1. 2/13/15 Bell Ringer (L32) How are mid-ocean trenches formed?

2. Turn in your projects! Volcano Brochure Plate Tectonics Posters Are due today! Turn in bin!

3. Video: https://www.youtube.com/watch?v=JrBaiPN6A W8

4. R35: Anatomy of an Earthquake Earthquake: sudden motion or trembling of Earth caused by the quick release of energy in rocks -Occurs on FAULT lines -Pressure and stress build up in rocks and are released (resulting in the earthquake) -Rock can move from a few centimeters up to 2 meters during an earthquake

5. R35: Anatomy of an Earthquake

7. Wave: moves energy from one place to another Waves that travel through rocks are seismic waves.

8. R35: Anatomy of an Earthquake Quick write: Where does an earthquake start at? 2-3 COMPLETE sentences

9. R35: Anatomy of an Earthquake Focus point: the point where the rocks start to fracture The focus point is the origin (start) of the earthquake

10. L36: Anatomy of an Earthquake Epicenter: the point on the Earth’ s surface directly above the focus point *Earthquake waves start at the focus and travel outward in all directions *Earthquake waves do not originate at the epicenter

11. L36: Anatomy of an Earthquake

12. R36: Measuring Earthquakes P Waves: (primary waves) -fastest kind of seismic wave -first to arrive at a seismic station -Moves through solids and liquids (water or layers of earth)

13. R36: Measuring Earthquakes S waves: (Secondary waves) -travel slower than P waves -second to arrive at seismic station -can ONLY travel through solids

14. R36: Measuring Earthquakes

15. R36 Measuring Earthquakes

16. https://www.youtube.com/watch?v=gl4FvHKzAlU

17. R36 Measuring Earthquakes How do we measure earthquakes? Seismograph: machine that records seismic waves (p and s waves)

18. L37: Earthquake Scale Geologists have created scales for measuring the strength of earthquakes. Mercalli Scale: measures intensity of earthquakes based on how destructive it is on buildings and people (I- XII) I- Not felt XII-Extreme

19. L37: Earthquake Scales Richter scale: measures the magnitude of the earthquake based on how much energy it releases (1-10) 1- Not felt 10- Extreme

20. R37: Earthquake Research Project Research and earthquake (one you haven’t heard of before) Write a 1 page paper in your notebook Include: -Name of Earthquake -When and where it happened -What did it measure at? (richter/mercalli) -What was damaged? (explain) -Death toll? -Other interesting facts