Structural features of the Jiangshao Fault Zone inferred from aeromagnetic data for South China and the East China Sea

Abstract

It is very important to ascertain the trend of the Jiangshao Fault Zone after it enters the East China Sea for the study of the South China Block. In this paper, we intended to solve the problem based on analysis of aeromagnetic data for South China, the East China Sea, and the adjacent areas. We described the distribution and structural features of the Jiangshao Fault Zone, and identified magnetic anomaly features, fault structures, and volcanic rock suites, along with the spatial distribution of igneous bodies with a high magnetic susceptibility. The spatial extent of the Jiangshao Fault Zone onland and offshore was determined through a comparison of the magnetic anomaly features with the geology and inferred structures. The Jiangshao Fault Zone extends from onland to offshore along a NE–SW trend. The formation of the Jiangshao Fault Zone was determined by comparing the stratigraphy and structures of the basement rocks, lithological units, and geological histories of the Yangtze and Cathaysia blocks. The spatial distribution of magmatic bodies with high magnetic susceptibility in the South China Block was revealed by the inversion results of aeromagnetic data. These findings contribute to understanding the tectonic evolution of the Yangtze and Cathaysia blocks, and provide insights into the geological structure of the East China Sea and formation of the East China Sea Shelf Basin.