Earthquakes

Question 1

What are the 4 types of seismic waves?

Answer 1

Primary Waves
Secondary Waves
Rayleigh Waves
Love Waves

Question 2

What is an earthquake?

Answer 2

Release of stress built up within the Earth’s crust

Question 3

Describe primary waves:

Answer 3

Fast travelling, low frequency

Harmless but can travel through solids and liquids

Question 4

Describe secondary waves:

Answer 4

Half the speed of primary waves

Do little damage, cannot pass through liquids

Question 5

How is the strength of an earthquake measured?

Answer 5

Richter Scale
Moment Magnitude Scale
Modified Mercalli Scale

Question 6

What does the Richter Scale measure, scale?

Answer 6

Uses seismic waves magnitude to give a rating on scale from 1-9
Each number increase increases the magnitude 10 fold

Question 7

What does the Moment Magnitude Scale measure?

Answer 7

1.0-9.0 scale that measures energy release, area of fault and fault movement

Question 8

What does the Mercalli Scale measure?

Answer 8

Measures intensity and impact (uses words and Roman numerals

Question 9

Hazards created by earthquakes:

Answer 9

Ground shaking
Liquefaction
Landslides
Tsunamis/flooding

Question 10

What is liquefaction?

Answer 10

Soils (with high water content) lose their structure and become fluid when shaken

Question 11

Earthquake landforms:

Answer 11

Mountain chains (Himalayas)
Rift Valleys

Question 12

Positive impacts of living in tectonically active zones

Answer 12

+ Increased soil fertility due to lava
+ Economic activities (tourism)
+ Geothermal power
+ Range of useful gases produced

Question 13

Negative impacts of living in tectonically active zones

Answer 13

• Risk to life
• Property destruction
• Lava bombs/ tephra etc..