Tectonic Hazards

Question 1

What is a natural hazard?

Answer 1

A physics event that threatens people or has the potential to cause damage, destruction or death.

Question 2

What is hazard risk?

Answer 2

The chance or probability of being affected by a natural event.

Question 3

What does TEA stand for in terms of distribution questions?

Answer 3

Trend
Evidence
Anomaly

Question 4

What are the two types of tectonic plates?

Answer 4

Continental and oceanic.

Question 5

What is heavier, oceanic or continental?

Answer 5

Oceanic is dense and thin, where as continental is light and thick.

Question 6

What evidence is there for continental drift?

Answer 6

Jigsaw theory - coastlines of continents fit together.
Fossil correlation between far apart continents
Rock and mountain correlation.

Question 7

Where do constructive plate margins occur? Give an example.

Answer 7

Occur between two similar plate boundaries. They pull apart.
Two oceanic - Between North American and Eurasian plates.

Question 8

What is formed at constructive plate boundaries?

Answer 8

In ocean - oceanic ridge forms where the magma is forced through the gap due to the pressure. E.g. Mid-Atlantic Ridge.
In land - rift valley.

Question 9

What type of volcano is formed at a constructive plate margin?

Answer 9

Shield volcano - flat volcanoes with runny lava.

Question 10

Where do destructive plate margins occur?

Answer 10

Occur between a oceanic plate and a continental plate.

Question 11

What happens at a destructive plate margin?

Answer 11

The oceanic and constructive plates converge and the oceanic subducts under the continental because it is more dense.

Question 12

How do earthquakes occur at destructive plate margins? Answer in terms of the ‘stick and slip’ process.

Answer 12

As the oceanic crust subducts under the continental crust, the oceanic crust gets stuck due to the friction between the plates. When this pressure is eventually released, a large earthquake can occur.

Question 13

What landforms form at destructive plate margins?

Answer 13

Fold mountains
Deep ocean trenches
Composite cone volcanoes where magma is forced up due to the pressure.

Question 14

Give an example of a destructive plate margin in the world.

Answer 14

Between the Nazca plates and South American plate. The Andes are an example of fold mountains and

Question 15

What is a conservative plate margin?

Answer 15

Two plates move parallel to each other, either at different speeds or in different directions.

The friction of these plates causes seismic activity to build up and earthquakes occur here.

An example is San Andreas Fault line

Question 16

When did L’Aquila occur?

Answer 16

6th April 2009

Question 17

What was the magnitude of L’Aquila?

Answer 17

6.3 on the Richter scale

Question 18

What were the primary effects of L’Aquila?

Answer 18

10,000 -15,000 buildings collapsed
308 people died
1,500 injured
Several buildings in the university were destroyed.
Many historical buildings and churches were destroyed.

Question 19

What were the secondary effects of L’Aquila?

Answer 19

House prices and rents increased due to lack of housing

Much of the CBD was cordoned off reducing business and income

Aftershocks triggered landslides and rockfalls causing damage

Cost of repairs estimated at 4 billion euros

Landslide and mudflow caused by a burst main water supply pipeline.

Question 20

What were the secondary effects of L’Aquila?

Answer 20

House prices and rents increased due to lack of housing

Much of the CBD was cordoned off reducing business and income

Aftershocks triggered landslides and rockfalls causing damage

Cost of repairs estimated at 4 billion euros

Landslide and mudflow caused by a burst main water supply pipeline.

Question 21

What were the short term responses to L’Aquila?

Answer 21

Train carriages and some of the president’s homes used as temporary shelter

£171,000 raised by British Red Cross

Italian Red Cross searching for survivors within an hour

Hotels provided shelter for 10,000 and 40,000 tents given out.

7 dog units

Declared a state of emergency which sped up international aid from US and EU.

Question 22

What were the long term responses to L’Aquila?

Answer 22

Free services - mobile, post, TV, mortgages, electricity and gas

University students exempt from taxes and university fees for 3 years.

552 million Euros granted from EU to begin rebuilding

Question 23

When and where did the Ghorka earthquake occur?

Answer 23

April 2015 - near Kathmandu, Nepal

Question 24

What magnitude was the earthquake at Ghorka?

Answer 24

7.8

Question 25

What were the immediate effects of the earthquake at Ghorka?

Answer 25

Over 8,500 deaths and over a million people made homeless

352 aftershocks

Over 500,000 homes destroyed

Reduced supply of food, water and electricity.

Question 26

What were the long term responses to L’Aquila?

Answer 26

Mortgages, TV bills, electricity, gas bills were suspended

Free public transport, and tax and university fee exemption for students

Free mobile calls

$552 million granted by EU for the rebuilding

Question 27

When and where was the Ghorka earthquake? What magnitude was it?

Answer 27

Kathmandu, Nepal in April 2015

7.8 magnitude

Question 28

What were the primary effects of the Ghorka earthquake?

Answer 28

Historic sites and temples destroyed eg. Dharahara tower

Over 8500 deaths and 500,000 homes destroyed

1 million people made homeless

Reduced supply of water, food and electricity

352 aftershocks

Question 29

What were the secondary effects of Ghorka?

Answer 29

Avalanche struck Mount Everest base camp killing 19 people

Landslides in Langtang valley destroying the village

Loss of tourism harming by the economy

3% more of population pushed into poverty

Food shortages due to rice being destroyed in homes

Helicopter crash killing 6 US Marines

Question 30

What were the immediate responses to Ghorka?

Answer 30

Hospitals were overwhelmed

Army called to help

Free phone calls

Helicopter rescue teams on Mount Everest

180 climbers rescued

Question 31

What were the long term responses to Ghorka?

Answer 31

$274 million aid committed to recovery in Nepal

Climbing permits extended so more tourism benefitting the economy

Historical sites reopened

Question 32

What are the 4 main reasons people live in areas prone to tectonic hazards

Answer 32

Agriculture - soil is naturally fertile and naturally irrigated (good at retaining soil)near volcanoes and rocks are rich in minerals

Mining - rising magma contains lots of minerals such as tin, silver, gold and diamonds can be found near volcanoes

Geothermal energy - heat energy can be harnessed from earth and used to provide energy to homes - Iceland uses 65% geothermal energy

Tourism - places such as Yellowstone National Park and Naples attract millions of tourists per year benefitting the economy

Question 33

What are the three Ps used for reducing the risk of tectonic hazards?

Answer 33

Prediction - tiltmeter which measures bulge in a volcano, seismograph lane monitoring sulphur dioxide activities

Preparation- furniture and objects fastened down, earthquake drills, awareness

Protection - retro fitting homes with fire resistant materials, buildings have rolling weights on top, shatter resistant glass