基于波动方程地震数据映射的随机噪声去除方法研究  

The method of random noise elimination based on wave-equation seismic data mapping

作　　者：李志晔 李振春[1] 刘玉金 张凯[1] 

机构地区：[1]中国石油大学(华东)地球科学与技术学院,青岛266580

出　　处：《地球物理学进展》2015年第4期1743-1749,共7页Progress in Geophysics

基　　金：国家自然科学基金(41204086);国家高技术研究发展计划(863)(2011AA060301);CNPC物探重点实验室华东研究室联合资助

摘　　要：一般的随机噪声去除方法都是通过信号分析和处理手段在信号变换空间对随机噪声进行压制,这些方法没有考虑地震信号本身所具有的特性,容易造成有效信号的损失,而本文的随机噪声去除方法是从地震波传播的角度,利用地震数据映射方法根据有效信号和随机干扰在成像空间和数据空间的不同表现进行相干加强处理去除随机干扰,可以在去除噪声的同时更好的保持有效信号.数据映射算子由频率波数域共偏移距相移法叠前时间偏移和反偏移算子两部分构成.在常规叠前时间域相移法的基础上,本文采用成像域相移法进行叠前时间偏移和反偏移,可以在一定程度上提高数据映射的计算效率,并采用自适应的变孔径方法来改善数据映射的成像质量.通过模型和实际资料处理表明,该去噪方法能有效提高资料的信噪比,改善同相轴的连续性.The general de-noising approaches are applied in the transformed domain using the signal analysis and processing method to eliminate random noise.These methods take seismic wave as ordinary signal,which leads to loss useful signal easily.But the data mapping de-noising method in this article is based on the difference between the effective signal and the interference signal in the wave domain from the perspective of seismic wave propagation by means of the migration and demigration in the imaging domain and data domain to get rid of the random disturbance with the coherent enhancement processing,which can eliminate noise and preserve effective signal simultaneously. The method includes two parts,common offset phase shift pre-stack time migration and demigration operator in F-K domain.Based on the phase shift in conventional pre-stack time domain,we propose the phase shift method in the image domain which could visibly improve the computational efficiency of the migration and demigration.In this paper,the principle of phase shift method in imaging domain is discussed in detail. Moreover,adaptive variable aperture calculation formula is used to improve the quality of data mapping.After processing the models and real data,we can draw the conclusion that the de-noising method can effectively increase signal to noise ratio of seismic data and improve the continuity of events.

关 键 词：相移 偏移 反偏移 变孔径 相干加强 去噪 

分 类 号：P631[天文地球—地质矿产勘探]