文留油田流动单元识别及随机模拟——以文135断块油藏沙二下储层为例

Identification and stochastic simulation of the flow units in Wenliu Oilfield:taking the lower section of S2 in Wen-135 block fault block reservoir as an example

流动单元的随机模拟是预测剩余油分布的有效手段.以文留油田文135断块油藏沙二下储层为例,提出了针对复杂断块油气田流动单元的研究思路和步骤.选取孔隙度、渗透率、有效厚度、地层系数、有效储集系数及流动指数等6个参数,应用聚类分析方法,将储层划分为E、G、P 3类流动单元,并采用序贯高斯随机模拟方法建立了流动单元三维定量模型.认为:E类流动单元动用较好,其剩余油分布主要因断层遮挡所致;G类流动单元由于层间或平面非均质性的影响,动用程度较低,剩余油富集;P类流动单元由于渗流能力差,且储量丰度低,动用难度大.

The stochastic simulation of flow units is an effective means for predicting remaining oil distribution.A new approach to study the flow units in complex fault-block oil/gas fields is put forward and the study steps are proposed by taking the lower section of S2 in Wen-135 block fault block reservoir as an example.The reservoir is divided into three types of flow units of E,P and G by cluster analysis,and porosity,permeability,effective sandstone thickness,formation coefficient,effective storage coefficient and flow index are used as cluster parameters.A quantitative 3-D flow unit model is established by using sequential Gaussian stochastic simulation.It is held that E type of flow units are well exploited,whose remaining oil is caused by fault barrier,G type of flow units are worse exploited,whose rich remaining oil is caused by interlayer or lateral heterogeneity,and P type of flow units are exploited the worst because of the poor percolation and a lower reserves abundance.