The study looked at sand waves in the North Sea to understand how sediment changes along them. By collecting samples from different parts of the sand waves, the researchers found that the sediment composition, organic carbon, chlorophyll-a concentration, and permeability varied significantly between the gentle slope + crest and steep slope + trough of each sand wave. This suggests that there is a distinct sorting process happening along the Texel sand waves, with differences in grain size and permeability. These findings could help in designing offshore engineering projects by understanding how sediment sorting affects the seabed.