I have contour maps showing conductivity and in-phase data from an electromagnetic survey done on a ground, where, supposedly, an underground sewer system is running horizontally across the survey area. The In-phase data shows a clear indication of it, but the conductivity data is just blank.
Can anyone help me under stand why? Shouldn't the conductivity data show at least something? The survey was carried out both vertically and horizontally on the survey area using a CMD.
And what exactly does the in-phase data show in a electromagnetic survey? On the manual it just says that 'It is closely related to magnetic susceptibility of measured material.' Does this mean it's measuring the magnetic susceptibility?