地球介质非线性与各向异性的地震波响应及其成像效应

The practice of geophysical prospecting shows us the complex interior earth. The studies of the complexity play an important role and practical guide for the subsurface structure. At present, the complexity of the earth mainly means lateral and vertical homogeneity, anisotropy and non-linear quality. And the anisotropy and non-linear media studies become the frontier in seismology and exploration seismology. This paper summarizes the development of complexities and presents the forward and inverse in the non-linear and anisotropic media. Firstly, the paper introduces the theory of seismic wave propagation in the non-linear and anisotropic media, the theoretical basis for simulation and inversion research. Secondly, high quality numerical simulation method with little dispersion has been developed to investigate the influence of complexity including anisotropy and non-linear multi-component seismograms. Because most real data in seismology have a single component, we developed two aspects work on anisotropic multi-component imaging. One is prestack reflection migration. The result show that distorted images are obtained if data from anisotropic media are migrated using isotropic extrapolation. Moreover, image quality will be improved greatly after considering anisotropy in subsurface layers. The other one is the we take advantage of multi-component data to inversion of the anisotropic parameters jointly seimic reflection travel time and polarization information. Based on these research works, we get the following results: 1.Combing numerical simulation, systematical studies indicate that anisotropy and non-linear seismograms characters are significant to detect cracked belts in the earth and to understand deformation field and mechanism. 2.Based on anisotropic media models, we developed an efficient prestack migration method for subsurface structure and different observation methods seismic data, which improving the imaging quality with VSP, seismograms and real data. 3.Jointly seismic inversion combining seismic anisotropic reflection traveltimes and polarizations data show that the complete wrong inversion and the following explanation will be resulted by ignoring anisotropy.