基于f-x域时频非凸正则化低秩矩阵近似的共偏移距道集去噪方法  

Random noise attenuation of common offset gathers by f-x low-rank matrix approximation with nonconvex regularization

作　　者：石战战 庞溯[2,3] 王元君 池跃龙 周强[2,3] SHI Zhan-Zhan;PANG Su;WANG Yuan-Jun;CHI Yue-Long;ZHOU Qiang(School of Artificial Intelligence,Leshan Normal University,Leshan 614000,China;The Engineering and Technical College,Chengdu University of Technology,Leshan 614000,China;College of Geophysics,Chengdu University of Technology,Chengdu 610059,China;School of Land and Resources,China West Normal University,Nanchong 637002,China)

机构地区：[1]乐山师范学院人工智能学院,四川乐山614000 [2]成都理工大学工程技术学院,四川乐山614000 [3]成都理工大学地球物理学院,四川成都610059 [4]西华师范大学国土资源学院,四川南充637002

出　　处：《物探与化探》2022年第6期1444-1453,共10页Geophysical and Geochemical Exploration

基　　金：国家科技重大专项课题(2016ZX05026-001);四川省教育厅项目(16ZB0410);川西南空间效应探测与应用四川省高等学校重点实验室开放基金(YBXM202102001);四川旅游发展研究中心课题(LY22-20)。

摘　　要：随机噪声压制是地震数据处理的关键环节,而时频稀疏低秩近似算法逐道处理地震数据过程中无法利用信号的道间相干性。为此,将时频稀疏低秩近似与f-x域去噪结合,提出一种f-x域时频非凸正则化低秩矩阵近似算法。该算法对f-x域中每一单频分量作时频分解后,再对时频系数矩阵作低秩矩阵近似计算,能够利用信号和噪声的时频谱差异实现非平稳信号去噪处理。与共炮点道集和共中心点道集相比,共偏移距道集具有平缓甚至接近水平的同相轴结构,基本满足f-x域去噪的线性同相轴假设前提,建议将所提算法应用于共偏移距道集去噪处理。通过数值模拟和实际地震数据试算,证明本文方法能够有效压制随机噪声,同时保持有效信号不被损害。Random noise attenuation played an important role in the seismic data processing.The low-rank estimation of the seismic signal in the time-frequency domain is essentially a trace-by-trace process,which cannot exploit the channel-to-channel coherence of the signal.We propose a novel random noise attenuation based on f-x low-rank matrix approximation with nonconvex regularization.Firstly,the noisy seismic data is transformed into the f-x domain by Fourier transform.Then,the time-frequency method is employed to decompose each discrete frequency slice.Finally,we estimate the sparse low-rank matrix from the obtained noisy matrix.This method enables the denoising of non-stationary signals by exploiting the spectral differences between signal and noise.Compared with the common shot and mid-point gathers,the common offset gather is characterized by flat events,which basically satisfies the assumption of linear events for f-x domain denoising,and it is suggested that the proposed algorithm should be applied to the common offset gather.Synthetic and real data sets demonstrate the performance of our proposed method in random noise suppression and preserving more useful energy.

关 键 词：F-X域 时频域 低秩矩阵近似 共偏移距道集 随机噪声 

分 类 号：P631.4[天文地球—地质矿产勘探]