河流相储层层理构型建模方法及等效渗透率计算

Modeling method and equivalent permeability calculation of fluvial reservoir formation configuration

渗透率是储层非均质性的关键表征参数,其精准计算是油藏数值模拟精准预测的前提条件。岩心塞由于尺度小,测量的方向渗透率各向异性小,均质性强,无法反映储层中更大尺度层理的非均质性,在应用于油藏数值模拟时,历史拟合精度低,与生产动态偏差大。为解决这一问题,提出了一种层理构型建模及方向渗透率计算方法,该方法利用正弦函数描述三维纹层面,通过迁移正弦函数将纹层面组合成层理几何模型,然后构建层理的岩相及岩石物理属性模型,实现层理构型的定量表征。最后,提出了一种单相流动模拟方法实现了层理模型等效方向渗透率的定量计算。该方法应用于渤海Q油田河流相储层,有效提高了模型历史拟合精度,具有明显的推广应用价值。

Permeability is a critical characteristic parameter of reservoir heterogeneity,and its accurate calculation is a prerequisite for accurate prediction of reservoir numerical simulation.Due to the small size of the core plug,the measured directional permeability is less anisotropic and highly homogeneous,which cannot reflect the heterogeneity of larger-scale stratification in the reservoir.When applied to reservoir numerical simulation,the historical fitting accuracy could be lower and deviate significantly from the production dynamics.In order to solve this problem,a method for modeling bedding configuration and calculating the directional permeability is proposed.The method uses the sine function to describe three-dimensional laminae,combines laminae into a bedding geometric model through the transfer sine function,and then constructs the bedding’s lithofacies and petrophysical property model to realize the bedding configuration’s quantitative characterization.Finally,a single-phase flow simulation method is proposed to calculate the equivalent directional permeability of the stratification model quantitatively.This method is applied to the fluvial-facies reservoir in the Q Oilfield of the Bohai Sea,which effectively improves the historical fitting accuracy of the model and has obvious application value.