Synchronous variations in the Earth’s magnetic field and groundwater level

The magnetic field of the Earth is characterized by both irregular and quasi periodical variations in response to the disturbing influence of internal and external sources. The periodicity of temporal geomag netic variations registered at the surface is determined both by a global component related to changes in the solar activity and its consequences (ionospheric and magnetospheric perturbations) and by a local compo nent that reflects variations in the electric and geome chanical properties of surface crustal layers, such as electric conductivity, medium structure, and its deflection mode [13]. The groundwater regime is an important factor responsible, primarily, for electric conductivity and the deflection mode of the geophys ical medium.