Contact: Shujuan Mao (maos@mit.edu) and Aurélien Mordret (aurelien.mordret@univ-grenoble-alpes.fr)
This MATLAB code package contains codes and test data for measuring seismic travel-time shifts in the time-frequency domain using the wavelet cross-spectrum analysis. MATLAB R2018a (or higher version) and the MATLAB WAVELET TOOLBOX are needed to run the codes.
Table of contents:
—— My_Wxspectrum_TO.m: The core function to calculate dt in the time-frequency domain by wavelet cross-spectrum analysis.
—— main_TO.m: An example of using My_Wxspectrum_TO.m on synthetic data. Plots come with one click.
—— synthetic_dvov_0.05percent.mat: Two synthetic waveforms for testing the codes. The synthetic seismograms are generated using velocity models of a homogeneous background superimposed by random heterogeneities. The perturbation between the current and reference velocity models is a homogeneous increase of 0.05% dv/v throughout the medium. (If interested, see Section 3.1 in the following reference for more details.)
Reference: Mao, S., Mordret, A., Campillo, M., Fang, H., & van der Hilst, R. D. (2020). On the measurement of seismic traveltime changes in the time–frequency domain with wavelet cross-spectrum analysis. Geophysical Journal International, 221(1), 550-568.