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卡尔却卡铜多金属矿区似斑状二长花岗岩体与成矿关系密切。LA-ICP-MS锆石U-Pb结果表明岩体形成时代为220.4 Ma±0.79Ma(MSWD=0.30)。岩石地球化学特征显示其属于准铝质(ACNK=0.93~1.04)、高钾钙碱性-钾玄岩系列,具有大离子亲石元素富集、高场强元素亏损、轻稀土富集、负Eu异常中等(σEu介于0.47~0.70之间)等特征。岩体(~(87)Sr/~(86)Sr)_ⅰ值为0.710 71~0.713 66,平均0.711 52,εNd(t)值为-3.6~-5.4,平均-4.1,T_(2DM)=1.29-1.44Ga,平均1.36Ga。考虑到本区中晚三叠是花岗岩类普遍含大量暗色镁铁质包体,具有明显的岩浆底侵和混合的证据,且样品Sr-Nd同位素显示富集地幔源区特征,认为似斑状二长花岗岩形成于晚三叠世后碰撞阶段,岩浆起源于富集地幔的基性岩浆底侵并与古老陆壳发生混合,幔源岩浆活动与成矿作用关系密切,解释了东昆仑地区成矿作用主要与中晚三叠世岩浆活动有关。
Karl Zuka copper polymetallic ore-like porphyritic monzonitic granite body is closely related to metallogenesis. LA-ICP-MS zircon U-Pb results show that the formation time of the rock mass is 220.4 Ma ± 0.79Ma (MSWD = 0.30). The geochemical characteristics of the rocks show that they belong to the quasi-aluminum (ACNK = 0.93 ~ 1.04), high-K calc-alkaline-potassium basalt series with large ion lithophile enrichment, high field strength element depletion, light rare earth enrichment, negative Eu anomalies moderate (σEu between 0.47 to 0.70) and other characteristics. The value of ~ (87) Sr / ~ (86) Sr) _i is 0.710 71 ~ 0.713 66 with an average of 0.711 52 and εNd (t) is -3.6 ~ -5.4, average -4.1 and T 2DM = 1.29 -1.44Ga, an average of 1.36Ga. Considering that the middle Triassic and the Late Triassic in this area are generally rich in dark mafic inclusions, with evidence of magmatic underplating and mixing, and the samples Sr-Nd isotopes show enrichment of mantle source features, The long granites were formed in the Late Triassic post-collision stage. The magma originated from enrichment of the mantle beneath the basic magma and mixed with the ancient continental crust. The mantle magmatism is closely related to metallogenesis and explained the mineralization in the East Kunlun area The role is mainly related to the magmatic activity of Middle and Late Triassic.