PP And PS Waves Joint AVO Inversion

Amplitude versus offset(AVO)inversion is a seismic prestack inversion technique for estimating elastic subsurface parameters to predict hydrocarbon.However,the conventional methods of S-wave velocity and density parameters estimation use P-wave data alone,which may be unstable and inaccurate because of seismic data with noise.While multi-wave and-component seismic exploration technology could supply a great of PS information,which contribute to S-wave velocity and density inversion.Therefore,in this paper,we carry out a study on methodology of PP and PS waves joint AVO inversion.To solve the ill-posed problem in three-term AVO inversion,From determinacy inversion algorithm,we put PS waves information into PP wave log-constrained inversion to solve the ill-posed problem occurring in three parameters AVO inversion.And from statistical inversion algorithm,we put forward the method of PP and PS waves joint AVO inversion under the Bayesian theory.As we all know,log-constrained inversion and Bayesian inversion theory all required the well data support.So when there wells information not enough,three parameters AVO inversion containing still exist low precision caused by the density.Therefore,in this paper,we proposed AVO inversion method with PP and PS waves step by step joint AVO inversion.We can get velocity of P-wave and S-wave velocity from first two parameters inversion,then,regarding P-wave velocity as known information,we get S-wave velocity and density from the second two parameters joint inversion.By making secondary two parameters inversion,we effectively solve the il-posed problem from the three parameters inversion.In this paper,via synthesizing seismic record by log data,Marmousi2 model and the real data test examples show the stability and unambiguity of PP and PS waves joint AVO inversion.Several kinds of joint PP and PS waves AVO inversion method we proposed in this paper can be used for reservoir and hydrocarbon prediction.