Seismic interpretation, petrophysical log analysis, velocity interpolation and modeling of Missa Keswal, Potwar sub-basin (T-1472) (MFN 3887)

Abstract

The present study pertains to the modeling of the productive zones from seismic and well log data. This was carried out by seismic lines 926-GJN-15, 926- GJN-16, 932-GJN-20, 932-GJN-26 and well log data (LAS format) of Missa Keswal 03 provided by the Directorate General of Petroleum Concession. The area is a part of Potwar sub-basin. The methodology adopted to accomplish this task includes; structural interpretation of seismic data, 2-D seismic modeling, crustal shortening, synthetic seismogram, petrophysical analysis and velocity modeling. Seismic data analysis includes identification and marking of different lithological horizons and names them according to the depths after correlation with well data. Seismic structural model show major thrust faults which confirm the compressional tectonic regime in the study area. Depth and time contour maps along with velocity maps revealed the potential zones of hydrocarbon in the area which were marked and confirmed with the help of seismic data interpretation. The crustal shortening calculated on the seismic sections of the area under study shows that the crust has shortened over the period of time. The petrophysical analysis is done by determining porosity, water saturation, volume of shale, resistivity of water and hydrocarbon content for the selected zones; the results show good reservoir quality. The velocity models indicate the importance of lateral velocity variations. After the time to depth conversion, the reflectors are smoothened out with the help of spatial and temporal corrections and the depth section can then be used for further seismic data analysis. The processed velocity model shows better results for further analysis on structure evaluation and decision making.