Erosional Landforms

Question 1

How are cliffs formed?

Answer 1

• through weathering + erosional processes

Question 2

Formation of steep cliffs

Answer 2

• most common where rock is strong + fairly resistant to erosion
• found in high energy environments
• sedimentary rocks that vertical strata are also more resistant to erosion, creating steep cliffs
• absence of a beach, long-fetch + high energy waves also promotes steel cliff development

Question 3

Formation of gentle cliffs

Answer 3

• most commonly found in areas with weaker rocks which are less resistant to erosion + prone to slumping
• found in low energy environments
• low energy waves also+ shirt fetch will lead to the formation of a secret mound at the base of the cliff, reducing cliff angle
• large beaches reduce wave energy + prevent development of steep cliffs by reducing erosion rates

Question 4

What influences the rate of retreat of a cliff?

Answer 4

• dependent on marine factors = fetch, beach, wave energy waves also
• terrestrial factors = sub aerial processes, geology, rock strength
• cliffs most likely to retreat if made from uncosnolidates rocks + sands

Question 5

Formation of a wave cut platform

Answer 5

• waves erode a cliff with the erosion mostly concentrated around the high tide line
• the main processes of hydraulic action + corrasion create a wave cut notch
• as the notch becomes deeper the clif becomes unstable + falls under its own weight throug mass movement
• this leaves behind a platform of the unaffected cliff base beneath the notch
• over time the same process relates leading to a wave cut platform to be formed

Question 6

Formation of caves, arches, stacks + stumps

Answer 6

This sequence occurs on headlands:
- waves enter faults + cracks in the headland + erode the cracks through processes of hydraulic action + abrasion
- the cave will widen due to both marine erosion + sub aerial processes, eroding the other side of the headland = creating an arch
- the arch continues to widen until its unable to support itself, falling under its own weight through mass movement
- this leaves behind a stack as one side of the arch becomes detached from the mainland
- as the base of the stack eventually to be eroded the stack eventually collapses into a stump