Slope Failure

Slope failure is the loss of stability on a submarine slope that lets sediment move downhill, the trigger event for slumps, debris flows, and turbidity currents. It occurs when the downslope driving shear stress exceeds the sediment’s shear strength, a balance captured by the effective stress that high pore pressure reduces. Common triggers are earthquake shaking, rapid deposition that outpaces drainage, gas-hydrate dissociation, and steepening at the shelf break or canyon walls. The failure leaves a headwall scarp and an evacuated scar. Slope failure on continental margins endangers offshore infrastructure and can launch tsunamis, and it is the source of most deep-sea mass-transport deposits.