As shallow salt lake resources are increasingly exploited,deep confined brine has become a strategic alternative due to its widespread distribution and significant reserve potential.However,unfavorable reservoir chara...As shallow salt lake resources are increasingly exploited,deep confined brine has become a strategic alternative due to its widespread distribution and significant reserve potential.However,unfavorable reservoir characteristics,particularly low permeability and poor recovery efficiency,have historically rendered these deposits uneconomic,restricting their utilization.Taking the Mahai Salt Lake in the Qaidam Basin as a representative case,this study investigates the structural controls on brine enrichment through an integrated approach.Previous long-term metallogenic studies and exploration data indicate occurrences of an extensional fault zone favorable for brine accumulation.Therefore,we applied InSAR deformation analysis to assess coseismic and postseismic surface responses.Combined with radon-222 emanation mapping,our findings reveal a strong spatial correlation between high-productivity brine boreholes and active fault systems.The existence of active faults enhance brine migration and storage,provided that the target reservoirs have substantial halite thickness and maintain relatively low clay-silt content.展开更多
The mineral rock salts present in the Mahai Salt Lake of the Qaidam basin exhibit high solubilities in water. In addition, the multicomponent underground brine exhibits a high salinity and is easily precipitated. In t...The mineral rock salts present in the Mahai Salt Lake of the Qaidam basin exhibit high solubilities in water. In addition, the multicomponent underground brine exhibits a high salinity and is easily precipitated. In the natural state, brine transport in the brine layer is extremely slow, and the brine is in a relatively stable chemical equilibrium state with the rock salt media. However, during mining, both the seepage and the chemical fields fluctuate significantly, thereby disrupting the equilibrium and leading to variations in the chemical composition and dynamic characteristics of the brine. Therefore, we selected underground brine from the Mahai Salt Lake, collecting a total of 183 brine samples over three stages of mining（i.e., the early stage of underground brine extraction, the initial stage of mining, and the later stage of mining）. Using a range of analytical techniques, the chemical dynamics of the underground brine water and its evolution were systematically studied. We found that evaporation and enrichment were the main mechanisms of underground brine evolution in the Mahai Salt Lake, with cation exchange and mineral dissolution/precipitation being key factors in determining the dynamic characteristics and evolution of the brine.展开更多
柴达木盆地马海盐湖含钾地层下部沉积了厚层芒硝。与钾盐通常形成于干热气候不同,芒硝是典型的冷相盐类矿物,因此厚层芒硝的沉积特征及成因的研究对认识古环境演变过程及其对钾盐成矿影响具有重要意义。文章以柴达木盆地马海矿区发育的...柴达木盆地马海盐湖含钾地层下部沉积了厚层芒硝。与钾盐通常形成于干热气候不同,芒硝是典型的冷相盐类矿物,因此厚层芒硝的沉积特征及成因的研究对认识古环境演变过程及其对钾盐成矿影响具有重要意义。文章以柴达木盆地马海矿区发育的厚层芒硝的地层剖面为研究对象,通过系统取样开展薄片鉴定、化学组分、矿物类型和硫同位素分析,研究了剖面化学组分、矿物类型和硫同位素的变化规律。结果显示,该剖面的盐类矿物主要有石盐、石膏、芒硝及钙芒硝;芒硝层沉积的最大年龄为275.3±47.9 ka BP;剖面自下而上表现为由厚层纯净芒硝向含石膏石盐岩演变的特征,下部为芒硝层,中下部出现钙芒硝,中上部石盐含量最高,上部石盐含量相对减少,石膏含量增加,与之相对应的是沉积物化学组成中钾、镁和钙的含量稳定增高,硫酸根和钠含量总体降低。厚层芒硝沉积时期,马海盐湖处于持续干冷的气候条件,有利于盐湖卤水中钾、镁持续富集,为在局部富集形成固体钾矿奠定了基础。展开更多
基金supported by the National Key Research and Development Program Projects(2023YFC2906502 and 2018YFC0604801)。
文摘As shallow salt lake resources are increasingly exploited,deep confined brine has become a strategic alternative due to its widespread distribution and significant reserve potential.However,unfavorable reservoir characteristics,particularly low permeability and poor recovery efficiency,have historically rendered these deposits uneconomic,restricting their utilization.Taking the Mahai Salt Lake in the Qaidam Basin as a representative case,this study investigates the structural controls on brine enrichment through an integrated approach.Previous long-term metallogenic studies and exploration data indicate occurrences of an extensional fault zone favorable for brine accumulation.Therefore,we applied InSAR deformation analysis to assess coseismic and postseismic surface responses.Combined with radon-222 emanation mapping,our findings reveal a strong spatial correlation between high-productivity brine boreholes and active fault systems.The existence of active faults enhance brine migration and storage,provided that the target reservoirs have substantial halite thickness and maintain relatively low clay-silt content.
基金the support of the National Natural Science Foundation of China(41672243,41877198)
文摘The mineral rock salts present in the Mahai Salt Lake of the Qaidam basin exhibit high solubilities in water. In addition, the multicomponent underground brine exhibits a high salinity and is easily precipitated. In the natural state, brine transport in the brine layer is extremely slow, and the brine is in a relatively stable chemical equilibrium state with the rock salt media. However, during mining, both the seepage and the chemical fields fluctuate significantly, thereby disrupting the equilibrium and leading to variations in the chemical composition and dynamic characteristics of the brine. Therefore, we selected underground brine from the Mahai Salt Lake, collecting a total of 183 brine samples over three stages of mining（i.e., the early stage of underground brine extraction, the initial stage of mining, and the later stage of mining）. Using a range of analytical techniques, the chemical dynamics of the underground brine water and its evolution were systematically studied. We found that evaporation and enrichment were the main mechanisms of underground brine evolution in the Mahai Salt Lake, with cation exchange and mineral dissolution/precipitation being key factors in determining the dynamic characteristics and evolution of the brine.
文摘柴达木盆地马海盐湖含钾地层下部沉积了厚层芒硝。与钾盐通常形成于干热气候不同,芒硝是典型的冷相盐类矿物,因此厚层芒硝的沉积特征及成因的研究对认识古环境演变过程及其对钾盐成矿影响具有重要意义。文章以柴达木盆地马海矿区发育的厚层芒硝的地层剖面为研究对象,通过系统取样开展薄片鉴定、化学组分、矿物类型和硫同位素分析,研究了剖面化学组分、矿物类型和硫同位素的变化规律。结果显示,该剖面的盐类矿物主要有石盐、石膏、芒硝及钙芒硝;芒硝层沉积的最大年龄为275.3±47.9 ka BP;剖面自下而上表现为由厚层纯净芒硝向含石膏石盐岩演变的特征,下部为芒硝层,中下部出现钙芒硝,中上部石盐含量最高,上部石盐含量相对减少,石膏含量增加,与之相对应的是沉积物化学组成中钾、镁和钙的含量稳定增高,硫酸根和钠含量总体降低。厚层芒硝沉积时期,马海盐湖处于持续干冷的气候条件,有利于盐湖卤水中钾、镁持续富集,为在局部富集形成固体钾矿奠定了基础。
