TEXTURAL VARIATIONS OVER A FORESHORE-BACKSHORE ENVIRONMENT, HAWAII

Detailed textural analyses in a carbonate foreshore-backshore coastal environment in Hawaii indicated distinct differences in mean, sorting, skewness, and percent of fines between zones and within zones. A well-developed berm crest partitioned the 1,000 m2 grid into foreshore (n = 79) and backshore (n = 46) zones. As a group, foreshore sediments were finer, better sorted, and more negatively skewed than backshore sediments. This pattern was thought to reflect the decoupling of the foreshore source population by swash-backwash and eolian processes. Spatial variations in texture within the foreshore were also observed, and this led to the subdivision of the foreshore into three zones based on observed textural variations–lower foreshore, mid-foreshore, and upper foreshore. The lower foreshore was found to be statistically coarser, more poorly sorted, and more positively skewed than the other foreshore zones. The mid-foreshore zone was the finest, and the upper foreshore was intermediate in grain size. This ...