一种叠前地震资料单频噪声压制新方法

A New Method of Single Frequency Noise Suppression in Prestack Seismic Data

针对常规陷波处理方法去除单频噪声时会"完全扼杀"相同频率有效波的缺陷,提出了一种基于独立分量分析(ICA)的叠前地震资料单频噪声压制新方法。该方法将叠前地震资料的多道观测记录按照统计独立的原则,首先利用非零时间滞后协方差,运用两步特征值分解法(EVD)成功地去除部分加性噪声的影响;再利用ICA算法更好地分离出单频噪声源信号。改进的ICA算法能够有效地克服加性噪声对常规ICA算法的影响,较好地分离出叠前地震资料中的单频噪声源信号,实现独立分量分析对叠前地震资料单频噪声压制的目的,更加有效地保护相同频段范围的有效波,从而提高叠前地震资料的信噪比。通过仿真试验和实际地震资料处理表明,该方法应用效果较好,能够更加满足实际生产的需要。

In consideration of the defects of'completely avoiding'similar frequency in single frequency noise removal in routine notch processing,a new method based on independent component analysis(ICA)was proposed for suppressing single frequency noise in prestack seismic data.In accordance with the principle of statistic independence for multiple prestack seismic observation data,non-zero time lag′s covariance was used firstly in the method,and the impact of partial additional noise was successfully removed by using approach of two-step eigenvalue decomposition(EVD),and the source signal of single frequency noise was better separated with ICA algorithm.The improved ICA algorithm could be used to effectively overcome the impact of additional noise on conventional ICA algorithm for better separating the source signal of single frequency noise from the prestack seismic data,for suppressing the single frequency noise in prestack seismic data with independent component analysis,thus the effective wave having the same band range of noise could be better protected for improving the SNR of the prestack seismic data.The simulation experiment and actual seismic data processing show that the method has good effect of application,and it can better meet the needs of actual production.