The theory of resistivity logging (RL) originally stems from the Fock–Stefãnescu forward problem solution for the stationary electric field E in a piecewise homogeneous isotropic medium, with a single boundary corresponding to the surface of a cylinder unlimited by height. The cylinder simulates a borehole filled with drilling mud of resistivity ρ = ρb, which penetrates a formation with resistivity of rocks ρ = ρr. The primary field E is produced by the charge of a current electrode A placed on the cylinder axis. In this paper the forward problem for the field E is investigated for the electrode A at an arbitrary point off the axis of a borehole embedded in a transversely isotropic formation, with an anisotropy axis parallel to the borehole axis. The solution of forvard problem is used in algorithms and respective software for processing resistivity logs affected by electrode eccentricity and formation anisotropy. The changes caused to apparent resistivity by the two effects are estimated in percent for axial and lateral electrode dispositions.

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The Sergiev Posad polygon of the MGRI-RSGPU is located on the watershed of the Pazha and Torgosha rivers located on the southern slope of the Klinsky-Dmitrovsky ridge; geologically, the upper part of its section is composed of clay soils of Quaternary and Cretaceous age. The paper gives an analysis of the values of seismic, electrical and physical and mechanical properties of soils, as well as resistivity of water sources and reservoirs. Main methods of near-surface geophysics allow obtaining this information. The performed methods made it possible to specify the geological structure of the first 15 meters of the section, to refine the hydrogeological conditions of the test site, to determine the properties of the grounds as bases for buildings and structures. Also, the effect of the radioactive substance oonthe state of the underlying soils has been established by means of a specially prepared soil radiometer plate .