2D seismic reflection data interpretation of Meyal area, integrated petrophysical analysis along seismic attribute analysis

Abstract

The present study pertains to the two dimensional seismic interpretation, attributes analysis and petrophysical analysis. The data used for this study consists of SEG - Y data and well logs data of Meyal area provided by the Department of Earth Sciences Quaid-i-Azam University Islamabad. Meyal area lies in the Potwar sub basin which is in the northern part of Upper Indus basin. Meyal area is bounded in the north by main Boundary Thrust (MBT) and Salt Range in the south, Thelum strike-slip fault occurs in the east and Indus River and Kalabagh strike slip fault in the west and is known for its hydrocarbon (oil and gas) structural traps. The Seismic lines were acquired and processed by Pakistan oilfield limited (POL). For interpretation of these seismic lines three reflectors i.e. Chorgali, Sakessar, Nammal and reverse faults are marked by using the interactive tools of Kingdom software. In this way time sections obtained. After time to depth conversion the true structural geometry is obtained in the form of depth sections. The marked horizons were identified using formation tops from wells. After that fault polygons, time grids and depth grids of marked horizons were prepared. From time and depth grids, the time and depth contour maps of the horizons of interest were generated to understand the spatial geometry of the structures and the nature of geological structures as identified by the seismic section of the area. Reverse faulting confirmed compressional tectonic regime in the study area resulting due to Indian Eurasian plate's collision. The resulted seismic interpretation of these lines showed pop-up structures and snaked head bounded by reverse faulting. These pop-up structures were favorable places for hydrocarbons accumulation and extraction. Seismic attributes analysis of seismic sections helps in identifying the different lithological boundaries and further confirmed the structural and stratigraphic interpretation and petroleum play of the study area. The Petrophysical analysis of the line of Meyal-07 for the selected zones of interest showed reservoir quality of different formations.