Formation of Headlands and Bays

Headlands and bays form along coastlines with alternating bands of hard and soft rock:

1. Soft rock $e.g., clay$ is less resistant and erodes faster due to hydraulic action and solution.
2. Hard rock $e.g., chalk or sandstone$ is more resistant and forms headlands that stick out into the sea.
3. As erosion continues, bays form in areas of soft rock, becoming sheltered by the headlands.
4. Headlands become more vulnerable to erosion as wave energy concentrates on them.

Definition: A headland in Geography is a narrow piece of land that projects from a coastline into the sea, typically composed of harder, more resistant rock.

Example: The formation of headlands and bays can be observed in many coastal areas, such as the Jurassic Coast in England.

Highlight: The interplay between rock resistance and erosion processes is key to understanding the formation of headlands and bays geography GCSE content.

Caves, Arches, Stacks, and Stumps

These coastal features form through a progressive erosion process:

1. Caves: Hydraulic action, abrasion, and solution erode lines of weakness in a headland, forming caves.
2. Arches: Caves deepen and widen on both sides of the headland until the sea cuts through, forming an arch.
3. Stacks: The rock at the top of the arch becomes unsupported and eventually collapses, forming a stack.
4. Stumps: Continued erosion of the stack leads to its collapse, leaving a stump.

Vocabulary: A stack in coastal geography is a tall, isolated rock formation created by wave erosion.

Example: Old Harry Rocks on the Jurassic Coast is a famous example of stacks formed through this process.

Highlight: Understanding the formation of caves, arches, stacks and stumps is essential for National 5 Geography students studying coastal landforms.

Cliffs, Wave-cut Notches, and Wave-cut Platforms

These coastal features are formed by wave erosion:

• Wave-cut notches are created at the base of cliffs by wave erosion.
• As erosion continues, the cliff face retreats, leaving behind a wave-cut platform.
• Wave-cut platforms are sloping rocky platforms exposed at low tide.

Wave energy, which controls erosion, is influenced by:

• Prevailing wind $most common wind direction$
• Wind strength
• Fetch $distance of open water between shores$

Definition: A wave-cut platform is a gently sloping rocky surface formed by wave erosion at the base of a cliff.

Highlight: The study of cliff erosion and platform formation is crucial for understanding coastal processes in BBC Bitesize National 5 Geography courses.

Longshore Drift and Beach Formation

Longshore Drift $LSD$ is a key process in coastal geography:

• It's determined by the direction of the prevailing wind and influences how beaches move over time.
• The swash carries material up the shore at an angle, while the backwash drags it back perpendicular to the shore.
• This zigzag movement transports sediment along the coast.

Beaches:

• Made of loose sediment $sand and shingle$
• Form between low and storm tides
• Commonly form in bays where waves have less energy
• Can also form along straight coastlines due to longshore drift

Vocabulary: Longshore drift is the process by which sediment is transported along a coastline by wave action.

Example: Groynes are often built by coastal authorities to slow down the process of longshore drift and prevent beach erosion.

Highlight: Understanding longshore drift is essential for studying beach formation and coastal management in National 5 Geography.

Spits and Bars

Spits are formed by longshore drift:

1. Sediment is carried along the coast by longshore drift.
2. When there's a change in coastline shape, a long, thin ridge of material is deposited, forming a spit.
3. A hooked end can form if there's a change in wind direction.
4. The water behind a spit is sheltered, leading to the formation of salt marshes and mud flats.

Bars:

• Sometimes a spit can grow across a bay, joining two headlands.
• This is known as a bar.
• Bars can trap shallow lakes behind them, called lagoons.

Definition: A spit in coastal geography is a long, narrow accumulation of sand or shingle extending from the land into the sea.

Example: Spurn Point in East Yorkshire is a classic example of a spit formed by longshore drift.

Highlight: The formation of spits and bars is an important topic in BBC Bitesize Nat 5 Geography coasts curriculum.

Coastal Landforms on OS Maps

Ordnance Survey $OS$ maps use specific symbols to represent coastal features:

• Cliffs are shown as thick black lines with tick marks pointing downslope.
• Headlands appear as land projecting into the sea.
• Wave-cut platforms are indicated by a rocky foreshore symbol.
• Stacks are shown as small circular islands close to the shore.
• Beaches are represented by a stippled pattern, often labeled as 'Sand' or 'Shingle'.

Six-figure grid references are used to precisely locate features on the map:

• First three digits represent the easting $x-axis$
• Last three digits represent the northing $y-axis$

Example: A cliff might be located at grid reference 766356, where 76.6 is the easting and 35.6 is the northing.

Highlight: Being able to identify coastal landforms on OS maps is a crucial skill for National 5 Geography students, particularly when studying physical environments.

Coastal Erosion Processes

Coastal erosion involves the wearing away of rock and soil through various processes:

Hydraulic Action: The power of waves forces water and air into cracks in rocks, building up pressure until the rocks break apart.

Corrasion: Also known as abrasion, this process involves rocks carried by waves being thrown against cliffs, breaking them down.

Solution: Sea water dissolves rocks, particularly those containing calcium carbonate, causing them to break down.

Attrition: Stones and pebbles transported by waves break down by crashing into each other.

Wave Pounding: The weight and force of falling waves breaks down rocks.

Vocabulary: Corrasion is the process where rocks and pebbles carried by waves erode the coastline through abrasion.

Highlight: Understanding these erosion processes is crucial for studying coastal landforms in National 5 Geography physical environments.