Advances in Earth Science
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Wang Yuwang 1,2, Wang Jingbin 1,2, Tang Pingzhi 1, Zhao Lutong 2, Shi Yu 3, Chen Yanfei 3
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Wang Yuwang,Wang Jingbin, Tang Pingzhi, Zhao Lutong, Shi Yu, Chen Yanfei. Geology and Geochemistry of Basalt in the Kekesentao Ophiolite, Xinjiang[J]. Advances in Earth Science, DOI: 10.11867/j.issn.1001-8166.2012.10.1100.
The newlyfound Kekesentao basalt occures in the north of the Kekesentao ultramafic complex, north Xinjiang. It is composed of basalt and basaltic tuff with thickness of 50 to 80 meters. The basalt generally undergoes schistosition, but porphyritic structure still remained. The geochemistry of rocks shows that the basalt is low alkali (Na2O+K2O<3%, σ=0.60-1.19), low titanium (TiO2=0.73%-1.22%) and magnesiumrich (MgO=7.43%-9.72%) tholeiitic rock series, and might be generated from primary magma characterized by Mg# value of 0.65 to 0.71. The characteristics of low REE contents (ΣREE=29.68×10-6-44.91×10-6), and flat REE and trace elements normalized pattern of the basalt suggest that it form in middleocean ridge tectonic setting. The discovery and geochemical research of the basalt proves the existence of Kekesentao ophiolite suite.