渭北油田阵列感应测井数据反演

Inversion of Arry Induction Log in Weibei Oilfield

渭北油田储层物性主要为低孔超低渗储层。对于低孔低渗储层孔隙结构复杂,泥质对电性响应贡献加大,地层电阻率求取不准确。针对渭北油田钻井液侵入过程中储层径向电阻率的变化特征,构建渭北油田地层侵入模型。利用阵列感应测井资料对地层参数进行反演,能较好地反映不同侵入特征的储层电阻率分布形态;可较好地重构储层电阻率剖面,获取原状地层电阻率,侵入带电阻率和侵入半径;反演算法稳定可靠,能对实际测井资料进行连续快速处理,更有助于定量、精确地计算渭北油田储层含油饱和度和识别储层流体性质。

The reservoir physical property of Webei oil field is low porosity and permeability. As the pore structure of the reservoir with low porosity and permeability is complex, influence of the shale on the electric nature accretes and the electric resistivity of the formation is not exact. In view of the varying feature of the radial electric resistivity during the intruding process of the drill fluid, the intruding model of Weibei oil field was established. The array induction log data were used to invert parameters of the formation, which could reflect the distribution of electric resistivity when intruding the reservoir differently, and reconstitute the electric resistivity section of reservoir preferably, and acquire the electric resistivity of undisturbed zone and invaded zone, and invasion radius. The inversion algorism is steady and reliable, it can process the actual well logging data continuously and speedily, and it is more helpful to calculate the oil saturation quantitatively and accurately of Weibei oil field and identify the fluid property of reservoir.