| Sediment transport and bedform mobility in sandy shelf environment |
Funder identifier: MAS20029 (Other contract id)
Period: September 1995 till October 1998
Status: Completed
Thesaurus terms Bathymetry; Coastal waters; Hydrodynamics; Sediment transport; Seismic profiles
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| Institutes (3) |
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- Universiteit Gent; Faculteit Wetenschappen; Vakgroep Geologie; Renard Centre of Marine Geology (RCMG), more
- Vlaamse overheid; Beleidsdomein Mobiliteit en Openbare Werken; Vlaams Ministerie van Mobiliteit en Openbare Werken; Agentschap voor Maritieme Dienstverlening en Kust; Afdeling Kust, more
- Eurosense Belfotop NV, more
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| Abstract |
Morphological modelling of a linear sandbank is based on the complex interaction between water motion, sediment transport, and bed topography. STARFISH intends to analyze these interactions by monitoring in the field the hydrodynamic parameters, the non-cohesive particle transport mechanisms, and the bedform mobility with the help of a comprehensive and multi-disciplinary set of instruments. A number of instrumented tripods will be deployed on the Middelkerke Bank (southern North Sea) to measure the suspended-load transport rates, current velocities, and the migration rate of smaller bedforms in order to allow a more comprehensive understanding of the circulation patterns around the bank. The deployment of instrumented platforms will coincide with other activities such as sampling and side-scan sonar registrations which will map the present bedforms around the instrumented platforms. The volumetric evolution of the bank will be analyzed through time series of bathymetric recordings. The observed changes in shape and volume will be correlated with the meteo-marine and hydrodynamic characteristics which will be recorded during the entire project. Volume and shape of complete sections of the bank will be calculated with the help of a multi-bean echosounder. Time series of side-scan sonar operations will allow the detection of the changes in sediment transport paths and the displacement of bedforms. Boxcoring and vibrocoring operations will reveal the internal structures of the superficial sediments.
The morphological changes occurring on the beach in front of the Middelkerke Bank, such as erosion and accumulation, will be parameterized numerically and will be related to phenomena acting in the offshore. Emphasis will be put on sediment interactions between beach, nearshore and offshore. Work in very shallow waters will be carried out with the help of small survey vessels and a hovercraft. The internal structures of two other sandbanks (Celtic Sea Bank, a moribund sandbank situated at a depth of 100 m and the Bassure de Baas Bank, a bank with a rocky substratum) will be recorded using high resolution seismics and subbottom profiling. Coring will be carried out on the Middelkerke Bank and the Bassure de Baas Bank providing information on the nature of the bank sediments and allowing a lithostratigraphic interpretation of the seismic recordings. |
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