De contrasterende Holocene sediment successie langsheen het westelijk en oostelijk deel van de Belgische kust: oorzaak en gevolgen
Denys, S. (2007). De contrasterende Holocene sediment successie langsheen het westelijk en oostelijk deel van de Belgische kust: oorzaak en gevolgen. MSc Thesis. Vrije Universiteit Brussel, Faculteit Wetenschappen, Departement Geografie: Brussel. 94 pp.
|
| Beschikbaar in | Auteur |
|
Documenttype: Doctoraat/Thesis/Eindwerk
|
| Trefwoorden |
Erosion
Geological time > Phanerozoic > Geological time > Cenozoic > Quaternary > Holocene
Tidal deposits
Topographic features > Landforms > Coastal landforms > Tidal flats
ANE, België, Belgische kust [Marine Regions]
Marien/Kust |
| Abstract |
A series of drillings and cone penetrations tests carried out for the sea wall fortification along the shoreline was subject of a sedimentological and stratigraphical examination, revealing a difference in sediment succession between the western and the eastern part. In the western part, the Holocene sequence along the shoreline is entirely made up of coastal barrier deposits. In the eastern direction, starting from Middelkerke, such deposits are lacking, and the Holocene sequence consists of mudflat clay and peat layers incised by late Holocene tidal channels filled with sand and/or mud. This indicates considerable coastal erosion during the late Holocene in the eastern part. The difference in sediment succession may be caused by the very different morphology of the pre-Holocene subsoil in the west and the east. A fluvial valley characterizes the west. In the east, on the other hand, the Pleistocene subsoil consists of coversands, which may have formed a headland probably extending far to the north. In the palaeovalley, a tidal flat was formed from the start of the Holocene transgression, while the eastern headland did not come under the influence of the Holocene transgression until much later. Less sediment supply by interception of the longshore drift and a lowered shoreface profile caused strong shoreface erosion from the time when, 2400 to 2000 years ago, the tidal environment re-occupied the coastal plain. This shoreface erosion most probably affected the headland in a timespan of 1000 to 2000 years. This situation resulted in the eastern part of the coast still being subject to coastal erosion and consequently much more vulnerable than the western part. |
|
