34 Die Küste, 74 ICCE (2008), 31-44 
S*«b*d sediments of Gorman Bight 1 : 250.0 
Classification after Figge (1981) 
BaMocfc 
Bedrock Mjd 5-10% 
M fc*«* Mjd 11-20% 
llllll Bedrock Müd 21-80% 
OrevedStenee 
OreveVStonee Müd 9-10% 
> GreveVSlonee Mod 21-80% 
MeOun tend Mud 5-10% 
MeOum eend. fctod 11-20% 
i MeOwn eend. Mud 21-80% 
j MeOum eend. Mud > 50% 
Few tend. Mjd 5-10% 
Few eend Mud 11-20% 
| Few eend Mud 2180% 
| Foie eend. Mud » 90% 
| Mud (more tften 60%) 
•e eend MudM0% 
MeOun lo ooeree eend Mud 11-20% 
f Meaum to coarse eend Mud 21-80% 
MHum to coarse send Mud >90% 
V 
N5&jf 
GMdMctMm WGSM 
«■pPTCHfWt MwnW0HM‘N) 
Fig. 3: Distribution of the surficial sediments (0-20 cm) of the German Bight (Figge, 1981). 
(Source: Shelf Geology Explorer, BSH) 
0-10 m, the thickness of the mobile sediment cover is up to 10 m; a relatively thin layer of 
mobile sandy material is located between 10-15 m of water depth, and a slight increase in 
thickness of 2-3 m with local maxima of about 5-6 m can be observed in water depths between 
15-20 m. A conceptual model of the net sediment transport regime is inferred from this pat 
tern. It comprises a relatively narrow zone of sediment in the littoral drift, resulting in a 
substantial sediment supply in the innermost German Bight and a shore-normal bed-load 
transport shifting sand to and fro in the coastal profile, with a net offshore component (Zeiler 
et al., 2000). 
During storm surges, sediment from tidal flats and sand bars can be transported offshore 
for more than 50 km down to water depths of 40 m below MSL. The average volume of 
sediment transported by a single storm has been estimated to be about 4.2 X 10 6 m 3 (Gadow 
and Reineck, 1969). Wunderlich (1983) demonstrated that large-scale sedimentary struc 
tures are shifted during storm wave action and remain stable during calm weather periods. 
They undergo only slight reworking processes. 
Similar processes are postulated by Diesing et al. (2006) for so-called “sorted bedforms” 
in offshore waters of the eastern part of the German Bight. They assume that extreme storm 
events play a major role in the generation of these structures, whereas average tidal currents 
form and maintain their final shape. It is noteworthy that the widespread sorted bedforms 
have shown stable patterns over a period of more than 26 years.