Reservoir EngineeringMaterial Balance and Production
Produced Gas-Oil Ratio Formula
Produced Gas-Oil Ratio calculates net cumulative produced gas-oil ratio for material balance and production workflows in reservoir engineering.
How engineers use this formula
Use this formula when the listed inputs (G_p, N_p) are known and the assumptions behind the cited material balance and production 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, R_p equals 900 SCF/STB.
G_pSCF
180000000
N_pSTB
200000
Inputs
G_p
SCFCumulative Gas Production
N_p
STBCumulative Oil Production
Outputs
R_p
SCF/STB
Net Cumulative Produced Gas-Oil Ratio
G_p
SCF
Cumulative Gas Production
N_p
STB
Cumulative Oil Production
Source and review
reviewedAdvanced Reservoir Engineering, Ahmed, T., McKinney, P. D. (2005)
Ahmed, T. and McKinney, P. D. 2005. Advanced Reservoir Engineering, Gulf Publishing of Elsevier, Chapter 4, Page 302.
Source