敦煌月牙泉景区沙丘粒度特征

 对月牙泉外围沙山表面沉积物进行系统采样，结合区域风况，分析了沙山典型部位的粒度分布及其参数特征。月牙泉北侧金字塔沙丘沙粒较粗，分选性较差，正偏趋势显著；月牙泉南侧线形沙丘以细沙为主，分选性较好，分布属正偏态。北侧金字塔沙丘从西南和西北两个坡面到东侧坡面，粗颗粒减少、分选性变好，但趋势不明显，说明金字塔沙丘未发生明显移动；而南侧线形沙丘自南侧坡面向北侧坡面沙粒粒径变小、分选变好，较细的沙粒被搬运并沉积北侧坡面，搬运作用十分明显，即线形沙丘向月牙泉方向发生明显移动。通过粒度分析风沙动力环境表明，月牙泉风沙危害主要来自南侧沙山北移。

Grain Size Characteristics of Sand Dunes around the Crescent Moon Spring in Dunhuang,China

Through systematic sampling of the sand dunes around the Crescent Moon Spring, combined with regional wind conditions data, this paper made an analysis of the particle size distribution and grain size characteristics. The pyramid dune to the north of the Crescent Moon Spring's particle size is relatively coarse and sorting is poor, with a distribution of more positive skewness, while the liner sand dune to the south of the Crescent Moon Spring mainly consists of fine sand and better sorting, with a distribution of positive skewness. From the northwest and southwest slopes to the east slope, sediment grains becomes finer, and sorting becomes better, but the trend is not significant, indicating that there is no significant movement of the pyramid dune. However, on the liner sand dune, from the southern slope to the north slope, sand particle size becomes finer and sorting changes better, showing that the movement of linear sand dune to south of the Crescent Moon Spring is obvious. Analysis of wind power environment and the grain size characteristics indicates that the blown sand disaster to the Crescent Moon Spring mainly comes from the northward movement of the linear sand dune movement.