Decomposition of the wave field into uniform Gaussian packets

The calculation shows decomposition of the wave field into uniform Gaussian packets (for theory see Zacek, 2006). The wave field to be decomposed are seismograms (common-shot gathers) of the "Marmousi model and dataset". The seismograms for shots 1 to 240 are in binary files 'seis-001.h@' to 'seis-240.h@' and can be found at http://sw3d.mff.cuni.cz/software/marmousi/marmousi.htm. To decompose and compose the seismograms run history file 'mar-gpax.h'

Notes on history file 'mar-gpax.h'

History file 'mar-gpax.h' for 240 shots repeatedly launches another history file 'mar-gpa.h' and generates PostScript plots of seismograms. History file 'mar-gpa.h' transforms input original Marmousi seismograms from binary to ASCII files, creates files with constant initial parameters R0 = -0.25E-6 sm-2 and Y0 = 0.25E-6 sm-2. Note that the initial parameters should be optimized and calculated according to Optimization of the Shape of Gaussian Beams but the current version of software does not enable it. The last step in history file 'mar-gpa.h' is calculation of the amplitudes of uniform Gaussian packets performed by program 'gpanal.for'. The program 'gpanal.for' is located in the directory '/data/mar'. To compile the program use command 'perl f.pl gpanal'.

Output files 'timesxxx.ps' are PostScript plots of seismograms to be decomposed, 'syntsxxx.ps' are plots of seismograms after composition and 'difxxx.ps' are plots of differences between seismograms. The output files of computation for shot 001 'times001.ps', 'synts001.ps' and 'dif001.ps' should be same as Figure 1, Figure 3a and Figure 4a in Zacek (2006). Output files 'amprxxx.out' and 'ampixxx.out' with real part and imaginary part of amplitudes of Gaussian packets are used as input in Gaussian packet migration in the Marmousi model.

References

Zacek, K. (2006): Decomposition of the wave field into optimized Gaussian packets. Stud. Geophys. Geod., 50, 367-380.