Is there a true delta at the Ribeira de Iguape river mouth, S o Paulo State?

The study area corresponds to the coastal plain neighboring the Ribeira de Iguape river mouth in the S o Paulo State littoral,where the Iguape, Cananeia and Ilha Comprida municipalities are situated. This coastal plain exhibits an area of morethan 1,500 km2. It has been interpreted as a consequence of shallow marine sedimentation of Pleistocene and Holocene,attributable to Cananeia and Santos transgressions, occurred during the last two interglacial stades named Sangamon andHolocene, intercalated by the last glacial stade named the Wisconsin according to the North-American nomenclature.However, without any scientific fully justifiable evidence, it has been hypothetically postulated that this coastal plain couldrepresent an oceanic delta associated with the Ribeira de Iguape river mouth, which is the most important drainage alongthe S o Paulo State coastline flowing to the Atlantic Ocean. This article has presented the data obtained by essentiallysedimentological studies, based on grain size and heavy mineral analyses, which brought important subsidies for a negativeresponse to the question: “is there a true delta at the Ribeira de Iguape river mouth (S o Paulo State, Brazil)?”.