GCSE Geography | Landforms of Erosion: Bays and Headlands (Coastal Landscapes 4)

Processes of erosion have led to the formation of distinctive coastal features - we call these erosional landforms.

Coastlines that have alternating bands of rock at right angles to the coastline are called discordant coastlines - along these bays and headlands often form.

How do bays and headlands form?

Bays and headlands form because of differential erosion rates - hard rocks, such as chalk and limestone, are more resistant than soft rocks, such as clay and sandstone, so they erode more slowly. This leaves a section of land jutting out into the sea called a headland. The areas where the soft rock has eroded away, next to the headland, are called bays.

Once a pattern of bays and headlands has become established the processes operating change. The bays are sheltered with calm shallow waters. This low energy means that deposition occurs, building up sandy beaches in the bay. Whereas the headlands are left exposed and start to experience more erosion because of wave refraction - meaning that as the waves approach the coastline they begin to take on the shape of the coastline. At the headland the waves become higher and steeper because of frictional drag, and the wave refracts (bends) around the headland to stop the wave crest from breaking - this means that more wave energy is concentrated on the headland, causing more erosion.

Longshore drift currents also converge at headlands, carrying material into the sheltered bays to build up beaches.

What are headlands like?

Headlands are cliffs that stick out into the sea and are surrounded by water on three sides. They are made of hard rock, e.g. chalk, limestone or granite, which are resistant to erosion.

Some characteristics:

• Huge piece of rock sticking out into the sea
• Very steep - almost vertical cliff face
• Often have caves eroded into the sides - these can develop into arches
• Overtime can develop into stacks and stumps

What are bays like?

Bays are crescent-shaped indents between two headlands, made from soft rock, e.g. clay or sandstone, which erode easily. The water in them is shallow and calm as they are sheltered, which enables sand to be deposited, forming beaches.

Some characteristics:

• Crescent-shaped beach
• Edge of the bay marked by two headlands
• Low energy waves - so good for swimming
• Lots of sand accumulated from both sides due to convergence of longshore drift