Abstract:
This dissertation contains the study of 2D seismic reflection data interpretation of selected seismic lines of Chak Naurang, Northern Indus Basin, Pakistan, for delineation of subsurface structures favorable for hydrocarbon accumulation. Chak Naurang is situated in the Chakwal district of Punjab province. The data comprised eight seismic lines, base map, and well tops of well Chak Naurang 01. Two prominent reflectors (yellow and blue) were marked on the basis of their reflection, which represent Sakesar/Chorgali Formation and Khewra Formation respectively. Reflectors were identified with the help of well top data, after conversion of time to depth with the help of average velocity. Two-way time (TWT) from the seismic sections and average velocities were used to create TWT and Depth Contour maps and 3D Time and Depth Surfaces of Sakesar and Khewra. In the end, by the examination of the maps and surface models, more study of the area is suggested especially on the down thrown side, and for Khewra Formation. Asymmetrical anticlinal structure, cut by a NW dipping thrust fault was observed from the 3D time and depth surfaces of both Sakesar and Khewra Formation. The age of Sakesar Formation is Eocene and lithologically it consists of nodular limestone, while Khewra Formation is of Cambrian age and lithologically consists of sandstone. Both formations are possible reservoirs and also provide the required entrapment mechanism for hydro carbons which was observed by the time and depth surface maps of the formations. The up thrown side has already been drilled, but more study should be made on the down thrown side.
