Separation of diffracted waves via SVD filter

Petroleum Science

Qin Li¹  Yue-Ying Yan¹  Xin-Xin Li²  Jing Zhao²  Hong-Yan Shen² 

[1] School of Earth Sciences and Engineering, Xi’an Shiyou University, 710065, Xi’an, Shaanxi, China;School of Earth Sciences and Engineering, Xi’an Shiyou University, 710065, Xi’an, Shaanxi, China;Key Laboratory of Shaanxi Province for Oil and Gas Accumulation Geology, 710065, Xi’an, Shaanxi, China;

关键词: Geological heterogeneity;    Reflected waves;    Diffracted waves;    SVD filter;    Seismic wave field separation;    Migration imaging;   

DOI  :  10.1007/s12182-020-00480-8

来源: Springer

【 摘 要 】

Diffracted seismic waves may be used to help identify and track geologically heterogeneous bodies or zones. However, the energy of diffracted waves is weaker than that of reflections. Therefore, the extraction of diffracted waves is the basis for the effective utilization of diffracted waves. Based on the difference in travel times between diffracted and reflected waves, we developed a method for separating the diffracted waves via singular value decomposition filters and presented an effective processing flowchart for diffracted wave separation and imaging. The research results show that the horizontally coherent difference between the reflected and diffracted waves can be further improved using normal move-out (NMO) correction. Then, a band-rank or high-rank approximation is used to suppress the reflected waves with better transverse coherence. Following, separation of reflected and diffracted waves is achieved after the filtered data are transformed into the original data domain by inverse NMO. Synthetic and field examples show that our proposed method has the advantages of fewer constraints, fast processing speed and complete extraction of diffracted waves. And the diffracted wave imaging results can effectively improve the identification accuracy of geological heterogeneous bodies or zones.

【 授权许可】

CC BY