福建长乐海岸-海滩沙丘系统砂物质的粒度特征反映的海岸动力环境分异

Grain Size Characteristics Reflecting Coastal Dynamic Environment of Sand Material in the Coast Beach-Dune System,Changle,Fujian

通过对福建长乐东部海岸典型的海滩-沙丘系统表层砂样的粒度分析，探索海滩砂与沙丘砂物质物源及其在海滩与滨海沙丘之间输移变化的关系模式。结果表明：1）长乐海岸横向沙丘表面粒度组成以中砂和细砂为主，平均粒径介于1．53~2．31Ф，平均值为1．98Ф；海滩砂的粒度组成以粗砂、中砂和细砂为主，平均粒径介于1．26~2．08Ф，平均值为1．76Ф；海滩砂分选性不如沙丘砂。2）海滩-沙丘系统的砂质沉积以滚动和悬浮组分（ OP）、悬浮和滚动（ PQ）为主，同时含有极少量的递变悬浮组分（ OR），反映了典型的海陆过渡相（潮间带和潮上带）的沉积环境，经常遭受风力和波浪的混合作用。3）从粒度特征看，研究区海滩-沙丘系统的动力关系属于完全耗散性，海岸系统的动力环境，即波浪、潮汐、风力的共同作用，以及海滩宽度与坡度、海滩与沙丘之间的相互作用关系决定了海滩-沙丘系统的粒度组成和粒度参数特点。

Through surface sand particle size analysis of three typical beach-dune systems in the eastern＆nbsp;coast in Changle, Fujian, we explored sand material source of beach and coastal dune, in order to find out the change of transport pattern and relationships between beach and coastal dunes. Results shown that：（1） the main sand of transverse dune in the coast is medium and thin sand, with average particle size in the range of 1. 53~2. 31Ф, and average value is 1. 98Ф; beach sand particle size composition is domina-ted by coarse sand, medium sand and thin sand, average particle size is between 1. 26~2. 08Ф, and av-erage value is 1. 76Ф, beach sand size was more relatively coarse sorted;（2） Beach-dune system sandy sediments is mainly rolling and suspension components （OP）, suspension and rolling components （PQ）, and contained a small number of graded suspension （ OR） , reflecting the typical marine-continental transi-tional facies sedimentary environment dominated by wind and wave hybrid power;（3） beach-dune system are complete dissipation, beach width and slope, beach sedimentary, and the interaction between beach-dune system determine the granularity composition and characteristic parameters.