Numerical membranous simulation of the electromagnetic field on the Voronezh crystalline massif and adjacent structures

Abstract

Introduction: Variations of the natural electromagnetic field allow studying the deep structure of the Voronezh crystalline massif and adjacent structures. Highly conductive rocks of the sedimentary cover have an effect on the nature of the observed geomagnetic field. Methodology: We conducted numerical membranous simulation to take into account the distortions of the observed magnetotelluric field within the Voronezh crystalline massif, Ryazan-Saratov trough, and Dnieper-Donets Rift by the regional galvanic and inductive effects. The sedimentary cover of these structures was approximated by the Price-Sheinman membrane with the set total longitudinal conductivity S(х,у). Results and discussion: Under the influence of a heterogeneous conductive sedimentary cover, the horizontal components of the electric field and the vertical component of the magnetic field were seriously distorted, while the horizontal components of the variable magnetic field were significantly less subjected to the impact of the conductive sedimentary cover. Conclusions: Taking into account the distortions of the variable electromagnetic field by the conductive sedimentary cover allowed assessing the anomalies of electric conductivity identified using geomagneticvariation and magnetotelluric data within the VCM and adjacent structures at various levels of the Earth's crust.