中基性火山岩体积压裂水平井增产预测图版及其应用

Predicting chart and its case study for volume fractured horizontal well in the intermediate-basic volcanic reservoirs

松辽盆地中基性火山岩储层渗流机理复杂,采用常规数值模拟方法预测产量准确率低、耗时长,缺少适用的压裂后增产预测图版。根据储层人工裂缝+天然裂缝+基质三重介质特征,对体积压裂储层改造区建立了考虑应力敏感、启动压力梯度、滑脱效应和高速非达西效应影响的数学模型,研究了多效应影响下的压裂后日产气量和改造体积(SRV)随段间距的变化规律。结果表明,根据计算结果建立的中基性火山岩储层的增产预测图版在大庆油田现场应用,产能预测误差不超过7%,预测效果优于常规数值模拟预测方法。预测图版在中基性火山岩体积压裂水平井增产预测时准确、高效、方便,对现场压裂施工设计具有一定的指导和借鉴意义。

Due to the complex seeping mechanism of the intermediate-basic volcanic reservoirs in Songliao Basin,the conventional numerical simulation method is of low accuracy and time-consuming to predict the production,and there is lack of a suitable predicting chart for post-fracture stimulation.According to the characteristics of triple media including reservoir artificial fracture,natural fracture and matrix,the mathematical model considering the influences of the stress sensitivity,staring pressure gradient,slippage effect and high-speed non-Darcy effect was established in the stimulated reservoir volume(SRV)area,moreover,the changed law of the post-frac daily gas production and SRV with the stage spacing under the influences of the multiple effects was studied.The results show that according to the calculated results,the established simulation predicting chart of the intermediate-basic volcanic reservoirs was applied in Daqing Oilfield,the productivity prediction error is less than 7%and the predicted effect is much better than that of the conventional numerical simulation method.The predicting chart is accurate,high-efficiency and convenient in predicting the stimulated production of the SRV horizontal well in the intermediate-basic volcanic reservoirs,which provides certain guidance and reference for the field fracturing design.