Tidal action as a cause of clay accumulation

Attributes the decrease in grain size and increase in clay content of bottom sediments toward inner shores of tidal flats such as the Wadden Zee (Netherlands) to the effect of settling lag and scour lag (here defined and described) accompanying decrease in velocity of tidal currents, noting that similar phenomena may be responsible for lateral changes in clay content of the sediments of estuaries, tidal lagoons, or similar environments in which current velocities decrease away from the open sea.