红花尔基白钨矿矿床为内蒙古大兴安岭中北段地区新发现的一处钨矿规模接近大型的W-Mo矿床。文章通过系统的岩相学、矿相学、流体包裹体和碳、氢、氧同位素研究,表明红花尔基白钨矿矿床属岩浆期后热液充填-交代矿床,可划分为钾长石、钠长石阶段→白钨矿-石英阶段→辉钼矿-石英阶段→铜、铁、铅、锌硫化物-石英阶段→碳酸盐-石英阶段5个成矿阶段。矿床内的白钨矿、石英以及碳酸盐中的流体包裹体均以富液相气液两相水溶液包裹体为主。白钨矿-石英阶段的均一温度范围为290-395℃,峰值为360-370℃,盐度w(Na Cleq)范围为0.88%-7.02%,峰值为2%-3%,结合包裹体激光拉曼分析,得出与钨矿形成有关的流体为中高温、低盐度的Na Cl-H2O体系的结论。白钨矿和石英的H-O以及碳酸盐的C-H-O同位素特征表明,成矿流体主要是岩浆水,并有少量大气降水的混合。成矿流体为岩浆结晶分异作用形成的富钨等成矿元素的热液。矿区花岗岩的云英岩化可能将钙萃取进入流体,参与白钨矿结晶、沉淀。
The Honghuaerji scheelite deposit is a newly discovered large W-Mo deposit in the middle and northern Da Hinggan Mountains, Inner Mongolia. Ore petrography, fluid inclusions and C-H-O isotopic compositions show that the Honghuaerji deposit was formed by post-magmatic hydrothermal process, which can be divided into five oreforming stages: potassic feldspar-albite stage, scheelite-quartz stage, molybdenite-quartz stage, Cu-Pb-Zn-Fe metal sulfides-quartz stage and carbonate-quartz stage. The fluid inclusion types in scheelite, quartz and carbonate are mainly liquid-rich two-phase inclusions. The data show that the homogeneous temperatures of fluid inclusions of the scheelite-quartz stage are 290 - 395℃, with the peak of 360 - 370℃, and the salinities are 0. 88% - 7. 02%,with the peak of 2% - 3%. Combined with the Laser Raman analysis of the fluid inclusions, the authors have reached the conclusion that the scheelite-related fluids were of the medium-high temperature and low salinity Na ClH2 O fluid system. An analysis of C-H-O isotope reveals that the hydrothermal fluids were mainly of magmatic hydrothermal fluids, mixed with a little meteoric water. Studies indicate that the fluid related to tungsten mineralization might have been derived mainly from crystallization and differentiation of magma, and the Ca2 +was probably released from the plagioclase by greisenization.