Abstract: The traditional temperature and pressure field analysis approach, which is based on the interpolation of existing borehole data, cannot accurately represent the seepage-heat transfer coupling process of geothermal resources, resulting in insufficient understanding of the genetic mechanism of geothermal resources. First, a high-precision three-dimensional geological model of Zhangye Basin is built by combining multi-source data including borehole information, geophysical information and elevation data. Compared with the traditional interpolation model, multi-source data fusion modeling can improve the accuracy of inter-hole strata by 50-300 m. The numerical simulation of basin seepage-heat transfer field coupling process is carried out. The results show that the multi-field coupling analysis more reasonable represents the temperature and pressure characteristics of the reservoir than the key point spatial interpolation approach. The geothermal water in the study area flows from southeast to northwest and supplies the reservoir via faults. The geothermal field totally heats it during the seepage process. The temperature field is high in the basin center and low around it, with the central temperature reaching 78℃. The water head is greater towards the southeast of the basin's center and progressively drops to the northeast. Finally, a 3D geothermal conceptual model is developed to explain the genetic mechanism of geothermal resources in terms of structural, hydrogeological, and geothermal geological perspectives. This 3D conceptual mode coupling with heat-flow transfer modeling more specifically explain the spatial distribution and reveal more clearly the underlying mechanism of forming the geothermal resources compared with conventional 2D model.
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