Problem 1
The production data for a gas field are given below. Assume volumetric behavior and calculate the following:
(a) Determine the initial gas in place.
(b) What percentage of the initial gas in place will be recovered at a p/z of 1000?
(c) The field is to be used as gas storage reservoir into which gas is injected during summer months and produced during the peak demand months of the winter. What is the minimum p/z value that the reservoir needs to be brought back up to if the supply of 50 MMM SCF of gas is required and the abandonment p/z is 1000?
Problem 2
A dry gas reservoir contains gas of the following composition:
The initial reservoir pressure was 4200 psia, with a temperature of 180°F. The reservoir has been producing for some time. Two pressure surveys have been made at different times.
(a) What will be the cumulative gas produced when the average reservoir pressure has dropped to 2000 psia.
(b) Assuming that the reservoir rock has a porosity of 12%, the water saturation is 30%, and the reservoir thickness is 15 ft, how many acres does the reservoir cover?
