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Definition:
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The dielectric constant, electrical conductivity and electrical resistivity are the major electrical properties governing the flow of electric current through Frozen Ground. The dielectric constant of a soil/rock is a measure of the ability of it to store electrical energy in the presence of an electrostatic field; it is the ratio of the soil's permittivity to the permittivity of a vacuum. The electrical conductance of a soil is the inverse of the resistance offered by a soil to electrical current flow. Current flow under an electrical gradient in a frozen soil occurs almost entirely through the unfrozen water films. Electrical conduction is related to the thickness of these water films and their degree of interconnection; it decreases with decreasing temperature and increases with increasing pressure. Electrical resistivity is the property of a material that determines the electrical current flowing through a cube centimetre of the material when an electrical potential is applied to opposite faces of the cube. All these electrical properties are influenced by soil/rock type, density, salinity, temperature and, in particular, the unfrozen water content.
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