Debris Flow

A debris flow is a gravity-driven mass of poorly sorted sediment and water that moves downslope as a cohesive, plastic body rather than a turbulent suspension. The sediment is supported by matrix strength and buoyancy, so it carries large clasts and freezes in place when the driving stress drops below the yield strength, leaving an ungraded, matrix-rich deposit called a debrite. On continental margins debris flows form by the disintegration of submarine slumps and can travel hundreds of kilometers across gentle slopes. They sit between coherent slides and dilute turbidity currents in the spectrum of subaqueous mass movements and often transform downslope into turbidity currents.