Registro sedimentario del antiguo canal de desembocadura del Río de La Plata en la plataforma continental del sur de Brasil

Abstract

This paper deals with the characterization of the geomorphology and paleo evolution of a La Plata River paleochannel, located on the south Brazilian continental shelf since the Upper Pleistocene. Through a bathymetric survey and coring of sediments from the paleochannel, a sedimentological and palynological analysis was carried out. This kind of analysis allowed us to characterize a transgressive depositional sequence on the La Plata River paleochannel. The palynological sequences indicated marine environments grading to mixohaline and continental freshwater. From a sedimentological point of view, the area is characterized as a fluvial-estuarine environment. These data offer new information to reconstruct the paleogeographic evolution of the La Plata River paleochannel on the Rio Grande do Sul continental shelf (Brazil).