The “Uniform California Earthquake Rupture Forecast” predicts that, as a whole, there is a 99% chance that California will have a major earthquake sometime within the next 3 decades. As dramatic as this is, I’m not sure that it’s news. Show me a study that predicts California breaking off from the 48 before Christmas, and you got my interest, but this? Meh.
The UCERF does, however, give specific likelihoods for cities having big quakes, information which will be useful for policy makers determining earthquake insurance rates, local building codes, and emergency planning. The Los Angeles area, for instance, has a 67% chance of a 6.7 or greater quake in the next 30 years, and the SF Bay area has a 63% likelihood of such an incident.
As a point of reference, a 6.7 magnitude quake has the energy equivalent of 5,600,000 tons of dynamite exploding underground. The Northridge earthquake had a magnitude of 6.7, and it injured thousands of people, and caused 12.5 billion dollars in property damage to the L.A. area.
As a point of reference for the probabilities, there is approximately 65% chance that I will purchase a bag of generic brand frosted miniwheats sometime in the next three days. There’s a 99% chance that I will see a golden retriever in that time frame. It is 100% likely that I will stick my finger in my nose in the next 30 seconds… done. Now you know how that kind of thing works.