Earthquakes

Question 1

What is an earthquake?

Answer 1

Is a sudden shaking of earths crust

Question 2

What causes an earthquake?

Answer 2

Caused by two plates slipping past each other

Question 3

Fault line

Answer 3

Long deep cracks that separate different plates. As plates move they sometimes get stuck. Energy builds up and plates slip suddenly past each other

Question 4

Focus

Answer 4

Point underground where earthquake begins

Question 5

Tremors

Answer 5

Shockwaves or tremors move though earth shaking rocks as they go. This is earthquake

Question 6

Epicentre

Answer 6

Point on earths surface directly above focus

Question 7

Aftershocks

Answer 7

These follow the main earthquakes.

Often cause more damage because buildings are weakened

Question 8

What is a seismograph?

Answer 8

Instrument used to measure and record earthquakes

Question 9

Richter scale

Answer 9

Registers strength of earthquake. Scale ranges from 1-10. The higher the number the more destruction it causes. The Richter scale is a scientific measure to of earthquake magitude

Question 10

Mercalli scale

Answer 10

Is based on eyewitness observations. Ranges from 1-12. It was developed my Giuseppe mercalli

Question 11

When do tsunamis happen?

Answer 11

They happen when shallow earthquakes measures 7 or mor eon Richter scale

Question 12

What is a tsunami ?

Answer 12

Sudden vertical movement displaces the sea water

Question 13

Explain a tsunami

Answer 13

The energy from a the earthquake is transferred by waves through sea

Waves approach shallow coast line

The base causes water to retreat from land

Question 14

What is the base of tsunami called?

Answer 14

Trough

Question 15

What height can they rise to?

Answer 15

50m