中文摘要：

根据对柴达木盆地察尔汗古湖贝壳堤剖面酸不溶组分和酸溶组分的提取及其87Sr／86Sr的测定，结合沉积物中Rb／S，的变化，指出Sr同位素组成特征可有效指示源区化学风化和沉积区古环境变化；依据酸溶组分中盐度指标Sr／Ca，Sr／Ba值与Sr同位素组成曲线的对比分析，揭示酸溶组分Sr同位素可以较好的指示水体形成时的盐度。通过分析贝壳堤剖面化学风化和部分盐度变化过程，探讨了研究区晚更新世39．6-17．1kaBP（未经校正的AMS14C测年结果，全文同）湖泊高湖面的演化历史。

英文摘要：

The data for S7Sr/S6Sr, Rb/Sr and Sr contents of the acetic acid soluble components and insoluble components of shell bar section at southeastern Charhan saline lake, Qaidam Basin were presented. According to the environmental significance of Rb/Sr ratios of lake sediments, our data showed that, 87Sr/86Sr ratios can effectively indicate the catchment chemical weathering intensity and the paleoenvironmental changes of the deposit area; Cor- relation of 87Sr/86Sr with Sr/Ca and Sr/Ba ratios （salinity parameters） of the carbonate fractions indicates that the variation in carbonate 87Sr/86 Sr values can be used to reflect the salinity of the water under formation condition. Based on chemical weathering intensities and salinity variations along the sequence, the environmental change history was reconstructed between 39.6 ka BP and 17.1 ka BP for the studied area. The high lake level was maintained between 33.2 ka BP and 27.4 ka BP, both the temperature and precipitation amount were higher than those of the present day. Till about 18 ka BP, the lake started to shrink, probably suggesting that the climate turned from a warm-humid interstadial into a cold-dry glacial climate.