摘要
由腾格里沙漠东南缘沙坡头附近新月形沙丘表面沉积物的系统采集分析结果 ,发现从北部沙漠主体向黄河南岸 ,沙丘沙平均粒径变细但分选变差。同时 ,粒径及分选性在沙丘断面出现两种变化模式 ,其一是沙漠主体新月形沙丘由两侧坡部向丘顶区域粒径变细分选变好 ;其二为黄河两岸阶地和湖盆滩地的新月形沙丘丘顶沙粒粗于其它部位但分选仍然最好。根据粒度参数间的相互关系和其它环境条件的分析 。
The 69 sand samples were collected and analysed from crescentic dunes developed on different geomorphological sub-environment such as banks of Yellow River and ma in part of southeastern Tengger Desert in the vicinity of Shapotou District, Nin gxia. The results show grain size and sorting parameters varies systematically w ith not only position of the dunes but also geomorphologic location of these dun es. The mean grain size decreases and standard deviation increases from the main part of the desert to the southern terrace of Yellow River. It was also found t hat two-distinct patterns of grain size variation across a dune profile as well as other types of dune such as linear dunes in other desert. The first is that crestal zones of the dunes in the main part of Tengger Desert composes of finer and better sorted than both windward and lee flanks. The second, the crest sand is coarser but still better sorted than any other position of dunes in the banks of the Yellow River. According to analysis of the interrelation between grain s ize parameters and other environmental conditions, the mechanics of grain size v ariation and some skewness characteristics of dune sands have been discussed in this paper.
出处
《中国沙漠》
CSCD
北大核心
2001年第3期271-275,共5页
Journal of Desert Research
基金
国家自然科学基金 (40 0 710 12 )
沙坡头开放站基金资助
