Discussion on the Cenozoic tectonic evolution of the South China Sea from continental margin extension

The formation and evolution of the South China Sea has been a long-standing debate in the field of geology. Many genetic models have been proposed by predecessors. The most popular model is seafloor spreading model, but it is difficult to reasonably explain the phenomenon of mid-ocean ridge jumping and continental debris in the South China Sea. We based on the stretch of the continental margin of northeast Eurasia, from the new continent drift model driven by mantle upwelling and gravitational slip along the Moho surface, using new geological explanation for several seismic profiles across the South China Sea, to study the process of the formation and evolution of the South China Sea, the result shows that the formation of the South China Sea is a kind of "passive tectonic extrusion + active microcontinents drift" mode. Passive tectonic extrusion was caused by the Indo-Eurasia collision, and the microcontinents formed by the extension of the continental margin drifted actively after extrusion. The seafloor spreading phenomenon in the South China Sea is the result of the active drift of many microcontinents. This new model can reasonably explain the mid-ocean ridge jumping phenomenon during the formation of the South China Sea and the genetic mechanism of the continental debris in the South China Sea. We have further recovered the movement and evolution history of the surrounding continents during the evolution of the South China Sea. It is concluded that the large scale extensional tectonic movement in the eastern margin of Eurasia in the Late Mesozoic was the foundation for the formation of the South China Sea, the India-Eurasia collision in Cenozoic was the direct driving force for the formation of the South China Sea, and the microcontinents drift was the main participant in the formation of the South China Sea. The proposed new continent drift model provides a new dynamic model for plate motion.