coasts

Question 1

what is the definition of weathering?

Answer 1

the breakdown of rock in a place where it outcrops

Question 2

name 4 types of weathering

Answer 2

chemical freeze thaw/ mechanical biological exfoliation

Question 3

what is chemical weathering?

Answer 3

Acidic rain water and CO2 in the atmosphere combine to form carbonic acid. Causes calcium carbonate (limestone) to dissolve limestone is vulnerable due to its lines of weakness horizontal- bedding planes Vertical- joints carbonation is a type of weathering that changes CaCO3 to Calcium bi carbonate by dissolving limestone feldspur (in graphite) is vunerable acid rain causes erosion CHANGES THE ROCK

Question 4

what is freeze thaw?

Answer 4

break down of rock freeze thaw common in cold climates rains in day when it is warmer rain in small crack in rock at night it gets colder water freezes and expands in day it melts widens crack repetitive happens until rock breaks (scree)

Question 5

what is biological weathering?

Answer 5

tree roots can widen joints in rock burrowing animals can break down rock

Question 6

what is exfoliation (onion skin weathering)?

Answer 6

sun heats outer layers of rock faster than inside outer layers expand at night the cooler layers cool faster than the inside continuous until rock breaks away

Question 7

what is mass movement?

Answer 7

the downhill movement of material under the influence of gravity

Question 8

what role does mass movement have on coasts.

Answer 8

mass movement is the downhill movement of material under the influence of gravity. it causes the rock to retreat.

Question 9

what types of mass movement are there?

Answer 9

rock fall and land slide

Question 10

what is mass movement usually caused by?

Answer 10

weathering (mainly freeze thaw)

Question 11

what are the dangers of mass movement

Answer 11

rocks could land on someone block roads cause car accidents

Question 12

what is a wave?

Answer 12

a fast flow of water that heads to the shore

Question 13

what does the size of a wave depend on? and why?

Answer 13

its fetch because the wave will have a longer distance to travel if it has a bigger fetch therefore the wind will be able to increase the size for longer.

Question 14

what is fetch?

Answer 14

the distance of open water over which the wind can blow

Question 15

what are the two types of waves?

Answer 15

constructive and destructive

Question 16

what is a constructive wave?

Answer 16

powerful swash carry large amounts of sediment construct beaches, increase their size formed by distant storms that are 100s of km away well spaced apart powerfull strong swash weak backwash

Question 17

what is a destructive wave?

Answer 17

formed by storms that are near the coast destroy the beach weak swash strong backwash

Question 18

what is attrition?

Answer 18

pebbles and rocks get caught up in the current

they bang together

get smaller and rounder

Question 19

what is hydraulic action?

Answer 19

waves crash against rocks

air gets trapped in cracks in the rock

mini explosions (cavitations) occur

breaking down the rock

Question 20

what is abrasion?

Answer 20

wave picks rocks up and throw them at a cliff

breaks down cliff

rocks dragged along bottom of seafloor

make the rocky surface smooth

Question 21

what is soulution?

Answer 21

the dissolving of rocks such as limestone and chalk

Question 22

how is a wave cut notch formed?

Answer 22

abrasion and hydraulic action

certain size due to the fetch of the wave not being big enough to reach the top of the wave

Question 23

what is a headland?

Answer 23

narrow piece of land that projects from a coastline into the sea.

made from hard rock

Question 24

what is a bay?

Answer 24

a bay is a broad coastal inlet usally with a beach. made from softer rock.

Question 25

how are headlands and bays formed?

Answer 25

rock is perpendicular to the coast rocks are hard then soft then hard etc hard rock is more resistant (it can widthstand more erosion) so it erodes slowly weak rock is less resistant so it erodes faster than the hard rock forming headlands and bays a headland is narrow piece of land that projects from a coastline into the sea. made from hard rock a bay is a broad coastal inlet usally with a beach. made from softer rock. Also hydraulic action and abrasion doesnt erode at the same rate

Question 26

explain the formation of a sea stack

Answer 26

1. a crack in a joint in the rock (where it is weaker) due to hydraulic action and abrasion. 2. crack widened by erosion which causes a cave to form 3. caves erode to form an arch. takes place on a headland. 4. arch gets bigger at its base due to erosion untill the roof collapses. 5. a stack is created. a stack is an isolated part of a cliff. 6. due to hydraulic action and abrasion a wave cut notch is formed on the stack. wave cut nots is formed due to waves having a small fetch so they are not big enough to erode all of the stack. 7. when the roof becomes unstable it collapses to leave a stump. 8. this process takes 1000s of years

Question 27

what are the different types of transformation?

Answer 27

traction saltation suspension soulution

Question 28

order these: Suspension traction soultuion saltation

Question 29

what is traction?

Question 30

what is saltation?

Question 31

what is suspension?

Question 32

what is solution?

Answer 32

the tiny particles get dissolved such as less resistant rock like limestone and chalk. this is another type of erosion.

Question 33

Describe the process of longshore drift

Answer 33

* caused when prevailing wind blows in a diagonal direction * causes the waves to hit the beach at an angle * increases the fetch of the waves so bigger waves that throw rocks onto the beach. * swash hits the beach at an angle and due to gravity is pulled back at an angle of 90°. * causes rock to be transported down the coast

Question 34

what is longshore drift

Question 35

Explain the formation of a spit

Answer 35

* sudden change in direction of the coast * long shore drift (a deposition landform) continues to carry sediment in a straight line after the land has ended * salt marshed form behind a spit * a spit is an accumulation of land stretching from the shore to the sea * when the wind changes direction, the waves change direction so some material at the end of the spit may be forced inland to form a curved end. * cant form over a river esturary because the flow of water is too strong so it will move the sediments.

Question 36

why are sea levels rising?

Question 37

How does global warming contribute to sea level rise?

Question 38

how does glacial rebound contribute to sea level rise?

Answer 38

* the NW of UK used to be weighed down by ice * ice has melted causing it to rise by 2-3mm per year * causing the SE to sink

Question 39

how do storms and high winds contribute to sea level rise?

Answer 39

* due to the earth warming up there is more energy to drive atlantic depressions associated with gales and strong winds * leads to large destructive waves * waves capable of causing erosion in one night that is equivilant to many years of normal wave activity