复杂断块油藏原始含油饱和度场分布模型研究

摘要

针对复杂断块油藏受储层非均质性、孔隙结构差异及流体毛管力等因素影响,导致原始含油饱和度分布空间差异难于准确表征的问题,基于岩样原始含油饱和度恢复资料,通过分析原始含油饱和度、束缚水饱和度对应毛管压力端点值与储层特征参数的相互关系,构建了原始含油饱和度、毛管压力端点值与储层流动区域指数、油柱高度的关系式,考虑油藏三维空间孔渗分布规律,建立了随储层特征参数变化的油藏原始含油饱和度场分布模型.研究结果表明,文中方法计算的开发早期井原始含油饱和度与测井解释结果绝对误差小于0.03.研究成果对精细表征复杂断块油藏原始含油饱和度场随储层空间变化的差异有重要意义.%Due to impacts of reservoir heterogeneity, differences in pore structures, fluid capillary forces and other factors, it is extremely difficult to characterize differences in spatial distribution of original oil saturation in complex fault block reservoirs.Under such circumstances, original oil saturation restoration data of rock samples have been used to establish the correlation among original oil saturation, capillary pressure endpoint values and reservoir flow region index, oil column height by analyzing the relationship among original oil saturation, irreducible water saturation, corresponding capillary pressure endpoint values and reservoir characteristic parameters.With consideration to 3D distribution patterns of porosity and permeability in reservoir formations, models for distribution of original oil saturation fields with changes in characteristic parameters of reservoirs.Research results show the absolute error between the original oil saturation in early development stages of producers determined by using the method introduced in this Paper and the logging data interpretation results are less than 0.03.Relevant research results are of great importance for detailed characterization of changes of original oil saturation fields in complex fault block reservoirs with spatial changes of reservoirs.