Bibb Quake From Huntsville Seismogram
Thanks to Steve Jones for this image… he writes:
“Hi James,
thought you might be somewhat interested in the event trace (attached GIF image) which I recorded this morning on my home-built seismograph here in Huntsville, of today’s M3.8 event with epicenter in Centerville. Note that it took about 30 sec. for the fast-moving P waves to reach Huntsville at 10:26:15 UTC, and almost a minute for the slower large-amplitude L waves to begin crossing my station at about 10:26:40 UTC.”
April 22nd, 2009 at 9:05 pm
It was caused by Nick Saban rolling over in bed.
April 23rd, 2009 at 12:26 pm
Very interesting, thanks for sharing! Steve, you said this is your home-built seismograph? Mind sharing a description of your set-up? It obviously works quite well!
April 23rd, 2009 at 1:18 pm
The design is based on the “Amateur Scientist” articles in Scientific American magazine many years ago; it is basically a short pendulum outfitted with capacitive sensor plates to develop the seismic signals that correlate with the earth movement. There is a classic article in 1975 that describes this “S-G” seismometer design. Also, a good website is http://psn.quake.net that has a wealth of data, construction plans, background information, etc. for a variety of seismic topics.