Abstract:
Assessment of the current state of the near-surface part of the geological environment
and understanding of its layered structure play an important role in various scientific and applied
fields. The presented work is devoted to the application of phasometric modifications of geoelectric
control methods to solve the problem of the detailed complex study of the underground layers of the
environment in the process of drilling operations with the use of special equipment. These studies are
based on the analysis of variations in phase parameters and characteristics of an artificially excited
multiphase electric field to assess poorly distinguishable details and changes in the layered structure
of the medium. The proposed method has increased accuracy, sensitivity and noise proofness of
measurements, which allows for extracting detailed information about the heterogeneity, composition and stratification of underground geological formations not only in the zone where the drill
makes contact with the medium, but also in the entire control zone. This paper considers practical
mathematical models of phase images for basic scenarios of drill penetration between the layers of
the near-surface part of the geological medium with different characteristics, obtained by means of
approximation apparatus based on continuous piecewise linear functions, and also suggests the use
of modern machine learning methods for intelligent analysis of its structure. Studying the phase
shifts in electrical signals during drilling highlights their value for understanding the dynamics of
soil response to the process. The observed signal changes during the drilling cycle reveal in detail
the heterogeneity in soil structure and its response to changes caused by drilling. The stability of
phase shifts at the last stages of the process indicates a quasi-equilibrium state. The results make a
significant contribution to geotechnical science by offering an improved approach to monitoring a
layered structure without the need for deep drilling.
