Small-scale morphology (< 5m horizontal wavelenght) was measured by combining CRAB surveys with bed elevations acquired form a 1 MHZ sonic altimeter mounted on the CRAB during the DUCK 94 experiment in October 1994.Bedform plan views were recorded ismultaneously using a 500 KH z side-scan sonar mounted on the CRAB.Waves and currents wre measured at the same time.Three cases are examine din detail: mild waves and weak longshore currents resulting in wave ripples throughout the study area; narrow-band,normnally incident waves with a strong rip current resulting in a planar bed except in the throat of the rip where megaripples wer emeasured; and storm waves with strong longshore currents resulting in lunate and straight-crested mega-ripples in the trough of hte barried beach.
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