新疆罗布泊富钾卤水矿床异常富集机理

罗布泊是世界上最大的单体硫酸盐型液体钾盐矿床,对于其矿床成因一直存在争议.基于大量盐泉、地下潜水及地表水的化学实测数据,从水文化学的角度探讨罗布泊富钾卤水矿床成因.结果表明,矿区富钾卤水钠氯系数为0.76～1.24,钾氯系数为38.58～60.49,主体表现为溶滤型卤水特征,指示有其他来源卤水混合参与成矿;首次在罗布泊...

Abnormal Enrichment Mechanism of Potassium-Rich Brine Deposit in Lop Nor Basin of Xinjiang

Lop Nor is the largest single sulfate-type liquid potash deposit in the world, and the genesis of the deposit has been controversial. In this paper, the genesis of potassium-rich brine deposits in Lop Nor is discussed from the perspective of hydrochemistry, based on a large number of measured chemical data of salt springs, underground phreatic water and surface water. The results show that the sodium-chlorine coefficient of potassium-rich brine is 0.76-1.24, and the potassium-chloride coefficient is 38.58-60.49. The main body of the brine shows the characteristics of dissolving-filtering brine, indicating the mixing of brine from other sources. It is the first time that Ca-Cl type brine is found in the eastern fault zone of Lop Nor basin and Dawadi, which shows typical characteristics of enrichment in Na+, K+, Ca2+, Cl- and depletion in HCO₃-, CO₃2-, and SO₄2-, indicating deep hydrothermal supply in Lop Nor Basin. In the ore-forming process, the Ca-Cl type brine can change the composition and crystallization route of the original ore-forming brine directly through the effect of "mixing brine", so that its mineralization degree is increased, and it is rich in K and Na. The reformed "sodium-rich" brine reacted with gypsum (CaSO₄·2H₂O), and formed glauberite (Na₂Ca(SO₄)₂·2H₂O), which existed among the porous glauberite crystals, forming super-high salinity potassium-rich brine.