Geology and hypsometry of river basins at central-northern Santa Catarina (Brazil): implications for the coastal zone

Abstract

The central-northern region of the Santa Catarina State (Brazil) is composed basically by the Itapocu, Itajaí-Açu and Tijucas river basins, draining directly to the South Atlantic. The present study uses the hypsometric analysis of those three basins to improve the understanding of the Holocene evolution and dynamics of the respective estuaries and coastal plains. Data on the lithological coverage, topography, hydrography, climate and dimensions were considered, analyzed and interpreted in the geomorphologic context. Information regarding hydrodynamics and sedimentology of the estuaries and stratigraphy of the coastal plains were also considered. The results have shown important differences in the geology, topography, thalweg profile and hypsometry between the studied drainage basins. In the corresponding estuaries and coastal plains substantial differences in the morphology, dynamic and stratigraphy were observed, which could be largely explained by the differences in the drainage basin characteristics.