Los Angeles Basin

At some point during this period, a major earthquake hits California

Experts had been warning for years that it wasn't a matter of "if" – but "when" a major earthquake would strike the Los Angeles basin.* This particular quake is of sufficient magnitude to cause tens of billions of dollars' worth of economic damage, with much loss of human life. Thousands of buildings are destroyed and there is widespread damage to roads, bridges and other infrastructure.

References

"Geologists say it will be nothing like the United States has ever seen."
See Hurricane Sandy Will Be Dwarfed by an Earthquake, The Daily Beast:
http://www.thedailybeast.com/articles/2012/11/05/hurricane-sandy-will-be-dwarfed-by-an-earthquake.html
Accessed 1st January 2013.

"The Pacific Northwest has a long geological history of doing exactly what happened in Chile. There is an 80 percent chance the southern end of the fault off southern Oregon and Northern California could break in the next 50 years and produce a Megaquake."
See Truth or Hype: Is Seattle Really at Risk for a Devastating Earthquake?, Seattle pi:
http://blog.seattlepi.com/blaineweber/2010/03/23/truth-or-hype-is-seattle-really-at-risk-for-a-devastating-earthquake/
Accessed 1st January 2013.

Big Quake "Guaranteed" to Hit California by 2037, National Geographic:
http://news.nationalgeographic.com/news/2008/04/080414-AP-earthquake.html
Accessed 28th August 2009.