南海北部海底沉积物临界起动流速空间分布特征分析

Analysis of spatial distribution characteristics of seabed sediments critical starting velocity in the northern South China Sea

为研究南海北部海底沉积物临界起动流速空间分布特征,通过自测和资料收集得到45个站位沉积物物性资料,根据沉积物类型选用适合的方法计算临界起动流速,并评判计算结果的适用性,结合沉积物空间分布规律和统计结果插值,共得到112个站位数据,绘制成沉积物临界起动流速空间分布图。研究结果显示南海北部沉积物临界起动流速存在空间差异性,其分布特征与沉积物粒径分布规律基本对应并受其控制。与南海上层流场进行对比分析,得到冬夏两季陆架区沉积物起动难易程度分布图,为研究海洋动力对南海北部海底沉积物改造机制及海底沉积演变规律提供依据。

To study the space distribution characteristics of critical starting velocity of sediments in the northern South China Sea（SCS）,the 45 stances sediment physical property data of corresponding area has been collected and self-test,then calculating the critical starting velocity by choosing appropriate formula and evaluating the applicability of the results. According to the sediment space distribution and statistical results,112 stances sediment critical starting velocity values have been received by interpolation and drawn. The results show that sediments critical starting velocity is different in the space. The distribution of sediment particle size corresponds with distribution characteristics of critical starting velocity substantially and controls it. Compared with upper laminar flow field in the northern SCS,the degree of starting difficulty of the seabed sediments continental shelf in the winter and summer has been gained,which provides the basis to study the transformation mechanism of seabed sediment by ocean dynamics and change rule of seabed sediment in the northern SCS.