鲁棒性AVO三参数反演方法及不确定性分析

Robust three-term AVO inversion and uncertainty analysis

密度可用于推测流体饱和度,在储层预测中起至关重要作用。本文针对反演密度项造成的不适定问题和地震资料的带限特征,提出一种鲁棒性AVO三参数反演方法。该方法是通过在概率化AVO三参数反演目标函数中加入正则约束项,反演得到纵横波阻抗及密度参数,在提高反演结果稀疏性的同时,对反演结果低频分量进行补偿,保证结果的可靠性。文中还对反演结果进行了不确定性分析,验证了反演结果的可信程度。模型试算和实际资料测试结果均表明该方法具有可行性。

As density can be used to estimate fluid saturation,it plays an important role in reservoir prediction.However,it is difficult to estimate accurate parameters due to the ill-conditioned nature of inverse problems and the band-limited nature of seismic data.In order to stabilize inversion and improve the reliability and sparsity of inversion result,we add regularization terms to the objective function of probabilistic three-term AVO inversion to estimate P-wave,S-wave impedance and density.Although the regularization strategy is applied,uncertainty in parameter estimation still exits.Thus,we apply uncertainty analysis to determine if the estimation is desirable.At last,the algorithm is tested on synthetic data and seismic data.Both results show that the method is feasible.