First Direct Observations of Dilute Antarctic Turbidity Currents Associated With Dense Water Overflows

Abstract

Turbidity currents are increasingly recognised as a key mechanism for transporting sediment into the deep ocean, yet their structure, behavior, and long‐term impact in Antarctic submarine canyons remain poorly understood owing to a lack of direct observations. Using a year‐long mooring deployed in Wilson Canyon, western Ross Sea, we obtained the first in situ measurements of a dilute turbidity current associated with a slow moving dense water overflow in Antarctica, documenting a single event that lasted for 13 days and exhibited a distinct internal structure: a dense frontal head containing coarse sediment and cold, saline shelf‐derived water, followed by a prolonged body composed of finer sediment mixed with entrained ambient water. These observations provide further direct evidence that large volumes of dense water exported across Antarctic continental margins can trigger and sustain turbidity currents, supporting new insights into sediment resuspension and deposition in Antarctic submarine canyons and across continental margins, linking Antarctic Bottom Water formation to deep‐sea sediment transport processes.