Coast's

Question 1

what is mechanical weathering?

Answer 1

• a process that causes rock to crumble a break down of rocks
• In mechanical weathering, a rock is broken down without its chemical composition changing.

Question 2

what is one type of mechanical weathering?

Answer 2

freeze-thaw
it happens when:
1. the temperature alternates above and below 0 degree’s C (freezing point of water)

2. water enters rock that has cracks
3. when the water freezes the crack gets bigger which puts pressure on the rocks

4.when the water thaws it contracts which releases pressure on the rocks

5.this repeats and widens cracks and causes rocks to eventually break up

Question 3

what is chemical weathering?

Answer 3

the breakdown of rocks changing its chemical position

Question 4

what is a type of chemical weathering?

Answer 4

carbonation
1. rainwater has some carbon dioxide dissolved in it this makes it a weak carbonic acid

2. carbonic acid then reacts with rocks that contain calcium carbonate

e.g. limestone this means that the rocks dissolve in the water

Question 5

describe what mass movement is in detail

Answer 5

1. material shifts in a straight line along a slide plane (rock fall of/ tumbles off the side off a cliff)
2. material rotates along a curved slip plane
3. material breaks up along the bedding planes and falls down a slope

Question 6

how is a wave formed?

Answer 6

1. Wing blows over the surface of the sea and creates waves
   the greater the fetch (the distance the wind blows over the sea) the more powerful the wave
2. storms can create storm surges - temporary sea levels rises caused as strong winds push water on shore

Question 7

what type of wave erode the coast and what are the waves like?

Answer 7

• destructive waves erode the coast
  they have a:
• high frequency
• tall and steep
  their backwash is MORE powerful then swash
• material is removed from the beach

Question 8

what type of wave add material to the coast and what are the characteristics of the wave?

Answer 8

• constructive waves deposit material to the coast
  they have a :
• low frequency
• low and long waves
• their swash is MORE powerful then their backwash

Question 9

what are the three processes of erosion?

Answer 9

1. hydraulic action
2. abrasion
3. attrition

Question 10

describe the process of hydraulic action

Answer 10

waves crash against the rock and compresses the air within the cracks

this puts pressure on the rock and eventually the crack becomes larger as the process repeats

then eventually the rock falls off

Question 11

describe the process of abrasion

Answer 11

eroded particles in the water hit together and rub against the rock
removing small pieces

Question 12

what is the process of attrition

Answer 12

eroded particles in the water colide and break into smaller pieces and become more round in shape

Question 13

what does longshore drift do? and describe the process of it

Answer 13

• Long shore drift transports material along the coast
  1. waves follow the direction of the prevailing wing (most common winds)

2. the waves then hit the coast in the same direction of the prevailing wind
3. the swash carries material up the beach in the same direction of the waves
4. the backwash then carries material down the beach at right angles back towards the sea
5. this continues and looks like a zigzag motion

Question 14

what are the processes of transportation?

Answer 14

1. traction
2. suspension
3. saltation
4. solution

Question 15

describe what traction is

Answer 15

traction is when large particles like boulders are pushed along the sea bed by the force of water

Question 16

describe what suspension is

Answer 16

suspension is when small particles like silt and clay are carried along the water

Question 17

describe what saltation is

Answer 17

saltation is pebble sized particles bouncing along the sea bed by the force of water

Question 18

describe what solution is

Answer 18

solution is soluble materials such as limestone dissolving in the water and are carried along

Question 19

what is deposition? and describe the process of it

Answer 19

deposition is dropping material

1.occurs when sediment looses energy and slows down
2. coasts build up when the amount is deposition is greater then the amount of erosion
3. the amount of material that’s deposited on an area of coast increases when:
- their is lot’s of erosion elsewhere on the coast (more available material)
- lots of material is transported to the sea
4. constructive waves drop more material then they remove it
- their is more deposition then erosion

Question 20

what are the factors that influence the erosional landforms that develop on coastlines?

Answer 20

• rock type
• geological structures

Question 21

explain why rock type is a factor that influences erosional landforms

Answer 21

hard rocks like granite would take much longer to erode then soft rocks such as lime stone

Question 22

explain why geological structures is a factor that influences erosional landforms

Answer 22

rocks with lots of joints and cracks erode faster

Question 23

what are the two types of coastlines

Answer 23

concordant
discordant

Question 24

explain what a concordant coastline is

Answer 24

concordant coastlines have alternating of soft and hard rocks parallel to the coastline

Question 25

explain what a discordant coastline is

Answer 25

discordant coastline have alternating soft and hard rocks NEXT TO EACH OTHER (not parallel but in right-angles) to the coast