Relectivity Modelling Software

Associated Reading

Seismic modelling with the reflectivity method by Yongwang Ma, Luiz Loures, and Gary F. Margrave

Description

The software named 'reflectivity' is used to model seismic wave propagation in stratified earth models. Files provided for this release are located in the directory .../software/reflectivity. The main program is named 'reflectivity.m'. Subroutines are (by order called):

hanning_window.m	calculate tapering window for slowness and frequency
slowness.m	convert wave velocities into squared slowness
Rm_matrix.m	calculate the total reflection coefficient matrices between two interfaces
RT.m	calculate reflection and transmission coefficient matrices across an interface (called by Rm_matrix.m)
free_surface.m	calculate reflection coefficient matrices at the free surface
bessels.m	calculate Bessel's functions of the first kind (J0 and J1); this routine runs faster than Matlab's built in Bessel function script (besselj.m).

This code has been tested under MATLAB 7 (R14), running on both Microsoft Windows and Linux platforms.

As a function, 'reflectivity.m' requires three inputs, which are vectors and matrices. These variables can be loaded into the Matlab workspace from parameter files residing in the directory. 'reflecivity_test.m' demonstrates one way to do this. Three sample input files are given as examples; 1) model.dat, the earth model used in modelling; 2) geometry.dat, receiver offsets; and 3) parameter.par, the physical parameters used in modelling.

Useful References

Aki, K., and Richards, P. G., 1980, Quantitative seismology, Theory and Methods: Volume I: W. H. Freeman and Company.

Kennett, B. L. N., 1983, Seismic wave propagation in stratified media: Cambridge University Press.

Ma, Y., Loures, L., and Margrave, G. F., 2004, Seismic modelling with the reflectivity method: CREWES Research Report 16

Muller, G., 1985, The relectivity method: a tutorial: J. Geophys., 58, 153-174.