Prestack Joint Inversion Based On PP And PS Seismic Data

With the development of multi-component seismic data acquisition and processing technology,seismic exploration based on multi-component seismic data has gradually been an important subject in oil and gas exploration.In this paper,we studied some key problems for multi-component exploration technology from two perspectives of prestack data preprocessing and elastic parameters inversion.Prestack data preprocessing is the key to the success of prestack inversion.Multiple attenuation is an important step of the seismic preprocessing,especially for Marine seismic data,the result of multiples suppression will greatly affect the result of structural imaging and reservoir inversion.In this paper,Radon transform is used to attenuate the multiples in seismic data.A high-order,high resolution Radon transform with L1-2 regularization is proposed to achieve high resolution,high amplitude preservation and high computational efficiency of multiples attenuation.In addition,the Radon algorithm is extended to 3D case to process 3D seismic data.PP and PS data registration is the basis of joint inversion.However,mapping PS data to the PP time domain leads to uneven compression of PS data,and then we cannot extract a uniform seismic wavelet in it,which will degrade the subsequent inversion results.In order to correct the PS waveform after registration,a time-frequency adaptive shaping filter is proposed.Compared to the conventional method,the proposed method is more robust.For elastic parameters inversion,a new inversion strategy is proposed,which constructs the Jacobian matrix by the linearized forward operator and calculates the synthetic data by the exact Zoeppritz equation.Compared with the conventional joint inversion method,the proposed method can obtain accurate inversion results and has high computational efficiency.In addition,we extend the algorithm to a multi-trace inversion case to mitigate the lateral discontinuities in inversion results caused by PP and PS registration.By solving the 1D wave equation,a joint inversion method based on the reflectivity method is proposed.Compared with the exact Zoeppritz equation,the reflectivity method can simulate the propagation of the seismic wave in underground media,and therefore,it is more consistent with the actual seismic wave propagation.In addition,the reflectivity method can take into account not only the amplitude,but also the phase and traveltime of seismic waves.In theory,the reflectivity-based joint inversion method can simplify or avoid the tedious process of PP and PS registration.However,due to the large computational burden,the reflectivity-based inversion method is not extended to the multi-trace case.The lateral continuity is improved by applying a frequency spatial domain prediction error filtering on the inversion results.Examples from both synthetic and field data demonstrate the effectiveness and feasibility of the proposed methods.