基于质量平衡计算对甘肃龙首山红石泉铀矿热液蚀变成矿作用的研究

Research on the hydrothermal alteration and mineralization of Hongshiquan uranium deposit in Longshoushan area,Gansu based on mass balance calculation

红石泉矿床是甘肃省龙首山地区重要的铀矿床,但以往的研究对红石泉地区热液蚀变研究往往局限于定性分析,为了定量确定其对铀成矿作用的影响,本次研究首次引入质量平衡算法,通过对红石泉地区新鲜伟晶状花岗岩与蚀变伟晶状花岗岩的对比分析,在本地区热液蚀变对铀矿床的形成起到的作用进行了定量研究。研究表明,红石泉矿床铀成矿经历了至少二次成矿作用,其中部分矿段热液蚀变迁入的U元素达到原生的36倍以上,说明热液蚀变对铀成矿起到了至关重要的作用;同时从机理上阐述了热液蚀变产生的赤铁矿化等蚀变可以作为找矿指示标志的原因。

Hongshiquan deposit is one important uranium deposit in the Longshoushan area of Gansu Province.However,previous researches have often been limited to qualitative analysis on hydrothermal alteration in Hongshiquan area..In this study,the mass balance algorithm is introduced for the first time to quantitatively investigate the role of hydrothermal alteration in the formation of the uranium deposit in Hongshiquan area with the comparison of fresh and altered pegmatite granite.The study result indicates that the deposit has undergone at least two hydrothermal alteration stages,characterized by potassium feldspathization and sodium feldspathization,respectively.U element mobilized by hydrothermal alteration in some ore sections exceeds the original content by more than 36 times,indicating the significant role of hydrothermal alteration in uranium mineralization.Additionally,the mechanism explains why the alteration caused by hydrothermal alteration,such as hematite mineralization,can serve as an indicator for mineral exploration.