The spectral-element full waveform modeling method revolutionized earthquake studies by allowing scientists to accurately model seismic waves traveling through a heterogeneous three-dimensional Earth. With this technique, researchers can create global three-dimensional synthetic seismograms—the graphs created by a seismograph—and illuminate the structures of the Earth’s crust and upper mantle. However, for short-period waves used in detailed local structural studies, simulations using this state-of-the-art method require a prohibitive level of computation.
Now, in a technique that could become a standard for such research, Tong et al. have modified and extended this method for regional studies to allow the use of information from seismic arrays. The team’s approach combines the spectral-element method with a frequency-wave number technique. The authors demonstrate their hybrid approach by applying it to models of Tibet’s crust, accurately capturing interactions between seismic waves and crustal features. It was also successfully used to model variations in the Mohorovičić discontinuity, which divides Earth’s crust and mantle.
The team believes that they have created an essential tool for researchers studying teleseismic waves traveling through regions beneath seismic arrays. In the near future, the group will incorporate the technique into an open-source community software package so that other researchers can make use of it. (Geophysical Research Letters, doi:10.1002/2014GL061644, 2014)
—Eric O. Betz, Freelance Writer
Citation: Betz, E. O. (2015), Seismic wave modeling goes local, Eos, 96, doi:10.1029/2015EO023327. Published on 5 February 2015.