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how to find an earthquake
Tagged Under : facebook, geology
Over the weekend, a friend of mine from college asked, via Facebook, how geologists know where an earthquake was. To quote:
Hey Helen, would you please write a blog explaining how geologists can tell where an earthquake’s epicenter is? Are there things stuck in the ground all over the earth? How did they get there? Are they always watching? It kinda weirds me out to think about it.
I took a stab at explaining it on Facebook, based on my foggy memories of 10th grade earth science, then asked friend and fellow science writer Naomi Lubick, who actually has a degree in geology, if she could handle this one. And she did! Here’s her blog post: How to find an earthquake.
The short version: The earthquake sends out waves in all directions, and seismometers measure the waves. If you know when the waves arrive at each place, you can calculate where they came from. But go read Naomi’s post for more about earthquakes, like pretty maps and links and stuff.
So I posted this on Naomi’s blog too, but I’m curious now about the politics of seismic stations? Who controls them? Do they exist in “unstable” places like Burma or North Korea? Do they all cooperate? Are they “above” politics? Do the geologists visit each other?
Looks like she answered it over there. I’d forgotten about this data being used to monitor nuclear tests.