Alan Kafka
Weston Observatory
Department of Earth and Environmental Sciences
Boston College
(Originally Posted: April 27, 2012)
A few days ago, one of the huge springs on our garage door opener broke, with quite a big KABOOM!
It seems to me that this is a perfect example of the problem of earthquake prediction. Here’s what I see as the connection:
In the morning, the garage door repair guy (who happened to be there fixing something else) looked up at the spring and said, “That deformed spot in the spring is ‘metal fatigue’ – it might break in 5 minutes, or it might break in 10 or 20 years.” Then, two hours later, it broke! (Perhaps he disturbed the internal stress field while he was fixing something else?)
This seems to be a perfect analog of the Elastic Rebound Theory of earthquakes, and the phenomenon of Earthquake Triggering!
It also explains why we knew that an earthquake was lurking in Haiti, but we couldn’t tell when it would occur: The tectonic stresses were ready to be released in an earthquake, but nobody could tell if the earthquake would occur in minutes, in years, in decades, or in centuries…