This work is devoted to considering the issue of using the compensatory method of geoelectric control using the phase characteristics of the field to detect and localize geodynamic processes using the example of the development of a karst-suffusion cavity. The high noise immunity of the phasemetric method for recording geoelectric signals was noted in comparison with the amplitude parameters of the anomalous component of the electromagnetic field, usually used to analyze observation results. A formalized approach to the use of field phase characteristics to interpret monitoring data and the related problem of localizing geodynamic processes has been developed. Within the framework of this approach, it is proposed to determine the section parameters by the minimum sum of the weighted mean square error of interpretation and the regularizing functional containing a priori information about the geoelectric section. To check the possibility of localizing a spherical karst-suffosion cavity, modeling of the amplitude and phase of the anomalous component of the field potential, as well as the root-mean-square error of heterogeneity localization, was carried out when the center of the sphere moves along the installation profile. Modeling showed good differentiation of the potential from the location of the inhomogeneity; the highest localization accuracy was achieved with the combined use of the amplitude and phase components of the field in the problem of localizing the inhomogeneity.