Evolution of Jilantai Salt Lake in the last 13.8 ka was reconstructed based on the analysis of evaporate minerals, carbonate minerals and detrital minerals from the core JLT-20I0. The lake water was fresh or slightly salty between 13.8 and 11.7 cal ka BP. The lake began to shrink between 11.7 and 10.2 cal ka BP, and then it entered into the lagoon stage. Sulfate deposition occurred in Jilantai Salt Lake between 10.2 and 5.5 cal ka BP, meanwhile, from 9.0 to 8.2 cal ka BP there existed a significant desalination process. The lake reached full chloride deposition stage between 3.7 and 2.0 cal ka BP, and a short and obvious desalt period occurred between 2.0 and 1.7 cal ka BP. Overall, evaporate minerals appeared just at the beginning of the Holocene when temperature increased relative to the late glacial. As the regional arid climate continually affecting the area, Jilantai Salt Lake gradually shrank and salinized.%通过系统分析吉兰泰盐湖JLT-2010孔蒸发盐类矿物、碳酸盐矿物、碎屑岩矿物等,结合AMS14C测年获得的年代序列,研究该湖13.8 ka以来的演化过程.结果表明:吉兰泰盐湖13.8-11.7 calka BP期间水体较淡；11.7-10.2 calkaBP期间湖泊开始萎缩、咸化,进入咸水湖阶段；10.2-5.5 cal ka BP期间湖泊进入硫酸盐沉积阶段,其中9.0-8.2 cal kaBP经历了一个明显的淡化过程；5.5 cal ka BP以来,湖泊成盐作用进一步加强,由前期的硫酸盐沉积转变为氯化物沉积,其中3.7-2.0 cal ka BP达到全面氯化物沉积阶段,2.0- 1.7 cal ka BP又经历了一个短暂而明显的淡化过程；目前,该盐湖已进入干盐湖发展阶段.总体而言,吉兰泰盐湖蒸发盐类矿物主要是在全新世增温的背景条件下逐步萎缩形成的,由于区域性干旱气候的持续影响,吉兰泰盐湖逐步萎缩、咸化,进而析盐.
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