An international team including NOC researchers has directly observed submarine landslides for the first time, capturing how sandy sediment collapses through a process called breaching and generates powerful flows that transport carbon and pollutants kilometers into the deep ocean.

Using sonar, seafloor mapping and moored instruments, the team detected around 30 underwater landslides in 18 days, capturing three in unprecedented detail.

They observed how sandy sediment progressively collapses through a process called ‘breaching’. As sediment grains move apart, suction temporarily strengthens the seabed. Then, as this suction fades, sediment fails over minutes to hours, generating powerful flows of sediment that travel kilometers downslope. These direct observations reveal processes previously understood only through theory and experiments, with implications for many other sandy deltas and submarine canyons worldwide.