W61- Sediment Transport, Estuaries

W61

Sediment Transport, Estuaries

ECTS

2.5

Specialities

HO

Keywords

Sediment transport, Mud, Sand, Turbidity, Sediment processes, Estuarine circulation

Description

Basics on sediment transport are given (sediment budget, sediment properties), then sediment processes are detailed. The flow in the boundary layer is described (in rivers, under waves, and under the combination of waves and currents). The threshold of motion is explained and transport into suspension is described. Specific processes for the transport of cohesive and non-cohesive particles are then exposed. This series of lectures ends by methodological information and examples.

The second part of the unit encompasses basic knowledge on estuarine circulation and sediment transport in estuaries. Examples are studied with the students, in an interactive process.

If possible, a field trip is organized in the Cam-Bach Dang estuary, or in Halong Bay, to introduce some instruments that are widely used in coastal oceanography and sediment transport studies (CTD, ADCP, turbidimeter, grain size meter, etc.)

Coordinators

Dr Sylvain Ouillon, IRD, Univ. Toulouse 3, UMR LEGOS, sylvain.ouillon@ird.fr

Lectures

Sediment transport: 1. Sediment budget, Continental and coastal sediment transport, Impacts; 2. Sediment properties (grain size distribution and sedimentological parameters, nature, density, settling velocity); 3. Boundary layer flow (directional, oscillating and combined flows); 4. Threshold of motion; 5. Transport into suspension (general model, Rouse profile, Richardson number); 6. Non cohesive sediment transport (bedload, suspension, bedforms); 7.Cohesive sediment transport (aggregation, settling velocity, erosion, deposition, erodibility, rheology of mud, mixed sediments); 8. Instrumentation; 9. Marine optics and applications to remote sensing (ocean color); 10. Studying sediment transport in Vietnam estuaries and coastal zones, some examples. 15h course.

An introduction to estuaries : 1- Morphological and geological features; 2- Salinity gradients; 3- Tide propagation and associated currents; 4-Estuaries classifications (Pritchard, Hansen & Rattray, Le Floch); 5- Estuarine residual circulation theories and application; 6- Sediment processes (turbidity maximum and fluid mud); 7- Long-term morphodynamic evolution; 8- Physical processes and management; 9-Case studies 5h.

Field trip (one day): training on instrumentation used in coastal oceanography and sediment transport studies (CTD, ADCP, turbidimeter, grain size meter, etc.)

Instructors

Dr Sylvain Ouillon, IRD, Univ. Paul-Sabatier, LEGOS

Vu Duy Vinh, VAST, Inst. Marine Environment & Resources (IMER), Haiphong

Control

examination + personal work (report and oral presentation)