Model with LENticular inclusion:  3-D boundary-value ray tracing by
two-parametric shooting.

Date: 2000, May 19
Written by Ludek Klimes

Two-point ray tracing for the point source:

    'len-crt.h'... History file running 'crt.for' to trace the
            two-point rays of the refracted P wave and then rewriting
            the resulting travel times at the given receivers by means
            of program 'crtpts.for' into formatted file 'len-ttr.out'.
            Input data files: 'len-mod.dat', 'len-src.dat',
            'len-rec.dat', 'len-crt.dat', 'codep.dat ', 'len-rpa.dat',
            and 'writall.dat'.
    'len-mod.dat'... Model.
    'len-rec.dat'... Names and coordinates of the receivers.
    'len-rpa.dat'... Data controlling two-point ray tracing to given
            receivers.

Boundary-value rays corresponding to the plane wave incident at the
bottom of the model:

    'lenb-crt.h'... History file running 'crt.for' to trace the
            two-point rays of the refracted P wave and then rewriting
            the resulting travel times at the given receivers by means
            of program 'crtpts.for' into formatted output file
            'lenb-rec.out'.
            Input data files: 'len-mod.dat', 'len-rec.dat',
            'lenb-rpa.dat', 'len-crt.dat', 'codep.dat ', 'writ.dat'.
    'lenb-rpa.dat'... Sample input data for the plane wave incident at
            the model bottom at 45 degrees.

Zero-offset boundary-value rays (exploding reflector):

    'lenz-crt.h'... History file running 'crt.for' to trace the
            two-point rays of the refracted P wave and then rewriting
            the resulting travel times at the given receivers by means
            of program 'crtpts.for' into formatted output file
            'lenz-rec.out'.
            Input data files: 'len-mod.dat', 'len-rec.dat',
            'lenz-rpa.dat', 'len-crt.dat', 'codep.dat ', 'writ.dat'.
    'lenz-rpa.dat'... Sample input data for the initial conditions for
            rays corresponding to exploding reflector.

Controlled initial-value ray tracing for the point source followed by
travel-time interpolation into a given grid of points:

    'leni-mtt.h'... History file running 'crt.for' to trace the
            rays of the refracted P wave, then running program MTT
            interpolating Multivalued Travel Times inside ray cells,
            program MGRD converting file with multivalued travel times
            into several files with singlevalued travel times, and
            program GRDPS plotting the numbers and values of the
            calculated travel times.
    'leni-crt.dat'... Input data for the CRT program.
    'leni-rpa.dat'... Data controlling initial-value ray tracing.