论文详情
为了解决常规各向同性介质三参数反演方程难以满足各向异性介质四参数反演的问题,同时也为了解决难以获取测井各向异性信息的问题,建立了基于零约束的各向异性梯度四参数反演方程,提出了裂缝型储层预测的各向异性梯度反演反法。首先根据贝叶斯理论建立各向异性梯度四参数反演目标函数;然后将待反演参数零约束项加入到目标函数中,得到基于零约束的各向异性梯度四参数反演方程;求解该反演方程,得到各向异性梯度最大似然解,据此预测裂缝型储层。实际资料应用结果表明,该方法反演的各向异性梯度异常与钻井的裂缝发育区位置吻合,说明基于零约束的各向异性梯度四参数反演方法可以为裂缝型储层预测提供有效的技术支撑。
It is difficult to meet the demand for an anisotropic four-term inversion using an isotropic three-term inversion equation.Furthermore,obtaining anisotropic logging information as constraint can be challenging.Given this context,the study proposes an anisotropic four-term inversion equation with zero constraints.First,we build an anisotropic gradient four-term inversion objective function according to Bayesian theory.Then,a zero constraint term on the inversion parameters is added to the objective function to obtain an anisotropic four-term inversion equation with zero constraints.Finally,the equation is solved to obtain the maximum likelihood solution for an anisotropic gradient.Field data tests show that the anisotropic gradient anomalies inversion is in agreement with the fracture development zone position located with drilling data,which indicates that the proposed method is effective for fractured reservoir prediction.
Keywords: fracture,anisotropic gradient,zero constraint,inversion,maximum likelihood solution
国家科技重大专项“亚太地区油气资源评价及未来战略发展方向”(2011ZX05028-006)和中海石油(中国)有限公司科技项目“巴新弧后前陆区复杂构造与油气成藏机制研究”(YXKY-2017-ZY-02)共同资助。