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本文系统地研究了黔西南晴隆锑矿床中萤石的稀土元素地球化学 ,表明不同颜色、不同矿物组合的萤石的稀土元素含量变化较大 ,但具有固定的REE分配模式 ,以明显的负Ce异常、富MREE、分配曲线相对平缓为特征 ;这种配分模式主要是受其晶体化学因素的控制 ,而与溶液中REE络合物的稳定性关系不大。萤石的稀土元素组成与其矿物共生组合关系不大 ,但与其颜色关系较密切。萤石的Ce、Eu异常主要是受氧逸度的控制 ,流体源区的氧逸度较高 ,矿物沉淀场所的氧逸度相对较低 ,从而导致该矿中萤石呈明显的负Ce异常 ,或正或负的Eu异常。晴隆锑矿床形成于开放体系条件下 ,水 岩反应很可能是导致萤石发生沉淀的主要机制。萤石中的Ca部分来自茅口组灰岩 ,部分来自大厂层玄武岩 ;而矿化剂F可能主要来自外部。
In this paper, we systematically studied the REE geochemistry of fluorite in the Qinglong antimony deposit in the southwestern Guizhou Province. It shows that the REE content of the fluorite with different color and mineral assemblages varies greatly, but has a fixed REE distribution pattern with obvious negative Ce anomaly and MREE rich, and the distribution curve is relatively flat. This pattern of partitioning is mainly controlled by the crystallographic factors, but has little to do with the stability of REE complexes in solution. The composition of rare earth elements of fluorite has little to do with the symbiosis of its minerals, but it is closely related to its color. The anomalies of Ce and Eu in fluorite are mainly controlled by the oxygen fugacity, and the oxygen fugacity in the fluid source region is relatively high, and the oxygen fugacity in the place where the minerals are deposited is relatively low, resulting in obvious negative Ce anomaly in the fluorite in the mine , Or positive or negative Eu anomaly. Qinglong antimony deposit formed under the open system conditions, water-rock reaction is likely to be the main mechanism leading to the occurrence of fluorite precipitation. Fluorite part of the Ca from Maokou limestone, part from the Dachang basalt; mineralizer F may be mainly from the outside.