Heat flow distribution in southwest China calculated from the Curie depth

Summary Southwest China has well-developed geothermal resources due to the complete and intense geotectonic activities. Heat flow is an important geophysical property to represent thermal state of the earth and it is closely related to the Curie depth. Most previous studies are mainly based on estimation of heat flow from the Curie depth. To improve the quality and accuracy of heat flow, we propose an iteration approach of calculating the heterogeneous thermal conductivity laterally. Firstly, we calculate the distribution of surface heat production using the data of radioactive elements. Secondly, the thermal conductivity is obtained under the constraint of the Curie depth and surface heat production. Finally, the heat flow and its value underground of the study area can be obtained. The results show that the surface heat flow of southwest China is in line with the background trend of high in the southwest and low in the northeast. The surface heat flow are basically corresponding to the measured heat flow and regional geothermal anomaly.