2. 1.Causes: A.plate tectonics (elastic rebound theory)  faults “stick”  buildup of energy  when they slip lots of energy is released = EARTHQUAKE

3. B.glacial rebound theory  heavy glacier compresses ground  ground springs back up = EARTHQUAKE

4. 2.Earthquake terms: Focus : origin of energy release (deep underground) Epicentre : point on surface above the focus Liquifaction: when land turns to mud when shaken Tsunami: giant wave resulting from earthquake in ocean low in ocean, but fast moving friction slows it down as it nears shore  grows up to 80 m high!!

5. Diagram of science!

6. Aftershocks : minor faults nearby breaking loose follow major quakes Seismic waves : 3 types of waves emitted from earthquakes 1. P – wave (primary)  push / pull (compressional wave)  moves fast 2. S – wave (secondary)  side-to-side motion (“shear” wave)  moves more slowly 3. L – wave (Love)  rolling motion  last to arrive  travels along surface of Earth  most damaging

8. 3.Finding the Epicentre of an Earthquake: The distance between the P & S – waves increases as waves travel outward from the epicentre. How much time that passed between the detection of the P & S – waves can be used to determine how far away the epicentre was.

9. With 3 stations calculating distances to the epicentre of the earthquake, the epicentre can be pinpointed. With 3 stations calculating distances to the epicentre of the earthquake, the epicentre can be pinpointed.

10. Homework: Textbook Page 531, “Reading Check”, Textbook Page 531, “Reading Check”, Questions 1-3 Questions 1-3 Virtual Seismologist Activity Virtual Seismologist Activity 2 Earthquake Certificates must be printed / emailed with you name on them (can’t do San Francisco) 2 Earthquake Certificates must be printed / emailed with you name on them (can’t do San Francisco) http://nemo.sciencecourseware.org/VirtualEarthquake/VQuakeExecute.html http://nemo.sciencecourseware.org/VirtualEarthquake/VQuakeExecute.html http://nemo.sciencecourseware.org/VirtualEarthquake/VQuakeExecute.html