孔隙介质地震电磁信号的数值模拟研究

本文利用最近开发的孔隙介质震电波场算法开展了数值模拟研究,重点探讨不同结构模型中双力偶点源以及有限断层面源作用下产生的地震波及其伴随的电磁信号的时域和频域特征,考察了不同震源时间函数类型对震电波场数值模拟结果的影响,并以Ricker子波为例讨论了震电波场的频率响应特征.结果表明:地震电磁信号的波形、振幅和持续时间等都不同程度受到模型结构的影响,结构越复杂,波形也越复杂;不同震源(双力偶点源与有限断层面源、震源时间函数类型、Ricker子波峰值频率)产生的位移场和电磁场在波形和频谱响应方面整体上呈现相似的特征,但在波形和频谱的幅度和复杂程度方面存在一定差异.

Numerical simulation study of co-seismic electromagnetic signals in porous media

Based on the recently developed numerical method, we simulated the co-seismic electromagnetic (EM) signals in porous media. We focused on the characteristics of the co-seismic EM signals generated by a double couple point source or a finite fault planar source in the models with different structures. The effects of source time function type and peak frequency also have been investigated. The simulation results show that the waveform, amplitude and duration time of seismic-EM signals depend somehow on the model structures; the seismic waves and EM signals for different source models (a double couple point source or a finite fault planar source, source time functions, peak frequencies) also show similar characteristics in both time and frequency domains, although there are some differences for the amplitude and complexity of waveform and frequency response.