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五龙沟金矿位于东昆仑中段,是该区重要的造山型金矿。区内侵入岩非常发育,针对五龙沟金矿红旗沟矿段早志留世二长花岗岩的锆石U-Pb定年和岩石地球化学分析。结果表明该岩体形成年龄为438 Ma±2.8 Ma,岩石地球化学特征显示富硅(68.13%~71.14%)、富碱[w(Na_2O+K_2O)=7.81%~8.43%]、富钾(Na_2O/K_2O=0.70~0.75),贫Al_2O_3,Fe_2O_3,MnO和MgO等特征。稀土总量较高,轻、重稀土分馏及Eu负异常较明显;Rb,Th,K,Pb的相对富集,Sr,P,Ti强烈亏损,暗示其岩浆应起源于成熟度相对较高的中酸性陆壳物质的部分熔融。结合区域上的研究成果,认为该期岩浆活动很可能与早志留世东昆仑洋盆主体关闭和陆壳开始俯冲碰撞有关。
Wulonggou gold mine is located in the middle of East Kunlun, which is an important orogenic gold mine in this area. The intrusive rocks in the area are well developed. According to the U-Pb zircon dating and lithogeochemical analysis of the Early Silurian granite in the Hongqigou deposit, Wulonggou gold deposit, The results show that the age of the rock mass is 438 Ma ± 2.8 Ma, and the geochemical characteristics of the rock mass are rich in silicon (68.13% -71.14%) and Na 2 O 4 (7.81% ~ 8.43% /K_2O=0.70~0.75), poor Al_2O_3, Fe_2O_3, MnO and MgO and other characteristics. The total rare earth content is higher, and the light and heavy rare earth fractionation and Eu negative anomalies are obvious. The relative enrichment of Rb, Th, K and Pb, and the strong depletion of Sr, P and Ti suggest that the magma should originate from relatively high maturity Part of mid-acidic continental crustal material melts. Based on the research findings in the area, it is concluded that the magmatic activity in this period is probably related to the closure of the main body of the East Kunlun Ocean in the Early Silurian and the collision of continental crust.