Advances in Earth Science ›› 2016, Vol. 31 ›› Issue (2): 180-191. doi: 10.11867/j.issn.1001-8166.2016.02.0180.
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Wanfeng Chen 1( ), Gang Guo 2, Xiuquan Miao 1, Jinrong Wang 1, *( ), Wanlong Hu 1, Binbin Zhao 3, Lifei Fan 4
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First author:Chen Wanfeng(1990-), male, Gulang County, Gansu Province, Ph.D Candidate. Research areas include lithospheric evolution and mineralization.E-mail:chenwf14@lzu.edu.cn
Corresponding author:Wang Jinrong(1958-), male, Putian City, Fujian Province, Professor. Research area include petro-tectonic.E-mail:jrwang@lzu.edu.cn
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Wanfeng Chen, Gang Guo, Xiuquan Miao, Jinrong Wang, Wanlong Hu, Binbin Zhao, Lifei Fan. Geochemical Characteristics and Tectonic Significance of Early Carboniferous Volcanic Rocks of Kalamaili, Xinjiang[J]. Advances in Earth Science, 2016, 31(2): 180-191.
Shanlianglishi Formation strata volcanic rocks are widely distributed in western fault zone of Kalamaili. Studies show that the rocks are basalt, andesite and basaltic andesite, calc-alkaline series with SiO2 content of samples ranging from 49.43% to 59.08%, TiO2 (1.18%~2.49%), P2O5 (0.21%~0.92%) and MgO (3.81%~6.28%). Samples have relatively high HFSE content (Ti, Zr, Y) and also high La/Nb (2.98~1.96), Zr/Y (9.36~4.01) ratio. The primitive mantle normalized trace element spider shows samples enriched LILE (Rb, Ba, K, U) and Pb, but relatively depleted Nb, Ta and Ti. Rare earth element distribution of REE shows slightly enriched LREE, (La/Yb)N=1.93~9.59, and that Eu is weakly negative anomaly (δEu=0.87~0.95). Combined with geochemical characteristics of WPB and VAB. Shanlianglishi Formation strata formed in the stretched after collision environmen. After partial melting of the enriched mantle that was previously metasomatized by the subduction fluid and with participation of the subduction sediment, magma experienced a certain degree of fractional crystallization and contamination by earth crust, and then erupted to form the Shanlianglishi Formation strata volcanic rocks. In eraly Late-Carboniferous, extensional movement was the most intense volcanic activity, which reached its peak in this area.