The Brazilian sea-level curves: a critical review with emphasis on the curves from the Paranaguáand Cananéia regions

Abstract

Relative sea-level curves for the mid-to late-Holocene have been proposed 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 Canankia regions in southeast Brazil. More specifically, we analyze the palaeo-sea-level indicators (vermetid tubes, shells, wood fragments and shell-midden deposits) related to (1) the sea-level maximum of the mid-Holocene and (2) the two secondary oscillations that would have occurred between 4100-3800 years B.P. and 3000-2700 years B.P. The sedimentary deposits of the coastal plain as well as vermetid datings suggest a mid-Holocene sea-level maximum between + 3.5 and +4 m. The great majority of the indicators used to infer the secondary oscillations in previous studies were derived from shell middens. Besides being unreliable palaeo-sea-level indicators. these data also showed inconsistencies that undermine the existence of such oscillations. The plot of all the data derived from vermetid samples found along the Brazilian coast also indicate a rather smoother sea-level fall in the last 5100 years. 0 1997 Elsevier Science B.V.

Holocene trophic state changes in relation to sea level variation in Lake Blanca, SE Uruguay

“…The lake forms part of a series of coastal aquatic systems that originated about 7000 years BP, after the first large Holocene marine transgression (Martin and Suguio 1992;Angulo and Lessa 1997;Isla 1998). This transgression was a consequence of glacioeustatic processes, and there were no significant changes in tectonic/seismic activity in the eastern coast of South America during the Holocene (Martin and Suguio 1992;Espinosa et al 2003).…”

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Shallow gas seismic structures: forms and distribution on Santa Catarina Island, Southern Brazil

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Protocolos para o monitoramento de habitats bentônicos costeiros - Rede de Monitoramento de Habitat Bentônicos Costeiros - ReBentos

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