块状气顶底水油气藏低渗透夹层研究

A RESEARCH METHOD OF LOW PERMEABILITY INTERBEDS WITHIN A MASSIVE PETROLEUM RESERVOIR WITH GAS CAP AND BOTTOM WATER

块状气顶底水油气藏储集层中低渗透夹层的分布是影响油气藏开发方法及开发效果的关键地质因素。低渗透夹层的垂向渗透性及分布范围直接影响着气窜及底水锥进速度，对开发井射孔井段的选择及开发指标预算起着重要作用。通过塔中４油田ＣⅢ油组实例研究，论述了储集层沉积相分析、层序地层学研究在夹层成因与分布范围及侧向追踪对比方面的应用，讨论了低渗透夹层类型划分、级别划分的方法，及其在三维地质模型中的体现。

The distribution of low permeability interbeds within a massive petroleum reservoir with gas cap and bottom water is a key geologic factor affecting the development method and result of the oilfield. The vertical permeability and the distribution of the interbeds have a direct innuence on the speed of gas breakthrough and water coning, the determination of perforation interval of the production wells and the prediction of the production indexes. Through a case study of Tazhong-4 oilfield, this paper has discussed the application of reservoir sedimentary environment analysis and sequence stratigraphic analysis to the prediction and lateral correlation of interbeds, and to the classification of types and grades of the interbeds. The expressing methods of the interbeds in the 3D geologic model are also discussed in the paper.