Structural identification and hydrocarbon evaluation followed by seismic attribute analysis using 2D seismic and well data of Balkassar area, upper Indus basin Pakistan (P-1094) (MFN 3918)

Abstract

Balkassar anticline. A 2-D seismic survey was carried out in 1981 to explore the deeper potential of the sedimentary sequence i.e. Khewra Sandstone of Early Cambrian age. The 2D seismic data, consisting of seismic lines PBJ-01, PBJ-02, PBJ-03, PBJ-04, PBJ-05, PBJ-06, PBJ-07 PBJ-08, PBJ-09, PBJ-10 and PBJ-11 and three wells, Balkassar Oxy-1, Balkassar-08 and Balkassar-07 are used in the study. Two dimensional seismic interpretations have been carried out in the upper Indus Basin, Balkassar area to map subsurface structure. Seismic interpretation is confirmed by 2-D seismic modeling. Crustal shortening is used to determine tectonic regime and to study the Eocene limestone’s accumulations in Balkassar Oil Field, and to examine how they were impacted by tectonics. Furthur seismic attribute analysis is carried out to identify prospect zone and to aid interpretation. Engineering properties evaluation is done using rock physics study. Confirmation of prospect zone is done by petro physical analysis. Lithology, porosity, water saturation and hydrocarbon saturation indicate two productive zones, Chorgali and sakesar zone. Average value of porosity ranges from 1 to 4% and 1-3%, water saturation from 4-7% and 3-4%, and hydrocarbon saturation from 4- 6% and 2-3% for Chorgali and Sakesar zone respectively.