Abstract
Eqah island is a reef composed of argonite and calcite aged 1740 +/- 60 years. The Island is covered by medium to fine skeletal and non-skeletal carbonate sand of marine origin. The analysis of the surficial sediments shows a significant change in mean grain size along the beach (seaward side) which represents fining in the direction of the wave-driven movement and as a result. the increases in supply rate of fine sand particles from the north to the south direction. The beach against the land has larger grain sizes. This is due to the steep foreshore slope of the beach. The grain size distribution of the sediments are polymodal and well to moderately sorted.