An earthquake the size of Turkey’s would bring devastation, death to Southern California

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A quake as strong as magnitude 8.2 is possible on the southern San Andreas fault and would bring disaster to all of Southern California simultaneously, with the fault rupturing from near the Mexican border to Monterey County.

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Among the impacts, the report found:

• The death toll could be among the worst for a natural disaster in U.S. history: nearly 1,800.
• Los Angeles County could suffer the highest death toll, more than 1,000, followed by Orange County, with more than 350 dead.
• Nearly 50,000 could be injured.
• Main freeways to Las Vegas and Phoenix that cross the San Andreas fault would be destroyed.
• Some 500,000 to 1 million people could be displaced from their homes.
• Southern California could be isolated for some time, with the region surrounded by mountains and earthquake faults.
• Major utilities such as gas, power and cell service would likely be severely compromised.

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California has been working to improve seismic safety rules for vulnerable buildings.

The ShakeOut scenario focused on unretrofitted brick buildings, brittle concrete buildings and so-called soft-story apartment buildings. Some cities including Los Angeles and San Francisco have been pushing retrofits for these types of structures.

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