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Datong Basin is a Cenozoic fault basin located in the central part of the North China Block with strong tectonic activity. The unique geological environment of Datong Basin is believed to have good conditions for the formation of geothermal resources. Based on the research of the classification, genesis and geothermal geological characteristics of geothermal resources, the geological conditions, seismic activity, volcanic activity, geophysical exploration results, terrestrial heat flow and hot springs in Datong Basin are analyzed. The possibility of the occurrence of geothermal resources in Datong Basin is determined, and the genesis and occurrence mechanisms of geothermal resources in Datong Basin are judged. The results show that Datong Basin satisfies the geological geothermal conditions of the formation of geothermal resources and is of great research value. The formation of geothermal resources in the Datong Basin is affected by the uplift of the Qinghai–Tibet Plateau and the destruction of the North China Craton. The geothermal resources in Datong Basin are formed by the combination of modern volcanic activity and strong inner-plate tectonic activities. The geothermal system is a combination of convective hydrothermal systems and partial melt systems. At the same time, it is concluded that the key research areas for the occurrence of geothermal resources are mainly in the northeastern part of the basin. It is recommended to carry out detailed and comprehensive exploration of the northeastern part of Datong Basin.

Accurate estimation of the Earth's interior temperature is extremely important for studying both fundamental scientific and applied geothermal problems. Existing temperature estimation methods cannot provide reliable accuracy in the cross-borehole space and beyond the borehole’s depth; however, resistivity could overcome this difficulty as a temperature-dependent proxy parameter. At present, this approach is based on the use of purely empirical formulas, whose validity is unjustifiably postulated to be invariant with respect to geologic settings. This paper presents an electromagnetic geothermometer based on the coefficient correction method of the optimal temperature (CCMOT). This geothermometer can accurately determine the relationship between the normalized resistivity and temperature in an underground space based on resistivity-temperature logging data and electromagnetic data, and therefore, a visualized temperature distribution can be calculated. The CCMOT was applied to the subsurface temperature prediction in the Xiong’an New Area, with an accuracy of 86.69–97.25%. Sensitivity analysis of the key variables of the CCMOT revealed that the CCOMT has relatively little dependence on the number of constraining boreholes and the optimization of the subdivision spacing of the logging data can significantly improve temperature prediction accuracy. The CCMOT can be used to determine the distribution of the heat structure of the reservoir and to interpret the geothermal field. In addition, the CCMOT is of great significance to the evaluation, scientific development, and sustainable utilization of geothermal resources.