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Great Basin National ParkWinter in the creek
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Great Basin National Park
Faults
nevada fault map

NV Seismological Laboratory

This fault map of Nevada shows the seismic potential of the state. The red dot is the location of Great Basin National Park.

Nevada is one of the most seismically active states in the country, ranking third after California and Alaska. To blame are the state's many faults, found at the base of almost every mountain range. The basin and range topography of the Great Basin is caused by movement along these faults. As these mountain ranges continue to grow through fault-block activity, earthquakes continue to occur. 

What is a Fault?
A fault is simply a fracture in the earth's crust. Movement along faults displace the rock layers on either side. The mountains in much of the Great Basin are large blocks of rock that have been uplifted and tilted by normal activity along fault lines. The basins between the mountains, on the opposite sides of the faults, have slipped downward, and have been filled in and leveled by erosion of the mountains above. Geologists refer to these landforms as "fault-block mountains." 

Earthquake Activity
Most earthquake activity occurs along the eastern Sierra Nevada mountains, on the Nevada's western border. The most powerful earthquake recorded in the state was a 7.6 magnitude quake that occured near Winnemucca in 1915.

While earthquakes don't occur at any regular interval, historically the frequency of an earthquake of magnitude 6 or higher has been one every 10 years, and for magnitude 7 or higher, one every 27 years.

 
historic earthquakes in Nevada

NV Seismological Laboratory

Earthquakes in Nevada from 1852-1988.

More Information
You can find maps of both recent and historic earthquake activity in Nevada at the U.S. Geological Survey's website.
Lexington Arch  

Did You Know?
Great Basin National Park is home to Lexington Arch, one of the largest limestone arches in the western United States. This six-story arch was created by the forces of weather working slowly over the span of centuries. This type of above ground limestone arch is rare.

Last Updated: December 13, 2007 at 17:17 EST