Document Type : Original Article

Authors

1 Department of Geology, Hazara University Mansehra KPK, Pakistan

2 Institute of Geology, University of the Punjab, Lahore, Pakistan

3 Department of Geology, Abdul Wali Khan University Mardan KPK, Pakistan

Abstract

Eastern Suleiman Fold and Thrust Belt comprise a thick cover of sedimentary sequences. Complete petroleum system source, reservoir, and seal rocks are present in these sequences. An integrated approach is adopted to delineate reservoir potential and net pay zones in the clastic reservoirs of the Cretaceous age widely distributed in the area. Wireline logs and migrated seismic reflection data were used for field development and optimization. Petrophysical analysis reveals that Pab Sandstone of the Cretaceous age is acting as reservoir rock, whereas the Ghazij Shales of the Eocene age are acting as a regional seal rock. A complete workflow is proposed for formation evaluation and structural interpretation of the subsurface geology. Based on wireline logs it is interpreted that the thickness of the Pab Sandstone varies from 250 m to 350 m in the entire study area. The sandstone is massive with high porosity and intercalated layers of shales. Faulted anticlinal structures are present in the study area which are favorable for the accumulation of hydrocarbon. 3D structural models and various seismic attribute models were prepared to analyze the reservoir character of this clastic reservoir. Based on wireline logs and seismic data clean sand, shaly sand, and shale are marked as dominant facies in the study area. However, clean sand facies are more favorable to act as potential net pay zone.

Keywords