NAME

     regsys - module to correct multicomponent seismic data  into
     a regular system of orthogonal coordinates (right-handed, +z
     down), with a user-specified orientation.

     regsys assumes  that  the  seismic  data  are  vectors  with
     respect  to a system of coordinates which is fully described
     by  the  USP  headers  (mnemonics  MCTrSp,  MCList,  SrComp,
     RcComp,  SrXAzm, RcXAzm), possibly different for each source
     and receiver.   If  this  information  is  NOT  in  the  USP
     headers, use USP routine aps_usp.  Check the results of reg-
     sys by using usp_aqp.

SYNOPSIS

     regsys [ -Nntap ] [ -Ootap ] [ -Aazimuth-0 ]
     [ -V ] [ -? ]

DESCRIPTION

     regsys : This routine corrects multicomponent  seismic  data
     for  irregularities  of  source and/or receiver orientations
     (2D or 3D).  Such irregularities can arise if the lines  are
     crooked    (with    the    sources   always   shot   locally
     parallel/perpendincular to the line), or  just  because  the
     vibrator  trucks  go back-and-forth along the lines, instead
     of always being map-consistent.  Whatever  the  cause,  such
     irregularly-oriented data must be referred to a regular sys-
     tem of coordinates before being further processed as a  vec-
     tor.

     regsys gets both its data and its  parameters  from  command
     line  arguments.  These arguments specify the input and out-
     put filenames, the azimuth of the regular system of  coordi-
     nates,  and  a  verbose printout flag. You may use sticky or
     non-sticky arguments as you wish.


  Command line arguments
     -Nseismic_multicomponent-infile(s)
          Enter the filename for the  seismic  input  dataset(s).
          regsys  uses  the  multicomponent i/o library uspio; cf
          the man pages for prgmMC for details of data-set organ-
          ization.

     -Oseismic_multicomponent-outfile
          Enter the filename  for  the  seismic  output  dataset.
          regsys  uses  the  multicomponent i/o library uspio; cf
          the man pages for prgmMC for details of data-set organ-
          ization.


     -Aazimuth-0
          The coordinates of the output dataset may be given with
          respect  to  ANY  coordinate system (that is, +x may or
          may not be East).  Enter here the azimuth (in + degrees
          E  of  N) of the positive x-axis of the new coordinates
          (default is 90=East) , which will have +z pointed  DOWN
          (as the SEG recommends).

     -V   Enter the command line argument '-V' to get  additional
          printout.

     -? or -h
          Enter the command line argument  '-?'   or  -h  to  get
          online  help.   The  program  terminates after the help
          screen is printed.

DISCUSSION

     See Thomsen and Dellinger, Prepping  Multicomponent  Seismic
     Data  of Irregular Geometry, USP Note, June 1995 for further
     discussion.

BUGS

     None known.

SEE ALSO

     sps_aps(1)  aps_usp(1)  aqplot(1)   gthrplot(1)   usp_aqp(1)
     usp_sps(1)

AUTHOR

      Leon Thomsen (STAT x 7716; zlat02)

COPYRIGHT

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