Temporal variations in point bar morhphology within two incised river meanders, goodwin creek, mississippi

摘要

Two meander bends along Goodwin Creek, Mississippi, were chosen to examine incised-meander migration processes, bank failure mechanics, and point bar respose. Detailed topographic surfveys of the point bars over a two-year period reveal discrete episodes of net change in bar morphology. Sediment erosion generaly occurred during Winter/Spring months, was associated with moderately high flow discharges, and bar surface texture tended to become coarser-grained. Sediment deposition generally occurred during Summer/Fall months, was ssociated with the highest flow discharges, and bar surface texture tended to become finergrained. Net changes at each bendway site occurred in synchronicity and of nearly equal magnitudy, and show net vertical accretion rates of 30 mm yr~(-1).