提高微地震资料信噪比的频率域极化滤波

Polarization filtering in frequency domain for improving the S/N of microseimic data

微地震资料信噪比低、波场复杂,利用常规极化滤波难以取得比较理想的效果。在时间域与频率域极化滤波方法的基础上,针对利用傅里叶变换的频率域极化滤波存在频谱泄漏等问题,引入多阶窗函数,消除了常规方法构造谱密度矩阵中奇异值的影响,同时考虑多道信号的空间连续性对频率域滤波方法进行改进。模型和实际资料处理的结果表明,该方法能有效提高微地震资料的信噪比。

Microseismic data is characterized by low S/N and complex wavefield,and conventional polarization filtering cannot achieve ideal results.In order to solve the spectral leakage problem existing in the polarization filtering in frequency domain by using FFT,on basis of polarization filtering in frequency domain and time domain, multi-order window function was introduced,which eliminated the impact of singular value of spectral density matrix constructed by conventional method.Meanwhile,the filtering method in frequency domain was improved by considering the spatial continuity of multitrace signals.Modeling testing and actual data processing results indicate that the method can obtain relatively effectively improve the S/N of microseismic data.