1. Earthquakes Understanding the inside of the Earth

3. THERE IS A MAJOR EARTHQUAKE, RIGHT NOW! WHAT WOULD YOU DO?

4. Watch the Earthquake and tsunami flood clip If you lived in an Earthquake zone what would you keep in your house to help you to survive? There may be fires from broken gas pipes, no electricity, blocked roads, floods. If you were the government what advice would you give to your people? What would you want scientist/engineers to do?

5. Predicting Earthquakes Scientist try to predict Earthquakes by measuring the movements of the Earth by using a seismograph There are seismograph stations all over the Earth

6. Primary and secondary waves P rimary waves come first They are the Push-Pull waves (longitudinal) They can travel through solids and liquids Secondary Waves come second and cause the major damage to buildings They are side to side waves (transverse) They cannot travel through liquids

7. Calculating the Epicentre To work out where the epicentre is you need at least 3 seismograph stations and you need to know the speed of the waves. Epicentre Station 1 Station 2 Station 3 10 seconds 5 Seconds 15 Seconds P-waves travel at 10km/s 150 km 50 km 100 km

8. The Shadow Zone How we know about the centre of the Earth P- wave shadow zone S-wave shadow zone

9. The inside of the Earth The inner core is made of solid iron, we know it is solid because the p-waves are heavily refracted because it is so dense The outer core is made of liquid iron, we know this because s-waves cannot travel through liquid and they suddenly disappear here.

10. Earthquake proof structures