Deep mantle evolution of the South China Sea and its interaction with surrounding subduction systems

Abstract As one of the largest marginal seas in the Western Pacific Ocean, the South China Sea (SCS) has garnered significant attention due to its origin and tectonic evolution. Nevertheless, our understanding of the deep mantle evolution in the SCS and its interaction with adjacent subduction systems remains limited. This paper examines the interaction between subduction zone systems within and around the SCS by combining geophysical observations with 3-D geodynamic simulations. The geophysical observations reveal multiple subduction zones surrounding the SCS, suggesting a close relationship between its tectonic evolution and these neighboring subduction systems. This study presents a comprehensive three-dimensional geodynamic model that illustrates mantle evolution in the SCS, showing how mantle upwelling in its northern regions is connected to nearby subduction systems. Overall, the findings from the geophysical observations and geodynamic simulations indicate that the surrounding subduction zones significantly influence the deep structure of the SCS.