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新疆西准噶尔苏云河地区发育有斑岩型(铜-)钨钼共生矿床,通过对矿区内Ⅰ#含矿岩体进行详细的岩石学、地球化学及锆石U-Pb年代学研究,探讨岩浆起源、构造背景及其成矿意义。结果表明:(1)岩体高Si O2、Al2O3,中等富碱且相对富钠,A/CNK=1.08~1.28,σ=1.52~1.81,属钙碱性(强)过铝质花岗岩;稀土含量较低(∑REE=33.77×10-6~92.91×10-6),轻重稀土分馏程度中等且富集轻稀土((La/Yb)N=5.13~9.69),具弱Eu负异常(δEu=0.62~0.92);相对富集Rb、Th、U、K等LILE和LREE,亏损Ba、Sr、P、Ti、Nb、Ta和HREE等;(2)锆石LA-ICP-MS U-Pb定年获得岩浆结晶年龄为308.8±4.1Ma,岩体侵位时代为晚石炭世;(3)岩体具有正的εNd值(εNd=3.64~6.33)、低的87Sr/86Sr初始比值(ISr=0.704009~0.705313)和较年轻的二阶段模式年龄(t2DM=0.52~0.70Ga),形成于晚石炭世洋内俯冲背景下、有俯冲流体及少量洋盆陆源碎屑沉积物参与的晚元古代玄武质洋壳的部分熔融;(4)苏云河地区晚石炭世浅成岩浆侵入活动同时是一期重要的斑岩型(铜-)钨钼成矿事件,Ⅰ#岩体深部及巴尔鲁克断裂以西石炭纪中酸性岩体的含矿性值得做进一步评价。
A porphyry type (copper -) tungsten-molybdenum symbiotic deposit has been developed in the West Saikur region of Yunan, Xinjiang. Based on the detailed petrology, geochemistry and zircon U-Pb dating of ore body I # in the area, , Tectonic setting and its metallogenic significance. The results show that: (1) high Si O2, Al2O3, medium alkali rich and relatively rich in sodium, A / CNK = 1.08-1.28 and σ = 1.52-1.81, (ΣREE = 33.77 × 10-6 ~ 92.91 × 10-6), light and heavy rare earths are moderately fractionated and enriched in light rare earth (La / Yb) N = 5.13 ~ 9.69) 0.62 ~ 0.92); relatively enrichment of LILE and LREE such as Rb, Th, U, K and depletion of Ba, Sr, P, Ti, Nb, Ta and HREE; (2) LA-ICP- The age of the magma was 308.8 ± 4.1Ma and the emplacement time of the rock mass was Late Carboniferous. (3) The rock mass had a positive εNd value (εNd = 3.64 ~ 6.33) and a low 87Sr / 86Sr initial ratio (ISr = 0.704009 ~ 0.705313) and the younger two-stage model age (t2DM = 0.52 ~ 0.70Ga) formed in the Late Carboniferous oceanic subduction background with the involvement of subduction fluids and a small amount of oceanic terrigenous clastic sediments in the Late Proterozoic basaltic ocean (4) The Late Carboniferous epithermal intrusions in the Suyunhe area are also an important porphyry (copper-) tungsten-molybdenum mineralization event at the same time. In the deep part of the I # rock mass and west of the Barruk fracture, the Carboniferous The mineralization of moderately acidic rocks deserves further evaluation.