<p>The Lower Goru Formation is the main hydrocarbon target in Middle Indus basin, Pakistan. Its variable reservoir sand intervals complicate facies estimation for optimal production and allow for the investigation of how depositional and diagenetic changes affect reservoir quality in complex stratigraphic traps. We utilized an integrated approach to analyze the main E-sand interval with well log data, seismic data, thin-section petrography, SEM, and XRD analysis, revealing its geological features, depositional environment, spatial distribution, and reservoir quality. This study identifies nine distinct lithofacies with in the Cretaceous lower Goru formation: Massive Sandstone, Bioturbated Sandstone, Parallel Laminated Sandstone, Cross Laminated Sandstone, Massive Mudstone, Sandstone and Mudstone Intercalations, shaly sandstone, Brecciated Sandstone, and shale. Categorized into three primary depositional settings: foreshore, shoreface, and backshore. The findings provide crucial insights into the depositional history and reservoir quality, particularly in the basal sand units that transitions from fluvial to tidal, then to a deltaic front, and finally to a shallow marine setting. The reservoir sand intervals are primarily classified as “subfeldsarenite” to “sublithicarenite”, formed in a recycled orogenic environment. The main diagenetic processes include compaction, carbonate cementation, and the formation of authigenic chlorite and quartz overgrowths, which later significantly influencing reservoir quality. Facies analysis identified clean sand and mixed sand-shale reservoir zones, while petrophysical analysis indicated a net pay of 5 m in the E-sand and Hydrocarbon saturation of about 61%. Scanning Electron Microscopy (SEM) provided insights into pore structure and mineral composition. These findings, along with core plug porosity and permeability measurements, suggest favorable reservoir characteristics. A random forest algorithm was used to extract elastic and petrophysical attributes from seismic and well data, aiding in the development of a petro-elastic relationship and identifying potential gas zones. This study enhances the understanding of how depositional facies and diagenesis affect reservoir quality and highlights that the massive sandstone have superior properties compared to the basal sand.</p>