A: Natural/tectonic hazards

Question 1

Define natural hazard

Answer 1

A natural process which could cause death, injury or disruption to humans or destroy property and possessions.

Question 2

What are the two types of natural hazards

Answer 2

Meteorological

Geological

Question 3

What’s s geological hazard

Answer 3

Caused by land and tectonic processed

E’g. Volcanoes
Earthquakes
Landslides
Avalanches

Question 4

What’s a meteorological hazard

Answer 4

Caused by weather and climate

Tropical storms 
Extreme weather
Heatwaves 
Cold spells 
Climate change

Question 5

What’s a natural disaster

Answer 5

Natural hazard which has actually happened

Question 6

What are extreme events

Answer 6

They do not pose any threat to human activity and there not counted as hazards (drought in an unhabitated desert)

Question 7

What are different factors affecting hazard risk

Answer 7

Vulnerability
Capacity to cope
Nature of natural hazards

Question 8

What is hazard risk

Answer 8

The probability that a natural hazard occurs

Question 9

Explain vulnerability as a factor affecting hazard risk

Answer 9

More people in areas exposed to natural hazards the greater probability they will be affected by a natural hazard - hazard risk is higher

Question 10

Explain capacity to cope as a factor affecting the hazard risk

Answer 10

Natural hazards have to affect human activities to count as a hazard. The better a population can cope with an extreme event, the lower the threat

HICs are better coping

Question 11

Explain the nature of natural hazards as a factor affecting the hazard risk from a natural hazard

Answer 11

Type - the hazard risk from some hazards is greater than others
Eg tropical storms can be predicted and monitored giving people time to evacuate safely
But earthquakes happen very suddenly no warning

Frequency - some natural hazards occur more often than others increasing the hazard risk

Magnitude - more severe natural hazards cause greater effects than less severe natural hazards

Question 12

What is the earths surface made of

Answer 12

Huge floating plates that are constantly moving called tectonic plates

Question 13

What are the layers of the earth from the inner to the outer

Answer 13

Inner core
Outer core
Mantle
Crust

Question 14

What’s the core of the earth like

Answer 14

Ball of solid (inner) and liquid (outer) iron and nickel

Question 15

What’s the mantle like

Answer 15

Semi - molten rock that moves very slowly

Question 16

What’s the crust like

Answer 16

Divided into slabs called tectonics plates (they float on the mantle) plates are made of two types of crust — continental and oceanic

Question 17

What’s continental crust like

Answer 17

Thicker (30-50km) and less dense

Question 18

What’s oceanic crust like

Answer 18

Thinner (5-10km) more dense

Question 19

Why are the plates always moving

Answer 19

Because of convection currents in the mantle underneath the crust

Question 20

What’s it called where plates meet

Answer 20

Plate margins or plate boundaries

Question 21

What are the three types of plate margin

Answer 21

Destructive
Constructive
Conservative

Question 22

What are destructive margins

Answer 22

Two plates move towards each other

Oceanic meets continental. Denser oceanic is late if rocked down into the mantle and destroyed

Often creates volcanoes and ocean trenches (very deep sections of the ocean floor where the oceanic plate goes down)

Two continental meet. Plates collide. Ground is golden and froorced up creating mountain range

E.g. West coast of South America

Question 23

What are constructive margins

Answer 23

Two plates moving away from eachother
Magma (molten rock) rises from the mantle to fill the gap and cools, creating new crust

Eg mid Atlantic range

Question 24

What are conservative margins

Answer 24

Two plates moving sideways past eachother or moving in the same direction at different speed

Crust isn’t created or destroyed

Eg along west coast of USA

Question 25

What happens at destructive plate margins to form volcanoes

Answer 25

The oceanic plate goes under the continental plate because it is more dense. The oceanic plate moves down into the mantle where it’s melted and destroyed A pool of magma forms The magma rises through cracks in the crust called vents The magma erupts onto the surface (where it’s called lava) forming a volcano

Question 26

What happens at constructive margins to form volcanoes

Answer 26

Magma rises up into the gap created forming a volcano

Question 27

Where are volcanoes found

Answer 27

At destructive and constructive plate margins

Question 28

Where can some volcanoes also form?

