Structural Evaluation, Using 2d Seismic Data Of Dhulian Area, Potwar, Pakistan

Abstract

Dhulian is located in the Central Potwar Zone and is broad east-west trending, doubly plunging anticline. The aim of the study is to identify structures present in the area of Dhulian through the interpretation of the Seismic data. A total number of 5 seismic lines PDK-101, PDK-103, PDK-104, PDK-112, and PDK-113, well logs of Dhulian-43, and a base map were provided to us by the Directorate General of Petroleum Concession (DGPC) from a Seismic survey conducted by O.G.D.C. in 1981 in the area of Dhulian. Four prominent reflectors R1 (Chorgali Formation), R2 (Sakesar Formation), R3 (Lockhart Formation), and R4 (Basement) are marked on the Seismic sections and mapped. Two-way travel time for each reflector was calculated and the average velocity for each line was calculated by using the Mean Line Method. Time and depth contour maps were made for the four horizons and then plotted on the computer software Rock Works to view time and depth surfaces. These contour maps show a faulted anticline subsurface structure favorable for hydrocarbon accumulation. Geoseismic sections, representing seismic structures in terms of depth were prepared for the lines PDK-104 and PDK-113 by using depth of horizons picked and formation thicknesses encountered in well Dhulian-43.