Recently, the Deep Sea Geophysics and Resources Research team at the Shenyang Institute of Deep Sea Science and Engineering of the Chinese Academy of Sciences, in conjunction with units such as Sun Yat-sen University, China University of Petroleum, Huadong, and University of Barcelona, Spain, conducted a study which revealed an active submarine fault zone in the northern South China Sea, the continental slope fault zone. The relevant results were published online in Marine and Petroleum Geology.
South China Sea Faults and Their Impact
Source: Interviewee
According to Dr. Zeng Fanchang, a Ph.D. student from the Deep Sea Science and Engineering Institute of the Chinese Academy of Sciences and Sun Yat-sen University, seabed fault activities can not only trigger earthquakes but also underwater landslides that lead to tsunamis, often causing greater damage than earthquakes on land. The spatial distribution, structural characteristics, and recent activity of active seafloor faults are critical parameters for marine geological hazard assessment.
Using high-precision multichannel seismic, gravity, magnetic, and seafloor topographic data, researchers conducted a systematic study of the active tectonics in the deep waters of the northern South China Sea, revealing the spatial distribution, structural characteristics, and recent activity of the Continental Slope Fault Zone. They found that the Continental Slope Fault Zone is an active fault zone approximately 1100 km long, trending NNE, and developed near the continental slope break. The plane/section of the Continental Slope Fault Zone (southeast Qiongdong section) exhibits a normal fault and strike-slip structural feature. Fault throw analysis and growth index indicate that the Continental Slope Fault Zone (southeast Qiongdong section) has experienced multiple activities since the late Quaternary. Combining the current seafloor topography, it is believed that the Continental Slope Fault Zone is likely to continue activities in the future, which may trigger a chain effect of underwater earthquake-landslide-tsunami hazards and pose significant geological hazard risks.
Dr. Wang Dawei, co-corresponding author of the paper and a researcher at the Deep Sea Science and Engineering Institute of the Chinese Academy of Sciences, pointed out that this study reveals the specific distribution, geometric structure, and recent activity of the Continental Slope Fault Zone in the northern South China Sea, providing basic data for geological hazard assessment work in Chinese waters.
The above research was supported by the National Key Research and Development Program, the National Natural Science Foundation of China, the Guangdong Province's Innovative and Entrepreneurial Teams for High-level Foreign Experts project, and other projects.
Relevant paper information: https://doi.org/10.1016/j.marpetgeo.2024.106777
