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| MAHIQUES,MICHEL M. DE; FIGUEIRA,RUBENS C.L.; ALVES,DANIEL P.V.; ITALIANI,DIANA M.; MARTINS,CRISTINA C.; DIAS,JOÃO M.A.. |
| The role played by human activity in coastline changes indicates a general tendency of retreating coasts, especially deltaic environments, as a result of the recent trend of sea level rise as well as the blockage of the transfer of sediments towards the coast, especially due to the construction of dams. This is particularly important in deltaic environments which have been suffering a dramatic loss of area in the last decades. In contrast, in this paper, we report the origin and evolution of an anthropogenic delta, the Valo Grande delta, on the south-eastern Brazilian coast, whose origin is related to the opening of an artificial channel and the diversion of the main flow of the Ribeira de Iguape River. The methodology included the analysis of coastline... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Anthropic activity; Delta; Sedimentation; Lagoon. |
| Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652014000401597 |
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| PEREIRA,NATAN S.; MANSO,VALDIR A.V.; MACEDO,RENÊ J.A.; DIAS,JOÃO M.A.; SILVA,ADRIANA M.C.. |
| Located 266 km offshore Brazilian coast, Rocas Reef complex is the only atoll in the South Atlantic. Two scientific expeditions carried out detailed sedimentological studies of the complex. Sand texture was dominant in the sedimentary environment, although other textures such as gravel, sandy gravel and gravelly sand, were also observed. Mean size ranged from fine sand to coarse sand (-1.23 to 2.34ø), with an average value of 0.69ø (sand fraction), which from a geological perspective represents a high-energy environment. The values of mean size varied in the different geomorphologic compartments, a response to variable hydrodynamics on the reef. Sorting ranged from very well sorted to poorly sorted, with a mean value of 0.97ø (moderately sorted). The... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Biogenic particles; Carbonate sediments; Atoll reef; Sedimentological parameters. |
| Ano: 2013 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652013000100057 |
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