Here is a link for those who have never seen a post-earthquake disaster area.  Note that most collapsed buildings are “Unreinforced Masonry” (stone or brick) and “Nonductile Concrete Buildings” (the buildings that tend to “pancake” in earthquakes). In California we have somewhat improved the safety of unreinforced masonry buildings.  We have nonductile concrete buildings by the thousands, but we are not doing anything about them.  It appears that the Christchurch earthquake did not spare wood-framed houses either.  http://www.boston.com/bigpicture/2011/02/christchurch_earthquake.html