Waveview of 4508z2, 4508e2, 4508n2 (top):
The last 90 seconds of output from the ISGS seismometer. The green trace shows vertical motion, the blue trace shows horizontal motion in the East-West direction and the red trace shows motion in the North-South direction. At this “zoomed-in” scale, very small vibrations within the Natural Resources Building can be detected. During work-hours, the noise of the elevator is a common signal on these traces. The very long period surfaces waves from powerful, distant earthquakes can often be seen on this zoomed-in scale.
Waveview of 4508z4 (middle):
The last 90 minutes of output from the ISGS seismometer can be seen in this window. Current time in hours and minutes can be seen on the scale across the top. (This is Universal Time. Subtract 5 hours for Central Standard Time or 6 hours for Central Daylight Time). This trace shows vertical motion and is sensitive to moderate-sized earthquakes within central US or large earthquakes world-wide.
Waveview of 4508z6, 4508E6, 4508N6 (bottom):
The last 14 hours of output from the ISGS seismometer can be seen in this window. Current time in hours and minutes can be seen on the scale across the top. The green trace shows vertical motion and the blue trace shows horizontal motion. A filter has been applied to remove some of the long period vibrations. Vibrations from moderate to large earthquakes from around the world can be seen at this scale. Other vibrations, such as strong gusts of wind striking the building and freight trains passing on the nearby Canadian National tracks, can also be seen on these traces.
The ISGS seismometer is located in the Natural Resources Building on the
campus of the University of Illinois at Latitude 40.1011 N and Longitude 88.2290 W. This installation is designed for educational purposes and is not part of the national seismic network. The three component seismometer was manufactured by
Guralp Systems: guralp.com/product-range/40t-seismometers