Listen, watch, learn: SeisSound video products

Debi L. Kilb, Zhigang Peng, David Simpson, Andrew J. Michael, Meghan Fisher, & Daniel Rohrlick

Published 2012, SCEC Contribution #1562

Sonification of seismic data is an innovative way to represent seismic data in the audible range (Simpson, 2005). Seismic waves with different frequency and temporal characteristics, such as those from teleseismic earthquakes, deep “non-volcanic” tremor and local earthquakes, can be easily discriminated when time-compressed to the audio range. Hence, sonification is particularly useful for presenting complicated seismic signals with multiple sources, such as aftershocks within the coda of large earthquakes, and remote triggering of earthquakes and tremor by large teleseismic earthquakes. Previous studies mostly focused on converting the seismic data into audible files by simple time compression or frequency modulation (Simpson et al., 2009). Here we generate animations of the seismic data together with the sounds. We first read seismic data in the SAC format into Matlab, and generate a sequence of image files and an associated WAV sound file. Next, we use a third party video editor, such as the QuickTime Pro, to combine the image sequences and the sound file into an animation. We have applied this simple procedure to generate animations of remotely triggered earthquakes, tremor and low-frequency earthquakes in California, and mainshock-aftershock sequences in Japan and California. These animations clearly demonstrate the interactions of earthquake sequences and the richness of the seismic data. The tool developed in this study can be easily adapted for use in other research applications and to create sonification/animation of seismic data for education and outreach purpose.

Citation
Kilb, D. L., Peng, Z., Simpson, D., Michael, A. J., Fisher, M., & Rohrlick, D. (2012). Listen, watch, learn: SeisSound video products. Seismological Research Letters, 83(2), 281-286. doi: 10.1785/gssrl.83.2.281.