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关于金顶铅锌矿的成矿时代至今未获得精确的同位素测年数据,这严重制约了我们准确厘定该矿的成矿动力学背景。鉴于此,本文根据黄铁矿的产状特征,将其区分为沉积成岩期和热液期黄铁矿,并开展了Re-Os同位素测年的研究(ICP-MS方法)。虽然黄铁矿的R(e0.4069×10-9～375.2620×10-9)和O(s 0.0008×10-9～0.4131×10-9)含量变化很大,部分样品含量很低,但它们仍然揭示出两组等时线年龄:分别为114±13 Ma和65±10 Ma。笔者认为114 Ma等时线年龄可能代表了沉积成岩过程当中的一期矿化年龄,而65 Ma可能记录了铅锌主矿化之前热液作用开始活动的时间。结合其他方面的地质证据推断金顶铅锌矿主矿化时代可能在28～37 Ma之间。
Up to date, no accurate isotope dating data have been obtained on the metallogenic epoch of Jinding lead-zinc mine, which severely restricted our accurate determination of the ore-forming kinetic background. In view of this, according to the characteristics of pyrite, this paper divides it into pyrite and hydrothermal pyrite, and studies the Re-Os isotope dating (ICP-MS method). Although the contents of R (e0.4069 × 10-9 ~ 375.2620 × 10-9) and O (s) in pyrite vary greatly, some samples are very low in content, but they Still reveal two sets of isochron age: 114 ± 13 Ma and 65 ± 10 Ma respectively. The author believes that the 114 Ma isochron age may represent the first stage of mineralization in sedimentary diagenesis and 65 Ma may record the time when hydrothermal interaction started to take place before the main lead-zinc mineralization. Combined with other aspects of the geological evidence infer Jinding lead-zinc ore main mineralization may be between 28 ~ 37 Ma.