Sedimentology and Sequence Stratigraphy of the Late Permian Wargal Limestone: Implication for Reservoir Potential in the Salt Range, Pakistan

Abstract

The present work comprehensively highlights the Late Permian Wargal limestone exposed in the western Salt Range, Pakistan. The purpose of this study is to determine its hydrocarbon with the help of sedimentology and sequence stratigraphy. The outcrop data classified the studied formation into nine lithological units in the Nammal Gorge, Gundi, and Lakrakki Nala sections. Our sequence stratigraphic interpretation reveals that the Wargal Limestone consists of four depositional sequences. These sequences consist of regressive system tract and tansgressive system tract that developed during relative sea-level fall and rise, respectively. Based on contents of fossils, quratz grains and matrix, the studied formation can be classified into six microfacies that suggests the deposition of the carbonate facies thrived in inner to middle shelf environment. Moreover, microfacies comprises of numerous diagenetic features that support the potential of hydrocarbon content. In addition, X-ray diffraction analysis (XRD) data suggests that the main composition of the Wargal Limestone is calcite. Consequently, the integrated results of the sedimentology, sequence stratigraphy, and geochemical analysis provide the credible evidences of its significance in exploration industry.