岩石压缩系数对气藏动态储量计算的影响

Effect of Rock Compressibility on Gas Reservoir Reserve Determination

气藏动态地质储量的计算结果受生产数据、气藏测压数据以及岩石和流体物性等参数的影响。目前确定岩石压缩系数的方法主要有实验测量法和Hall图版经验公式法,由于Hall图版由实验值统计而来,因而这二种方法基本上是一致的。用Hall图版确定的岩石压缩系数明显偏高,且Hall图版错误地显示了岩石压缩系数与孔隙度的逻辑关系,因而都是一些错误的数值。用笔者提出的岩石压缩系数与孔隙度的关系曲线确定的岩石压缩系数一般都较低。本文算例表明,用Hall图版或实验确定的压缩系数计算的气藏地质储量明显偏小。

A gas reservoir reserve determination is affected by the production data, reservoir pressure and property parameters of reservoir rock and fluid. The rock compressibility is mostly determined by lab measurement and Hall empirical equation that can be obtained from core analysis data. However, the Hall curve shows a wrong logic relation and provides abnormally high values of rock compressibility. With the new curve proposed by LI Chuan-liang, the rock compressibility usually appears low values in the porosity range of gas reservoir. This study indicated that the original gas in-place value calculated with the rock compressibility given by Hall curve or lab analysis will be underestimated obviously.