地质通报2016，Vol.35Issue(7)：1170-1183,14.
新疆东准乌须克劳格岩体LA-ICP-MS锆石U-Pb年龄、Hf同位素特征及其地质意义
LA-ICP-MS zircon U-Pb ages and Hf isotopic characteristics of Wuxukelaoge pluton in East Junggar Basin of Xinjiang and their geological significance
摘要
Abstract
Thanks to prospecting breakthrough in recent years, a series of important mineral resources have been found in Qiongheba area, East Junggar Basin, Xinjiang, which are essentially distributed around Wuxukelaoge pluton. The pluton is the largest in the re⁃ gion and it has a complex composition, mainly comprising granodiorite and monzonitic granite. In this paper, U-Pb dating of LA-ICP-MS zircon was used to investigate the age of the pluton. It is shown that granodiorite is 428.9±1.9Ma and monzonitic granite is 427.2±1.7Ma in age, suggesting that the two ages represent the ages of rocks that contain the zircon. Both the granodiorite and mon⁃zonitic granite are of peraluminous and calc-alkaline series with high Al2O3 (15.87%~18.77%), CaO (2.92%~6.82%) and low K2O/Na2O ratios (0.15~0.40);The pluton has low total REE content (57.33×10-6~72.13×10-6) with relative enrichment of LREE and ob⁃scure Eu negative anomaly (δEu=0.79~1.06). The primitive mantle normalized trace element patterns are characterized by the deple⁃tion of the HFSE (Th, Nb, Ta, P, Ti) and enrichment of the LILE (Rb, Ba, U, K, Sr). High Ba (230×10-6~682×10-6), Sr(851.8×10-6~1020.1×10-6), high (La/Yb)N(6.0~10.1), Sr/Y(70.0~106.4) ratios, and distinct Nb all suggest features of high Ba-Sr granitoids. The test results of Hf isotope show that Wuxukelaoge pluton has high and positive εHf(t) values(14.28~17.54) and younger model age. These geochemical and Hf isotope characteristics indicate that the pluton was formed in a continental margin arc setting and related to partial melting of subducted oceanic crust.关键词
LA-ICP-MS锆石U-Pb年龄/地球化学/Hf同位素/乌须克劳格岩体Key words
LA-ICP-MS zircon U-Pb dating/geochemistry/Hf isotopes/Wuxukelaoge pluton分类
天文与地球科学引用本文复制引用
李高峰,孟贵祥,吴建,姜彦勇,雷印祥,童英..新疆东准乌须克劳格岩体LA-ICP-MS锆石U-Pb年龄、Hf同位素特征及其地质意义[J].地质通报,2016,35(7):1170-1183,14.基金项目
中国地质调查局项目（编号1212011085024、12120113041300）和新疆维吾尔自治区地质勘查基金项目 （）
