【摘要】 针对东海冲绳海槽地区的地震地质背景,对东海海域潜在的地震海啸进行了预研究.假设了冲绳海槽在发生8.5级大地震,断层错距高达15m的极端地震情况引发的海啸对中国东部沿海地区的影响.初步数值模拟结果表明,该地震引发的海啸的最大初始波高为4.3m,4小时左右传至浙江沿岸,近岸各处波高为1—2m,其中局部地区波高为2.4m;约7—8小时靠近上海海岸线(若震源在中冲绳海槽地区,海啸传到上海最快大约7小时),近岸波高约为1m.近岸区域地形变化复杂,海岛密布,局部地形条件可能会很大地影响实际各地点海啸波高,加上海啸在岸边爬高及港湾效应,估计波高还会升高.给出了冲绳海槽南、中、北部发生潜在地震海啸的传播等时图.笔者在东海设置了3个地震及海啸监测站,基于海啸模拟结果绘制了监测站处的海啸随时间演化曲线,分析了预研究成果对海啸预警可能发挥的作用.更多还原

【Abstract】 Supposing an M8.5 earthquake occurred in Okinawa Trough, we studied the potential earthquake-induced tsunami in East China Sea. Result of numerical simulation indicates that the initial maximum tsunami height is estimated to be 4.3 m and it takes about 4 hours to propagate to the coast of Zhejiang Province and 8 hours to reach to the shoreline of Shanghai. The max tsunami height is up to 2 m around the coast of Zhejiang Province. Based on the numerical esimulation we plot arrival time contours of the tsunami in East China Sea and time history curves on three monitoring stations. Then we discussed the significance of study in advance for tsunami early warning.更多还原