国内外海岸风成砂粒度参数特征的比较与分析

The Comparison and Analysis of Grain Size Parameters of Coastal Aeolian Sands in China and Abroad

利用 2 78个国外海岸沙丘砂样数据和 136个国内海岸沙丘砂样数据 ,采用平均粒径、标准偏差、偏度和峰态等指标 ,对国内外海岸风成砂的粒度参数特征进行了比较和分析。结果表明 ,我国温带海岸风成砂的粒度参数特征并不完全具备是由分选很好的细砂组成、偏度为对称至正偏、峰态很宽等国外海岸风成砂的粒度参数特征 ,此与我国海岸风成砂特有的发育条件和演化过程密切相关 ,其中主要与季风气候特征显著、形成时间短风力作用时间有限以及风沙活动空间狭小等有关。

The characteristics of grain size parameters of coastal aeolian sands are studied based on 136 grain size samples collected in China and 278 samples collected abroad. The results different from previous results show the coastal aeolian sands are not all composed of fine sands with high sorting degree. Most are positively skewed. Compared with coastal dune sands in other countries, coastal dune sands in China are characterized by coarser, higher standard deviation, more negative skewness and sharper kurtosis. These characteristics of coastal dune sands are connected with the special physical conditions in China and evolution processes. The formation mechanisms include the significant monsoon climate, short forming time and as narrow space for aeolian activities.