Die Kuste, 81 (2014), 369-392 
375 
Hardly any porosity data is available for die German North Sea, especially for sandy sed 
iments. Porosity of marine sands in the tidal flats of the inner German Bight ranges by 
about 40 % (FUCHTBAUER and Reineck 1963). Porosity measurements were carried out 
for fine-grained sediments in die Elbe-Weser estuary during die AufMod project. 
Fig. 3 illustrates data points on the thickness of the mobile sand cover, which is used 
as a proxy for the available sediment budget. These data result from previous R&D pro 
jects and geological mapping programs. 
Figure 3: Thickness of the uppermost sediments (mobile sand cover and Holocene sediments) in 
the German Bight. 
3.2 Bathymetric data 
To describe the changes of the bathymetry we considered the digital terrain model as a 
continuous function z(x,y,t) in space and time. This digital batiiymetric model in space 
and time is represented by discrete survey points and associated interpretation methods.