Earthquakes

Question 1

How do earthquakes happen?

Answer 1

Two plates slide past eachother, and some parts get locked- tension builds
Suddenly, rock gives way causing the plates to lerch forward, releasing the tension
Waves of energy called seismic waves travel in all directions, the vibrations being the earthquake
As the rocks settle into their new positions, a series of aftershocks occurs

Question 2

What’s the distribution of earthquakes?

Answer 2

Uneven
Dominant linear pattern- west coast of South America
Isolated- Russia
Clustered- Greece and Turkey
Few in Africa

Question 3

What is the focus?

Answer 3

Where rocks break underground

Question 4

What’s the epicentre?

Answer 4

Directly above the focus on the surface- causes most damage

Question 5

What are the 4 types of seismic wave?

Answer 5

Primary- from focus
Secondary- from focus
Transverse- from epicentre
Longitudinal- from epicentre

Question 6

What are primary and secondary waves?

Answer 6

Primary- waves travel fastest, cause back and forth movement

Secondary- waves are slower, cause side to side movement

Question 7

What are transverse and longitudinal waves?

Answer 7

Transverse- waves cause side to side movement, less damage

Longitudinal- Waves cause up and down movement, lots of damage