2D STRUCTURAL INTERPRETATION AND SEISMIC ATTRIBUTE ANALYSIS OF SAWAN AREA, LOWER INDUS BASIN, PAKISTAN

Abstract

The purpose of this research is to delineate the subsurface structure of area and investigation of fluid properties through well logs, to understand and clarify the hydrocarbon prone areas through seismic attributes analysis to justify the drilling location. First, the acquired data was matched with interpretation datum. Structural analysis was done by performing the horizon interpretation, the fault interpretation, and contour mapping on C-Interval of Lower Goru Formation. The hydrocarbon zones were marked with the help of attribute analysis on seismic sections and were justified by petrophysical analysis of acquired wells. This research showed that Normal faults are present in the area showing negative flower structure, horst and graben, faults orientation is north-west to south-east. Contour map shows structural inclination and faults bounded closure near well locations. It was further clarified by applying fault seal analysis on contour maps that the faults are making a suitable closure. Variance and spectral decomposition attribute were used to verify horizon lineation and faults behavior. Instantaneous frequency, instantaneous phase attributes justify hydrocarbon bearing zones. Bright spots are identified at C-Interval of Lower Goru Formation. Petrophysical analysis of the given wells showed more than 55 percent of hydrocarbon saturation at C-Interval of Lower Goru member. The four possible reservoir zones in Sawan-02 well and two zones in Sawan-07 well and three zones in Sawan-09 well are identified on the basis of seismic and well data interpretation. Thus, the area of interest has very good reservoir potential with good permeability, structural closure, and visible bright spots in it.