Earthquakes

Question 1

How are earthquakes formed?

Answer 1

Earthquakes are formed through movement in the Earth’s crust (plate tectonics). The tectonic plates move along fault lines and build up pressure. If the plates slip, the energy is released in the form of waves. This causes shaking that is associated with an earthquake. The bigger the movement or the closer to Earth’s surface it is, the larger and stronger the waves will be.

Question 2

What is the centre of the earthquake called (where it starts)?

Answer 2

Focus

Question 3

What is the point directly above the focus called (on the Earth’s surface)?

Answer 3

Epicentre

Question 4

What do you call a person who studies earthquakes?

Answer 4

Seismologist

Question 5

What is the difference between the Movement Magnitude Scale and the Mercalli Scale?

Answer 5

The Movement Magnitude scale measures the strength/magnitude of the earthquake on a scale of 1 to 10, and the Mercalli Scale measures the damage the earthquake causes.

Question 6

Why are there fewer deaths as a result of earthquakes in more developed countries?

Answer 6

There are fewer deaths as a result of earthquakes in more developed countries because they have more resources and the houses are constructed to be earthquake resistant.

Question 7

Name four ways in which houses in more developed countries have been built to minimise the impact of earthquakes.

Answer 7

1. They have hollow concrete bricks designed to cause minimal damage if they fall from an earthquake.
2. They have roofs made from reinforced cement concrete (RCC).
3. They have foundations made of stone, made largely from the remains of destroyed houses.
4. They have reinforced steel corner pillars providing strength and flexibility.

Question 8

Why does it take longer to assist people in need in less developed countries?

Answer 8

It takes less developed countries longer to assist people because they are often under-resourced and less efficient.

Question 9

The impact of earthquakes can be reduced by putting safety measures in place. Name two of these safety measures.

Answer 9

1. Have a supply of bottled water and tinned food

2. Have equipment like tents and blanket on hand, ready to use if needed and easily accessible.

Question 10

Name 7 effects of earthquakes.

Answer 10

1. Injury
2. Disease
3. Displacement of people
4. Damage to infrastructure
5. Fires
6. Loss of life
7. Tsunamis

Question 11

Where do earthquakes appear most frequently?

Answer 11

Along plate boundaries

Question 12

What is the name of the scale used to measure the DAMAGE caused by an earthquake?

Answer 12

Mercalli scale

Question 13

What is the name of the scale used to measure the MAGNITUDE of an earthquake?

Answer 13

Movement Magnitude scale
or
Richter scale

Question 14

What do you call the ripples that are caused when plates slide past eachother?

Answer 14

Seismic Waves.