页岩气藏不稳定压力传播研究

Shale gas reservoir study of unstable pressure propagation

页岩气藏已经成为全球油气勘探的新亮点。由于页岩气藏特殊的地质特征和储层物性,页岩气藏不稳定的压力传播方式及影响规律并没有充分认识清楚。本文建立了考虑启动压力梯度和赋存状态的页岩气藏复合模型,利用非齐次虚宗贝塞尔函数进行页岩气藏复合模型井底压力数学模型的求解,分析页岩气藏不稳定压力传播的规律,研究了页岩气藏井储系数、解吸压缩系数、内区渗透率、表皮因子、启动压力梯度等因素的影响规律。结果表明,对于外区渗透率相对低的页岩气复合油藏中,解吸压缩系数、井储系数、内区渗透率和内区半径是敏感因素。

Shale gas reservoirs have become a new bright spot in the global oil and gas exploration .The geological characteristics and reservoir shale gas special pressure ,propagation and influence of shale gas reservoir is not stable and did not fully understand .In this paper ,considering starting pressure gradient and occurrence of shale gas reservoirs ,composite model ,by solving the non‐homogeneous virtual Bessel function of shale gas reservoirs ,complex mathematical model of bottom hole pressure model ,analyzes the shale gas unsteady pressure propagation law ,the influence of shale gas reservoirs in the area of wellbore storage coefficient ,permeability the permeability ,skin factor ,region ,starting pressure gradient ,desorption compression coefficient and gas production factors .Shale gas reservoir with low permeability of the composite region ,wellbore storage coefficient ,permeability ,permeability of inner zone region ,inner region radius and the desorption coefficient of compressibility is a sensitive factor .