Dam97

Formation

Cuspate forelands develop mainly as a result of long shore drift that occurs in two directions, merging two spits into a triangular protrusion into the sea by converging the material onto one location.

In normal circumstances, spits are formed when long shore drift moves beach material down the beach until the coastline makes an abrupt change in direction, leading to the beach material 'spilling over' the corner to create a protrusion (for example: this normally occurs across a river mouth). In the case of a cuspate foreland, the prevailing wind and a powerful secondary wind in the opposite direction move shingle down the coastline from both directions to a place where the coastline changes, causing a foreland to develop. The majority of cuspate forelands are formed over a coastline that juts out into the sea at enough of an angle to allow the drifting beach material to 'spill over' as a result of long shore drift in both directions.

The movement of sediment in longshore drift creates a cuspate foreland