Structural Interpretation of Western margin of Tanwin Bains Anticline, Eastern Potwar sub-basin, Pakistan

Abstract

Upper Indus Basin has been a valuable area as the complexity of structure and hydrocarbon production is the leading producer for oil and gas in history and still to date. Potwar Sub-Basin of Eastern Potwar has significance in the light of oil production from carbonate reservoirs or Eocene, Permian and Cambrian age reservoirs. The complexity is present for carbonate reservoirs of Eocene (Chorgali, Sakesar, and Lockhart formations) due to significant tectonic deformation and facies variation. Researchers suggested advanced methods for further hydrocarbon potential evaluation, but so far no detailed work has been done to conclude it. Apart from all the above difficulties, Eastern Potwar fields are the leading producers for hydrocarbon production. Tanwin Bains Anticline present in Eastern Potwar is surrounded by many producing fields as Turkwal, Fimkassar, Adhi and Chaknaurang etc. Tanwin Bains Anticline is a surface anticline which has unique hydrocarbon production history with complexity in stratigraphy and structure. This research's primary focus to analyze structural geometry of the research area by conventional seismic interpretation. And to look into the tectonic activity of the region that is associated with faulting and salt mobilization which has caused the structural evolution of Eastern Potwar sub-basin. The deformation has taken place due to increased basal traction, the anticlines are tight while the synclines are broad, faults cut up section to produce a complex structural geometry. 2D seismic data interpretation helps to understand the subsurface structural geometry of Tanwin Bains Anticline which consists of thrusts and back thrusts, forming triangle zones and Pop-up structures. Advanced exploration techniques have to be carried out to get a better image of the subsurface and understand the complex tectonic activity of the area. Furthermore, a balanced cross section is created and structural restoration has been done to know the crustal shortening of the area and to understand the subsurface structural geometry and severe deformation that has taken place in the geological time frame.