Unit 4 - Restless Planet - Earthquakes

Question 1

What is an Earthquake?

Answer 1

An earthquake is the shaking and vibration of the Earth’s crust due to movement of the Earth’s plates.

Question 2

What is the focus?

Answer 2

The point where the waves started.

Question 3

Features of an Earthquake

Answer 3

Focus
Epicentre

Question 4

What is the epicentre?

Answer 4

The point directly above it on the Earth’s surface.

Question 5

What are seismic waves?

Answer 5

Stored energy released in waves.

Question 6

What is strain energy?

Answer 6

Stored rock that builds up into pressure.

Question 7

How are earthquakes measured?

Answer 7

Using a seismometer.

Question 8

How do seismometers record the shaking of the earthquake?

Answer 8

By looking at the waves on the graph.

Question 9

What is the magnitude?

Answer 9

The amount of energy an earthquake gives out.

Question 10

How do we measure the magnitude of an earthquake?

Answer 10

Using a Richter Scale?

Question 11

How do you read the Richter Scale?

Answer 11

An increase of 1 on this scale means the shaking is 10 times greater, and about 30 times more energy is given out.

Question 12

What damage can an earthquake do?

Answer 12

Buildings and bridges crack and topple. Roads Split Open.
Landslides may block roads.
Water mains burst - which means no water.
Transport comes to a standstill.
Gas piped fracture and electricity cables and torn down. These cause fires.
Cause Tsunamis.
Start fires.

Question 13

What impacts can be classified as primary impacts for earthquakes?

Answer 13

Buildings and bridges crack and topple.
Roads split open.
Landslides block roads.
Cooker and heater fall over causing fires.
Ceilings collapse.
Door Jam
Everything falls of shelves and tables.
Gas pipes fracture.
Electricity cables are torn down.
Water mains burst.

Question 14

What impacts can be classified as secondary impacts for earthquakes?

Answer 14

Earthquakes in the ocean floor can cause giant waves called tsunamis.
Transport comes to a standstill.
Fires from gas pipes rupture or cookers and heaters in homes.
No clean water.

Question 15

How do earthquakes happen?

Answer 15

Tectonic plates move; they strike.
Pressure and tension build up as the plates try to move.
Eventually, they jolt free and pressure and tension are released inside the crust as energy.
The energy passes through the earth’s crust as waves, an earthquake.