Nonstationary signal inversion based on shaping regularization for random noise attenuation*
Yang Wu-Yang 1, Wang Wei 1, Li Guo-Fa 2,3, Wei Xin-Jian 1, Wang Wan-Li 1, and Chen De-wu 1
1. Research Institute of Petroleum Exploration & Development-Northwest, PetroChina, Lanzhou 730020, China.
2. State Key Laboratory of Petroleum Resources and Prospecting, CUP (Beijing), Beijing 102249, China.
3. CNPC Key Laboratory of Geophysical Prospecting, CUP (Beijing), Beijing 102249, China.
Abstract Prediction filtering is one of the most commonly used random noise attenuation methods in the industry; however, it has two drawbacks. First, it assumes that the seismic signals are piecewise stationary and linear. However, the seismic signal exhibits nonstationary due to the complexity of the underground structure. Second, the method predicts noise from seismic data by convolving with a prediction error filter (PEF), which applies inconsistent noise models before and after denoising. Therefore, the assumptions and model inconsistencies weaken conventional prediction filtering's performance in noise attenuation and signal preservation. In this paper, we propose a nonstationary signal inversion based on shaping regularization for random noise attenuation. The main idea of the method is to use the nonstationary prediction operator (NPO) to describe the complex structure and obtain seismic signals using nonstationary signal inversion instead of convolution. Different from the convolutional predicting filtering, the proposed method uses NPO as the regularization constraint to directly invert the effective signal from the noisy seismic data. The NPO varies in time and space, enabling the inversion system to describe complex (nonstationary and nonlinear) underground geological structures in detail. Processing synthetic and field data results demonstrate that the method effectively suppresses random noise and preserves seismic reflection signals for nonstationary seismic data.
Corresponding Authors: Wang Wei (Email: ww_geophy@126.com)
E-mail: ww_geophy@126.com
About author: Yang Wuyang, Ph.D., senior technical expert of CNPC,graduated from Graduate School of the Chinese Academy of Geological Sciences in 2005, currently working in heterogeneous reservoir prediction, fractures modeling, and intelligent geophysical exploration. Email: yangwuyang@petrochina.com.cn
Wang Wei (Communication author), a master's degree in geological resources and geological engineering from China University of Petroleum (Beijing) in 2018, currently working in the Institute of Geophysics, Northwest Branch of China Petroleum Exploration and Development Research Institute, mainly engaged in intelligent geophysical exploration, signal processing, and software development.Email: wangwei_geophy@petrochina.com.cn
Cite this article:
. Nonstationary signal inversion based on shaping regularization for random noise attenuation*[J]. APPLIED GEOPHYSICS, 2020, 17(3): 432-442.
2020, Vol. 17 
