Chapter 12, Section 1 Chapter 10, Section 2 Objective 1 Standards 3d. Students know why and how earthquakes occur and the scales used to measure their intensity and magnitude. Objective 1 Describe elastic rebound. Objective 2 Compare body waves and surface waves. Objective 3 Explain how the structure of Earth’s interior affects seismic waves. Objective 4 Explain why earthquakes generally occur at plate boundaries. Assessment Flap Book, Daily Quiz, Chapter Test Review Daily Bellwork, Science Starters, Standards Practice Movie on the Rock Cycle??

Key Terms Create a flashcard for each of the following terms (found on p.295 in your text book). P wave S wave Earthquake Shadow zone Elastic rebound Fault zone Focus Epicenter If you finish early, study your flashcards! Body wave Surface wave

INTERACTIVE Quickwrite: Describe what happens when a rock is thrown into a pond. How might this be similar to an earthquake?

Why earthquakes happen Earthquakes are movements of the ground caused by a sudden release of energy when rocks along a fault move. Rocks on both sides of a fault are pushed tight against each other. As stress builds up on one or both sides the rocks eventually and suddenly slip past each other. This causes the shaking of an earthquake.

Elastic rebound Elastic Rebound is the sudden return of elastically deformed rock to its undeformed shape.

Elastic Rebound Demo

Elastic Rebound Animation

Anatomy of an Earthquake The FOCUS = the location along a fault where the earthquake occurs. EPICENTER= the point on the Earth’s surface directly above the focus.

Quick Check!! What is the difference between the focus and the epicenter? ________________________________________________________________________ __________ ________ is the theory that rock returns to its original shape.

Seismic Waves As rocks slip along the fault lines the energy released as vibrations are called SEISMIC WAVES. Waves are like the ripples in a pond when you throw a rock in. 2 types of waves: Body Waves Surface Waves

Body waves P Waves S Waves Primary or Compression Waves Fastest, first waves to be detected Rock moves in a Back and Forth direction parallel to the direction the waves are travelling in Move through solids, liquids, and gases S Waves Secondary or shear waves Slower than P waves Rock moves side to side perpendicular to the direction in which the waves are traveling

Slinky Waves After activity have students reflect, compare/contrast in notebooks.

Where do Earthquakes occur? Earthquakes generally occur near tectonic plate boundaries. Convergent Oceanic Environments Divergent Oceanic Environments Continental Environments

Let’s Go Online… Fault Zones Fault zones are at plate boundaries Regions of numerous, closely spaced faults Faults are breaks in a body of rock (like a giant crack) Pull up actual USGS websiteNo Let’s Go Online…

Earthquakes Away From Plate Boundaries Earthquakes in places such as Missouri and Arkansas,occur because of ancient fault zones deep within the Earth’s crust.

Earthquake Engineering Activity Assessment Earthquake Engineering Activity Marshmellow Buildings?

Daily Quiz Put into Responders and/or project using SMART notebook. 3 Questions a day. Oral and on small papers??