Penn State - Earthquake Seismology

Earthquake Ground Motion Animations

Kuril Islands - 13 January 2007, 11:14:17 UTC (Mw = 8.1)

The animation shows the ground velocity in the 100-15s period range observed across the western United States by the EarthScope transportable array and generated by the 13 January, 2007 East of Kuril Islands great earthquake. Each circle represents a seismometer and the colors change to reflect variations in the signal amplitude crossing the array. For more information on the earthquake, click here. A plot of the displacement seismograms used in the animation is shown near the bottom of this page. For the animation, I use velocity seismograms corrected for instrument sensitivity only - this enhances the shorter period components of the signal.

Click here for a three-component animation of this event (ctrl-click to download an iPhone version or an ogg version).

Click here for more information on EarthScope; click here for information on the status of the transportable array.

Selected seismic wave traveltimes (from Phillip Crotwell's version of taup)

Gcarc = 54deg / Depth = 15 km
Phase Time   Slowness
P     563.32   7.307
PcP   628.20   3.817
PP    684.75   8.998
PP    692.67   9.954
PP    692.88   9.766
S    1019.45  13.526
ScS  1152.16   7.086
SS   1242.26  15.759
SS   1264.45  17.822
SS   1264.45  17.799

Vertical component displacement seismograms used in the animation. The animation illustrates the signal power (which is proportional to the square of the ground velocity). The two red lines show iasp91 P and PP times, and the two blue lines show the predicted arrival times of S and SS. Open image in separate window to enlarge.

Penn State Earthquake Seismology

Department of Geosciences