Earthquakes In Your State

Name: _________________________________       Date: _____________

Most earthquakes occur along the edges of Earth's tectonic plates where most faults are found. But faults may be found far from the plates' edges as well. Has your region ever been hit with strong earthquakes? The answer may surprise you.

In this activity, you'll take a look at the earthquake hazard risk where you live. You'll also visit the National Geophysical Data Center to find out about earthquakes that have occurred in your region over the past 350 years. Then you'll learn where earthquakes have hit in the United States in the past week.

1. To begin, view a USGS map of U.S. Earthquake Hazards. Look at the color scale to the right. Describe the earthquake hazard for your state.
   
   
   
   
2. Next, visit the U.S. Earthquake Intensity Database at the National Geophysical Data Center. Click on the U.S. earthquake intensity map of past earthquakes. How does the hazard risk (question 1) relate to the number and intensity of actual earthquakes in your region?
   
   
   
   
3. Where and when were the largest earthquakes to hit your region? What was their magnitude? To find out, return to the U.S. Earthquake Intensity Database. Scroll down to Earthquake Parameters. For beginning date, enter 1638. For ending date, enter 1985.
   
   
   
   
4. Continue scrolling to Earthquake Magnitudes. Enter a Minimum Magnitude of 5.0 and a Maximum Magnitude of 9.9.
   
   
5. Scroll to City and State Parameters to select your state.
   
   
6. Click Search Database at the bottom of the page. Your search will show all earthquakes of magnitude 5.0 or greater. The magnitude of each quake can found under the heading "Mag." The heading "MMI" stands for Modified Mercali Intensity, a measure of how strong an earthquake actually feels. What are the five strongest quakes (by magnitude) that hit your region? In the table below, enter the date, magnitude, MMI, and location (general region) for each.
   
   

   Date	Magnitude	MMI	Location

   
   
7. Have there been any earthquakes within 100 miles of where you live?
   
   
   
   
8. If so, when and where?
   
   
   
   
9. What were their magnitudes?
   
   
   
   
10. To see the most recent earthquakes in the United States, visit the USGS Earthquakes Hazard Program. Scroll to the Unite States map and click to enlarge it. Then go to the List of Recent Earthquakes. List the five largest earthquakes of the last week, including their location and magnitude.
    
    

    Date	Magnitude	Location