Depositional mode for the seamount-terrace-canyon sedimentary combination under the impacts of intermediate and deep circulation dynamics in the northern margin of the South China Sea

As a natural laboratory for studying energy and material exchange at water-rock interfaces, the northern slope area of the South China Sea possesses complex geomorphology, such as uplifted seamounts, flat terraces, and depressed canyons. It also develops various types of deep-water depositional systems, including gravity flow slides/slumps, turbidity currents, and contouritic deposits. Based on high-resolution bathymetry and seismic reflection data, CTD data, as well as published results from marine sedimentology and physical oceanic numerical simulations, this study focuses on analyzing the seamount-terrace-canyon sedimentary combination under intermediate and deep circulation bottom currents on the South China Sea northern margins. This study identifies the seamount-related moat-drift systems, the erosional/sheeted-nondepositional/seamount related contourite terraces, the plastered drifts, as well as the steep slopes with slides/slumps and canyons. This research reveals the coupling relationship between these deep-water sedimentary combinations and the hydrodynamic patterns among the intermediate and deep circulations. The findings obtained have significant implications for further understanding of the response of deep-water depositional processes to intermediate and deep circulation hydrodynamics and their impact on shaping continental margin morphology.