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San Andreas Fault Facts

San Andreas Fault Facts
The San Andreas Fault is a fault line that extends approximately 810 miles along the California coastline. The fault line is divided into three segments, each with different earthquake risk and different characteristics. The fault line section with the greatest degree of risk passes only 35 miles from Los Angeles. The San Andreas Fault was discovered in 1895 by a UC Berkley professor named Andrew Lawson. Andrew discovered the northern zone and the fault got its name after San Andreas Lake. It wasn't until the earthquake in 1906 that Andrew Lawson realized that the San Andreas Fault extended into southern California as well. In 1953 the conclusion that the San Andreas Fault could cause such an extensive earthquake was made by Thomas Dibblee, a geologist.
Interesting San Andreas Fault Facts:
The northern section of the San Andreas Fault runs from Hollister to Daly City, near Muscle Rock.
The central section of the San Andreas Fault runs from Parkfield to Hollister.
The southern section of the San Andreas Fault runs from Bombay Beach to Parkfield.
It is believed that the San Andreas Fault began forming about 30 million years ago in the mid-Cenozoic.
The San Andreas Fault located near Parkfield produces a 6 magnitude earthquake on average every 22 years.
In 2006 a study revealed that the San Andreas Fault has reached a stress level large enough to cause a magnitude 7 earthquake. They refer to an earthquake with a magnitude as greater than 7 as a 'big one'.
In 2008 a study was done that predicts an earthquake with a magnitude of 7.8 along the southern section of the San Andreas Fault would result in $213 billion in damage and likely about 1800 deaths.
In 2015 a study revealed that there is a 7% chance that an earthquake with a magnitude of 8 will occur in the next 30 years.
In 1857 the Fort Tejon earthquake, with a magnitude of 7.9, located near Parkfield, killed two people.
In 1906 the San Francisco earthquake, with a magnitude of 7.8, located near San Francisco, killed 3000 people.
In 1957 another San Francisco earthquake occurred, with a magnitude of 5.7
In 1989 the Loma Prieta earthquake, with a magnitude of 6.9, located near Santa Cruz, killed 63 deaths in San Francisco Bay's area.
An earthquake in 2004 at Parkfield was felt across California. It had a magnitude of 6.
The San Andreas Fault can be seen from space. It looks like a valley where the Pacific plate and North America plate meet.
Most of the population in California live on the west side of the San Andreas Fault.
Parkfield has become the center for earthquake research. In 2004 work began to drill a hole two miles deep into the San Andreas Fault. This drilling revealed that slippery clay may be the reason for some of the activity.
Magnitude 2 earthquakes occur near Parkfield regularly.
When a major earthquake occurs, there are usually several smaller earthquakes, called aftershocks that follow.
The magnitude rating of an earthquake is a measurement of how much energy is released. This is measured according to the Richter scale.


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