PetrophysicsResistivity Logs
Compacted Carbonate Formation Factor from Porosity Formula
Compacted Carbonate Formation Factor from Porosity calculates formation resistivity factor for compact rocks for resistivity logs workflows in petrophysics.
How engineers use this formula
Use this formula when the listed inputs (phi, a) are known and the assumptions behind the cited resistivity logs 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_cO equals 40.516415 dimensionless.
phifraction
0.2
adimensionless
2.3
Inputs
phi
fractionPorosity
a
dimensionlessCarbonate Cementation Exponent Constant
Outputs
F_cO
dimensionless
Formation Resistivity Factor for Compact Rocks
phi
fraction
Porosity
a
dimensionless
Carbonate Cementation Exponent Constant
Source and review
reviewedBassiouni, Z. 1994. Theory, Measurement, and Interpretation of Well Logs, SPE Textbook Series Vol. 4, Chapter 1, Page 10.
Source