Wave Depositional Formations

Wave Depositional Features

• Wave depositional features are formed on the coast when the oceanic border crashes and overtakes the land border.
• This process involves dumping sediments like sand, shells, and other materials carried by the waves onto the coast.

Swash and Backwash

• The swash of the wave deposits its load (seashells, rocks, and sediments) on the coast.
• The backwash pulls materials off the coast.

Cliff Retreat

• Original position of cliff: Initial state of the cliff.
• Wave-cut notch: A notch formed by wave action at the base of the cliff.
• Notch increases and cliff collapses: Erosion causes the notch to grow, leading to the collapse of the cliff.
• Cliff retreats: The cliff line moves inland over time.
• Wave-cut platform: A flat or gently sloping platform created by wave erosion at the base of the retreating cliff.

Beaches

• Beaches are formed as the swash of waves deposits sand and other materials, building up the soil.
• Beaches also form when rocks on the coast are broken down or eroded.

Spits

• A spit is created when the load of the wave is deposited and drifts in another direction, causing the soil to split away from the mainland.
• Prevailing wind: The dominant direction from which the wind blows.
• Longshore drift: The movement of sand and sediment along the coast.
  *Sand is deposited out at sea due to the longshore drift.

Tombolos

• A tombolo is a coastal landform that forms when a narrow strip of land, such as a sandbar or spit, connects an island to the mainland.
• This forms a bar connecting the gap between the mainland and the island.

Baymouth Bars (Baybars)

• Baybars are formed when a spit of deposition grows in front of a hollow opening, joining two headlands.
• Lagoon: An area of water dammed by the bar, which will gradually be infilled by deposition.
• A bar is formed as a spit grows across a bay, joining up two headlands.