FIELD OBSERVATIONS ON SMALL SCALE SEDIMENTATION PROCESSES

[摘要] A series of field experiments have been conducted to investigate small-scale sediment dynamics near the seabed in the nearshore region. The experiments took place at the U.S. Army Corps of Engineers Field Research Facility, in Duck, North Carolina, U.S.A., where the seabed typically consists of fine to medium sized sand. An array of instrumentation was deployed at various locations across the surf zone and nearshore region between depths ranging from 1 to 5 meters. Examples of suspended sediment measurements are presented along with examples of observed bedforms. We observed that the suspension of sand tends to occur at low frequencies that correspond to the time scale of wave groups. Small wave ripples are also found to evolve over similar time scales. We explore the linkages between the suspension of sediment and the evolution of small wave ripples, and show that the size of the ripples plays a significant role in determining the amount and distribution of suspended sediment.

[学科分类] 建筑学

[关键词] sedimentation;field observation;small scale