PetrophysicsElectrical Properties
Non-Ideal Shale Membrane Efficiency from Shale Resistivity Formula
Non-Ideal Shale Membrane Efficiency from Shale Resistivity calculates membrane efficiency for electrical properties workflows in petrophysics.
How engineers use this formula
Use this formula when the listed inputs (R_sh) are known and the assumptions behind the cited electrical 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, m_eff equals 0.92 fraction.
R_shohm m
1.5
Inputs
R_sh
ohm mShale Resistivity
Outputs
m_eff
fraction
Membrane Efficiency
R_sh
ohm m
Shale Resistivity
Source and review
reviewedTheory, Measurement, and Interpretation of Well Logs, Bassiouni, Z. (1994)
Bassiouni, Z. 1994. Theory, Measurement, and Interpretation of Well Logs. SPE Textbook Series Vol. 4, Chapter 6, Page 137.
Source