Dictionary:Percent frequency effect (PFE)
1. The basic polarization parameter measured in frequency-domain resistivity surveys, being the percent difference in apparent resistivity measured at two frequencies:
where and are the low- and high-frequency apparent resistivities.
2. Decade-normalized PFE is multiplied by the log of the frequency ratio:
3. Keller suggests that PFE be defined as:
where ρ1 and ρ2 are apparent resistivities measured at two frequencies that are a factor of 10 apart.