

• Type locality: Oga peninsula, Akita prefecture
• Coherent formation
• early Miocene (22 - 19 Ma, K-Ar, FT)
• Correlation: Daijima Formation

• Lithofacies: Tholeiite basalt, Basaltic andesite, Dacite
• Lithofacies (Basalt): Lavas, Pyroclastic rocks
• Lithofacies (Basaltic andesite): Lavas, Pyroclastic rocks, Fall deposit, Surge deposit
• Lithofacies (Dacite): Lapilli tuff, Pyroclastic flow deposit
• Lithofacies (Bottom): Conglomerate, Sandstone, Siltstone

• Thickness: 500 m
• Source (Dacite): Tateyamamisaki caldera, Honzan volcanic vent
• Upper limit: Unconformity (Nishikurosawa Formation)
• Lower limit: Abut unconformity (Shinzan Rhyolite Member), Unconformity (Kamo Lava Member)

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

• Distribution: Nomura river - northern flank of Mount Shinzan, Oga city, Akita pref.

• Kano (2018) Jour. Geol. Soc. Japan, vol.124, no.10, pp.781-803 DOI
• Kano et al. (2012) Jour. Geol. Soc. Japan, vol.118, no.6, pp.351-364 DOI
• Kobayashi et al. (2010) Jour. Geol. Soc. Japan, vol.116, no.10, pp.552-562 DOI
• Sato et al. (2009) Jour. Geol. Soc. Japan, vol.115, no.1, pp.31-46 DOI