Raw Helicorder Display showing both August 23 earthquakes
Last evening before I went to bed I noticed a small earthquake on my seismograph here in northeastern Ohio. The prominence of the surface phases indicated that it was some distance away but still its appearance suggested that it would still be the Americas. I estimated the time of occurrence and checked my email but found nothing reported there so I checked the USGS Earthquake Hazards site. The 4.6 Magnitude earthquake in Colorado was not in the set of magnitude and location parameters that I have defined to trigger notifications but it generated a very clean signal here in Ohio.
Magnitude 4.6 Colorado - August 22, 2011
This morning when I got up I did my customary quick check of the overnight emails on my iPod finding a Magnitude 5.3 earthquake in the same area. It also showed a very clean signal on my seismograph with all of the major phases showing quite well…a small P phase, the S, and both the Love and Rayleigh surface phases.
Magnitude 5.3 Colorado - August 23, 2011
Just felt one here at work in Kent – a little before 2 PM. Robin felt it down in Hartville – thought they dropped a big piece of pipe. We think it was the “big one (5.9) in central Virginia http://earthquake.usgs.gov/earthquakes/recenteqsus/Quakes/usc0005ild.php
Dave