Lateral variation of aeromagnetic anomaly in South China and its tectonic implications

Abstract

We present a series of images from the aeromagnetic data observed in South China areas, and reveal the detailed structures of the South China Block. By using lateral variation of the aeromagnetic anomalies, we characterize individual geological blocks and suggest the deep boundaries of the blocks. The Yangtze Block and Jiangnan orogenic belt are characterized by low aeromagnetic anomalies, whereas high values of the aeromagnetic anomaly are observed in the Cathaysia Block. The boundary between the Yangtze and Cathaysia blocks, which remains unclear to date, can be plotted along the large magnetic gradients. The high magnetic anomalies significantly relate to volcanic distributions in South China areas. These aeromagnetic observations seem to be useful to investigate the intracontinental tectonic evolution in this region.