中文摘要：

赛什塘-日龙沟以铜为主的多金属矿田位于东昆仑与西秦岭的交接部位,分布有大量中酸性侵入体,与成矿作用有密切关系。通过对日龙沟锡多金属矿区花岗闪长岩LA-ICP-MS锆石U-Pb同位素和岩石地球化学研究,认为该岩体形成于中三叠世（230.7±1.5Ma）,属于相对贫硅（Si O2含量为62.24%-63.67%）、偏碱（碱度率AR为1.73-1.88）、过铝（铝饱和指数A/CNK介于2.37-2.70之间）的花岗闪长岩。稀土元素总量较高（∑REE=111×10^-6-164×10^-6）,稀土元素配分曲线呈轻稀土元素富集（LREE/HREE=9.83-16.95）的右倾曲线,（La/Yb）N介于16.5-34.32之间,Eu、Gd具有弱负异常（δEu=0.79-0.98,δGd=0.73-0.81）,而Tb具有弱正异常（δTb=1.23-1.28）。微量元素显示,Rb、Ba、Th、U等大离子亲石元素相对富集,Nb、Ta、Dy、Y、Ho、Yb、Lu等高场强元素亏损。岩相学特征显示,岩体主要由斜长石、黑云母、石英及角闪石组成;镜下可见2组斜长石及包含结构。综合判断认为,日龙沟花岗闪长岩体属I型花岗岩,可能是二叠系中性火山岩部分熔融形成的。结合野外地质调查,初步认为赛什塘-日龙沟矿田具有2期成矿作用。

英文摘要：

Located at the junction between the Eastern Kunlun Mountains and the western Qinling Mountains, the Sertang-Pdlong- gou area is a polymetaUic orefield in Qinghai province, related mainly to copper mineralization. In this area, acidic intrusive bodies are extensively distributed and have a deep effect on the mineralization there. Through the research on the LA-ICP-MS zircon U- Pb dating and geochemistry of biotite granodiorite, the authors found that the rock mass of the Sertang-Rilonggou area was formed in the Triassic, and it also has the features of relatively poor silicon （the content of the SiO2 is 62.24%±63.67%）, strong alkali （the rate of the alkalinity is 1.73-1.88）, and excessive aluminum （the A/CNK is 2.37-2.70）. On the diagram of SiO2-（K2O ＋Na2O）, graphic sample is pointed to the alkaline series of granodiorites zone. And in this polyrnetallic orefield, the amount of the rare earth elements is low （∑ REE=111 × 10^-6-164×10^-6）, and the rare earth element distribution curve shows that the light rare earth elements are of enrichment （LREE/HREE=9.83-16.95） with the curve right-oblique. The average （La/Yb）N is 21.13; the Eu and Gd have the feature of a weak negative anomaly （ 8 Eu=0.79-0.98, δ Gd=0.73-0.81）, while the element of Tb has the feature of a positive anomaly （ δ Tb=1.23-1.28）. An analysis of the trace elements shows that Rb, Ba, Th, U and some other large ion lithophile elements exhibit relative enrichment, some high field-strength elements, such as Nb, Ta, Dy, Y, Ho, Yb, and Lu are deficient, and the values of some elements like Pb, Sn are relatively high. This rock mass is mainly composed of plagioclase, quartz and hornblende. Under the microscope, two groups of plagioclase and poikilitic texture can be observed. The synthetic judgment of these features has led the authors to believe that this rock mass is of type I granite, resulting from intermediate-volcanic rock melt in Permian. Combined with the field investigation, It is held that the Sertang-l