Formation Of Coastal Landforms

Question 1

Caves, arches, stacks, stumps

Answer 1

Hydraulic Action, Corrasion

Question 2

Spits, Bars, Tombolos

Answer 2

Longshore Drift

Question 3

Headlands and Bays

Answer 3

Differential Erosion

Question 4

Formation of a stack

Answer 4

Line of weakness in the rock is exploited by hydraulic action, a curve is created as hydraulic action is where the waves hitting a coastline force water and air into cracks, causing the cracks to split after widening. Overtime, the sea breaks thought the back wall of the cave and creates an arch. The sides of the arch are undercut through abrasion which is where waves throw material against a cliff face to wear it down. Eventually, the arches roof cannot support itself and it collapses to create a stack. The curve of the stack is again undercut until it too collapses to form a stump.

Question 5

Describe the formation of a spit

Answer 5

Spits are formed through deposition where large amounts of sediment are transported by longshore drift and where the coastline suddenly changes direction to leave a sheltered shallow area of water. Due to an increase in friction more deposition can occur in the water sheltered by the heather and the spit slowly builds up to sea level end extends in length. When the wind changes direction it causes the waves to alter that direction and this may result in some of the material at the end of the spit being forced inland to form a curved end. Salt marsh often develops behind the spit and spits cannot grow across an estuary as the river current carries material out to sea.

Question 6

Describe the formation of a bar

Answer 6

A bar is formed as a spit grows across a bay joining up two headlands