History file 'mgp-an.h' performs the decomposition of the common-shot seismograms into optimized Gaussian packets (for theory see Zacek, 2006). The wave field to be decomposed is represented by 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.cz/software/marmousi/marmousi.htm. Run history file 'mgp-an.h' to decompose and compose the seismograms.
The distributed version of the history file 'mgp-an.h' is set to compute decomposition for the shot 77 (at a horizontal coordinate of 4.9 km). It is the same shot used as example of optimization of the shape of Gaussian beams.
It is necessary at first to compute optimum initial parameters of Gaussian beams (see Optimization of the Shape of Gaussian Beams) and then run history file mgp-an.h. To run decompositions for other common-shot gathers you need to compute optimum initial parameters for each gather.History file 'mgp-an.h' launches another history file 'mgp-an1.h' for each shot, and generates PostScript plots of seismograms. History file 'mgp-an1.h' transforms the original Marmousi seismograms from binary to ASCII files, and calculates the amplitudes of optimized Gaussian packets using program 'gpanal.for', performs replacing of the smallest amplitudes of Gaussian packets by zeroes and computes composition of the approximated wave field using program 'gpsynt.for'. Programs 'gpanal.for' and 'gpsynt.for' are located in the directory 'data/mar'. Use command 'perl f.pl gpanal' and 'perl f.pl gpsynt' to compile the programs.
Output file 'ss077.ps' contains the PostScript plot of the original seismograms, 'ssc077.ps' contains the plot of seismograms after composition, and 'dif077.ps' contains the plot of differences between the seismograms. Output files 'a0r077.out' and 'a0i077.out', containing the real part and the imaginary part of amplitudes of Gaussian packets, are used as input in Gaussian packet migration in the Marmousi model.
To run the history file 'mgp-an.h' it is necessary to compile program 'gpsynt.for' with parameter MRAM=12000000. Include file 'ram.inc' is distributed with MRAM=4000000.
Zacek, K. (2006): Decomposition of the wave field into optimized Gaussian packets. Stud. Geophys. Geod., 50, 367-380.