#Inappropriate language
29-Nov-89 22:46:38
Sb: #22967-#Inappropriate language
Fm: Jack Crenshaw 72325,1327
To: John M. Dlugosz 74066,3717
No, what I meant was: that convention center is very near the area of
greatest damage in the last quake.
BTW, I've been meaning to report to the folks over on CLM: The quake was
detected by our inertial lab tiltmeters here in Clearwater, Fla. Remember,
these are not seismometers, but part of our lab equipment. The instruments
show a tilt of about +/- 3 arc seconds, lasting over a period of about 1.5
hours (the waves disperse as they travel). Took about 30 minutes for the
first waves to arrive. If I do come to the conference, I'll bring a copy
of the graph.
These guys give a measure of an arc-second. Take a perfectly level board
17 feet long. Pick up one end, and lay a human hair under it. It's now
tilted by one arc-sec. The graphs would seem to imply that these meters
can easily detect angles on the order of 0.1 arc-sec or so.