【摘要】 综述了柴达木盆地盐湖卤水及其沉积物的硼同位素研究成果,并从pH值、离子浓度、物源补给等几方面对盐湖卤水及其沉积物的硼同位素组成进行了探讨。强烈的蒸发作用可以导致盐湖卤水的pH值降低,从而使δ¹¹B值相应地升高;卤水中的B可能会随碳酸盐的析出而进入到固相中,因此Ca²⁺浓度和Ca/Cl比值较高的湖泊,其卤水的δ¹¹B值一般都比较高;盐湖卤水及其补给水源的δ¹¹B值与B/Cl比值具有中等程度的负相关关系,这种特性也可以用来指示河水中硼的来源;当易风化的硅酸盐矿物经剥蚀迁移并最终在湖泊中沉积时,盐湖沉积物的δ¹¹B值会因这些低δ¹¹B值的物源加入而变低;此外,强烈的化学风化会使湖泊中沉积较多的细粒粘土矿物,由于粘土矿物的吸附作用也会使得盐湖沉积物中的δ¹¹B值偏低。关于柴达木盆地盐湖硼同位素的研究,不仅可以为盐湖的形成、演化及成盐成矿规律的研究提供可靠依据,而且可以为盐湖资源评价及合理开发提供科学依据。更多还原

【Abstract】 This paper reviewed the boron isotopic compositions of the salt lakes in Qaidam Basin,and the effects of pH value,material source,ion concentration on the δ¹¹B values of brines and sediments.The results showed that strong evaporation can lead to decrease pH values in the brines of salt lakes,thereby the δ¹¹B values were raised accordingly;the B in the brines may enter into the solid phase with the precipitation of the carbonate,so the salt lake with high Ca²⁺ concentrations and high Ca/Cl ratios has also generally higher δ¹¹B value in the brine.The δ¹¹B values of salt lake brines have a negative correlation with B/Cl ratios,and there is a similar phenomenon in recharge water source,which can be used to indicate the source of boron in river water.When weathered silicate minerals are eroded and finally deposited in lakes,the δ¹¹B values of salt lake sediments will be lowered due to the addition of these low δ¹¹B sources.In addition,strong chemical weathering will cause more fine clay minerals deposited in the lake,and the adsorption of clay minerals will result in the low δ¹¹B value in the sediments of the salt lake.The study on the boron isotopes of the salt lakes in Qaidam basin not only provides a reliable basis for the study of the formation,evolution and mineralization regularity of the salt lakes,but also offers a scientific basis for the evaluation and rational development of resources in salt lakes,which has important theoretical and practical significance.更多还原