Abstract:
This dissertation comprises the study of 2D seismic reflection for the
demarcation of subsurface structures for the hydrocarbon accumulation in Gulyana
area, Upper Indus Basin, Pakistan. The provided data comprised of five seismic lines.
Four conspicuous reflectors representing Sakesar, Chorgali, Dandot and Khewra
formations were marked on basis of their reflections. The interpreted structure was NESW
trending pop-up anticline bounded with two NW dipping major thrust faults and
one minor SE trending back thrust. Time, velocity and depth contour maps confirm the
presence of pop-up structure and bounding thrust faults. Petrophysical interpretation
for Qazian X-01 indicated a prospective zone in Sakesar Limestone which is mainly
water wet with the average water saturation of about 81.7%. The rock physics
modelling has reassured the presence of hydrocarbons in the Gulyana area. The new
wellsite is also suggested on the line 994-GNA-14 because of abrupt decrease in Vp/Vs,
Poisson’s ratio and density as compared to line 994-GNA-09 on which the Qazian X-
01 was drilled. The volumetric estimates for the Sakesar Limestone done on the basis
of Petrophysics and seismic interpretation suggest that there is about 9.84 million
barrels of oil at reservoir conditions.
