中文摘要:本文通过卫片解释、水化学和Br的地球化学研究以及地质剖面结构分析，论证了达东古湖的形成、发展和消亡过程。文中指出．大约在9000年前，在柴达木盆地达布逊湖以东约200 km2的干盐滩被溶解，形成了一个卤水湖。后来由于河流改道或气候变干旱，湖水被蒸发，湖体自北向南收缩，直到千化。在湖体收缩过程中，盐类矿物按照K+ - N+ - Mg2+/Cl- - SO42- - H2O 五元体系相图所示的规律结晶。石盐析出较早，主要分布在湖的北部光卤石结晶较晚，集中分布在湖的南部。在这一过程中，钾盐发生了富集，而且富集在靠淡水源比较近的地方
Abstract:This paper makes a systematic investigation into the geomorphology, geology, Br geochemistry and hydrochemistry of intercrystalline brine of the Dadong paleolake, and, taking into account the previously obtained isotopic age data, infers the formation, evolution and disappearance of the Dadong paleolake. Some 9000 years ago, because the rivers changed their courses or the climate turned wet, there was a great increas6 in fresh water supply in the direction of the Tuanjiehu, and henoe a large amount of fresh water flowed into the salt playa from the south and dissolved an area of 200 km2 with a thickness of 1-3 m, resulting in the formation of a brine lake. As the original salt playa was composed mainly of halite containing clay, silt and carnallite, during its dissolution the silt and clay were deposited on the bottom, forming clay-bearing silt layer in the lower part of the Dadong paleolake, while the halite and carnalbte were dissolved into the water. Later, as the rivers changed their courses again or the weather turned dry once more, the amount of fresh water flowing into the playa became less and less, and the brine lake was continuously evaporated, causing the receding of the lake from north to south. Following the precipitation regularity of saline minerals shown by K+ - N+ - Mg2+/Cl- - SO42- - H2O system the Jake first precipitated halite, thus forming pure halite in the north part of the Dadong paleolake. The subsequent further evaporation of the brine and southward receding of the lake led to the gradual separation of carnallite, giving birth to carnallite layer in the south of the lake. With the unceasing evaporation, the mineralization intensity of the brine grew increasingly higher and the lake was gradually reduced in area and dried out to what it looks like at the present day. In a word, the formation and evolution of the Dadong paleolake proceeded in order of dissolution and transformation of the playa→formation of a brine lake→ evaporation, mineral separation, area. reduction and final drying out of the lake. In this process, K was concentrated with carnallite layer formed near the fresh water source.
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引用文本：
段振豪.1987.达东古湖的形成、发展与消亡[J].矿床地质,6(3):91~96.1987.The Formation, Evolution And Disappearance Of The Dadong Paleolake In The Qaidam Basin[J].Mineral Deposits6(3):91~96
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