An earthquake can occur at any time of the year without warning when rock beneath the earth's surface suddenly breaks or shifts. Nearly every region of the United States is at risk for earthquake activity, with as many as 24 states categorized as "high" or "very high" risk by the U.S. Federal Emergency Management Agency (FEMA).
Worldwide, earthquakes occur every single day, sometimes as often as 1,000 times per day in the case of minor earthquakes, but many earthquakes are not strong enough to cause significant damage.
Damage usually occurs when an earthquake's magnitude is above a 4 or a 5 on the Richter magnitude scale. According to the U.S. Geological Survey National Earthquake Information Center, there were more than 4,000 earthquakes of magnitude 4.0 or higher in the United States from 2000 to 2009, with an average of more than 14,000 earthquakes of magnitude 4.0 or higher occurring worldwide each year.
According to FEMA, the U.S. states with a "very high" risk of earthquake activity include Alaska, California, Commonwealth of Northern Mariana Islands, Guam, Hawaii, Idaho, Montana, Nevada, Oregon, Virgin Islands, Washington, and Wyoming.
States with a "high" risk of earthquake activity include American Samoa, Arizona, Arkansas, Illinois, Indiana, Kentucky, Missouri, New Mexico, Puerto Rico, South Carolina, Tennessee, and Utah.
Many countries are considered high-risk areas for seismic activity, including Chile, Haiti, Mexico, India, Japan, Indonesia, China, Russia, Peru, New Zealand, and Iran, as well as many others.
Earthquakes are felt by the ground or floor moving, perhaps violently, and a rolling sensation like ocean waves may be felt if the center of the quake is not far away. Sometimes, a loud bang or a roaring sound is heard during an earthquake.
An earthquake registering a 4.0 or higher on the Richter magnitude scale can cause noticeable damage to buildings and infrastructures, with the following damage often occurring:
With careful preparation and planning, you can increase your chances of surviving an earthquake and help minimize damage to your home. The following tips can help you and your family to survive an earthquake, both before and after the earthquake activity reaches your area.
Before:
During (if inside):
During (if outside or driving):
After:
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