Answer 28

Over parts of the mantle tht are really hot (hotspots) Eg in Hawaii

Question 29

Which plate margins do earthquakes occur at?

Answer 29

All three

Question 30

What are earthquakes caused by

Answer 30

Tension that builds up at all three plate margins

Question 31

How’s an earthquake formed at destructive margins

Answer 31

Tension builds up when one plate gates stuck as it’s moving down past the other into the mantle

Question 32

How do earthquakes form at constructive margins

Answer 32

Tension build up along cracks within the plates as they move away from each other.

Question 33

How do earthquakes from at conservative margins

Answer 33

Tension build up when plates that are grinding past each other get stuck

Question 34

What exactly is the earthquake during tension build up?

Answer 34

The plates eventually jerk past each other sending out shock waves (vibrations) which is the earthquake

Question 35

What do shock waves do

Answer 35

Spread out from the focus - the point in the earth where the earthquake starts. Near the focus the waves are stronger and cause more damage

Question 36

What’s the epicentre?

Answer 36

Point on the earths surface straight above the focus in an earthquake

Question 37

What are earthquakes measured with

Answer 37

Linen magnitude scale

Question 38

What does the moment magnitude scale measure

Answer 38

The amount of energy released by an earthquake (called the magnitude) It’s scale is logarithmic - so a magnitude 7 is ten times more powerful than a 6

Question 39

What is the magnitude of earthquakes which normally only cause slight damage to buildings although they can be worse in very built up areas

Answer 39

Magnitude 6 and below

Question 40

What size earth quakes cause major damage and deaths

Answer 40

Magnitude 7 and above

Question 41

Global distribution of earthquakes and volcanoes

Answer 41

...

Question 42

What are the two earthquakes we studied

Answer 42

Haiti | Japan

Question 43

When was the Haiti earthquake and what magnitude was it

Answer 43

January 2010 | Magnitude 7

Question 44

What were the primary effects of Haiti earthquake

Answer 44

Prison was destroyed releasing 4,00 imprisoners Buildings and homes destroyed 1-5 lost jobs Injuries or killed from collapsed buildings and falling debris

Question 45

Secondary impacts of the Haiti earthquake

Answer 45

250,000 buildings were destroyed meant that people couldn’t work, roads became blocked disrupting any rescue attempts, trade difficult Deaths of 250,000 people Cholera spread 1.3mill lost there homes Food rationed

Question 46

Where is Haiti?

Answer 46

19.19N 73.30W 72.5 longitude 18 Latitude Caribbean

Question 47

Impacts only from Haiti earthquake

Answer 47

``` Mag 7 250000 dead Mercali 8 No defences 280,000 destroyed buildings 4000 prisoners escaped 1.1 billion damage 1/5 lost jobs 1300 schools damaged 1.3mill homeless ```

Question 48

Impacts from Japan earthquake followed by tsunami 🌊

Answer 48

``` Up to 12000 peiple dead Magnitude 8.9 40m high wave 🌊 £200 billion damage Had defences but we’re destroyed Nucleur meltdown Shifted earth on its axis 10cm Mercali 9 Water reached 6 miles into land ```

