Decadal scale stability of sorted bedforms, German Bight, southeastern North Sea

摘要

Complex, large-scale sorted bedforms have been investigated in the southeastern North Sea. We present a unique time series of sidescan sonar and multibeam backscatter data spanning 26 years (1977-2003). In the storm-dominated study area, sorted bedforms surrounded by fine sand plains, are widespread. Although, wave and current shear stresses indicate a frequent remobilisation of fine sediment and an episodic remobilisation of coarse sediment, it appears that existing patterns have remained essentially stable over a period of 26 years. Moreover, we observe the birth of new sorted bedforms. The observed patterns are interpreted as the product of a feedback-related sorting process consistent with a recent explanation of sorted bedform formation.