Petrophysical characterization and reservoir potential of the Lower Goru sandstone: A case study from the Sinjhoro Gas Field, Pakistan

Abstract

The primary method which has been traditionally used for assessing the hydrocarbon potential of reservoir rock involves analyzing petrophysical properties via well logs. Evaluating these properties is crucial for introducing new perspectives. This study offers a valuable case study for regional hydrocarbon evaluation, providing practical insights for exploration in the Lower Indus Basin, Pakistan. This study presents a comprehensive petrophysical evaluation of the Lower Goru Formation (LGF) located in the Sinjhoro Gas Field of Sindh, Pakistan. The characteristics of LGF reservoir are outlined, hydrocarbon potential is evaluated, and gas productivity is quantified through the analysis of density, gamma-ray, resistivity, and neutron logs, along with lateral correlation among different wells. Six significant sand masses exist that may be utilized for hydrocarbon extraction. The extensive sand area serves as the main contributor to current output from wells such as Hakeem Daho-01 and Resham-01, whereas the basal sand is the key source of production for the Well Chak-5. This study underscored the importance of leveraging these resources by showcasing the substantial hydrocarbon potential of the basal sand in Resham-01 and the extensive sand-01 in Hakeem Daho. The massive sand-01 exhibits a thickness of 10 m, with a hydrocarbon saturation of 72%, an average porosity of 11%, a shale volume of 18%, and a net thickness of 8 m. In contrast, the basal sand shows a hydrocarbon saturation of 62%, a porosity of 12%, and a net thickness of 8 m. Both are considered to possess significant reservoir potential. The data shown here has been correlated with its nearby stratigraphic equivalents dealing with the Bhuj Formation of the Kachchh Basin on India's western margin, which is important to understand and predict reservoir properties in other sandstone petroleum fields with similar properties. The conclusions of the study address issues related to reservoir characterization and facilitate the production and utilization of the significant hydrocarbon resources found in the Sinjhoro Gas Field.