The seasonal evolution in the sediment textural characteristics along the Tinto and Odiel river estuaries
has been studied by means of 12 sediment traps. The fine-grained material is associated with flocculation
and decantation processes that take place in the zones of saline mixing and acid neutralization of both
estuaries. The bed load deposits are related with two different processes. In winter they are located in the
confluence of the fluvial and tidal currents, while in spring and summer, they are redistributed by the tidal
currents that deposit them in the central zones of the estuaries