Adaptive Window Approach for Curie Depth Calculation Based on Modified Centroid Method and the Application in the South China Block

Abstract

Curie depth plays an important role in the study of geological structures and resource exploration. Conventional methods usually employ a fixed window size for estimation, often resulting in significant inaccuracies. To overcome this deficiency, a new adaptive window Curie depth calculation approach is proposed, which can automatically select the optimal window size across a range of diverse geological conditions to achieve a more precise Curie depth. We validated the new approach using synthetic data, demonstrating that the average error of the bottom depth of the model was reduced compared to traditional methods. Subsequently, we applied the new method to real magnetic data from the South China Block, and a new Curie depth result was obtained and verified using measured ground heat flow data. The mean square error between the derived results and the measured ground heat flow was found to be lower than that of the Curie depth inversed by previous researchers. The adaptive window Curie depth calculation method presented herein exhibited high adaptability and accommodated various geological features. For the South China Block, the Curie depths exhibited a smooth and continuous pattern in stable regions such as cratons, while displaying a distinct uplift in the junction region between fault zones and blocks. This method can not only accurately capture the Curie depth variations across large areas, but also vividly highlight subtle changes in the Curie depth within smaller regions, demonstrating the superiority of this new approach.