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Hiwasa Unit (Nakagawa, 1976), Hara et al., 2014

Invalid synonym: Hiwasa Formation, Gokenzan Formation, Todoroki Formation

• Type locality: Hiwasa, Minami city, Kaifu county, Tokushima prefecture
• Accretionary complex
• Deposition (Tuff): Late Cretaceous, Campanian (73.5 Ma, U-Pb)
• Deposition (Sandstone): Late Cretaceous, Maastrichtian (69.6, 67.8 Ma, U-Pb)
• Deposition (Mudstone): Late Cretaceous, Campanian - Maastrichtian (Radiolarians)
• Correlation: Oboke Unit, Nonokawa Formation

• Sedimentary facies: Marine
• Lithofacies: Coherent facies
• Lithofacies (Minor): Broken facies
• Lithofacies: Sandstone, Interbedded sandstone and shale

• Thickness: ca. 6,000 m
• Lower limit: Minami-Awa Fault

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

• Distribution: Mizoochi, Mugi city, Kaifu county, Tokushima pref.; Hiwasa, Minami city, Kaifu county, Tokushima pref.; Okiyadani - Hirai, Kaiyo city, Kaifu county, Tokushima pref.; Kawamata, Naka city, Naka county, Tokushima pref.
• Fossils (Radiolarians): Amphipyndax enesseffi, Amphipyndax tylotus, Cryptamphorella conara, Cryptamphorella macropora, Cryptamphorella sphaerica, Dictyomitra cf. andersoni, Dictyomitra koslovae, Dictyomitra multicostata, Pseudoaulophacus floresensis, Pseudoaulophacus lenticulatus, Pseudoaulophacus pargueraensis, Theocampe cf. abschnitta

• Hara et al. (2014) Geology of the Kitagawa District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, AIST, 72p. (in Japanese with English abstract 4p.)
• Tsujino et al. (2010) Jour. Geol. Soc. Japan, vol.116, no.12, pp.680-685 DOI
• Yamaguchi et al. (2009) Jour. Geol. Soc. Japan, vol.115, Supplement, pp.21-36 DOI
• Kiminami and Toda (2007) Jour. Geol. Soc. Japan, vol.113, no.4, pp.158-167 DOI