特高含水油藏复杂韵律层重组模式研究

确定了复杂韵律层的8个评价指标,分别为渗透率、渗透率变异系数、存储能力、流动能力、剩余油可采储量丰度、油相流度、水相流度、弱水淹系数;运用层次分析法确定了各指标的层次结构及其权重,利用模糊评判的方法确定了各井区的综合指数;通过建立典型模型,运用数值模拟预测法和最优分割法,制定了复杂韵律层重组的技术政策界限。通过对胜利油田坨七断块顶部油藏复杂韵律层重组的数值模拟研究,预测韵律层重组和在重组基础上适当加密井网2个方案5年后采出程度分别增加0.44%和1.42%,含水率同比分别下降0.54%和0.44%。说明提出的复杂韵律层重组模式能有效改善特高含水砂岩油藏水驱开发效果。

Mode of Rhythmite Reconstruction in the Reservoirs with Extra High Water Cut

Eight evaluating indexes for complex rhythemites are determined, which include permeability, its coefficient of variation, oil storage capacity, flow capacity, abundance of recoverable reserves of remaining oil, oil mobility, water mobility and weak water-out coefficient. Hierachical analytical method is used to determine the hierachical structure and weight of each index, and a fuzzy evaluating method is used to establish the integrated indexes of each well block. The limit of technical policies for complex rhythmite reconstruction is developed by establishing typical model and using numerical modeling predicting method and optimal segmentation. Through a study of numerical simulation of rhythmite reconstruction of reservoirs on the top of Fault Block Tuo 7 in Shengli Oilfield, 2 schemes of rhythmite reconstruction prediction and properly infilled well pattern are deployed with recovery percent increase 0.44% and 1.42% respectively and water cut decrease 0.54% and 0.44% respectively 5 years later. It indicates that the mode of complex rhythmite reconstruction can be used to effectively improve the development result in sandstone reservoirs with extra-high water cut.