The integrated study of seismic attributes and inversion analysis can provide a better understanding for predicting the hydrocarbon-bearing zones even in extreme heterogeneous reservoirs. This study aims to delineate and characterize the gas saturated zone within the reservoir (Cretaceous C-sand) interval of Sawan gas field, Middle Indus Basin, Pakistan. The hydrocarbon bearing zone is well identified through the seismic attribute analysis along a sand channel. The sparse-spike inversion analysis has efficiently captured the variations in reservoir parameter (P-impedance) for gas prospect. Inversion results indicated that the relatively lower P-impedance values are encountered along the predicted sand channel. To further characterize the reservoir, geostatistical techniques comprising multiattribute regression and probabilistic neural network (PNN) analysis are applied to predict the effective porosity of reservoir. Comparatively, the PNN analysis predicted the targeted property more efficiently and applied its estimations on entire seismic volume. Furthermore, the geostatistical estimations of PNN analysis significantly predicted the gas-bearing zones and confirmed the sand channel as a major contributor of gas accumulation in the area. These estimates are in appropriate agreement with each other, and the workflow adopted here can be applied to various South Asian regions and in other parts of the world for improved characterization of gas reservoirs.

中文翻译：

---

巴基斯坦中部盆地下古鲁组储层C砂层段天然气资源潜力预测

地震属性和反演分析的综合研究可以提供更好的理解，即使在非均质油藏中也能预测含烃带。这项研究的目的是描绘和表征巴基斯坦中部印度洋盆地萨万气田储层（白垩纪C砂）区间内的天然气饱和带。通过沿砂质通道的地震属性分析，可以很好地识别含烃带。稀疏峰反演分析已有效地捕获了天然气前景的储层参数（P阻抗）的变化。反演结果表明，沿预测的沙质通道遇到了相对较低的P阻抗值。为了进一步表征储层，包括多属性回归和概率神经网络（PNN）分析在内的地统计学技术可用于预测储层的有效孔隙度。相比之下，PNN分析可以更有效地预测目标属性，并将其估计值应用于整个地震体。此外，PNN分析的地统计学估计显着预测了含气区，并确认了砂质通道是该地区天然气成藏的主要贡献者。这些估算值彼此适当吻合，此处采用的工作流程可应用于南亚各个地区以及世界其他地区，以改善气藏的特征。PNN分析可以更有效地预测目标属性，并将其估计值应用于整个地震体。此外，PNN分析的地统计学估计显着预测了含气区，并确认了砂质通道是该地区天然气成藏的主要贡献者。这些估算值彼此适当吻合，此处采用的工作流程可应用于南亚各个地区以及世界其他地区，以改善气藏的特征。PNN分析可以更有效地预测目标属性，并将其估计值应用于整个地震体。此外，PNN分析的地统计学估计显着预测了含气区，并确认了砂质通道是该地区天然气成藏的主要贡献者。这些估算值彼此适当吻合，此处采用的工作流程可应用于南亚各个地区以及世界其他地区，以改善气藏的特征。