What is cuspate foreland?

Answer 1

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.

In a similar formation to that of salt marshes, the deposited matter is solidified by the encroachment of vegetation, which secures the material and develops the foreland into a feature of the coastline, and in time the more dominate wind, will shift the cuspate foreland down the coast at a rate depending on how relatively strong the secondary wind. This as with other landforms by the coast puts anything built on the Cuspate Foreland under threat from coastal erosion.