Levee toe scour: a mechanism of sediment reworking in the Paraná River Floodplain

RAMONELL, C.; DRAGO, E. C.; PAIRA, A.R.; AMSLER, M.

Cayastá y Santa Fe

Congreso; Workshop on Morphodynamic Processes in Large Lowland Rivers; 2007

Centro Internacional de Estudios de Grandes Ríos (CIEGRi) y The National Center for Earth-Surface Dynamics

Starting from the early fifties to nowadays, key paradigms concerning with the floodplain formative processes evolved in a non-linear way: the original model of vertical accretion was improved by the addition of the lateral accretion model (Leopold et al., 1964); later on, a new notion was introduced by Nanson (1986) with the concept of catastrophic stripping. Recently, the relative importance of the avulsion phenomena in the floodplain development was enhanced by Bridge (2003). It is noteworthy that more research on this topic is needed, as claimed by Rhoads (1994) and Parker (2000). In this context, the floodplain of the Middle Paraná River (maximum width: ca. 40 km; more than 600 km long) is a large wetland with a morphodynamics do not completely studied. A new mechanism of floodplain building for this large fluvial system is presented here.