RESERVOIR QUALITY ANALYSIS OF EOCENE SEQUENCE CARBONATE USING WIRELINE LOG DATA IN DHURNAL OIL FIELD, UPPER INDUS BASIN PAKISTAN

Abstract

The Dhurnal oil field is located in the foreland belt of North Potwar Deformed Zone (NPDZ) of the Potwar sub-basin and one of the main and oldest hydrocarbon producing fields of the area. Dhurnal area lies in compressional regimes which result pop-up geometry between back-thrust and the fore-thrust. This research encompasses the petrophysical analysis using water saturation, resistivity of water, average porosity, saturation of hydrocarbon and volume of shales. The present research study is conducted on the Eocene Sakesar Formation for the detailed sequence stratigraphic interpretation and reservoir characterization in Dhurnal area. The obtained data for the petrophysical analysis and stratigraphic interpretation are in the form of Las file and well log data of Dhurnal-01 and Dhurnal-02 wells. Resistivity of water in the Sakesar Formation in Dhurnal-01 well ranges from 3.1% to 3.3% while in Dhurnal-02 well it ranges from 4% to 4.5% and the hydrocarbon saturation in Sakesar Formation in Dhurnal-01 well ranges from 72% to 75.5% whereas in Dhurnal-02 well ranges from 34.5% to 36.5%. The decrease in Gamma ray log values indicate high system tract (HST), which follow progradatinol geometry towards a regression base level. This pattern indicates shallow marine slope environment. Gamma ray log values fluctuate over short period of time in transgressive system tract (TST). In this short period of time the environment of deposition is Estuarine Shelf and Shallow Marine.