西华山钨矿床晶洞中水晶与黑钨矿流体包裹体显微测温与特征元素测定  

Microthermometry and characteristic element determination for the fluid inclusions in the wolframite and quartz in the drusy cavities of Xihuashan tungsten deposit

作　　者：黄惠兰 常海亮 李芳 谭靖 张春红 周云 杨科[2] 闫芬[2] 

机构地区：[1]武汉地质矿产研究所,湖北武汉420235 [2]中国科学院上海应用物理研究所,上海201204

出　　处：《地学前缘》2013年第2期205-212,共8页Earth Science Frontiers

基　　金：国土资源部公益性行业科研专项项目(200911043-04)

摘　　要：西华山钨矿床晶洞中水晶与黑钨矿以及晶洞外部块状石英与共生黑钨矿中流体包裹体对比研究结果表明,后期应力作用和流体改造是造成共生石英与黑钨矿包裹体均一温度出现重大差异的主要原因。一般来说,在后期应力作用和流体改造下,黑钨矿有较好的稳定性,能较好地保存原生包裹体和较少出现次生包裹体,而与之共生石英中的原生包裹体几乎破坏殆尽,现在所看到的包裹体绝大部分是后来形成的次生包裹体,且很难确切区别原生与次生关系。当后期应力作用和流体改造很微弱时,石英中可保存较多原生包裹体,并且原生与次生关系较易区分。当完全未受应力作用改造时,共生石英(水晶)与黑钨矿中都只有原生包裹体,其Th值和盐度值基本相同或完全一致,且石英(水晶)流体包裹中富含W、Mn、Fe等成矿元素,表明石英与黑钨矿是由同一流体在相同时间和相同条件下沉淀的。鉴于一般金属矿床皆在一定程度上经受了后期应力作用和流体改造,因此在有关流体包裹体研究中应该结合不透明矿物进行全面对比,并且切实加强岩相学研究。In Xihuashan tungsten deposit, the fluid inclusions in quartz and wolframite inside the drusy eavities show significant difference in homogenization temperature of the coexisting quartz and wolframite by contrast with the fluid inclusions in massive quartz and wolframite outside the drusy cavities, which is mainly caused by post metallogenic stress and the alteration of fluids. In general, under post metallogenic stress and alteration by fluids, the wolframite is stable and is able to preserve primary inclusions with less secondary inclusions; while the primary inclusions in the coexisting quartz are nearly destroyed, most of the inclusions that we can see now are secondary inclusions formed subsequently, and it is difficult to distinguish between the primary and secondary ones. If the post metallogenic stress and the alteration of fluid were weak, more primary inclusions could be preserved in quartz and the primary--secondary relationship would be easier distinguished. If it was not affected by the stress, there are only primary inclusions in the coexisting quartz （crystal） and wolf ramite, and their Th and salinity values are similar or consistent, and, moreover, the fluid inclusions in quartz （crystal） are rich in W, Mn, Fe and other mineralizing elements, indicating that the quartz and wolframite were deposited by the same fluid at the same time and under the same conditions. Considering that the metal ore deposits are generally subjected to post metaliogenic stress and the alteration of fluids, and, therefore, the study of fluid inclusion should be combined with opaque mineral study and careful petrographic observations.

关 键 词：红外显微镜 共生石英(水晶)与黑钨矿 大脉型黑钨矿床 流体包裹体显微测温 后期应力作用与流体改造 江西西华山 

分 类 号：P618.67[天文地球—矿床学]