Warm-Up Feb 4 Write What You Know! Write everything you know about the prompt below for five minutes, try for at least 3-4 complete sentences. What kind of dangers might you face during an earthquake? How can you prepare ahead of time for earthquake safety?

Chapter 2.2 Earthquakes & Seismic Waves Quakes & Waves Notes Chapter 2.2 Earthquakes & Seismic Waves

definition in own words facts pictures Quakes & Waves Notes (Chapter 2.2 Earthquakes & Seismic Waves) 2/4/2014 Major Key Term definition in own words Key Term definition in own words facts pictures Key Term

Seismic Waves Review Electromagnetic Waves: carry the energy of the stars and allow us to see what stars and other celestial bodies are made of Sonar Waves: carry the energy of sound and allow us to map the ocean floor Seismic Waves: carry the energy of earthquakes and allow us to see the inner structure of the Earth

(primary waves) (secondary waves) most destructive

Earthquakes Focus: area beneath surface where rock under stress breaks, the actual point of the earthquake Epicenter: the spot on the surface directly above the focus

Tracking Earthquakes P waves (primary) are faster than S waves (secondary) Geologists can use the difference in arrival times to determine distance to an earthquake’s epicenter

Geologists can tell distance, but not direction, of an earthquake from seismic waves monitored from one location If you monitor the same seismic waves from 3 or more locations, you can triangulate and find the epicenter!

Measuring Earthquakes Magnitude: the strength of an earthquake Richter Scale: rating of magnitude based on size of seismic waves There are other scales used by scientists, but Richter is most common