Geology of Wave Cut Platforms

Questions and Answers

How is a wave cut platform formed?

The sea attacks the base of the cliff between high and low water mark, forming a wave cut notch by abrasion and hydraulic action. As the notch increases in size, the cliff becomes unstable and collapses, leading to the retreat of the cliff face. The backwash carries away the eroded material, leaving a wave cut platform.

What is an example of a wave cut platform?

At Southern Down, South Wales, UK.

What is a discordant coastline?

Where the geology alternates between strata or bands of hard rock and soft rock.

What is a concordant coastline?

Has the same type of rock along its length. Signup and view all the answers

What is a headland?

A narrow piece of land that projects from a coastline into the sea. Signup and view all the answers

What is a bay?

A broad inlet of the sea where the land curves inwards. Signup and view all the answers

How are headlands and bays formed?

Bands of soft rock erode quickly forming bays, while hard rock remains, projecting into the sea as headlands. Signup and view all the answers

When can a headland and bay form?

When a stretch of coastline is formed from different types of rock, causing cliffs to erode at different rates. Signup and view all the answers

Where are caves, arches, stacks, and stumps commonly found?

On a headland. Signup and view all the answers

How are caves, arches, stacks, and stumps formed?

Cracks in the headland are widened by hydraulic action and abrasion, forming caves. Caves can grow larger and break through to form arches, which eventually collapse into stacks that are undercut to form stumps. Signup and view all the answers

Study Notes

Wave Cut Platforms

Formed when the sea attacks the cliff base between high and low tide marks.
A wave cut notch is created by processes such as abrasion and hydraulic action, resulting in a dent at high tide level.
As the notch enlarges, the cliff loses stability and collapses, causing retreat.
Eroded materials are removed by backwash, leaving behind a wave cut platform.
The cycle continues, perpetuating cliff retreat.

Example of Wave Cut Platform

Located at Southern Down, South Wales, UK.

Discordant Coastline

Characterized by alternating bands of hard and soft rock in its geology.

Concordant Coastline

Contains a uniform type of rock along its length.
Typically features fewer bays and headlands compared to discordant coastlines.

Headland

Defined as a narrow segment of land that extends into the sea from the coastline.

Bay

Described as a broad inlet where land curves inward along the coast.

Formation of Headlands and Bays

Soft rocks, like clay or sand, erode quickly, leading to the formation of bays.
Hard rocks, such as chalk, resist erosion; as softer rocks erode, hard rock protrudes, forming headlands.

Conditions for Headland and Bay Formation

Occur when different rock types along a coastline erode at different rates.

Features Found on Headlands

Caves, arches, stacks, and stumps are commonly found on headlands.

Formation of Caves, Arches, Stacks, and Stumps

Initial widening of cracks in headlands occurs due to hydraulic action and abrasion.
Continued wave action enlarges these cracks into caves.
Caves can become large enough to break through the headland, forming an arch.
Erosion at the arch base causes the roof to collapse, creating a stack.
The stack is gradually undercut until it collapses to form a stump.

Description

Explore the fascinating processes behind wave cut platforms and their formation along the coastline. Learn about the effects of erosion, the differences between discordant and concordant coastlines, and features like headlands and bays. This quiz delves into the dynamic relationship between the sea and coastal landforms.