不同方法求解3级地震震源机制解准确性分析  

Analysis of the Accuracy of Focal Mechanism Solutions for M3.0 Earthquakes with Different Methods

作　　者：杜航[1] 王俊[1] 江昊琳[1] 钱婷 倪昊琦 李子烨 Du Hang;Wang Jun;Jiang Haolin;Qian Ting;Ni Haoqi;Li Ziye(Jiangsu Earthquake Agency,Nanjing 210014,China)

机构地区：[1]江苏省地震局,南京210014

出　　处：《震灾防御技术》2024年第4期651-660,共10页Technology for Earthquake Disaster Prevention

基　　金：中国地震局监测、预报、科研三结合课题(3JH-202401014);江苏省地震局青年科学基金(202403);江苏省重点研发计划(BE2023082);地震科技星火项目(XH23015A)。

摘　　要：本文采用TDMT_INV、FOCMEC和CAP 3种方法对网缘、网外和网内地震震源机制解进行计算,并对3种方法所得结果进行对比分析。研究发现,TDMT_INV方法的结果稳定性高度依赖于震相准确性,但只需5个台站参与定位即可获得相对准确的震源机制解。对于网外地震,3种方法都无法反演稳定的震源机制解;对于网缘地震,CAP方法受台站分布的影响较大,使用时需谨慎。若波形质量好、信噪比高,可使用FOCMEC方法进行计算,若无清晰的P波初动可使用TDMT_INV方法进行计算;对于网内地震3种方法所得结果较为一致,但TDMT_INV方法可快速获得震源机制解。In this study,we employed the TDMT_INV,FOCMEC,and CAP methods to calculate the focal mechanism solutions for earthquakes with magnitudes greater than 3,focusing on events at the edge of the seismic network,outside the network,and within the network.We then compared the results obtained from these three methods.The stability of the TDMT_INV method is significantly affected by the accuracy of seismic phase data;however,reliable focal mechanism solutions can be achieved when at least five stations are involved in the event location.None of the methods consistently produce stable focal mechanism solutions for earthquakes occurring within the seismic network.For network-edge events,the CAP method is highly sensitive to station distribution and should be applied with caution.The FOCMEC method can be used for calculation when waveform quality is high and the signal-to-noise ratio is favorable.In cases where the P-wave onset is unclear,the TDMT_INV method is recommended.Overall,the results for intra-network earthquakes from the three methods are relatively consistent,with the TDMT_INV method providing quick focal mechanism solutions.

关 键 词：震源机制解 TDMT_INV方法 CAP方法 FOCMEC方法 

分 类 号：P31[天文地球—固体地球物理学]