Sediment mobility in response to tidal and wind-driven flows along the Belgian shelf, southern North Sea
The effect of hydro-meteorological forcings (tidally- and wind-induced flows) on the transport of suspended particulate matter (SPM), on the formation of highconcentrated mud suspensions and on the occurrence of sand-mud suspensions has been studied using long-term multi-parametric observations. Data have been collected in a coastal turbidity maximum area (southern North Sea) where a mixture of sandy and muddy sediments prevails. Data have been classified according to variations in sub-tidal alongshore currents, with the direction of sub-tidal flow depending on wind direction. This influences... Mehr ...
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Dokumenttyp: | Artikel |
Erscheinungsdatum: | 2012 |
Sprache: | Englisch |
Permalink: | https://search.fid-benelux.de/Record/base-26920169 |
Datenquelle: | BASE; Originalkatalog |
Powered By: | BASE |
Link(s) : | https://www.vliz.be/imisdocs/publications/234717.pdf |
The effect of hydro-meteorological forcings (tidally- and wind-induced flows) on the transport of suspended particulate matter (SPM), on the formation of highconcentrated mud suspensions and on the occurrence of sand-mud suspensions has been studied using long-term multi-parametric observations. Data have been collected in a coastal turbidity maximum area (southern North Sea) where a mixture of sandy and muddy sediments prevails. Data have been classified according to variations in sub-tidal alongshore currents, with the direction of sub-tidal flow depending on wind direction. This influences the position of the turbidity maximum; as such also the origin of SPM. Winds blowing from the NE will increase SPM concentration, whilst SW winds will induce a decrease. The latter is related to advection of less turbid English Channel water, inducing a shift of the turbidity maximum towards the NE and the Westerscheldt estuary. Under these conditions, marine mud will be imported and buffered in the estuary. Under persistent NE winds, high-concentrated mud suspensions are formed and remain present during several tidal cycles. Data show that SPM consists of a mixture of flocs and locally eroded sand grains during high currents. This has implications towards used instrumentation: SPM concentration estimates from optical backscatter sensors will only be reliable when SPM consists of cohesive sediments only; with mixtures of cohesive and non-cohesive sediments, a combination of both optical and acoustic sensors are needed to get an accurate estimate of the total SPM concentration.