LONG-TERM PROFILE AND SEDIMENT MORPHODYNAMICS : 

 FIELD RESEARCH FACILITY CASE HISTORY 



PART I: INTRODUCTION 



1. This report provides an examination of the interaction between long- 

 term beach and nearshore profile changes and sediment grain- size distributions 

 across the profile. At the present, there is little guidance on the modeling 

 of sediment grain- size parameters in cross -shore changes in the beach profile. 

 This is the first report on the use of geological characteristics in interpre- 

 tation of coastal processes. It will focus on the morphodynamics (the change 

 in morphology due to the dynamics of coastal processes) of an oceanfront beach 

 over a 535-day period. The beach is constantly reshaping its profile and 

 sediment composition as it is being influenced by ever changing wave, wind, 

 tides, and longshore currents. A better understanding of this complex inter- 

 action is needed to improve beachfront erosion control and storm protection 

 project design. 



2. A unique data set of long beach profiles stretching from the dune 

 out 1,000 m into the nearshore is being collected on a continuous basis at the 

 Field Research Facility (FRF) of the US Army Engineer Waterways Experiment 

 Station (WES), Coastal Engineering Research Center (CERC) . This facility was 

 established to provide research and development capability for field studies 

 in coastal processes and shoreline response. As part of the operation, a 

 long-term data set of waves, currents, tides, atmospheric conditions, and 

 beach profile changes is continuously being collected. As a supplement to 

 this data collection, surface sediment grab samples were collected along one 

 profile line over a 17. 8 -month period from March 1984 to September 1985. Pro- 

 file surveys were taken on an approximately 2-week schedule, with the sediment 

 samples collected approximately once a month. Extra profiles and sediment 

 samples were collected after storms. 



3. This continuing collection of data is unique in providing a long- 

 term data set of accurate profile response to coastal processes. With the 

 addition of sediment samples for the study period, spatial coverage is pro- 

 vided along the profile over a long temporal period, with concomitant wave, 

 weather, and water-level information. This comprehensive data set provides a 



