Earthquake

Question 1

What are the characteristics of plates?
What are the 2 types of plates?

Answer 1

1. Irregular in shape and have different thickness & sizes
2. lie and ‘float’ on asthenosphere
3. Oceanic plate; continental plate

Question 2

What are the 3 types of plate movements?

Answer 2

1. Plates move away / towards / past from each other

Question 3

Why do earthquakes occur?

Answer 3

1. plates move / compressed or stretched
2. Energy is built up & stored in the rock
3. When stored energy exceeds the strength of rock, it breaks
4. Energy is released in all direction as seismic waves

Question 4

Which are the 2 ways to describe an earthquake?

Answer 4

1. Using the depth of focus
2. Using the Richter scale

Question 5

What are the 3 types of earthquakes?
How to describe an earthquake using the depth of focus?

Answer 5

Shallow (0-70)/ intermediate (70-300)/ deep (>300) earthquake
shallower the focus —> lesser energy loss when seismic waves travelled to earth’s surface —> more destructive effects it will brings

Question 6

How to describe an earthquake using Richter scale?

Answer 6

1. Measured by the amount of energy released by an earthquake using seismometer / seismograph
2. Higher magnitude of an earthquake —> more energy released —> greater destruction, cause more Damages to lives and properties

Question 7

What is direct effects and indirect effects?

Answer 7

Direct effects (primary effects) : direct results caused by shaking of the ground
Indirect effects (secondary effects) : things that occurs as a result of the direct effects

Question 8

What are the direct effects and indirect effects caused by earthquakes?

Answer 8

Direct effects:
- building, road & bridges, dams along river collapse
- breaking of power lines, gas & oil pipelines

Indirect effects:
- Tsunami, floods, landslides, fires
- disruption to traffic, rescue work & delivery of emergency aid

Question 9

What are the preventive measures for earthquake?

Answer 9

1. Setting up monitoring and early warning systems
   
   • track and record the movement of seismic waves
   • alert people before an earthquake arrive at their location to give people time to protect themselves
2. Adopting careful land use planning
   
   • avoid development and building facilities with potential dangers in earthquake- prone areas (e.g nuclear power plants)
   • set up evacuation routes with adequate road signs to guide people to safe places asap (e.g open parks)
3. Constructing earthquake-proof buildings & structures
   
   • prevent buildings & infrastructure collapse
4. Educate people and have regular earthquake drills
   
   • increase peoples awareness —> reduce losses & injuries

Question 10

What are the remedial measures for earthquake?

Answer 10

1. Having well trained rescue teams
   
   • increase the number of survivors
2. Providing temporary shelters, emergency & financial aid
   
   • food —> increase the chance of survival after earthquakes
   • $ —> helps people rebuild their homes