基于AVO流体反演的储层孔隙度预测技术

AVO流体反演技术是将统计学与AVO理论结合,统计判别实际地震数据与测井数据正演的AVO响应,定量预测目标储层的含油气概率分布。针对低孔、低渗碎屑岩储层,为求取孔隙度参数,本文将AVO流体反演技术进行了改进,充分利用其统计学分析优势,通过贝叶斯和柯西等概率理论对异常信息进行统计判别,并从中提取出储层的孔隙度信息,实现了X69井区储层的定量预测,减小了预测的多解性。孔隙度预测结果与实际测井值吻合率最高可达到79%,较好刻画出高产井区有效储层空间分布特征。

Reservoir porosity prediction based on AVO fluid inversion

AVO fluid inversion is a program which combines AVO theory with statistics,discriminates the AVO response between actual seismic data and log data,and predict quantificationally the probability of hydrocarbon in reservoirs.To obtain the quantificational porosity prediction of low-porosity and low-permeability reservoirs at target area,we present in this paper an improvement of AVO fluid inversion to make full use of its advantages in statistical analysis with probability theory such as Bayes’ theorem and Cauchy distribution,to distinguish anomaly information and extract effective information about reservoir porosity.The prediction results in X69 area show that 79% of the prediction fit to the calculated values of logging data,and the distribution of effective reservoirs in high productivity area is accurately delineated.