NAME

     knimod - Kirchhoff Diffraction Stack Modeling

SYNOPSIS

     knimod [-Nntap] [-Ootap] [-VTnvel] [-ttmax] [-dtdtms] [-nap-
     nap]   [-edipedip]   [-mdipmdip]   [-rincrinc]   [-ismhismh]
     [-ismvismv] [-f1f1] [-f2f2] [-f3f3] [-f4f4] [-V] [-h] [-?]

DESCRIPTION

     knimod reads a depth migrated seismic dataset and a velocity
     model in depth and produces a normal incidence time section.

  Command line arguments
     -Nntap
          Enter the name of the reflectivity dataset after typing
          -N.  This is a USP-formatted dataset containing seismic
          amplitudes.  This dataset may be a pipe.

     -Ootap
          Enter the name of the output dataset after  typing  -O.
          This will be a USP-formatted normal incidence time sec-
          tion.  This dataset may be a pipe.

     -VTnvel
          Enter the input velocity field dataset name after  typ-
          ing  -VT. This is a USP-formatted velocity field, where
          sample values must be interval velocities entered as  a
          function  of  depth  V(x,z).  This dataset may NOT be a
          pipe.

     -dtdtms
          This value represents the sample rate  in  milliseconds
          for  the  output  dataset.   The  program  gives better
          results when a smaller sample rate is used.  The recom-
          mended value and default is 4 ms.

     -ttmax
          This value is in milliseconds and represents  the  max-
          imum  amount  of  time  for the output.  The default is
          4000 ms.

     -napnap
          This value represents the half aperture size in traces.
          The default is 150.

     -edipedip
          This value is in degrees and  represents  the  emergent
          dip angle for the rays.  The default is 50 degrees.

     -mdipmdip
          This value is in degrees  and  represents  the  maximum
          subsurface  dip  for  the  rays.   The  default  is 105
          degrees.

     -rincrinc
          This value represents the  surface  ray  increment  for
          shooting  rays. The default is 3, shoot rays from every
          third trace location.

     -ismhismh
          This value represents the number of times to apply a  3
          point  smoother to the velocity dataset in the horizon-
          tal direction. The default is 3.

     -ismvismv
          This value represents the number of times to apply a  3
          point  smoother to the velocity dataset in the vertical
          direction. The default is 3.

     -f1f1
          This value is the lower cut-off frequency of  the  tra-
          pezoidal  filter  to be applied to the input data.  The
          default is 3.

     -f2f2
          This value is the lower corner frequency  of  the  tra-
          pezoidal  filter  to be applied to the input data.  The
          default is 6.

     -f3f3
          This value is the upper corner frequency  of  the  tra-
          pezoidal  filter  to be applied to the input data.  The
          default is 30.

     -f4f4
          This value is the upper corner frequency  of  the  tra-
          pezoidal  filter  to be applied to the input data.  The
          default is 60.

     -h   Enter -h for online help. The  program  will  terminate
          after printing the information.

     -?   Enter this (or '-?' if you are running in  c-shell)  to
          get  online  help.   The  program  will terminate after
          printing the information.

     -V   Enter -V for a verbose printout.

BUGS

     None known.

AUTHOR

     N. D. Whitmore, Jr.

COPYRIGHT

     copyright 2001, Amoco Production Company
               All Rights Reserved
          an affiliate of BP America Inc.