2D Seismic Interpretation and Petro physical Analysis of FIM Kasar Area, Upper Indus Basin, Pakistan

Abstract

In the eastern part of the Potwar Sub-basin lies the Fim Kassar area, which is a leading structural division of the Upper Indus Basin of Pakistan.The Potwar Basin is a hydrocarbon-producing area. Because of compressional tectonism, the subsurface structural layout permits the oil and gas to trap in a larger amount. The study aims for the seismic interpretation and petrophysical analysis of Fim Kasar area. We performed 2D Seismic Interpretation of the Fim Kassar Region, combining Petrophysical Analysis with Seismic Interpretation, the correlation of Well Data with seismic data and delineating prospects. Fim Kassar area is situated in the Upper Indus Basin of Pakistan, mostly comprises of clastic rocks such as sandstones, shales, and conglomerates, along with well-developed carbonate units, particularly the Lockhart Limestone. The upper Indus basin consists of thick Infra- Cambrian evaporites, thin calcareous-siliciclastic sediments on Indian Plate and in Indus Foredeep broad molasse deposits. In Potwar basin, by the analysis of seismic profiles results concluded two decollement units showing lower unit present in Salt Range Formation and the upper unit at the boundary of Eocene and Neogene molasse sediments. The shales present in Patala Formation of age Eocene-Paleocene are source, Chorgali and Sakesar Limestone of age (Eocene) is a reservoir, and clays and shales act as a seal over these reservoirs. Data was obtained through the approval of Director General Petroleum Concessions (DGPC), Petroleum House. The data includes five seismic lines (dip, strike and crooked line) and one well (turkwal-01) on which petrophysical analysis and horizon demarcation. In seismic, popup structures are delineated on seismic sections, and this structure is also depicted by time and depth contour maps. The velocities used in depth contour maps are well velocities. In petrophysical analysis, volume of shale is 27.8%, hydrocarbon saturation is 55.6% and porosity (Average 12.2% & Effective 7.94%) for Chorgali Formation, for Sakesar Formation volume of shale is 25%, hydrocarbon saturation is 75%, and porosity (Average 2.2% & Effective 1.1%). These results proved that Chorgali formation was economically more viable compared to Sakesar Formation.