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TitreNumerical Modelling of Seabed Disturbance and Sediment Mobility, and Implications to Morphodynamics on the Storm-dominated Sable Island Bank, Scotian Shelf
AuteurLi, M Z; Zou, Q; Hannah, C; Perrie, W; Prescott, R; Toulany, B
Source 2008 Ocean Sciences Meeting, from the watershed to the global ocean, book of abstracts; 2008 p. 1
Liens2008 Ocean Sciences Meeting
Année2008
Séries alt.Secteur des sciences de la Terre, Contribution externe 20070551
Réunion2008 Ocean Sciences Meeting; Orlando, FL; US; mars 2-7, 2008
Documentlivre
Lang.anglais
Mediaen ligne; numérique
ProvinceRégion extracotière de l'est
SNRC10N/16; 10O/13; 11N/04
Lat/Long OENS -61.5000 -59.0000 44.5000 43.2500
Sujetsmilieux de marée; marées; courants de marée; distribution des sédiments; transport des sediments; milieu sédimentaire; sedimentation; dynamique sédimentaire; propagation des ondes; courants; géologie marine; sédimentologie
ProgrammeAléas géologiques et contraintes à la mise en valeur des ressources extracôtières, Géosciences à l'appui de la gestion des océans
Résumé(disponible en anglais seulement)
Waves, tidal currents, wind-driven and circulation currents, and sediment mobility were modelled for one full year over the storm-dominated Sable Island Bank (SIB), Scotian Shelf. The mean shear velocity of tidal current and that of the wind-driven and circulation current are less than 2 cm/s, but the peak mean wave and combined wave-current shear velocities reach 4 and 4.5 cm/s respectively. Comparison between the model-predicted shear velocity and bedload threshold suggests that the circulation and wind-driven currents cause minimum sediment mobility on SIB. Tidal current and waves can each cause sediment mobility at least once a year over 36% and 71% of the bank area respectively, while the combined wave-current shear can cause sediment mobility over 93% of the bank area. Calculated time percentages of sediment mobility caused by various processes indicate that wave or wave-dominant disturbance is most important and occurs over >50% of the bank area, while mixed disturbance is also significant and occurs over ~ 30% of the bank area. Tide or tide-dominant disturbance occurs over only 10% of the bank area. Several parameters are proposed as universal indices for quantifying seabed disturbance and sediment mobility for coastal and shelf environments.
GEOSCAN ID224812