基于密度分析的含气饱和度预测研究应用

Research and Application of Gas Saturation Prediction Based on Density Analysis

Z区块多口井均有气层发现,且单井钻遇的气层多,总气层厚度大,在地震剖面上能看到同相轴变粗、下拉、低频等含气特征。该区形成"亮点"的原因很多,不同饱和度的气层和含气水层均为强振幅反射,研究认为Z区含气性识别的难点不在于区分气层与水层,而是含气饱和度的定量预测。在叠前反演和岩石物理分析的基础上,应用敏感参数扰动实验,识别了反映饱和度变化的敏感参数,取得敏感参数随饱和度变化的关系,并利用该关系对海外已含油气盆地进行了应用效果的验证。

Many gas wells were discovered in Z blocks,and the number of gas layer is larger in single well and the total gas is thick.In the seismic profile,the gas-bearing event features in higher thickness,dropping down and low frequency.There are many reasons for òbright spotó in this area,and the gas and gas-water layer of different saturation is strong in amplitude.Studies suggest that it is not difficult to identify the distinction between the water and gas,but the quantitative prediction of gas saturation.In this paper,based on pre-stack inversion and rock physics analysis,perturbation experiments were conducted to identify the sensitive parameter for saturation and obtained the sensitive parameter and the relationship between the density and saturation.Finally the relationship was used to examine the application effect in overseas oil and gas basins.