摘要
定边盐湖区共有14个硫酸盐型盐湖。固体盐矿主要产于苟池和花马池,上部为石盐层,下部为芒硝和白钠镁矾层,其^(14)C年龄距今14700～12400a间。液体矿分布广,包括湖表卤水、晶间卤水和孔隙卤水,其蒸发析盐过程服从Na^+·Mg^(2+)∥Cl^-·SO_4^(2-)—H_2O四元体系相图所指示的规律。湖盆多彼此孤立不相连,为河流侵蚀和风蚀成因。盐分主要来源于白垩纪地层和周边盐渍地。
There are 14 saline lakes in the Dingbian saline lake areas. Salt deposits mainly occurred inside the Gou Chi and Huama Chi ponds. The upper part of the deposits is halite layer, and the lower part is mirabilite and astrakhanite. 14C age of the puddly soil. of the superface and floor of salt beds is 12400±240a and 14700±360 a, separately. Apart from that, there are the modern saline deposits exsisting commonly inside the surface of each lake. The hydrochemical type of brine from each lake belongs to the sulphate type. Its process of concentration and evaporation accords with the principles indicated by the phase diagram of the Quaternary system Mg+·Na+//Cl- ·SO42+-H2O.
The lake basin was growing up out of the trough valley of the rock beds. It was formed by stream and wind erosion. The salinity in the saline lakes mainly originated from the Cretaceous period stratum and the saltlick around.
关键词
盐湖
地质特征
成因
水化学
类型
saline lake, hydrochemical type, sulphate type, Dingbian, Shaanxi
