Sand transport on estuarine submarine dune field

By means of surveys carried out with a Phase Measuring Bathymetric System and current profiles obtained through an ADCP of the internal area of the Bahía Blanca estuary, a field of large dunes was analysed. There are two different and well-defined zones characterized by particular dune morphology an...

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Detalhes bibliográficos
Autores: Gomez, Eduardo Alberto, Cuadrado, Diana Graciela, Pierini, Jorge Omar
Formato: artículo
Estado:Versión publicada
Fecha de publicación:2010
País:Argentina
Recursos:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/21347
Acesso em linha:http://hdl.handle.net/11336/21347
Access Level:acceso abierto
Palavra-chave:Sand Dunes
Adcp Profiles
Dune Migration
Swath Bathymetry System
https://purl.org/becyt/ford/1.5
https://purl.org/becyt/ford/1
Descrição
Resumo:By means of surveys carried out with a Phase Measuring Bathymetric System and current profiles obtained through an ADCP of the internal area of the Bahía Blanca estuary, a field of large dunes was analysed. There are two different and well-defined zones characterized by particular dune morphology and differing hydrodynamics. The reduction in the channel cross-section by a geological control leads to the increase in tidal current velocity, which together with the available sediment leads to the formation of Very Large Dunes (HN4 m and LN100 m) with the typical morphology of a limited amount of sediment overlying a rigid substrate. The migration rate of these dunes, between 65 and 130 m year−1 , decreases as the bedform height increases. Differing sediment transport rates across the channel result in a non-uniform migration rate, which is responsible for the formation of dunes with linear crests oblique to the tidal current direction. This fact indicates that determination of the sediment transport direction by using only large bedform orientation may be subject to a significant error.