NAME

     opstd  - extracts the Tp scan and (optionally) the semblance
     data from output of opstf

SYNOPSIS

     opstd [ -Nntap ] [ -Ootap ] [  -O2stap  ]  [  -mfmutef  ]  [
     -vmvmin  ] [ -vxvmax ] [ -rsnrst ] [ -renred ] [ -nsmnsm ] [
     -W ] [ -F ] [ -? ]

DESCRIPTION

     opstd extracts the Tp scan and  (optionally)  the  semblance
     data  from  the  data set created by program OPSTF and saves
     them in separate data sets for analysis or input to  program
     opstcv for construction of velocity semblance panels.

     This program is one of six programs in a suite  of  programs
     for  creating,  processing,  and/or  analyzing optical stack
     results.  The other programs in the suite, and  their  func-
     tions, are:

     opstf  - create forward Tp scans and semblance panels

     opstk  - Extracts the stack and the velocity field from  the
     optical stack panels.

     opstcv - Resamples semblance panels created by program OPSTF
     from  constant  Tp  traces  to  constant (stacking) velocity
     traces for analysis.

     opstr  - create reverse of opstf

     XOS    - Provides graphical analysis  of  optical  stack  or
     semblance panels created by OPSTF.

  Command line arguments
     -N ntap
          Enter the input data set name or file immediately after
          typing -N unless the input is from a pipe in which case
          the -N entry must be  omitted.  The  input  to  program
          OPSTD  is  the multiplexed Tp scan and semblance panels
          output from program opstf.


     -O otap
          Enter the output data  set  name  or  file  immediately
          after typing -O.  This output file is not required when
          piping the output to another process.  The output  from
          program  OPSTD  consists of two new data sets. One data
          set contains the Tp scan panels and  one  contains  the
          semblance  semblance  panels.   The  latter data set is
          optional.

     -O2 stap
          Name of the SIS-formatted output  data  set  containing
          the  semblance  panels.   This  data  set  is optional.
          Default:  No semblance data set created.


     -mf mutef
          Enter  file  name  containing  mute  functions  to   be
          applied.   Functions are in the form of xsd picks keyed
          to record numbers.  Default: No mute function.

     -vm vmin
          Enter minimum velocity to  use  in  data.   Default  is
          minimum available.

     -vx vmax
          Enter maximum velocity to use in data.  Default is max-
          imum available.

     -rs nrst
          Enter start record number.  Default value is the  first
          record.

     -re nred
          Enter end record number.  Default value is last record.

     -nsm nsm
          Enter the number of points in  the  smoothing  (cos**2)
          function for the semblance.  This number corresponds to
          the semblance gate length for other programs,  such  as
          velspec  .   The  smoothing  function is applied to the
          semblance only.  Default: 0 (No smoothing  =  semblance
          gate of 1 sample)


     -W   If present weight stack with semblance

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

DISCUSSION

     Operations

     The data set output by program OPSTF contains both  Tp  scan
     traces  and  semblance  traces in each output record, multi-
     plexed in trace order.  The odd-numbered traces are Tp  scan
     traces  and  the  even-numbered traces are semblance traces.
     Other than program OPSTK, all other programs in the  Optical
     Stack  suite  expect  either  Tp  scan  traces  or semblance
     traces.  Program OPSTD demultiplexes this data  and  creates
     separate data sets which may be input to other programs.  If
     requested, the program will weight (multiply)  the  Tp  scan
     traces by the semblance traces before output.

REFERENCES

     de Bazelarie, E., 1988, Normal  moveout  revisited:  Inhomo-
     geneous  media  and  curved interfaces, Geophysics, Vol. 53,
     143-157.

     Arnold, Richard H. and Semaan, Mars E., 1990, Implementation
     of the Optical Stack Method, SEG Expanded Abstracts, Vol II,
     San Francisco.

BUGS

     unknown

SEE ALSO

     opstr, opstk, opstf, opstcv

AUTHOR

     Richard Crider, ES&S

COPYRIGHT

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