基于井间动态连通性计算低渗油藏窜流通道

低渗透油藏窜流通道的普遍发育造成注水开发效果变差。为此,提出了基于低渗透油藏井间动态连通性研究定量计算窜流通道的方法。利用井间连通性模型计算得到注采井间连通系数将由注水井注入、窜流通道产出的未起到驱油效果的无效循环水劈分到各注采方向,进而定量计算出各注采方向上窜流通道的体积和渗透率等物理参数。现场应用结果表明:该方法可有效描述低渗透油藏的窜流通道,为调剖措施的实施提供指导,具有一定的矿场应用价值。

Characterization of thief zones using interwell dynamic connectivity in low permeability reservoir

For low permeability oilfields, widespread evolution of thief zones will lead to circulating inefficiently of injection water. A new approach to describe thief zones based on interwell dynamic connectivity model is proposed in this work. The excess water is calculated based on threshold pressure gradient equation. Then using the dynamic connectivity coefficient inversed from multivariate linear regression model, the excess water is divided into each injector-producer direction, and then physical parameters of thief zones are obtained by ordinary reservoir engineering method. This approach has been applied to Changqing Oilfield, and the result is in good agreement with that of profile control and water shutoff, which has verified its effectiveness.