Geomorphology of subtidal and intertidal areas in the Southwest of the Netherlands

Abstract

For centuries tides have played a major role in the estuaries and sea-arms in the southwest of the Netherlands. Tidal currents are responsible for deposition of subtidal and intertidal sediments in which several characteristic geomorphological units can be distinguished. The tidal wave comes from the south of the North Sea. The tidal amplitude decreases from south to north and consequently the induced tidal currents reduce in velocity in the same direction. These changes are reflected in the deposits and their geomorphology. First an overview is given of the occurrence of different geomorphological units and their stability in estuaries from entrance landinward and the changes in the successive estuaries from south to north. Secondly an example is given of the differentiation and stability in a high silted-up intertidal area. The stability of the geomorphological pattern in these areas is not only governed by the tides. Aeration and physical ripening also become important.