Prestack decoupled stepwise inversion harmonized with physical and data prior knowledge
Amplitude-versus-angle(AVA)inversion plays an important role in the prediction of reservoir elastic parameters.The angles of the AVA equation(physical prior knowledge)are not easily determined,and the ill-posed nature of the large sparse matrix will make the conventional prestack inversion procedure unstable.For this reason,a prestack decoupled stepwise inversion method harmonized with physical and data prior knowledge is proposed.Firstly,a non-sparse forward framework is established based on physical knowledge to increase the stability of parameter inversion and lay the foundation for decoupled stepwise inversion.Next,this paper takes well data as data prior knowledge and harmonizes it with physical and data prior knowledge to decouple the prestack seismic data for more accurate prestack seismic attributes.Finally,inversion of decoupled prestack seismic attributes is performed to get the reservoir elastic parameters.This method can correct the inversion procedure by well logging prior information,which can avoid the errors caused by the inaccurate angles in the physical prior knowledge.The actual data test results show that the inversion results of the proposed method have higher accuracy compared with the industrial AVA inversion method.In addition,the inversion results of this method have higher accuracy,in which the accuracy of the lame parameter,shear modulus,and density is improved by 14.1％,13.6％,and 11.9％,respectively.
万方数据
维普
