Enlarge

These twisted trees in northwestern Tennessee were partially toppled during the New Madrid, Mo., quakes of 1811 and 1812. The trees resumed growing upright, as shown in this image taken about a century later.USGS

The most dangerous type of natural disaster, and also the most unpredictable, is the earthquake. In the first week of November 2011, people in central Oklahoma experienced more than two dozen earthquakes. The largest, a magnitude 5.6 quake, shook thousands of fans in a college football stadium, caused cracks in a few buildings and rattled the nerves of many people who had never felt a quake before. Oklahoma is not an area of the country famous for its quakes.

Although less expected than quakes in California and Alaska, these “mid-plate” tremors can do substantial damage. Some of the biggest known examples, centered over Missouri, rattled the eastern half of the United States two centuries ago. Today, scientists are still puzzling over what triggered past quakes in these places — and when similar ones might strike again.

Visit the new Science News for Kids website and read the full story: Eastern quakes can trigger big shakes

Enlarge

A magnitude 5.8 earthquake that struck central Virginia the afternoon of August 23, 2011, was felt from central Georgia to southeastern Canada. In many urban areas, including Washington, D.C., and New York City (Wall Street shown), people crowded the streets while engineers inspected buildings.Wikimedia/Alex Tabak

Enlarge

The New Madrid Seismic Zone is named for a town rocked by a series of earthquakes in 1811 and 1812. A network of seismometers deployed in the zone in the early 1970s has made estimates of quake size and magnitude there more accurate since 1974. The size of the quake points corresponds to the magnitude of the quakes; larger dots represent larger quakes.Quake points: USGS, Background: GEOATLAS/GRAPH-OGRE, adapted by Janel Kiley

Enlarge

Many people think just of California when discussing major quakes in the contiguous United States, but the Midwest’s New Madrid Seismic Zone and coastal South Carolina face similar threats.USGS

• Print
• |
• Comment
• |
• |
• |
• Tweet
• |