shihaocui / dt-wavelet

Codes for measuring travel-time shifts by seismic interferometry in the time-frequency domain with wavelet cross-spectrum analysis.

MATLAB code for measuring seismic travel-time changes with the wavelet method

Contact: Shujuan Mao ([email protected]) and Aurélien Mordret ([email protected])

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.

UPDATE May 2021: A new package in PYTHON of this method can be found here: https://github.com/Qhig/cross-wavelet-transform/releases/tag/v1.0.0