低渗特低渗储层水锁损害定量预测方法

在低渗特低渗油气藏开发过程中储层损害严重,其中水锁损害是主要损害之一,因此建立准确、快速定量预测水锁损害程度的数学模型,对高效开发低渗透油田具有重要意义。采用线性回归分析法建立的水锁损害预测模型不能准确反映储层损害实质,预测精度较低。将常规线性回归模型转变为非线性回归模型,能够更好地反映各损害因素与损害程度间的关系;采用逐步回归法选择回归因子,建立了新的水锁损害定量预测模型,并对新模型进行了检验。结果表明,新建立的水锁损害定量预测模型预测结果准确性高,15组验证样本的预测准确率均大于80%,平均预测准确率为91.69%,可为油气层保护和储层解堵措施优化设计提供科学依据。 

The Quantitative Prediction Method of Water Blocking Damage in Low and Extra-Low Permeability Reservoir

There are very serious damages during the exploitation of low permeability and extra-low permeability reservoirs,and water blocking is the most remarkable damage.So the mathematical model which can accurately and rapidly predict water blocking damage level will play an important role in the effective development of low permeability oilfield.Linear regression analysis was used to establish prediction model of water blocking damage in the past,but the model could not accurately reflect the real damage essence to the reservoir,especially the prediction accuracy was low.As we all know that the non-linear regression model can better reflect the relationship between damage factors and extent of damage than the conventional linear regression model.The stepwise regression method was adopted to select regression factors and the new water blocking damage prediction model was established.The test results for the new model indicated that,the new model had higher accuracy than the conventional one,for example,the prediction accuracy rate of 15 tested samples were greater than 80%,and the average prediction accuracy rate was 91.69%.It will provide evidence for reservoir protection and measures to optimize the design of reservoir unplugging.