Section 4.3 -Distinctive Coastal Landscapes

Question 1

Describe a Concordant Coastline

Answer 1

A coastline with alternating bands of more and less resistant rock

Question 2

Describe a Discordant Coastline

Answer 2

A coastline with the same rock type all along the cliff

Question 3

Would bays and headlands be found on a concordant or discordant coastline?

Answer 3

Discordant coastline, bays are formed when there are increased rates of erosion on a section with less resistant rock

Question 4

Are coastal joints larger or smaller than faults?

Answer 4

Coastal faults are larger, they are both however formed from tectonic movement

Question 5

Give an example of a rock considered to be ‘more resistant’

Answer 5

Granite or limestone are two types of more resistant rocks

Question 6

What factors effect the energy of a wave?

Answer 6

Fetch (how far the wind has been blowing (uninterrupted), wind strength, and the time the wind has been blowing over this period of time

Question 7

Where do the large waves predominantly come from that hit the UK?

Answer 7

The south-west, the fetch is around 6000 km long (across the Atlantic) and winds can get very strong

Question 8

Describe the characteristics of a destructive wave

Answer 8

They have a much stronger backwash than swash. Therefore they remove much more sediment than they put on

Question 9

Describe the characteristics of a constructive wave

Answer 9

They have a stronger swash than backwash therefore put more material on the beach than they take away

Question 10

Describe the formation of a spit

Answer 10

Longshore drift moves sediment along the coastline. A dramatic change in the coastline would cause sand to build up behind the headland. Over time, more and more material is added forming the spit, and a salt marsh will build up behind it. In case of drastic change in the wind direction, the spit will form a hook on the end

Question 11

What is a coastal bar?

Answer 11

A spit joining two headlands together across a bay

Question 12

Describe traction ,saltation, suspension, solution

Answer 12

Traction is the movement of relatively large pebbles being rolled along the seabed. Saltation is where small pebbles are ‘hopped’ along the seabed. Solution is when tiny particles almost dissolved in the water are carried along in the water. Suspension is when small pieces of sand are carried along in the water.

Question 13

Define abrasion

Answer 13

Large rocks scraped along the seabed cause erosion

Question 14

Define attrition

Answer 14

Rocks are picked up by the ocean and thrown against a cliff causing erosion

Question 15

Define hydraulic action

Answer 15

Air and water force their way into cracks and break away at the rocks

Question 16

Define solution

Answer 16

Where naturally occurring chemicals in the sea (often from surrounding vegetation) dissolve certain types of rock such as chalk

Question 17

How does a beach form

Answer 17

Material eroded from headlands are carried along (because of LSD) and deposited and essentially trapped in a bay

Question 18

Define chemical weathering

Answer 18

Rainwater can be slightly acidic and reacts with the rock, and weakens the rock

Question 19

Define biological weathering

Answer 19

Tree roots dig into the rocks and break away at them. Humans or animals walk over areas prone to erosion and break away the rocks