  This paper describes the impedance spectroscopy adapted for analysis of small
electrochemical changes in fluids. To increase accuracy of measurements the
differential approach with temperature stabilization of fluid samples and
electronics is used. The impedance analysis is performed by the single point
DFT, signal correlation, calculation of RMS amplitudes and interference phase
shift. For test purposes the samples of liquids and colloids are treated by
fully shielded electromagnetic generators and passive cone-shaped structures.
Fluidic samples collected from different geological locations are also
analysed. In all tested cases we obtained different results for impacted and
non-impacted samples, moreover, a degradation of electrochemical stability
after treatment is observed. This method is used in laboratory analysis of weak
emissions and ensures a high repeatability of results.
