The Research Of Nonstationary Seismic Sparse Inversion In Frequency-domain

Seismic inversion in different domain is utilized to get reflectivity information by considering the fitting degree between real seismic response and synthetic seismogram.Seismic inversion in frequency domain is implemented to yield the information of stratigraphic impedance using partial frequency components of band-limited seismic.Considering the time domain inversion's quality of anti-noise and the superior resolution of frequency domain inversion,we jointed the frequency domain inversion theory and Bayesian framework and then proposed one robust seismic multi-scale inversion method with smooth model constraint in frequency domain.As a result,it improved the ability to suppress noise and lateral continuity of the inversion result by using smooth model regularization.In addition,since different frequency components of real seismic gathers can realize decoupling in frequency domain,we can carry out our method by successive iterations of different frequency components to decrease the model-dependent problem.Applications on stationary seismic theoretical tests and real cases demonstrated the feasibility and stability of our method.Sparse seismic inversion is an effective strategy to restrict the sparsity of reflection coefficients in final object function.Matching pursuit algorithm is utilized to realize the adaptive decomposition of signals.Besides,we always can achieve the optimum solution of inverse problem after several iterations.Considering the excellent anti-noise property of sparse inversion,we proposed one novel mix-domain sparse AVO inversion utilizing fast matching pursuit algorithm.In our work,the mixed frequency-domain model introduced by Margrave(1998)is regarded as the forward equation.Firstly,the object function is constructed with fast matching pursuit algorithm.And the low-frequency constraint is also introduced into inversion process to enhance the stability of inversion algorithm.Conventional matching pursuit inversion can only obtain one optimal atom after an iteration which can achieve the maximum absolute value in inner product space.However,fast multi-atom matching algorithm obtains more than one atoms which can improve the computation speed and convergence precision effectively.In addition,we illustrate the feasibility and excellent stability through several synthetic tests.Finally,superior inversion results with our method can also maintain a higher fitting degree to the real logging data.Matching pursuit algorithm is utilized to realize the adaptive decomposition of signals.In order to make full use of the amplitude and frequency anomaly information containing in pre-stack seismic data,we analyze FAVO reflection equations for fluid factor incorporating with MP-spectral decomposition algorithm.Finally,the FAVO directly inversion in time-frequency domain with superior resolution was proposed in this paper.Most of all,the procedure of spectral-balanced was built in objective function as well.So the proposed method reduced the middle stages of extraction for dispersion attributes and avoided the accumulated errors which were introduced in the process of eliminating wavelet overprint.In the end of this paper,synthetic tests and one field case demonstrate the ability to describe the accurate boundary position of the reservoir with MP-FAVO(frequency-dependent AVO)inversion.The proposed method can detect the fluid properties in the reservoir effectively.Conventional seismic inversion methods are often established on stationary convolution model.However,due to the heterogeneity and viscoelasticity of underground medium,attenuation effects of seismic wave will happen.Because of the amplitude's attenuation,phase distortion,and narrow frequency band,the resolution of the seismic record is reduced greatly.The inverse Q filtering and Gabor deconvolution is an effective method to improve seismic resolution.In this paper,we joint Gabor deconvolution and regularization inversion method and propose one high resolution sparse inversion method based on seismic self-adaptive attenuation compensation.Considering the attenuation and dispersion of seismic wave of complex medium in the process of inversion,the final synthetic tests and field case study demonstrated that our method can improved the seismic resolution of deep strata effectively.