2019年6月16日新西兰克马德克群岛M_(W)7.3地震震源机制快速反演与海啸波高数值模拟

The rapid focal mechanism solution and tsunami numerical simulation of the M_(W)7.3 earthquake occurred near Kermadec Islands in June 16,2019

利用全球虚拟地震台网的波形数据,采用W震相快速震源机制反演方法,得到2019年6月16日新西兰克马德克群岛附近海域M_(W)7.3地震信息。节面Ⅰ:走向角186°/倾角37°/滑动角71°,节面Ⅱ:走向角29°/倾角55°/滑动角104°,矩震级M_(W)7.26。震源机制结果表明,此次地震是一次逆冲性质为主的浅源板间地震事件。由反演得到的震源机制断层面几何参数,采用COMCOT模型进行了海啸数值模拟计算,模拟结果表明,本次地震发生后,在震源附近产生了轻微海啸波动,最大波幅约为0.28 m,在拉乌尔岛船湾潮位站附近的波幅约为0.05 m,与实际观测值0.09m接近。

An earthquake with a magnitude of M_(W)7.3 occurred near the Kermadec Islands,New Zealand in June 16,2019.Based on the waveform from the Global seismograph Network,the focal mechanism of the earthquake is calculated rapidly using the W-phase method.For the nodal planeⅠ,strike is 186°,dip is 37°,rake is 71°,For the nodal planeⅡ,strike is 29°,dip is 55°,rake is 104°with the moment magnitude M_(W) of 7.26.The focal mechanism solution shows that the earthquake with thrust-faulting occurred at the shallow boundary between the Pacific Plate and Indian-Australian Plate.Tsunami numerical simulation is implemented with COMCOT model using the actual fault plane solution from W-phase inversion.The simulation results show that the maximum waveform height is about 0.28 m.The maximum numerical simulation height near the Raoul Island is about 0.05 m,which is close to 0.09 m recorded by the gauge station.