末次冰期最盛时期以来中国东部边缘海潮波系统演变过程的模拟研究

MODELING OF THE TIDE WAVE SYSTEM CHANGES IN THE MARGINAL SEAS ADJACENT TO EASTERN CHINA SINCE THE LAST FULL GLACIAL PERIOD

在系统地研究了中国东部边缘海区引潮力、入射潮波、科氏力、水下地形、海岸形态及摩擦作用等因素对区域潮波系统形成影响的基础上 ,确定了中国东部边缘海的海岸轮廓是区域潮波系统形成的主导因素 ,认为模拟末次冰期最盛时期以来中国东部边缘海区潮波系统的形成过程需要 3个重要的控制性条件 ,即入射潮波、海岸线变迁过程和海面变化曲线。利用中国东部边缘海潮波系统与海岸演变模拟支持系统 ,对末次冰期最盛时期以来 30个时期中国东部边缘海区潮波系统的形成与演变过程进行了模拟再现研究 ,系统地恢复了在不同的海面高程、不同的岸线形态条件下全日潮、半日潮潮汐分布特征。模拟结果显示 ,末次冰期最盛时期以来 ,12 40 0 a B.P.和 75 0 0 a B.P.两个时间界限分别代表了旋转潮波系统—无潮点开始出现、中国东部边缘海潮波系统现代格局基本奠定这两个特征事件的发生时间 ,将中国东部边缘海潮波系统的演变过程划分为 3个发展时期。

Based on systematic analysis of the effect of some factors associated with the marginal seas adjacent to eastern China(i.e.the Bohai Sea,Yellow Sea and East China Sea),such as the Coliolis acceleration,tidal amplitude and phase on the outer boundary,seabed topography,coastline configuration,and frictional coefficient on the formation of the regional tide wave system,the authors summarize that the coastline configuration in the marginal seas is the most important factor in the regional tide wave system formation.The modeling reconstruction of the tidal wave system change needs three essential conditions:tide amplitude and phase on the outer boundary,coastline change and sea level fluctuation processes.Using the modeling support system for marine dynamics and coast changes,the authors systematically simulate and reconstruct the diurnal and semi diurnal tide change processes in 30 periods since the Last Full Glacial Period with the different places of coastline and the different heights of sea level.The results indicate that 12 400 aB.P. and 7 500aB.P. separate the time since the Last Full Glacial Period into three periods.At about 12 400a B.P.the rotational tidal system has come into being.At about 7 500aB.P. the modern tide wave system has established in the marginal seas adjacent to eastern China.