Moderate Interpretation with Attribute Analysis and 3d Visualization for Deeper Prospects of Balkassar Field, Central Potwar, Upper Indus Basin, Pakistan

Abstract

Balkassar is an old field with considerable remaining potential. The 2d, 3d seismic and earlier vintages show that Balkassar is composed of two folds that impart heart shaped geometry. It appears likely the early Eocene age Bhadrar formation may provide commercial production with lower water cuts from the eastern lobe (yet untapped) of the structure that may have at least 30 million barrels of unrecovered oil. Horizontal drilling may have promise as an optimum technique for recovery of oil from Paleogene reservoirs. Encouraging oil indications have also been recorded from the early Permian age tobra formation from Balkassar oxy-1 that was not tested by Oxy. Tobra sandstone reservoir can have a matrix porosity approaching 8%. When fractured recoveries from it can be relatively better than the Paleogene reservoirs. The 2D and 3D seismic acquisition has confirmed that the eastern lobe (yet untapped) of the Balkassar field is structurally higher and steeper than the Western lobe which has thus far produced over 30 million barrels. The Eastern lobe thus offers good potential for recovery of oil from the Bhadrar reservoir. The entire field is likely to have potential for recovery of oil from the early Eocene aged Tobra formation. 2-d and 3-D Seismic data interpretation, attribute analysis and visualization for deeper prospect carried in Balksasar field. Tobra and Khewra formation studied for deeper potential drilling. Time contour and depth contour map shows potential for deeper prospects. Also attribute analysis and 3d visualization show good results for deeper potential of Tobra and Khewar formations. Seismic amplitude, Reflection strength, Apparent polarity attribute are visualized and interpreted to find the potential for Tobra and Khewra formation. 3-D visualization also showed positive results for Tobra and Khewra formations.