Abstract:
This dissertation represents the 2D seismic interpretation and petrophysical analysis in order to delineate the subsurface structure and hydrocarbon potential of the well Balkassar-OXY-01. It is considered a mature oilfield located in central part of Potwar Sub-basin which is a part of Himalayan foreland fold and thrust belt. The deformation is mainly in NW-SE direction. Four of the prominent reflectors are Chorgali Formation, Sakesar Limestone, Khewra Sandstone and Salt Range Formation marked on the seismic section on the basis of time-depth chart and well tops. Petroleum trap is a structural trap where major thrust and back thrust bound the anticline, and sealing impact is provided by both clays of Murree Formation and faults which is further confirmed by fault seal analysis (Allan diagram). Among the two horizons, Sakesar and Chorgali, of Eocene package, Chorgali is the reservoir formation of an area. For petrophysical analysis one zone has been marked at the level of Chorgali Formation which indicates effective porosity is 3.08%, 40.5% water saturation and 59.5% hydrocarbon saturation. Based on the statistical analysis performed, it can be concluded that the Chorgali Formation of Eocene age encountered in Balkassar area is a promising reservoir. The Patala Shale of Paleocene age act as the source rock in the study area while Murree Formation of Miocene age is acting as a seal. Volumetric Estimation is done to estimate the volume of original oil in place (OOIP) for the Chorgali Formation.
