A petrophysical experiment is described, which was conducted in the laboratory using data from geotechnical investigations in Neryungri, southern Yakutia. The purpose of the experiment was to find proofs of regional validity of the temperature dependence of one of the GPR dynamic parameters within the layer of annual temperature variations found earlier for urban areas of the Yakutian permafrost zone. The experiment has shown that the temperature dependence exists not only in the areas of continuous permafrost, but also in sporadic permafrost. An adequate forward and inverse mathematical model of the temperature dependence has been found and its accuracy examined using the factual data of the experiment.......