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Oeyama Ophiolite

• Type locality: Mount Oe, Kyoto prefecture
• Ophiolite
• Forearc region of oceanic island arc?
• Paleozoic?
• Metamorphic rocks: Late Ordovician - Early Devonian (450 - 400 Ma)
• Amphibolite: Middle - Late Ordovician (469 - 444 Ma, K-Ar)
• Meta-gabbro: early Carboniferous (336 Ma, K-Ar)

• Matrix: Foliated serpentinite
• Tectonic blocks: Massive serpentinite, Tremolite rock, Basaltic greenstones, Dolerite, Gabbro, Chromitite, Rodingite, Pelitic metamorphic rocks, Jadeitite (Photo), Albitite

• Upper limit: Unconformity (Ipponmatsuyama Formation, Ishizaka Rhyolites, Kazafukidake Andesites)
• Lower limit: Thrust fault (Shiroumadake Formation)

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

• Distribution: Kotaki - Renge - Omi - Tonami - Kanayamadani valley - Mount Nagatsugayama - Shinadani, Itoigawa city, Niigata pref.; Happo ridge, Hakuba city, Kitaazumi county, Nagano pref.; Naratani, Kiyomi, Takayama city, Gifu pref.; Fukuji, Okuhidaonsengo, Takayama city, Gifu pref.; Ise, Ono city, Fukui pref.; Mount Oe, Kyoto pref.

• Takeuchi et al. (2017) Geology of the Tomari District, Quadrangle Series, Scale 1:50,000, Geological Survey of Japan, AIST, 121p. (in Japanese with English abstract 4p.)
• Machi and Ishiwatari (2010) Jour. Geol. Soc. Japan, vol.116, no.6, pp.293-308 DOI
• Igi and Kuroda (1965) Oeyama, Explanatory Text of the Geological Map of Japan, Scale 1:50,000, Geological Survey of Japan, 81p. (in Japanese with English abstract 12p.)