Coasts

Question 1

Describe wave formation.

Answer 1

Water is pushed downwards then forced upwards, resulting in. oscillation of water particles to create waves.

This is because the surface of the sea exerts frictional drag.

Question 2

State the factors affecting the development of waves.

Answer 2

Fetch.
Depth of the ocean
Wind speed.

Question 3

Define Fetch as a factor affecting the development of waves.

Answer 3

Fetch is the open distance of sea over which a wind blows.

Question 4

How does depth of the ocean affect development of waves?

Answer 4

The deeper the ocean, the stronger the waves – oscillations continue to be complete.

Question 5

Swash usually carries out deposition. Define Swash.

Answer 5

This is when a wave breaks and water rushes up the beach.

Question 6

Backwash usually carries out erosion. What is Backwash?

Answer 6

When water runs back into the ocean due to gravity.

Question 7

What are the features of constructive waves?

Answer 7

1. Low crests and wave heights.
2. Long wave lengths.
3. Swash is stronger than backwash – thus they usually carry out depositon.
4. Frequency of 6 to 8 waves per minute.

Question 8

What are the features of destructive waves?

Answer 8

1. High wave crests and wave heights.
2. Short wave lengths.
3. Backwash is stronger than swash – so they usually carry out erosion.
4. Frequency of 10 to 15 waves per minute.

Question 9

Define Abrasion {or Corrasion} as a process of marine erosion.

Answer 9

Loose rocks{sediment}, are thrown against a cliff by waves, causing it to be chipped and worn away.

This results in chipped bits of rock.

Question 10

Define Attrition as a process of marine erosion.

Answer 10

Loose sediment, knocked of by Hydraulic Action and Abrasion crashes together, and wears away into smaller, rounder sediment.

Question 11

Define Hydraulic Action as a process of marine erosion.

Answer 11

Water is forced into cracks in a cliff, compressing air, and as the wave recedes, the air blasts out, forcing the rock apart.

Question 12

Define Corrosion as a process of marine erosion.

Answer 12

Sea water dissolves rock material.

{Happens usually along limestone and chalk coasts.}

Question 13

What is Solution as a process of marine transportation?

Answer 13

Dissolved material is carried along in solution.

Question 14

What is Suspension as a process of marine transportation?

Answer 14

Fine sediment is carried as suspension in the water, giving it a muddy, murky appearance.

Question 15

Describe Traction as a process of marine transportation.

Answer 15

Larger pebbles and cobbles{sediment} are rolled along the seabed.

Question 16

Explain Saltation as a process of marine transportation.

Answer 16

Small pebbles moving as they collide with each other, causing them to bounce.

Question 17

What is the major movement of material along a coast called?

Answer 17

Longshore drift.

This process is a result of wave transport.

Question 18

State four groups of features produced by wave erosion.

Answer 18

1. Bays and Headlands.
2. Cliffs and Wavecut platforms.
3. Blowholes and Geos
4. Caves, arches, stacks and stumps.

Question 19

State four features that are a result of marine deposition.

Answer 19

1. Spits
2. Bars
3. Tombolos
4. Coastal sand dunes

Question 20

Describe the formation of Bays and Headlands as features of wave erosion.

Answer 20

These are a result of waves eroding the soft rock faster than the hard rock on a coast made up of alternating bands of hard rock and soft rock.

– This leaves protrusions called headlands and indentations called bays –

Question 21

Describe the formation of cliffs and wave–cut platforms as features of wave erosion.

Answer 21

1. Wave erosion creates a notch at the bottom of the cliff, which, due to continued erosion grows into a cave.
2. Over time the cliff above the cave collapses as it is unsupported.
   3.The process repeats causing the cliff to retreat and increase in height.
   The gently sloping expanse of rock marking the foot of the retreating cliff is called a wave–cut platform, usually exposed at low tide.