Warm-up BREAKING NEWS: PREPARE FOR AN EARTHQUAKE! Imagine that you have just received news that Charlotte is preparing for an earthquake. What would you do to prepare your home, family, and what resources would you need?

Follow-up: Did you think of these things? First aid kit and instruction booklet Plastic tarp or a small tent Emergency ("space") blankets and one sleeping bag for each family member  At least one gallon of bottled water per person, per day. For a 3-day supply, that adds up to three gallons of water per person  Enough canned or dried food for 3 days Can opener Flashlight (easily in reach) Battery-powered radio Spare batteries for everything (stored separately in waterproof bags) Toilet paper, soap, toothpaste and toothbrushes, and other personal supplies Multi-purpose dry chemical (Class ABC) fire extinguisher Any important medicine and supplies for infants, elderly people, and others with special needs

Earthquakes! SWBAT describe the anatomy of an earthquake SWBAT relate earthquakes to different types of plate boundaries.

North Carolina As a resident of Charlotte, NC as a insurance agent would you recommend a new homeowner to purchase Earthquake insurance? Explain your answer.

California As a resident of Charlotte, NC as a insurance agent would you recommend a new homeowner to purchase Earthquake insurance? Explain your answer. What have we studied in previous units would explain why California has more frequent and stronger Earthquakes.

Why does California see so many EQs? The San Andreas Fault!

Phases of an Earthquake Foreshock: any of the usually minor tremors commonly preceding the principal shock of an earthquake Earthquake: An earthquake is the shaking of the ground due to the movements of tectonic plates Aftershock: smaller earthquakes which are generated by the continued movement of plates and other materials after the main shock

Parts of an Earthquake Focus - the point within the Earth where the earthquake starts. It is the place below the earth’s surface where the rocks tear, come apart, or collide. Epicenter - location on the Earth’s surface directly above the focus. Surface waves move outward from the epicenter. Fault - the break in the crust where the earthquake occurs.

Types of Faults Strike-Slip, Reverse, Normal Each fault occurs at a different type of boundary!

Mini-Poster Draw a picture of each type of fault. (312) Label the following information on each picture: Fault, Hanging Wall, Footwall and make sure you included arrows indicating plate motion. Describe the force that is causing the plate to move. (Compression, tension, or shearing) Describe the type of plate boundary that is typically associated with each of these faults. (Convergent, Divergent, or Transform.)

White Board Question What type of plate boundary would produce a normal fault? Name the different types of stress that occur during Earthquakes. What type of faults should be most common at a spreading ocean ridge? Explain Draw and label the following: Hanging wall, Footwall, and Fault.

SEISMOGRAPH Instrument used by scientists to measure Earthquakes.

What do we use to measure earthquakes? Richter Scale – a scale from 1 – 10 that tells the magnitude (intensity) of an earthquake

Magnitudes and Energy of Earthquakes Annual Numbers of EQs As indicated in previous slide, as magnitude increases by 1.0, ground motion changes by a factor of 10. The change in energy with magnitude is even more dramatic. A change of magnitude by 1.0 corresponds to a change in energy released by a factor of 32! Notice the dramatic change in number of earthquakes of different sizes. Small earthquakes are MUCH more frequent than large earthquakes. However, because the energy changes by a factor of 32 with an increase of 1.0 in magnitude, large earthquakes account for most of the energy released in earthquakes. There are about 20 earthquakes of magnitude 7.0 or greater each year and these release 80% of all seismic energy. Earthquake Energy—To rephrase, for each unit of magnitude the amplitude of the waves increases by a factor of 10, but the duration also increases, so the energy released increases by a factor of 32! RESOURCE: See file “No. 3. How Often do Earthquakes Occur?” on website http://www.iris.edu/hq/publications/brochures_and_onepagers/edu What’s the message? MOST of the energy is released by around 20 magnitude-7 and larger EQs every year.

Modified Mercalli Scale Scale that measures an Earthquakes intensity (damage). Scale is in roman numerals from 1 – 12 or I to XII.

Earthquake Comparison Haiti 2010 Magnitude 7.0 220,000 Deaths 14 Billion in damage. Why were there more deaths in Haiti compared to Japan? Japan 2011 Magnitude 9 15,891 Deaths 300 Billion in damage. Caused a Tsunami

Elastic Rebound Theory

Why do earthquakes occur? Along a fault, energy builds up in a rock until it breaks…This release of energy causes an earthquake.

Elastic Rebound Theory Definition: the gradual buildup, and release of stress and strain, between tectonic plates which leads to earthquakes

Earthquake and Volcano Puzzle

Any last minute questions? Exit Ticket! Any last minute questions?

Exit Ticket What is an epicenter? What is the elastic rebound theory? Where is the focus in relation to the epicenter? Draw a diagram of the three types of faults we discussed in class today. Additional links to check out (for extra class time/early finishers): http://library.thinkquest.org/TQ0311162/anatomy.htm http://larryferlazzo.edublogs.org/2011/01/10/the-best-sites-for-learning-about-earthquakes/ http://teacher.scholastic.com/activities/wwatch/earthquakes/ http://www.sciencecourseware.com/virtualearthquake/VQuakeExecute.html