Abstract:
Meyal oil field is one of the major oil and gas producing fields in the Potwar plateau
upper Indus basin, northern Punjab, Pakistan. The field was discovered by Pakistan
Oilfields Limited POL in 1968 after the seismic data acquisition. The field has produced
16 wells and has produced over 36 MMBL oil and 250 BCF gas from fractured
Paleocene and Eocene shallow marine shelf carbonate deposits of the Lockhart-
Ranikot and Chorgali-Sakesar formation. Most of the wells drilled in the central part of
the Eocene structure. The Himalayan Collision system represents an active collision
orogen between Indian and Eurasian subcontinents. The collision is active since about
55 Ma involves continuous uplifting, erosion and deposition of the sediments.
Data for the 2D seismic interpretation involves five seismic lines, three dip lines and two
strike lines were provided including Base map of the given seismic lines.
For the interpretation of seismic data three reflectors R1, R2, R3, have been marked
depending on prominent wiggles and named as, Chorgali formation, Nammal formation
and basement on the basis of given seismic lines. Faults were also marked to examine
the subsurface structure. A pop-up structure can be seen in the marked seismic section.
Time section is converted into the depth section to view the real picture of the
interpreted horizons. Time and depth contour maps of Chorgali and Nammal formations
are also prepared at a particular level to analyze the variations on the basis of time and
depth and for the identification of structures.
For calculation of average velocities, TWT is picked from the horizon and the RMS
velocity which is given above the seismic section in windows. The respective travel time
to their respective RMS is interpolated and then we obtain TWT and its respective
distance on excel sheet. The average velocity is calculated by taking the average of
respective RMS velocities and depth is obtained by multiplying the average velocity with
TWT.
