1. n. [Formation Evaluation]

The resistivity of the formation derived by combining the attenuation and phase shift of a propagation resistivity measurement. Common practice is to transform attenuation and phase shift independently to resistivity, assuming a certain transform between permittivity and resistivity. These relations lose accuracy at high resistivity. However, by combining the two measurements, both the dielectric permittivity and resistivity can be determined without need for a transform. The dielectric resistivity extends the range of measurement, typically up to 3000 ohm-m.

See: attenuation resistivity,  dielectric permittivity,  phase shift,  phase-shift resistivity,  polarization horn,  propagation resistivity