2D SEISMIC DATA INTERPRETATION & FACIES ANALYSIS OF CHORGALI AND SAKESAR FORMATIONS, GUJAR KHAN AREA POTWAR SUB BASIN PAKISTAN

Abstract

The present study pertains to the interpretation, analysis and modeling of the productive zones for hydrocarbons from seismic and well log data. This was carried out by using SEG-Y seismic data of the lines GJN-09, GJN-11 and well log data (LAS format) of Rajian-01 well provided by the Directorate General of Petroleum Concession (DGPC). The area is a part of Potwar sub-basin. The area is important for its hydrocarbon (oil and gas) structural traps. Rajian oil field is located at the distance of 60 km in the South-East of Islamabad. The field was discovered in 1994 by OGDCL and came on regular production from 1994 till date. The seismic interpretation of the study lines shows anticlinal structures bounded by thrust faults. The horizons were identified using formation tops from wells. Time and depth contour maps of the horizons of interest have been generated to understand the spatial geometry of the structures. Seismic structural model shows major thrust faults, which confirm the compressional tectonic regime in the study area. Analysis of Chorgali and Sakesar formations (which are the reservoirs in the study area) in terms of their facies was done by using density, resistivity and gamma ray logs run in Rajian-01 well and keeping in view the response from these logs, different facies present in these formations were identified.