我国某些盐湖粘土化学成分的初步研究

A PRELIMINARY STUDY OF THE CHEMICAL COMPOSITION OF CLAY SEDIMENTS FROM SOME SALT LAKES OF CHINA

本文总结了我国盐湖粘土化学成分一般特征,以及不同地区盐湖和盐湖不同沉积阶段粘土化学成分特征。讨论了控制盐湖粘土化学成分的主要因素。提出了利用盐湖粘土中Al_2O_3/MgO比值来反映盐湖沉积过程中某些环境变化。

This study shows that the chemical composition of clay from some salt lakes of China is similar to that of illite clay and possessed of the compositional features of salt clay and continental clay distributed in frigid-temperate zones. Clay samples from the salt lakes of Xizang (Tibet are relatively rich in MgO, those from Qinghai are comparatively abundant in K2O, and those from Nei Mongol are relatively rich in Al2O3. Clay in the salt lakes at the non-salt-forming stage is comparatively abundant in K2O, while that in the salt lakes at the salt-forming stage is relatively rich in MgO. The chemical composition of clay in the salt lakes is controlled mainly by clay mineralogy, the chemistry of brines and climate. It is suggested that the ratio of Al2O3/MgO in clay samples from the salt lakes can reflect the alternation of relatively fresh-water and comparatively saline-water stages, or that of relatively dry and wet climates during the processes of sedimentation in the salt lakes.