How and Where Earthquakes Occur

More than 3 million earthquakes occur each year, or about one earthquake every 10 seconds. Most of these are small and go unnoticed. Each year, however, a number of powerful earthquakes occur. Because such earthquakes are among the most destructive of natural disasters, it is important to understand how and where they occur in order to prevent the loss of lives and property.

Most earthquakes result from the strain that builds up at plate boundaries or faults. This week, we will study the causes of earthquakes as well as how the energy released travels as waves through the earth.

Homework #9: Due Tuesday, April 7, 2009

Textbook: read pages 214-216, questions 1-5.

Spring Break starts this Thursday, April 9, 2009. ENJOY!

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