Active Slope Failure, Sediment Collapse, and Silt Flows on the Modern Subqueous Huanghe (Yellow River) Delta

摘要

Post-depositional slope instability and bottom mass-movement processes strongly modify the progradational subaqueous slopes of the modern Huanghe (Yellow River) Delta. Wide, shallow gullies dissect the submarine slopes with gradients of 0.3 to 0.4 deg. Lower delta-front sediments experience in situ subsidence, forming numerous collapse depressions. These processes are pronounced over much of the delta, incising a redistributing the most recently deposited silt-rich sediment. Principal causative factors include low sediment strengths created by rapid deposition in the delta during annual peak discharges from the river and severe bottom perturbations by surface storm-generated waves.