Gas Portion Entry Rate from Rock Removal Formula
Gas Portion Entry Rate from Rock Removal calculates gas-bearing pore-volume entry rate with drilled rock for drilling operations and economics workflows in drilling engineering.
How engineers use this formula
Use this formula when the listed inputs (q_r, phi, S_g) are known and the assumptions behind the cited drilling operations and economics 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, q_g equals 0.022989 ft^3/min.
0.32840909090909093
0.2
0.35
Inputs
q_r
ft^3/minBulk rock removal rate
phi
fractionFormation porosity
S_g
fractionGas saturation
Outputs
q_g
Gas-bearing pore-volume entry rate with drilled rock
q_r
Bulk rock removal rate
phi
Formation porosity
S_g
Gas saturation
Source and review
reviewedAdvanced Well Control, Watson, D., Brittenham, T., Moore, P.L. (2003)
Watson, D., Brittenham, T., and Moore, P.L. 2003. Advanced Well Control, Vol. 10, Society of Petroleum Engineers, Page 19.