在大地震发生后,快速准确地获得地震震源信息对应急救援十分重要,但是现有技术方法往往难以在快速准确地获取地震震源机制的同时获得破裂空间的分布特征。文章在传统W-phase反演技术的基础上开发了多点源W-phase反演方法,实现对大震破裂空间尺度上能量释放特征及震源机制的快速测定,并以2004年苏门答腊MW 9.1大地震为例,测试程序的有效性。研究中设置了1、2、3、4、5、6个点源来分别测定此次地震的能量释放特征及震源机制。结果显示,震源机制随着空间位置由南向北的变化与俯冲面走向变化一致,与设定点源附近的历史地震震源机制高度吻合。因此,基于多点源的W phase快速反投影技术将能更好获得大震空间能量释放特征,为震后应急及海啸预警提供科学支持。
btaining earthquake source information quickly and accurately soon after the occurrence of a large earthquake is very important. However, it is often challenging to simultaneously obtain the distribution characteristics of rupture space. In this paper, a multiple point source based W-phase inversion method was developed based on the traditional W-phase inversion technology. The new method can quickly determine the energy release characteristics and focal mechanism of a large earthquake rupture on the spatial scale. The effectiveness of the program was tested by taking the 2004 Sumatra MW9.1 earthquake as an example. We set up 1, 2, 3, 4, 5, and 6 point sources to determine the energy release characteristics and focal mechanism of the earthquake. Results show that the change of focal mechanism from south to north is consistent with the striking change of the subduction surface, which is also highly consistent with the focal mechanisms of historical earthquakes near the point sources. Therefore, the multiple point source based W-phase inversion method can effectively result in spatial energy release characteristics of large earthquakes, thus providing scientific support for post earthquake emergency response and tsunami warning.
彭宇洋,王墩.基于多点源的W-phase反演及其在2004年 苏门答腊MW9.1大地震中的应用[J].地震工程学报,2023,(1):169-180. PENG Yuyang, WANG Dun. Multiple point source based W-phase inversion and its application to the Sumatra MW9.1 earthquake in 2004[J]. China Earthquake Engineering Journal,2023,(1):169-180.复制