NAME

     znmo  - apply/remove gamma (see  MBS  documentation)  normal
     moveout correction

SYNOPSIS

     znmo [ -Nntap ] [ -Ootap ] [ -Gvmod ] [ -R ] [ -V ] [ -? ]

DESCRIPTION

     znmo takes a set of traces and applies the  gamma  dependent
     NMO  dynamic correction. The traces are usually CRPs derived
     from either 2D or 3D MBS. The  MBS  processes  result  in  a
     gamma  output  where  gamma  is  a perturbation of the input
     velocity field and is analogous to a  residual  NMO  correc-
     tion.  Hopefully  when the gamma NMO is applied the CRP pri-
     mary events will become flatter and can then be further fil-
     tered and/or stacked.

     znmo gets processing controls from the command  line.   Rea-
     sonable  defaults  are setup.  In addition, if no input file
     name is given, the binary trace data are expected to  be  on
     the  standard  input.  However, a gamma field must be speci-
     fied.

  Command line arguments
     -N ntap
          Enter the full path of the file containing the CRP data
          set.   If  not specified, input is expected to be stan-
          dard input.  If standard input  is  not  specified  and
          there  is  no  input,  e.g., program run in background,
          expect a termination. (default standard input )

     -O otap
          Enter the full path of the  output  NMO  corrected  CRP
          file.  If not specified, output is expected to be stan-
          dard output.  (default standard output )

     -G vmod
          Enter the full path of the file  containing  the  gamma
          field.   This file is in USP format and is gamma versus
          depth.  Program will stop if  the  gamma  file  is  not
          given. The gamma field must have the same sample inter-
          val and number of samples as the trace data.  There  is
          either  one  gamma field record, consisting of a single
          gamma-depth trace, for each seismic record, or a single
          gamma trace for the entire CRP data set.  The header of
          the vmod file must be consistent with that of the  data
          file.

     -R   If present remove residual normal moveout correction

     -V   Verbose mode. List command line  and  lineheader  input
          parameters.

     -?   Query mode.  With this flag, znmo will give a  descrip-
          tion  of  the  command line arguments and stop the pro-
          gram.

BUGS:

     none known at present.

SEE ALSO

     horvel3d, vi3d

AUTHOR

     Paul Gutowski, 1996 EPTG, pgutowski@amoco.com

COPYRIGHT

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