Petroleum resource assessment using reservoir volumetric approach relies on porosity and oil/gas saturation characterization by laboratory tests. In liquid-rich resource plays, the pore fluids are subject to phase changes and mass loss when a drilled core is brought to the surface due to volume expansion and evaporation. Further, these two closely related volumetric parameters are usually estimated separately with gas saturation inferred by compositional complementary law, resulting in a distorted gas to oil ratio under the circumstances of liquid hydrocarbon loss from sample. When applied to liquid-rich shale resource play, this can lead to overall under-estimation of resource volume, distorted gas and oil ratio (GOR), and understated resource heterogeneity in the shale reservoir. This article proposes an integrated mass balance approach for resource calculation in liquid-rich shale plays. The proposed method integrates bulk rock geochemical data with production and reservoir parameters to overcome the problems associated with laboratory characterization of the volumetric parameters by restoring the gaseous and light hydrocarbon loss due to volume expansion and evaporation in the sample. The method is applied to a Duvernay production well (14-16-62-21W5) in the Western Canada Sedimentary Basin (WCSB) to demonstrate its use in resource evaluation for a liquid-rich play. The results show that (a) by considering the phase behavior of reservoir fluids, the proposed method can be used to infer the quantity of the lost gaseous and light hydrocarbons; (b) by taking into account the lost gaseous and light hydrocarbons, the method generates an unbiased and representative resource potential; and (c) using the corrected oil and gas mass for the analyzed samples, the method produces a GOR estimate close to compositional characteristics of the produced hydrocarbons from initial production in 14-16-62-21W5 well.

使用储层体积法进行的石油资源评估依赖于通过实验室测试进行的孔隙度和油气饱和度表征。在富含液体的资源中，当由于体积膨胀和蒸发将钻好的岩芯带到地面时，孔隙流体会发生相变和质量损失。此外，这两个密切相关的体积参数通常是根据组成互补定律推断出的气体饱和度单独估算的，从而导致在样品中液态烃损失的情况下，气油比发生了失真。当将其用于富含液体的页岩资源时，可能会导致整体上低估资源量，扭曲的油气比（GOR）以及低估页岩储层中的资源非均质性。本文提出了一种用于在富含液体的页岩气中进行资源计算的综合质量平衡方法。所提出的方法将大块岩石地球化学数据与生产和储层参数相结合，以通过恢复由于样品中体积膨胀和蒸发引起的气态和轻烃损失来克服与体积参数的实验室表征有关的问题。该方法已应用于加拿大西部沉积盆地（WCSB）的Duvernay生产井（14-16-62-21W5），以证明其在资源评估中用于富液油田。结果表明：（a）通过考虑储层流体的相态特性，该方法可用于推断气态和轻烃损失的数量；（b）考虑到损失的气态和轻烃，该方法产生无偏的和代表性的资源潜力；（c）对分析后的样品使用校正后的油气质量，该方法将产生GOR估算值，该估算值接近于14-16-62-21W5井初次生产时所生产的烃的成分特征。