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TitreNumerical model predictions of seabed shear stress, sediment mobility and sediment transport in the Bay of Fundy
AuteurLi, M Z; Hannah, C; Perrie, W; Tang, C; Prescott, R; Greenberg, D
SourceAtlantic Geoscience Society Colloquim Abstracts; Atlantic Geology vol. 46, 2010 p. 59-60
Année2010
Séries alt.Secteur des sciences de la Terre, Contribution externe 20090378
RéunionAtlantic Geoscience Society (AGS) 2010 Colloquium; Wolfville, NS; CA; février 5-6, 2010
Documentpublication en série
Lang.anglais
Mediapapier; en ligne; numérique
ProvinceRégion extracotière de l'est
Lat/Long OENS -67.5000 -64.5000 45.5000 44.2500
Sujetsdistribution des sédiments; transport des sediments; sédiments marins; stabilité du sédiment; stabilité des pentes; glissements de pentes; marées; dépôts de marée; milieux de marée; géologie marine; sédimentologie
ProgrammeÉnergie renouvelable offshore, Géoscience en mer
Résumé(disponible en anglais seulement)
Seabed substrate stability and sediment dynamics are fundamental geoscience knowledge required for developing the tidal energy, and the overall sustainable development in the Bay of Fundy. Waves, tidal currents, and wind-driven and circulation currents were predicted from oceanographic models to assess the wave and current processes for the broader Bay of Fundy. The wave and current outputs were coupled with observed grain size in a sediment transport model (SEDTRANS) to predict the seabed shear stresses, sediment mobility, and sediment transport pattern in the region. Mean tidal current is the highest in the upper bay (> 1.2 m/s), reduced to moderate in the central bay (0.5¿0.8 m/s) and decreased further in the outer bay (0.2¿0.5 m/s). Maximum tidal current occurs in the Minas Channel and is greater than 5 m/s. Mean wave height, in contrast, is the greatest in the outer bay (~ 1.3 m) and gradually decreases to the northeast in the central and upper bay (< 0.5 m). Ocean circulation currents are largely less than 0.3 m/s. Maximum mean shear velocity on the seafloor due to combined effects of waves and currents reaches about 5 cm/s and is predominantly due to tidal current. Comparison between the model-predicted shear velocity from various processes and the threshold for bedload transport suggests that sediment mobilization is predominantly by tidal current and occurs nearly over the entire Bay of Fundy with maximum values reaching 100% of the time in several areas. Sediment mobilization by waves is generally restricted to small coastal areas. Total sediment transport rate can reach 1¿10 kg/m/s under spring tide condition. Net sediment transport averaged over a tidal cycle typically reaches 0.1 kg/m/s, and is dominantly to the top of the bay with local reversals and developments of eddies.
GEOSCAN ID261607