SDR NMR Permeability from T2 Geometric Mean Formula
SDR NMR Permeability from T2 Geometric Mean calculates nmr-derived permeability by sdr model for rock properties workflows in petrophysics.
How engineers use this formula
Use this formula when the listed inputs (a_SDR, phi_NMR, T2gm) are known and the assumptions behind the cited rock properties 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, k_SDR equals 59.969536 mD.
4
0.22
80
Inputs
a_SDR
mD/ms^2SDR Empirical Permeability Coefficient
phi_NMR
fractionNMR Porosity
T2gm
msT2 Distribution Geometric Mean
Outputs
k_SDR
NMR-Derived Permeability by SDR Model
a_SDR
SDR Empirical Permeability Coefficient
phi_NMR
NMR Porosity
T2gm
T2 Distribution Geometric Mean
Source and review
reviewedNMR Logging Principles and Applications, Coates, G.R., Xiao, L., Prammer, M.G. (1999)
Coates, G.R., Xiao, L., and Prammer, M.G. 1999. NMR Logging Principles and Applications. Halliburton Energy Services, MPERM glossary entry.
Source