通过对库姆塔格沙漠东部的沙漠、戈壁、绿洲、湿地、干河床等地貌单元地表沉积物化学元素的分析，研究了不同类型沉积物常量、微量元素的UCC标准值、Ba-Sr含量比值、化学蚀变指数等特征。结果表明：各类型沉积物的元素特征差异显著，但都处于低等风化阶段。库姆塔格沙漠东北端的平沙地、灌丛沙地与北侧戈壁地表沉积物元素特征相近，物源是北山；沙漠东缘沙物质有相近的主元素含量和Ba-Sr含量比值，化学风化特征和Fe、Mg含量自北向南呈现渐变趋势，表明受到偏北风的搬运混合作用，其可能的物源包括南部阿尔金山洪冲积物、东侧的干河床和戈壁。沙漠与敦煌绿洲间的戈壁地带化学风化微弱，区域差异不明显，但不同部位沙物质的元素含量有近源性。鸣沙山西侧的沙物质元素不同于库姆塔格沙漠，而与之相近的党河漫滩相近，因此其最有可能的物源是党河。
A geochemical study was conducted on the sediments from the east Kumtagh Desert and its nearby geomorphic units, including desert, gobi, oasis, wetland, wadi, et al. The contents of major and trace elements were compared with the upper continental crust's average value (UCC), and the Ba-Sr ratio and chemical index of alteration (CIA) of each sample were analyzed. Preliminary results show a weak weathering level for all the samples, despite the significant differences among the sediments from different environments. The sediments from sandy land and vegetated land at the northeast corner of the Kumtagh Desert share similar geochemical features, indicating a same source-area of the North Mountain. Sands at the east of the desert have similar element components and Ba-Sr ratio and the chemical characteristics change gradually from north to south, indicating an aeolian mixture effect by the north winds. Potential sources of the desert sands include the alluvial deposits from the south Altyn Tagh Mountain, the gobi area to the east, and the wadis. The gobi area between the desert and the Dunhuang Oasis suffers from weak weathering, whereas chemical features of sediments at various locations are similar to their nearby potential source areas. Sand elements at the west Mingsha Megadune differ from the Kumtagn Desert clearly but are alike to the deposits in the Danghe River, thus the Danghe River is the most likely provenance of the Mingsha Megadune.
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