Sandy beaches of the state of Paraíba: The importance of geological heritage

Abstract

The coastline of the State of Paraíba is approximately 145 km long. The sediment deficient character of this coast, with reduced sediment input, has resulted in long-term shoreline retreat. As a consequence, erosion of local sediment sources, such as the coarse grained Barreiras Formation, provided most of the sediment to the shoreline. These aspects, associated with a tropical climate, favoured the development of coral-algal reef structures and beachrocks which sheltered the shoreline from wave energy. The combination of medium to coarse sands and wave sheltering, has resulted in a dominance of reflective and low-energy intermediate beaches (i.e. ridge-runnel or low-tide beach terrace).