Sparse constrained encoding multi-source full waveform inversion method based on K-SVD dictionary learning*
Guo Yun-dong 1,3, Huang Jian-Ping 1,2, Cui Chao 1,2, LI Zhen-Chun 1,2, LI Qing-Yang 1,3, and Wei Wei 4
1. School of Geosciences, China University of Petroleum (East China), Qingdao 266580, China;
2. Laboratory for Marine Mineral Resources, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266071, China
3. Geophysical Exploration Research Institute of Zhongyuan Oilfi eld Company, Puyang 457001, China
4. SINOPEC Petroleum Exploration and Production Research Institute, Beijing 100083, China
Abstract:
Full waveform inversion (FWI) is an extremely important velocity-model-building method. However, it involves a large amount of calculation, which hindsers its practical application. The multi-source technology can reduce the number of forward modeling shots during the inversion process, thereby improving the efficiency. However, it introduces crossnoise problems. In this paper, we propose a sparse constrained encoding multi-source FWI method based on K-SVD dictionary learning. The phase encoding technology is introduced to reduce crosstalk noise, whereas the K-SVD dictionary learning method is used to obtain the basis of the transformation according to the characteristics of the inversion results. The multiscale inversion method is adopted to further enhance the stability of FWI. Finally, the synthetic subsag model and the Marmousi model are set to test the eff ectiveness of the newly proposed method. Analysis of the results suggest the following: (1) The new method can effectively reduce the computational complexity of FWI while ensuring inversion accuracy and stability; (2) The proposed method can be combined with the time-domain multi-scale FWI strategy fl exibly to further avoid the local minimum and to improve the stability of inversion, which is of signifi cant importance for the inversion of the complex model.