Question 49

Impacts both on Japan and Haiti

Answer 49

``` Caused by earthquakes Affected major cities Had help from other places Natural hazards Houses/buildings + livelihoods destroyed Occurred just if coast Diseases from dirty water (cholera) ```

Question 50

Haiti is a Lic what were its responses to its earthquake

Answer 50

3/4 damages buildings were inspected + repaired 200,000 peiple recieved cash or food for public work World bank pledged $100 m to support reconstruction + recovery programmes

Question 51

Japan is a HIC what was its responses to its earthquake following with a tsunami

Answer 51

+ 100,000 soldiers deployed in search and rescue Blankets food and water distributed Specialised search and rescue teams flown in from overseas Exclusion zone set up around fukushima nucleur plant and peiple were evacuated from the area

Question 52

What was the earthquake in Japan and when and where is the area

Answer 52

The Sendai earthquake in Japan 201 Sendai is in the continent of Asia in the stat Thoku

Question 53

What was the cause of the Sendai earthquake

Answer 53

Tremors were result of a violent uplift of the sea floor 80mikes off the coast of Sendai where the Pacific tectonic plate slides beneath the plate Japan sits on. Tens of miles off the coast is Sendai, where the Pacific tectonic plate slides beneath the plate Japan sits on. Tens

Question 54

Monitoring volcanoes and earthquakes

Answer 54

Volcanoes Remote sensing - satellite detect heat and changes to the volcano shape Seismicity - seismographs record earthquakes Gas - instruments detect gases realeased as magma rises Earthquakes - generally occur without warning there’s some evidence of changes in water pressure, ground deformation and minor tremors prior to earthquakes

Question 55

How can you predict volcanoes

Answer 55

Based on scientific monitoring In 2010 an increase in earthquake activity beneath an ice cap in Iceland enabled scientists to make an accurate prediction about the eruptions that took place in March and April that year

Question 56

How can you predict earthquakes

Answer 56

Impossible to make accurate predictions about earthquakes due to the lack of clear warning signs

Question 57

How can you protect areas from earthquakes

Answer 57

Construct buildings and bridges to residue ground shaking Reinforce concrete columns strengthened by steel force Regular earthquake drills Construct tsunami walls

Question 58

How can you protect an area from volcanoes

Answer 58

Earth bankments or explosives to divert lava flows away from property

Question 59

How can you plan for volcanoes

Answer 59

Hazard maps show sangered places Used in planning to restrict certain land uses or to identify which areas need to be evacuated when an eruption is due

Question 60

How can you plan for an earthquake

Answer 60

Maps produces to show effects of an earthquake or identify those areas most at risk High - value land uses a.g. Hospitals can be protected in these vulnerable areas

Question 61

Why do people still live in areas at risk from tectonic hazards

Answer 61

They’ve always lived there don’t wanna naive from friends and family Employed in the area Confident in support from government after a tectonic hazard Think Severe hazards won’t happen again in area Soil around volcanoes is fertile because it’s full of minerals from volcanic ash and lava attracts farmers Volcanoes are tourist attractions - live/ work in tourist industry

Question 62

Management strategies can

Answer 62

Reduce the effects of tectonic hazards

Question 63

Monitoring tectonic hazards

Answer 63

Networks of seismometers and losers monitor earth movements, and can be used in early warning systems to give a small but vital amount of warning before a large earthquake occurs Scientist can monitor the tell-tale signs that come before a volcanic eruption, such as tiny earthquakes, escaping gas, and changes in the shape of the volcano (eg. Bulges in the land where magma has built up under it) all mean an eruption is likely

Question 64

Predicting tectonic hazards

Answer 64

Earthquakes cannot be realisable predicted but by monitoring movement of tectonic plates scientists can forecast which areas should be prepared for one to occur Volcanic eruptions can be predicted if the volcano is well-monitored, predicting when a volcano is going to erupt gives people time to evacuate this reduces number of injuries and deaths

Question 65

Predicting tectonic hazards

Answer 65

Buildings can be designed to withstand earthquakes eg by using materials like reinforced concrete or building special foundations that absorb an earthquakes energy Existing buildings and bridges can be strengthened (eg by wrapping pillars in steel frames) so they’re less likely to collapse under the weight of falling ash or due to shaking from an earthquake Automatic shutoff switches can be fitted that turn off gas and electricity supplies to prevent fires if an earthquake is detected by a monitoring system

Question 66

Planning for tectonic hazards

Answer 66

Future developments can be planned to avoid the areas most at risk from tectonic hazards Emergency services can train and prepare for disasters eg by practising rescuing people from collapsed buildings or setting up shelters this will reduce deaths People can be educated so that they know what to do if an earthquake or eruption happens Governments can plan evacuation routes Which reduces number of deaths by fires, pyroclastic flows or mudflows Emergency supplies like blankets, clean water and food can be stockpiled, if a natural hazard is predicted the stockpiles can be moved close to affected areas potentially