[Objective]To explore the characteristics of intraplate volcanic high-temperature geothermal resources in China, focus on the Yanggao-Tianzhen Basin in Datong, finely delineate the geological characteristics of volcanic high-temperature geothermal resources, and identify favorable exploration targets.[Methods]Based on the drilling and geophysical exploration data in the Yanggao-Tianzhen area, carry out the identification of heat transfer types, three-dimensional spatial inversion of resistivity and enhanced delineation of deep and large fractures.[Results]The Yanggao-Tianzhen Basin is composed of three sets of stratigraphic sequences from top to bottom, namely the Quaternary, Neogene + Paleogene, and Archean. The Quaternary strata serve as the regional cap rock, and heat is transferred in the form of heat conduction. The geothermal gradient in the eastern part of the basin is greater than that in the western part. The burial depth and type of heat sources control the formation and distribution of volcanic high-temperature geothermal resources. The heat sources are distributed in the northern and eastern parts of the basin, with a burial depth of 4,000 - 8,000 m, and there are obvious differences between the east and the west. The western part is mainly dominated by shallow-buried heat sources, while the eastern part has obvious magma channels connecting the shallow strata. The nearly east-west trending fractures are the most important heat-controlling and water-conducting fractures in the basin.[Conclusion]Three types of favorable exploration targets in the Yanggao-Tianzhen Basin have been proposed, including heat conduction type, magma eruption type and deep and large fracture-controlled type, with a total of 6 targets.
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