The formation of a spit begins due to a change in the direction of a coastline, or a change in the prevailing wind direction. Where there is a break in the coastline and a slight drop in energy, longshore drift which has been occurring further up the coastline, will deposit material at a faster rate than it can be removed. A ridge (new land) will form out at sea. If the wind direction changes, or the spit begins to form over an estuary, the sand will start to curve forming a hook and recurved laterals. Sand dunes and vegetation can form on the hook. Eventually water will become trapped behind the spit and it will become marshy and muddy, this is known as a salt marsh. If the spit traps water behind it, this is known as a lagoon. If the spit is at right angle to the land, it is known as a divergent spit.
