Date of Award
Master of Science in Geology
J. C. Boothroyd
The spatial and temporal variation in sediment volume and morphology for the foredune and intertidal beach at Charlestown, Rhode Island were monitored for 1 year by weekly, prestorm and poststorm surveys at 15 profiling locations along an approximately 1.5 km of shoreline. Three distinct patterns of sediment redistribution were observed: 1) a continuous accretion of sediment at the western end of the study area; 2) a seasonal trend of fall and winter erosion and spring and summer accretion; and 3) short-term, cycles of erosion and accretion from storms and fair weather respectively. Net gains in the sediment volume over the one-year period were the result of storms in the immediate area producing a dominant littoral drift to the west. Sediment transported to the west was restricted by the east jetty of the Charlestown Inlet and accreted on the beach face. The seasonal shift of sediment between the beach and shoreface produced decreases in sediment volume at all sites in the study area during fall 1982 and winter 1982-83, while increases occurred during spring and summer 1983. Longshore transport of sediment dominated over onshore-offshore variations along the western half of the study area, and effectively damped any onshore-offshore volume change during all seasons. Three different beach states associated with the storm-fair weather cycle have been identified under varying wave conditions: 1) dissipative, with a storm beach profile; 2) intermediate, with a poststorm recover or accretionary profile; and 3) reflective, with a mature accretionary profile.
Blais, Alan G., "Spatial and Temporal Variations of a Microtidal Beach: Charlestown Beach, Rhode Island" (1986). Open Access Master's Theses. Paper 2035.