察尔汗盐湖的河流改道、湖泊迁移与钾盐富集

MIGRATION OF RIVERS AND LAKES IN THE QARHAN SALT PLAYA,QAIDAM BASIN

目前察尔汗盐湖正处在干盐湖早期阶段,即干盐滩与卤水湖并存的阶段。在它的周缘分布有10个大小不一的湖泊,除了东陵湖以外,各湖均依靠内陆河的补给来维持其生命,各湖的大小与汇水河的流量基本成正比。由于察尔汗的内陆河经常改变自己的河道,从而造成了湖泊的迁移,也使钾发生了富集。本文通过对比50年代和80年代,察尔汗地区的河湖分布情况,结合古湖、古河道和达布逊湖、达东古湖水化学的研究,证明河湖迁移的情况,并阐明与河湖迁移有关的钾盐富集机理。

There are 10 brine lakes surrounding the Qarhan Salt Playa, each maintaining its own life on the fresh water supply of inland rivers. Because of neotectonic movements or blocking by river sediments and the influence of the rotation of the earth, the rivers often change their courses, leading to the migration of brine lakes. For example, the formation and vanishing of the ancient Dadong Lake, the formation of the new Daxi Lake and the decrease of the volume of water in Dabsan Lake were the results of the migration of the lakes due to the diversion of the rivers.The migration of lakes accompanied by the diversion of river courses is favourable for the enrichment of potassium. There are two different mechanisms for the concentration of potassium: (1) the dissolution of playa and redeposition of the salt minerals, which gathered potassium from the completely dissolved playa: (2) selective dissolution of carnallite and other forms of potassium from playa around brine lakes and then concentration of the potassium.