Inverting seismograms of weak events for empirical Green's tensor derivatives
Inverting seismograms of weak events for empirical Green's tensor derivatives
复制标题
弱事件地震图反演以获得经验格林张量导数
DOI：
10.1046/j.1365-246x.1998.00513.x
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发表时间：
1998
影响因子：
2.8
通讯作者：
J. Zahradník
中科院分区：
文献类型：
--
作者：
V. Plicka;J. Zahradník
给定一个台站和一组已知震源机制的聚集弱事件记录，可以计算经验格林张量空间导数（EGTD），几乎不需要源eVects。该反演方法在频域上解决了一个超定的线性代数方程组，而FFT提供了时间历史。它们代表了台站和整个震源区之间路径的最小二乘平均表示，包括多个P相和S相，尾波等。该方法可用于模拟震源机制与所采用的弱地震大相径庭的地震。本文用变震源机制的合成地震记录和地震群记录证明了这一点。期望EGTD方法可以改善强运动合成和源反演。
SUMMARY Given a station and a suite of clustered weak event records whose focal mechanisms are known, empirical Green’s tensor spatial derivatives (EGTD) can be calculated, almost free of the source eVects. The inversion method solves an overdetermined system of linear algebraic equations in the frequency domain, and a FFT provides the time histories. They represent a least-squares averaged representation of the path between the station and the entire focal zone, including multiple P and S phases, coda waves, etc. The method can be used for modelling earthquakes whose focal mechanisms are quite diVerent from the weak events employed. This is proved here using both synthetic seismograms and earthquake swarm records with variable focal mechanisms. It is expected that the EGTD method can improve strong motion syntheses and source inversions.