Consulta: subjectFacets:"Bottom shear stress"
Registros recuperados: 4
Data/hora: 02/06/2024 13:23:58

Aide mémoire de dynamique sédimentaire. 7ème édition
Provedor de dados: 5
Autores: Le Hir, Pierre.
This aide-mémoire is not a lesson on sedimentary dynamics but more of a calculation form. Its use implies a good knowledge of the involved processes. This report presents the basic formulations used for the calculation of the hydrodynamic forcings as well as the main sediment behavioural laws, in order to help the reader conduct a basic sediment transportation calculation.
Tipo: Text
Palavras-chave: Bottom shear stress; Boundary layer; Mathematical modelling; Transport rate; Cohesive sediments; Non cohesive sediments; Sediment dynamics; Contrainte de cisaillement au fond; Couche limite; Modélisation mathématique; Fonctions de transport; Sédiments cohésifs; Sédiments non cohésifs; Dynamique sédimentaire.
Ano: 2008
URL: http://archimer.ifremer.fr/doc/2008/rapport-6273.pdf

Wave- and current-induced bottom shear stress distribution in the Gulf of Lions
Provedor de dados: 5
Autores: Dufois, Francois; Garreau, Pierre; Le Hir, Pierre; Forget, P.
Simulations of both currents and waves were performed throughout the year 2001 to assess the relative contribution of each to their overall erosive potential on the Gulf of Lions shelf. Statistical analysis of bottom shear stress (BSS) was compared to sediment grain-size distribution on the bottom. The hydrodynamic features of the bottom layer coincide with the distribution of surficial sediments, and three areas with different hydro-sedimentary characteristics were revealed. (i) The sandy inner shelf ( &lt; 30 m) area is a high-energy-wave dominated area but may be subjected to intense current-induced BSS during on-shore winds along the coast and during continental winds mainly in the up-welling cells. (ii) The middle shelf (30-100 m) is a low-energy...
Tipo: Text
Palavras-chave: Gulf of Lions; 3D modelling; Bottom shear stress; Sediment transport.
Ano: 2008
URL: http://archimer.ifremer.fr/doc/2008/publication-6305.pdf

Contourite distribution and bottom currents in the NW Mediterranean Sea: Coupling seafloor geomorphology and hydrodynamic modelling
Provedor de dados: 5
Autores: Miramontes Garcia, Elda; Garreau, Pierre; Caillaud, Matthieu; Jouet, Gwenael; Pellen, Romain; Hernández-molina, F. Javier; Clare, Michael A.; Cattaneo, Antonio.
Contourites are common morphological features along continental margins where currents encounter the seafloor. They can provide long-term archives of palaeoceanography, may be prone to sediment instability, and can have a great potential for hydrocarbon exploration. Despite their importance and increasingly recognised ubiquitous occurrence worldwide, the link between oceanographic processes and contourite features is poorly constrained. In particular, it is unclear under which specific conditions sediments are mobilised, modified and deposited by bottom currents. Here, we aim to determine key bottom current characteristics (velocity and bottom shear stress) affecting contourite deposition, by assuming that recent oceanographic regimes may be extended back...
Tipo: Text
Palavras-chave: Sediment drift; Erosion; Oceanic circulation; Bottom shear stress.
Ano: 2019
URL: https://archimer.ifremer.fr/doc/00483/59426/62241.pdf

The effect of wave-induced turbulence on intertidal mudflats: Impact of boat traffic and wind
Provedor de dados: 5
Autores: Verney, Romaric; Deloffre, J; Brun Cottan, J.-c.; Lafite, R.
Semi-diurnal and fortnightly surveys were carried out to quantify the effects of wind- and navigation-induced high-energy events on bed sediments above intertidal mudflats. The mudflats are located in the upper fluvial part (Oissel mudflat) and at the mouth (Vasiere Nord mudflat) of the macrotidal Seine estuary. Instantaneous flow velocities and mudflat bed elevation were measured at a high frequency and high resolution with an acoustic doppler velocimeter (ADV) and an ALTUS altimeter, respectively. Suspended particulate matter concentrations were estimated by calibrating the ADV acoustic backscattered intensity with bed sediments collected at the study sites. Turbulent bed shear stress values were estimated by the turbulent kinetic energy method, using...
Tipo: Text
Palavras-chave: Seine Estuary; Intertidal mudflat; Bed erosion; Bed roughness length; Bottom shear stress; Boat waves; Wind waves.
Ano: 2007
URL: http://archimer.ifremer.fr/doc/2007/publication-2552.pdf