Abstract: A new method for estimating the original gas in place(OGIP) of over-pressured gas reservoir with aquifer was proposed.This method is based on the generalized material balance principle and can be used to calculate the volume expansion terms of reservoir rock in the individual stage of pressure drop by the experimental results of reservoir rocks under supper high pressure.Considered rock deformation and natural water influx into over-pressured reservoirs,a modified material balance equation was derived by the connate water expansion equation and unsteady state water influx equation.A trial and error procedure were applied to solve this new equation.The case analysis and comparison show that this new method is reliable and effective for predicting OGIP of over-pressured reservoir with aquifer.

Key words: over pressured gas reservoir, rock deformation, water influx, material balance equation, original gas in place, calculation method

摘要： 提出了一种计算异常高压有水气藏地质储量的新方法.此方法是在广义物质平衡原理的基础上,根据岩石覆压试验的数据处理结果,计算出气藏各个压降阶段对应的气藏岩石骨架体积膨胀量.根据气藏各个压降阶段气藏束缚水体积膨胀方程和不稳定水侵方程,推导出考虑岩石变形及自然水侵的异常高压有水气藏物质平衡方程,并通过试算法给出了方程的解.通过实例分析与对比论证了此方法的可靠性、有效性.

关键词: 异常高压气藏, 岩石变形, 水侵, 物质平衡方程, 地质储量, 计算方法