View article

Turbidity currents generated downstream of rivers are the primary agent to transport land particles (eg nutrients, organic carbon, microplastics) to the deep sea. Turbidity currents can erode the seafloor by entraining seabed sediment, which can cause a hazard to seafloor infrastructures. It is thus important to understand how erosive turbidity currents are triggered off river deltas. Sediment settling from dilute (< 40g/L) river plumes have been shown to be the most frequent trigger on some deltas and to be capable of generating long run-out erosive turbidity currents. Yet the processes by which dilute river plume lead to turbidity currents are still unclear. Turbidity currents have been produced by'dilute river plumes' in laboratory experiments and numerical models when sediment density is able to overcome the density difference with saline water, settling out slowly from the surface plume. However, in natural river plumes …