Coastal Deposition

1
Coastal Deposition

• The main features formed by coastal deposition
  are
• sand spits,
• sand bars and lagoons,
• tombolos.

Each of these are formed as a result of longshore
drift
2
Longshore Drift

• Watch the animation!

3
Spit

• When the coastline changes direction suddenly,
  the beach deposits can continue in the former
  direction because of the effects of longshore
  drift, forming a spit.

4
Sand-bar and lagoon

• When beach deposits meet a bay, the bay
  becomes blocked off by a sand bar.
• Once the bay is cut off completely, we are
  left with a lagoon.

5
Tombolo

• A tombolo joins the land to an island