琼州海峡东口底形平衡域谱分析  

Equilibrium range spectra analysis of nearshore bedforms in the East Qiongzhou Strait

作　　者：程和琴[1] 胡红兵[1] 蒋智勇[1] 王宝灿[1] 

机构地区：[1]华东师范大学河口海岸国家重点实验室,上海200062

出　　处：《海洋工程》2003年第4期97-103,共7页The Ocean Engineering

基　　金：国家自然科学基金面上资助项目(49571007);上海市科委青年科技启明星计划资助项目(97QA1406);上海市教育发展基金曙光计划资助项目(99SG13)

摘　　要：1993年用GPY浅地层剖面仪对琼州海峡东口中水道两个水深18～40m的浅段进行网格状探测,通过对探测记录的平衡域谱分析近似计算底形运动速率。探测、分析和计算结果表明:分布在深处的大型不对称沙波平均波长416m、平均波高8 8m,平均运动速率0.92cm h;分布在浅处的小型对称、不对称沙波平均波长144m、平均波高4.9m,平均运动速率5 13cm h。虽然这些底形运动速率大于用经验公式和其它理论公式的计算值,却接近于近年来的原位观测值和相似尺度底形风洞实验值,所以平衡域谱分析是一种相对简便准确的小尺度底形稳定性评估方法。Bedforms generated by currents and waves on a sandy bottom are of practical importance to near bottom flow, wave attenuation and sediment transport. The bed configurations were detected with a Shallow Seismic Profiler GPY in 1993 in the east entrance of the Qiongzhou Strait, South China Sea. Direct measurements were made within two study areas at depths between 18 m and 40 m. The measured records are analyzed with spatial and temporal equilibriumrange spectra. The results reveal the presence of asymmetric largescale sand dunes, and symmetric and asymmetric small-scale sand dunes composed of fine and medium sands. The largerscale dunes have an average spacing of 416m,a height of 8.8 m and a celerity of 0.92 cm/h. The smaller-scale dunes have an average spacing of 144 m,a height of 4.9 m and a celerity of 5.13 cm/h. The migration rates estimated in the present paper are much larger than those with theoretical and empirical flume data, while they are close to the field and wind tunnel data in a similar grain size. To sum up, the equilibrium spectra analysis can be potentially applied to the temporal stability evaluation of nearshore bedform. 

关 键 词：琼州海峡 底形 稳定性 平衡域谱分析 运动速率 

分 类 号：TV148[水利工程—水力学及河流动力学]