GPR and Geoelectrical Investigations for the Determination of Geothermal Properties in Shallow Geothermal Systems

The spatial distribution of thermal properties is important for the designing and monitoring of geothermal installations, therefore a non-invasive, high-resolution geophysical investigation of the thermal properties is eligible. The knowledge of the temperature dependant interrelations between relative dielectric permittivity, electric conductivity and the thermal conductivity is the basis for a geophysical investigation for shallow geothermal uses. Geotechnical properties such as water content, compaction, pore volume and mineralogy are strongly influencing the geothermal properties of soil. At the same time the geophysical properties of soil are dependant on these geotechnical properties. In this work the basically interrelations between geotechnical, geophysical and geothermal properties are presented and a geophysical investigation method of shallow geothermal systems is proposed.