Interpretation
At 0.5 Hz over 1.5 ohm-m sediments the field diffuses about 872 m before dropping to 1/e, so a resistor at 1500 m is best imaged near a 3900 m source-receiver offset.
Skin depth
872 m
Diffusion wavelength
5,477 m
Optimum offset
3,900 m
Peak anomaly
256.2 %
Resistivity contrast
40x
Radial electric field vs offset
The resistor lifts the curve above the background half-space at intermediate offsets.
Normalised anomaly
Ratio of measured to background amplitude - the quantity interpreters actually pick.
Phase lag vs offset
Phase advances where energy is guided through the resistive layer.