Landforms

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Erosional landforms

Bays

Formed when destructive waves erode areas of soft rock rapidly, through processes such as hydraulic action, abrasion, and solution.

They have a wide, open, semi-circular shape that extends into the sea, but is lower than the headland.

Headlands and cliffs

Areas of hard, resistant rock that isn't eroded as quickly, and left protruding out into the sea.

The sides are longer than the breadth, and form cliffs.

Wave cut platforms

Formed when erosion occurs at the high/low water mark continuously through hydraulic action, abrasion, and solution.

The rock is undercut at its weak point.

Caves, arches, and stacks

A fault occurs in headlands in the resistant rock.

Hydraulic action and abrasion erode the fault through wave refraction to form a cave.

The cave is widened and deepened.

The sea erodes through the cave to form an arch.

The sea erodes the foot of the arch and widens it.

The roof of the arch becomes too heavy and collapses.

Part of the former cliff is now isolated as a stack.

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Beaches

Formed in sheltered environments (e.g. bays).

Material eroded from cliffs is transported along the coast by longshore drift.

The amount of material varies with the type of wave.

When the swash is stronger than the backwash, deposition occurs on the shore, heavier materials first.

Spits

Eroded material is picked up by the coast.

It is transported by longshore drift along the coast in the direction of the prevailing wind.

Deposition begins at a bend in the coastline.

Freshwater and seawater are trapper behind the ridge, and a salt marsh may develop.

The deposited materials accumulate away from the coast.

A long ridge of sand/shingle is built up.

The spit extends into deeper water where winds and sea currents help to curve the end of it.

Sand dunes

A small embryo dune forms in the shelter behind the high water mark.

Sand is blown inland by strong onshore breezes.

Species like marram grass establish themselves in the dune and reduce wind speeds.

This traps fresh sand and makes the dune bigger.

Over time the marram grass adds organic matter to the dune and allows other plants to grow.

Driftwood and vegetation prevents more sand from being blown too far inland.