河北昌黎黄金海岸横向沙脊表面的粒度分布模式  

Distribution model of grain size on transverse ridge at Changli Golden Coast in Hebei Province

作　　者：董玉祥[1] 马骏[1] 黄德全[1] 

机构地区：[1]中山大学地理科学与规划学院,广州510275

出　　处：《地理研究》2008年第4期725-733,共9页Geographical Research

基　　金：国家自然科学基金项目资助(项目编号:40571019)

摘　　要：河北昌黎黄金海岸自然保护区内的横向沙脊规模高大、形态典型,对其表面采集的47个沙丘表面沉积物粒度样品的分析结果,该海岸横向沙脊表面粒度总体上是中砂、分选好、对称和中等峰态,但脊顶、坡部及坡脚的粒度分异明显,自沙脊两侧坡脚向脊顶粒径变细、分选变好,向陆背风坡的细化与分选优于向海迎风坡,脊顶粒径最细,向陆背风坡脚最粗,是一种新型的沙丘表面粒度分布模式。该粒度分布模式是该区域主风向与强风向交替变化及其风速差异、沙脊高大且两侧不对称等组合作用的结果。A total of 47 samples were collected on typical coastal transverse ridge at Changli Golden Coast in Hebei Province, which is one of the most typical coastal aeolian distribution regions in China and is famous for the tall and typical coastal transverse ridges. The parameters of grain size of the 47 samples were analysed and calculated by use of the number of mean size, standard deviation, skewness and kurtosis. The results showed that, as for the deposits on the surface of transverse ridges in Changli Golden Coast, under the same depositional environment the particle size at windward slope base, windward slope, dune crest, leeward slope and leeward slope base as a whole belonged to the medium sand with better sorting, approximately symmetric skewness and moderate kurtosis. Some differences existed in the particle-size parameter value at different sites, especially the mean particle size at different sites of the transverse ridges surface greatly, i. e. , the particle size became finer and the sorting became much better from windward slope base and leeward slope base to the crest of transverse ridges, particle size at leeward slope was relatively finer than at the windward slope, the sorting at leeward slope also better than at the windward slope. As for the whole dune surface, the particle size was the coarsest at lee- ward slope base and the finest at the crest of transverse ridges. The distribution characteristics of grain size on coastal transverse ridge could be concluded as the finest and the best sorting sands distributed on the crest of coastal transverse ridge and the coarsest sands distributed at the leeward slope base, which is a new distribution model of grain size on dunes. The surface particle-size distribution model of the transverse ridge in Changli Golden Coast resulted from the combined effects of the alternation variation of the region＇s prevailing wind direction and strong wind direction and wind force difference as well as asymmetry on both sides of the dune. In which, the large height and

关 键 词：海岸 横向沙脊 粒度分异 河北昌黎 

分 类 号：P931.3[天文地球—自然地理学]