Abstract
Summary: Deformation in unconsolidated sands requires the action of a deformation mechanism to reduce sediment strength and a driving force to induce deformation. Deformation mechanisms include liquefaction and fluidization and are reflected in the style of deformation and grain orientation fabrics. They are initiated by a trigger, including groundwater movements, wave action and seismic shaking. Driving forces include gravitational body force, unevenly distributed loads, unstable density gradients and shear forces, and are reflected in the geometry of deformation. These components are combined to produce a genetic classification of soft-sediment deformation processes and structures.