Adam Rifkin stashed this in Art!
From Reddit: When a magnitude 6.8 earthquake shook Olympia, Washington, in 2001, shopowner Jason Ward discovered that a sand-tracing pendulum had recorded the vibrations in the image above.
Seismologists say that the “flower” at the center reflects the higher-frequency waves that arrived first; the outer, larger-amplitude oscillations record the lower-frequency waves that arrived later.
“You never think about an earthquake as being artistic — it’s violent and destructive,” Norman MacLeod told ABC News. “But in the middle of all that chaos, this fine, delicate artwork was created.”