imagine-america-without-los-angeles-expert-warns-southern-california-isnt-ready-for-major-quake

http://losangeles.cbslocal.com/2013/12/11/imagine-america-without-los-angeles-expert-warns-southern-california-isnt-ready-for-major-quake

http://en.wikipedia.org/wiki/Los_Angeles#Geology 

http://desertshapes.blogspot.ca/2014/02/diablo-canyon-and-central-coast-of.html

There is always the possibility of something big & ugly erupting.
http://www.infowars.com/beneath-yellowstone-a-volcano-that-could-wipe-out-the-u-s