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Mikabu Unit, Mikabu Green Rocks

The name of this geological unit, Mikabu, is different from the name of the type locality.

• Type locality: Mount Mikabo, Kanna city and Fujioka city, Gunma prefecture
• High P/T metamorphic rocks
• Deposition: Middle - Late Jurassic
• Deposition (Shale): Jurassic
• Metamorphism (Greenschist facies): Late Cretaceous (83.5 - 78.3 Ma, K-Ar)
• Accretion: Late Jurassic or later
• Metamorphic zones: Chlorite zone

• Sedimentary facies: Submarine volcano
• Metamorphic facies: Pumpellyite-Actinolite, Greenschist, Blueschist
• Lithofacies (Upper): Mudstone, Siliceous mudstone
• Lithofacies (Upper, Minor): Gabbro, Basalt (Lava, Hyaloclastite), Ultramafic rocks (Serpentinite)
• Lithofacies (Lower): Gabbro, Basalt lava (Pillow lava), Dolerite, Hyaloclastite, Volcaniclastic rocks
• Lithofacies (Lower, Minor): Chert, Siliceous mudstone
• Lithofacies (Minor): Pelitic schist, Limestone, Serpentinite, Dunite, Wehrlite

• Thickness: 1,500 - 1,700 m
• Upper limit: Aridagawa Tectonic Line (Wakayama) (Chichibu Belt)
• Lower limit: Unknown

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

• Distribution: Mount Mikabo, Gunma pref.; Yuzurihara, Onishi, Fujioka city, Gunma pref.; Iyo - Taiho - Asahine - Sadamine river, Higashichichibu city, Saitama pref.; Kiroko - Suguro, Ogawa city, Hiki county, Saitama pref.; Akiyama - Yatsu - Tomita - Nishinoiri, Yorii city, Osato county, Saitama pref.; Sadamine pass, Chichibu city, Saitama pref.; Mount Hotosan, Nagatoro, Chichibu city, Saitama pref.; Mount Minoyama, Minano city, Chichibu county, Saitama pref.; Kanaya - Shimizu, Aridagawa city, Arida county, Wakayama pref., Ozu city, Ehime pref.

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