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Haroku Formation

• Accretionary complex
• early - middle Eocene (Radiolarians)
• Intruded by (Lower): Felsic pyroclastic dikes

• Sedimentary facies: Marine
• Sedimentary facies: Submarine fan
• Lithofacies (Upper): Sandstone, Sandstone-dominant interbedded sandstone and mudstone
• Lithofacies (Upper, Minor): Conglomerate
• Lithofacies (Lower): Mudstone-dominant interbedded sandstone and mudstone
• Lithofacies (Lower, Minor): Sandstone-dominant interbedded sandstone and mudstone, Sandstone, Conglomerate, Gravel-bearing mudstone, Felsic tuff
• Sedimentary structures (Upper): Graded bedding, Parallel stratification, Flute marks, Groove marks, Wave ripples, Slump structures
• Sedimentary structures (Lower): Graded bedding, Parallel stratification, Cross stratificaation, Flute marks, Groove marks, Slump structures
• Paleocurrent (Upper, Longitudinal current flow): from East to West
• Paleocurrent (Lower, Longitudinal current flow): from North to South, from East to West, from Northeast to Southwest
• Paleocurrent (Lower, Lateral current flow): from Southeast to Northwest, from South to North

• Thickness (Upper): 300 - 550 m or thicker
• Thickness (Lower): 320 - 1,000 m
• Upper limit: Gobo-Totsukawa Thrust fault
• Lower limit: Bottom of the horizon of interbedded sandstone and mudstone
• Lower limit: Conformity (Uridani Formation)

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

• Distribution: Maruyama - Cape Kirime - Cape Hatano, Inami city, Hidaka county Wakayama pref.; Fudono - Tondagawa river - Hikigawa river - Otonashigawa river - Mikoshigawa river - Kumondani valley - Narukawadani valley - Sakayasu - Hyogi - Hiromigawa river - Chikatsuyu - Fukusada - Kurisugawa river - Mount Masagiyama, Tanabe city, Wakayama pref.
• Fossils: Radiolarians

• Tokiwa et al. (2016) Jour. Geol. Soc. Japan, vol.122, no.12, pp.625-635, DOI
• Bessho and Nakaya (2011) Jour. Geol. Soc. Japan, vol.117, no.8, pp.423-438 DOI
• Tokuoka et al (1981) Geology of the Ryujin District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 69p. (in Japanese with English abstract 6p.)
• Suzuki et al (1979) Geology of the Kurisugawa District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, 54p. (in Japanese with English abstract 5p.)