摘要
利用剪切位错点源作为震源模型,采用横向均匀的水平层状介质模型作为地壳近似模型,使用F-K波数积分法计算格林函数并拟合理论地震图。在已有理论方法的基础上,利用国家数字地震台网所记录的宽频带数字资料,选取了2002~2003年间发生在国内MS≥5.4的5个地震事件进行震源机制解测定。并且,将测定结果与HRV的矩心矩张量解、USGS的地震矩张量解、中国地震信息网的速报震源机制解分别进行了对比,通过实际计算表明测定结果是可靠的。从而初步验证了在中国国家数字地震台网中使用F-K波数积分法测定震源机制解的可行性和准确性。
In this paper, we use simple point source model—shear dislocation model and approximately regard the earth crust as horizontally layered medium that is transverse homogeneous. We use F-K (frequency-wave number) integral algorithm to compute Greens′ function and synthesize the theoretical seismograms. Based on the existing theory and methods, we use broadband data of five seismic events of scaled MS≥5.4 and occurred from 2000 to 2003, to determine the focal mechanism, then compare these results with CMT of HRV, seismic moment tensor solution of USGS, source parameters of China Seismic Information, respectively. The result shows us the usability and veracity of these theories and methods.
引文
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