The following are features formed by wave deposition:
This is an accumulation of sand, shingles, and pebbles at the coast.
It is caused by the deposition process of the wave when the swash is stronger than the backwash.
Spits are long, narrow landforms that extend from the shoreline into the sea. They are formed when longshore drift, the movement of sediment along the coast, carries material and deposits it in a protruding manner. Spits are often curved or hooked at the end due to changes in wave direction.
This is formed when two spits converge and join at the tips and it is triangular in shape.
This is an accumulation of water formed by seawater accumulating behind cuspate foreland.
A tombolo is a sandy or gravelly bar that connects an island to the mainland or another island. It forms when waves deposit sediment between the island and the mainland, creating a land bridge. Tombolos can be formed when longshore drift moves sediment from one area to another, creating a connection.
This is the ridge of materials usually the sand, which lies parallel or almost parallel to the coast. Unlike the spit, the bar is not attached to the mainland.
This is the platform of mud formed by the deposition of silt and river alluvium along the gently sloping coast, especially in bays and estuaries
Types of load moved by waves are such as shingles, sand, mud, and other objects dumped into the sea.
How the sea acquires its load
- Materials brought by rivers and wind.
- Products of weathering.
- Debris from volcanic eruptions in the sea or on land bordering the sea.
Waves transport load by a process called longshore drift.
Longshore drift is the progressive dragging of materials along the beach as a result of waves breaking at an angle.
mechanism of wave transportation
- Waves break at an angle.
- Swash pushes materials up the beach at an angle.
- Backwash brings them back at right angle to the edge of water.
- Process is repeated causing materials to be progressively dragged along the beach.Mocks,
Factors Influencing Wave Transportation
Strength of waves
Strong waves carry large quantities of load over a long distance while weak waves carry small quantities of load over a short distance.
Tides cause waves to break farther inland causing materials that were not in contact with breaking waves to be moved about.
Ocean currents cause movement of materials from one part of the ocean to another e.g. coconut fruits from the southern part of Africa to the Gulf of Guinea by Benguela current.
Gradient of the shore
On gentle coasts transportation of materials is favored by longshore drift while on a steep coast they bounce off cliffs and remain floating.
Orientation of coastline.
Transportation by longshore drift is favored where the coast is aligned obliquely to the direction of breaking waves while on transversely aligned coast swash moves materials back and forth along the same line.
Nature of the load
Lighter materials such as sand are carried over long distances while the heavy load is transported over a short distance.