Tectonic Hazards

Question 1

What are tectonic plates?

Answer 1

The earths crust is divided into slabs called tectonic plates that float on the mantle.

Question 2

What are plates made of ?

Answer 2

continental crust which is thicker and less dense.
oceanic crust which is thinner and more dense.

Question 3

How are plates moving?

Answer 3

due to the convection currents in the mantle.

Question 4

what is the place called where plates meet?

Answer 4

plate margins or plate boundaries.

Question 5

What are the three types of plate margins?

Answer 5

destructive, constructive and conservative.

Question 6

Destructive margins are where?

Answer 6

two plates are moving towards each other. the oceanic plate meets the continental plate, and the denser oceanic plate is subducted under and destructed, causing magma to rise. Volcanoes are formed here.

Question 7

constructive plate margins are where

Answer 7

two plates are moving away from each other. magma rises from the mantle to fill the gap and cools creating new crust.

Question 8

conservative plate margins are where

Answer 8

two plates slide past each other but at different speeds.

Question 9

At what plate margins do volcanoes occur at and what happens at these plate margins?

Answer 9

At destructive plate margins where the denser plate (oceanic) is subducted into the mantle where it melts. A pool of magma forms which then rises through the cracks in the crust . The magma then erupts forming an volcano.

At constructive plate margins the magma rises into the gap created by plates moving apart, forming a volcano.

Question 10

When a volcano erupts it emits …

Answer 10

lava, gases and ash.

Question 11

At what plate margins do earthquakes occur at and what happens at these plate margins?

Answer 11

At destructive plate margins where tension builds when one plate gets stuck as it moves past each other.

At constructive plate margins where tension builds along the cracks in the plates as they move away from each other.

At conservative plate margins where tension builds up when plates that are grinding past each other get stuck.

Question 12

Describe what happens when there is tension that builds up at plate margins.

Answer 12

The plates eventually jerk past each other sending out shock waves which are the vibrations.

Question 13

What is the focus in the earthquake?

Answer 13

This is the point in the earth where the earthquake starts.

Question 14

Where are the waves in the earthquake stronger?

Answer 14

near the focus, causing more damage.

Question 15

What is the epicenter and where is it located.?

Answer 15

The epicenter is the point on the earths surface straight above the focus.

Question 16

what are earthquakes measured by and what does it measure?

Answer 16

They are measured using the moment magnitude scale which measures the energy released by the earthquake (magnitude).

Question 17

What are some primary effects (caused by the ground shaking)

Answer 17

destroy buildings and infrastructure, and kill and injure people.

Question 18

What are some secondary effects (results in the ground shaking)

Answer 18

including fires and landslides.

Question 19

What are responses to earthquakes?

Answer 19

Responses include emergency care, support, and longer term reconstruction.

Question 20

How can wealth reduce the risk of a earthquake, give example?

Answer 20

Wealth can reduce risk as a HIC would be able to afford to build buildings that would not have a severe impact on the tectonic hazard. For example they could have shock absorbers so the buildings do not fall. However LIC would not be able to afford this, and are more likely to die from the earthquake. An example may be Chile and Nepal, where Chile had significantly less dead and injured with a bigger magnitude earthquake, but Nepal having numerous dead with a lower magnitude.

Question 21

What are some examples of immediate responses?

Answer 21

Search, rescue and short term air keeping survivors alive by providing medical car, food and shelter.

Question 22

What are some long term response’s?

Answer 22

Could be rebuilding and reconstructing homes, to restore normal life and reduce future risk.

Question 23

How could the immediate responses differ between Chile and Nepal?

Answer 23

Chile would have swift and effective responses by emergency services because of the money, and have basic needs.
Nepal would take longer, seeking aid globally and immigration because lack of shelter and service.

Question 24

How could the long term responses differ between Chile and Nepal?

Answer 24

Chile would have a quicker recovery time, with governments able to provide with reconstruction plans whereas Nepal would have have longer recovery times with needing support.

Question 25

Why do people still live at risky areas, where there is likely to be tectonic hazards?

Answer 25

They have always lived there, and moving could mean they leave jobs and family.
In wealthier countries effective monitoring and evacuation plans could minimize risk.
they may not have a choice because of money and food.
they may not have experience or knowledge of the risks associated.
there could be many benefits such as fertile soils rich mineral deposits and hot water.

Question 26

what management can reduce the effects of tectonic hazards? (4)

Answer 26

monitoring - laser monitor earth movements, can be used in early warning system to give a small warning before a large earthquake occurs
Prediction - earthquakes cannot be reliably predicted but scientists can forecast where they may occur by monitoring the movement of plates
Protection - new buildings can use reinforced concrete to absorb an earthquakes energy. They can strengthen roads and bridges.
Planning - future developments, emergency services prepared by practicing, people can be educated so they know what to do if something occurs, and prepare supplies like clean water and blankets.