On application of fractal magnetization in Curie depth estimation from magnetic anomalies

  • Chun-Feng LiEmail author
  • Duo Zhou
  • Jian Wang
Research Article - Applied Geophysics


As an independent geothermal proxy, the Curie-point depth has important geodynamic implications, but its estimation from magnetic anomalies requires an understanding of the spatial correlation of source magnetization, mathematically characterized by a fractal exponent. In this paper, we show that fractal exponent and Curie depth are so strongly inter-connected that attempts to simultaneous or iterative estimation of both of them often turn out to be futile. In cases of true large Curie depths, the iterative “de-fractal” method has a tendency of overcorrecting fractal exponents and thereby producing erroneously small Curie depths and smearing out true geological trends. While true fractal exponent can no way be constant over a large area, a regionally fixed fractal exponent is better than any mathematical treatments that are beyond the limit of data resolution and the underlying physics.


Curie depth Geothermal structure Heat flow Fractal magnetization Magnetic anomalies Inversion North America 



This study is funded by National Natural Science Foundation of China (Grant Nos. 41776057, 41761134051, 41704086 and 91858213). Data mapping is supported by GMT (Wessel and Smith 1995). We thank anonymous reviewers for their critical but positive suggestions.


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Copyright information

© Institute of Geophysics, Polish Academy of Sciences & Polish Academy of Sciences 2019

Authors and Affiliations

  1. 1.Department of Marine SciencesZhejiang UniversityZhoushanChina
  2. 2.Laboratory for Marine Mineral ResourcesQingdao National Laboratory for Marine Science and TechnologyQingdaoChina
  3. 3.Key Laboratory of Crustal Dynamics, Institute of Crustal DynamicsChina Earthquake AdministrationBeijingChina

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