中文摘要：

通过对库姆塔格沙漠东南缘BL砂黄土剖面观测、描述和采样，分析了沉积物粒度、年代、沉积环境和地球化学元素特征，结果表明：1）BL剖面沉积物颗粒的93.34%为砂和粉砂，证明剖面为一砂黄土沉积地层；2）BL砂黄土剖面地层沉积的开始年代为全新世早期（8.3ka），是阿尔金山东部冰川消融后在特定的地形环境条件下形成的。地表沉积环境在全新世开始到8.3ka之间，受到了阿尔金山冰川和冰缘带融水的泛滥冲刷，难以形成沉积，8.3ka之后冰川积雪融水减少后在高凸的合适地形开始了连续沉积，由此形成了BL砂黄土沉积地层。BL地层沉积速率约为4.22cm/100a，早期沉积速率较快，后期则有所减缓；3）对比BL剖面沉积物特征元素比值分布模式，其与库姆塔格沙漠表层砂、内部出露地层（全新世以来）的不同沉积物特征元素比值分布模式具有极其相似的特征，证明两者的物质具有同源性，BL剖面的沉积物来源就是库姆塔格沙漠表层或者内部地层翻出来的物质。BL砂黄土沉积的过程和物源的研究为今后研究全新世以来库姆塔格沙漠区域古气候过程奠定科学的基础。

英文摘要：

Loess sediment in the margins of desert, sensitively recorded the climate changes of its source desert area. In this study, a BL section（39°24＇10.98＂N, 94°16＇00.12＂E; 2737m a.s.l.）that locates in the northern slope of the Altun Mountain and downwind direction about 25km from the edge of Kumtagh Desert, was used to reveal the environmental changes of Kumtagh Desert since the Holocene in the West China. Based on the analysis of sediment particles, geochemical element characteristics, and OSL age. Our results show：1）93.34% of the BL section sediment particles are belong to silt sand and coarse sand; 2）this sedimentary strata deposited since about 8.3ka B.P. and formed in the convex terrain environment conditions after the glaciers melting during the Early Holocene in the eastern part of the Altun Mountain. Its mean depositing rate is about 4.22cm/100a, but the rate decreased with time; 3）the loess sediment was orgined from the Kumtagh Desert including the surface material or internal exposed strata during the Holocene, because they have similar element ratio distribution patterns. Our results proved the baseline for reconstructing the detail climate changes of the Kumtagh Desert since the Holocene in the future.