Geodynamic processes control sediment routing: Insight from the Earth surface evolution of the northern South China Sea margin and SE Tibetan Plateau.

Schematic representation of Isostatic balance between source and sink distribution of sediments and tectonics. [Display omitted] • The NSCSM evolved and linked with successive uplifts in SE Tibet Plateau. • Deep and surface parameters isostatically influence sediments and control their geometry. • Strengthening of lithosphere at the continental margin isostatically balanced with inland exhumation. Tectonic processes of the SE Tibet Plateau (SETP) and the northern South China Sea margin (NSCSM) strongly affected the surface drainage system for sediment transportation to deposition. It remains challenging to investigate the dominant mechanisms such as tectonics, deep dynamics, and surface processes. This paper aims to examine the influence of the SETP paleogeography on the NSCSM. Twenty-eight seismic profiles were quantified by flexurally interpolated backstripping and significantly correlated with the published paleogeography. A numerical simulation tool (Badlands) is assigned to study the integrated response of surface processes and deep dynamics. This paper inferred that drastic sedimentation changes in our models were linearly correlated mainly with erosion during the SETP uplifts, dynamic topography, and flexural isostasy. Deep dynamics and tectonic processes control basin architectures for sediment depositions, whereas the surface processes contribute isostatically in response to uplifts in the source region. We inferred that Eocene was the stage of extension, thinning of lithosphere (Te = 10 km) that is linked with the low topography (<2000 m) and erodibility (Є) of 5e-7 in the SETP. However, the increase in cumulative thickness is associated with strengthening the lithosphere (Te = 15 km) and tributary rotation with its rise in SETP topography (≥4000 m) during the Oligocene to Early Miocene. The Middle Miocene doesn't have the source-sink linkage for its high SETP topography with low deposition. But a strong connection with paleogeographic evolution in the later stage due to the rise in SETP topography and Taiwan orogeny. [ABSTRACT FROM AUTHOR]