【摘要】 红岭钨矿床位于大东山-贵东岩浆岩带的南侧,产于燕山早期热水复式岩体的中部。在红岭钨矿区出露中细粒斑状黑云母花岗岩、细粒黑云母花岗岩和中细粒白云母花岗岩。三种花岗岩SiO₂含量为71.08%～75.53%,Na₂O+K₂O含量和A/CNK值分别介于7.50%～9.13%和0.97～1.42之间。其中斑状黑云母花岗岩和黑云母花岗岩属于过铝质花岗岩,而白云母花岗岩A/CNK>1.1,属于强过铝质花岗岩。锆石U-Pb年代学显示,黑云母花岗岩的年龄为161.6±1.3 Ma,白云母花岗岩的年龄为162.0±1.7 Ma,两者误差范围内一致,说明是同一岩浆活动的产物。同位素地球化学数据显示,三种花岗岩具有相似的Sr-Nd同位素组成,它们Sr同位素初始比值为0.7087～0.7214,ε_Nd（t）值为-15.9～-13.8,两阶段Nd模式年龄介于2065～2232 Ma之间,暗示成岩物质来自古元古代地层的重熔。元素地球化学研究显示,斑状黑云母花岗岩和黑云母花岗岩Nb/Ta值明显大于5, Zr/Hf>25, Y/Ho值<28;而晚期白云母花岗岩Nb/Ta值明显小于5, Zr/Hf<25值, Y/Ho>28。因此,红岭钨矿区三种花岗岩是同一S型花岗质岩浆不同演化阶段的产物,由早期到晚期花岗质岩浆挥发分的饱和程度逐增加,而含矿的细粒白云母花岗岩则是晚期富挥发分残余岩浆固结的产物。岩浆晚期阶段,挥发分的高度聚集可能是导致钨超常富集的关键因素。更多还原

【Abstract】 The Hongling tungsten deposit is located in the central part of the Reshui complex, south of the DadongshanGuidong batholith. The granites exposed in the Hongling deposit include fine-grained biotite granite, medium-grained biotite granite, and medium-fine grained muscovite granite. The granites have geochemical features similar to those of typical tungsten-bearing granites in South China. They have SiO₂ contents varying from 71.08% to 75.53%, with Na₂O+K₂O contents and A/CNK values varying from 7.50% to 9.13% and 0.97 to 1.42, respectively. The biotite granites are peraluminous, whereas the muscovite granite is strong peraluminous. Zircon U-Pb dating yielded ages of 161.6±1.3 Ma for the fine-grained biotite granite and 162.0±1.7 Ma for the muscovite granite, respectively. The granites have narrow ranges of Sr-Nd isotopic compositions, showing relatively high initial ⁸⁷Sr/⁸⁶Sr ratios（0.7087 to 0.7214） and negative ε_Nd（t） values（-15.9 to-13.8）, and two-stage model ages of 2065 Ma to 2232 Ma. It is suggested that they derived from partial melting of Paleoproterozoic meta-sedimentary rocks. The whole-rock Nb/Ta and Zr/Hf ratios decrease from the biotite granites to muscovite granite, while their Y/Ho ratios increase. We argue that the overall granites in the Hongling deposit are S-type granites that experienced different degrees of fractionation. The super-enrichment of tungsten is possibly related to the concentration of volatile components in the late stage of granite evolution.更多还原