THE BRAZILIAN SEA-LEVEL CURVES - A CRITICAL-REVIEW WITH EMPHASIS ON THE CURVES FROM THE PARANAGUA AND CANANEIA REGIONS

Relative sea-level curves for the mid-to late-Holocene have been propo sed for eight different sectors along the Brazilian coast. This paper aims to review the data used to construct the curves proposed for two sectors, the Paranagua and Cananeia regions in southeast Brazil. More specifically, we analyze the palaeo-sea-level indicators (vermetid tub es, shells, wood fragments and shell-midden deposits) related to (1) t he sea-level maximum of the mid-Holocene and (2) the two secondary osc illations that would have occurred between 4100-3800 years B.P. and 30 00-2700 years B.P. The sedimentary deposits of the coastal plain as we ll ss vermetid datings suggest a mid-Holocene sea-level maximum betwee n +3.5 and +4m. The great majority of the indicators used to infer the secondary oscillations in previous studies were derived from shell mi ddens. Besides being unreliable palaeo-sea-level indicators, these dat a also showed inconsistencies that undermine the existence of such osc illations. The plot of all the data derived from vermetid samples foun d along the Brazilian coast also indicate a rather smoother sea-level fall in the last 5100 years. (C) 1997 Elsevier Science B.V.