Reservoir EngineeringPressure Transient Analysis
Cole Plot Formula
Cole Plot calculates underground water withdrawal for pressure transient analysis workflows in reservoir engineering.
How engineers use this formula
Use this formula when the listed inputs (G, E_g, W_e) are known and the assumptions behind the cited pressure transient analysis relationship match the engineering case being checked.
Assumptions
- Input values are representative for the well, reservoir, fluid, or equipment case being evaluated.
- The declared units match the field-unit constants used in the formula.
- The cited formula applies to the selected petroleum engineering workflow.
Limitations
- The calculation does not replace a full engineering model or operating procedure.
- Accuracy depends on the source correlation, assumptions, input quality, and unit consistency.
Common mistakes
- Mixing unit systems without converting the inputs.
- Using default example values as field recommendations.
- Applying the formula outside the source assumptions.
Default example
Using the default inputs, F equals 105 bbl.
GMSCF
1000
E_gbbl/MSCF
0.005
W_ebbl
100
Inputs
G
MSCFCumulative Gas Production
E_g
bbl/MSCFGas Expansion Factor
W_e
bblCumulative Water Influx
Outputs
F
bbl
Underground Water Withdrawal
G
MSCF
Cumulative Gas Production (rearranged)
E_g
bbl/MSCF
Gas Expansion Factor (rearranged)
W_e
bbl
Cumulative Water Influx (rearranged)
Source and review
reviewedAhmed, T., McKinney, P.D. Advanced Reservoir Engineering, Gulf Publishing House, Burlington, MA, 2015.
Source