2.2 Landslides, Earthquakes & Tsunami's

1. A Landslide is when a mass of earth moves due to gravity.

2. Landslides are caused by heavy rainfall, earthquakes, or undercutting of banks and cliffs from waves or rivers.

3. Human actions can cause landslides due to buildings, roads or train tracks being made on hillsides as well as man-made hills.

4. Earthquakes are caused by the movement of the tectonic plates and are measured using the Richter scale.

5. The cause of earthquakes in Australia is intra-plate tension where movements occur along cracks and faults in the Earth’s crust.

6. In Australia, an earthquake or magnitude 5.5 or greater occurs every 15 months. Earthquakes have little impact on Australian communities as they are built in safe areas.

7. The Newcastle Earthquake:

·                     - Killed 13 people, injuring 120

·                      -35,000 homes and 3000 other buildings were moderately the seriously damaged

·                       - 70,000 buildings sustained minor damage

8. A landslide is when a mass of rock moves and an earthquake is when a plate moves.

9. A tsunami occurs when the ocean bottom moves forcing water to the surface creating waves.

10. Three events which will cause a tsunami are:

·         Earthquake

·         Volcano Eruption

·         Landslide

11. A tsunami is formed when a sudden shift in a plate causes sea water to be forced upwards. Waves move rapidly at speeds of 800km/h and soon hit land destroying everything in it’s path.

12. Three signs of a tsunami are:

·                        -An earthquake

·                         -A sudden retreat in sea level

·                         -A load roar

13. The Indian Ocean tsunami of 2004 was caused by an undersea earthquake between the Indo-Australian plate and Eurasian plate.

14. The Indian Ocean Tsunami took 20 minutes to be picked up by one of Australia’s 23 automated earthquake monitoring stations.

15. When a tsunami enters shallow water, it slows down and compresses making the waves bigger and stronger.

16. The United Nations responded by coordinating the development of a tsunami warning system for the Indian Ocean.

17. Ted Bryant is a geoscience professor and warns as of the possibility of a tsunami hitting Sydney from the Alpine Fault off New Zealand.

18. a.) The epicentre was located at 95’E and 5’N

      b.) i. India – 2hr

           ii. Africa – 7hr

           iii. Australia – 5hr

           iv. Tasmania – 9.5hr