donderdag 25 augustus 2011

What’s with all these earthquakes? | Bad Astronomy

What’s with all these earthquakes? | Bad Astronomy:

The Earth is trembling.


A magnitude 5.9 earthquake hit Virginia on August 23 at 17:51 UTC. Twelve hours earlier, a magnitude 5.3 quake shook southern Colorado (I slept through it; it was 360 km away). On August 20, a magnitude 7.0 hit off the coast of eastern Australia, and another magnitude 7.0 earthquake took place in northern Peru on August 24 at 17:46 UTC, just a few hours ago as I write this.


What gives? Are we seeing a swarm of related events? Is the Earth shaking itself apart?


It’s easy enough to think so. But our brains are wired in a way that makes them easily fooled (proof). What we need to do is not panic — always a good start — and think this through. Happily, we have an exceptionally good tool for this sort of problem: science. Well, science and a tiny touch of math.


Get me some stats, stat!


You need to look at the statistics, and not by coincidence the United States Geological Survey provides them. When you look at the chart, you see that ...