The structure and evolution of deepwater basins in the distal margin of the northern South China Sea and their implications for the formation of the continental margin

Abstract

Abstract Although it is generally accepted that the South China Sea margin can be classified as a magma-poor rifted margin, little is known about the structural style of the distal margin and how the distal deep basins evolved. Observations and data from the Northern South China Sea margin suggest that the deepwater basins (distal margin domain) are commonly underlain by a highly extended continental crust, and detachment fault systems have been interpreted in places. We have interpreted a large seismic data set covering deepwater basins in the Northern South China Sea. The interpreted Moho on reflection seismic profiles indicates that the crustal thickness varies along sections perpendicular to the coast, which is the first-order criterion to divide the whole margin into a proximal domain, necking zone and distal domain. Furthermore, the underlying extremely stretched crust (