Magnetotelluric imaging of the northern margin of the Dabie orogenic belt: mplications for thermal structure
Wang-qi Ren, Guo-qiang Xue,*, Wei-ying Chen, Tao Chen
1. Logging Technology Research Institute, China National Logging Corporation, Xi’an 710077, China
2. School of Geosciences and Info-Physics, Central South University, Changsha 410083, China
3. Key Laboratory of Deep Petroleum Intelligent Exploration and Development, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China
4. College of Earth Science, University of Chinese Academy of Sciences, Beijing 100049, China
5. China National Logging Corporation, Xi’an 710077, China
Abstract：
To explore the high heat flow anomalies from the Dabie orogenic belt, We have set up 15 Magnetotelluric(MT) stations. The stations have an average spacing of ~2 km. Firstly, the phase tensor method is used to analyze MT data to estimate the dimensional characteristics of the underground resistivity structure. Then, based on the results of dimensional characteristics analysis, three-dimensional (3D) inversion was performed using ModEM, and a 3D resistivity structure from the surface to a depth of 30 km was obtained. It shows: that there are extensive low resistivity anomalies in the lower crust of the northern margin of the Dabie orogenic belt, which may be partial melting or water-bearing fl uid. The high heat fl ow anomaly in the northern margin of the Dabie orogenic belt may be due to the increase of the background heat fl ow value caused by the orogenic belt delamination during post-collision, the thinning of the lithosphere and the upwelling of the asthenosphere.
. Magnetotelluric imaging of the northern margin of the Dabie orogenic belt: mplications for thermal structure[J]. APPLIED GEOPHYSICS, 2025, 22(4): 899-909.
2025, Vol. 22 
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