Abstract:
The study area is located in Potwar plateau bounded by Main Boundary Thrust in
the north and Salt Range Thrust in south; whereas left lateral Jhelum fault in the east and
western boundary of the plateau marked by the right lateral Kalabagh fault. Potwar
plateau is the result of compressional tectonics at the northern margin of the Indian plate
by continent-continent collision between Indian and Eurasian plates in Tertiary time
period. The purpose of the study is to understand geological setting of the area and to
execute the petrophysical analysis to evaluate the reservoir rocks of Turkwal Deep-1 and
Turkwal Deep-X2 wells of Potwar plateau. Turkwal Deep-1 is exploratory well is drilled
into Sakesar Limestone of Eocene age and in that well the subthrusted sheet is penetrated
but the hydrocarbon potential of lower sheet remain untested. The area constitutes thick
deposit of sandstone from Cambrian to Cretaceous and thick carbonate deposits from
Paleocene to Eocene time period. The carbonates of Chorgali Formation and Sakesar
Limestone comprise important oil and gas producing reservoirs in the Potwar plateau. In
present study an attempt has been made to understand the development of fractures within
the carbonate of the formations. The carbonates are mostly tight in the outcrop, however
pore spaces observed in surface and subsurface of the area. These open pores are secondary
in origin and almost occur within carbonates. The major constituent that improves the
porosity and permeability is the fracturing of carbonates of the formation. The fracturing in
carbonates are the results of intense structural deformation in the Potwar plateau. This is the
reason that Chorgali and Sakesar carbonates are producing oil and gas in this part of the
Potwar plateau.
