NAME

     picklay  - module to do overlay of  pick  event  on  seismic
     data

SYNOPSIS

     picklay [ -Nntap ] [ -Ootap ] [ -Ppfile ] [  -hwmnemonic]  [
     -Mmtype  ] [ -ampamp ] [ -nsnstr ] [ -nenetr ] [ -rsnrst ] [
     -renred ] [ -dtmul ] [ -fsisp ] [ -incspinc ] [ -V ] [ -? ]

DESCRIPTION

     picklay is a routine to overlay  information  from  an   xsd
     pick file to the corresponding seismic dataset.  The program
     performs  no  extrapolation  but  will  interpolate   within
     events.   The amplitude associated with the events is a com-
     mand line entry.  That amplitude will be placed at the  sam-
     ple  corresponding  to  the event time as well as the sample
     following.  The pick file may be in standard  xsd  pick for-
     mat  or may be a file of header values at the pick locations
     [this is the last option on the segment pull down menu].  If
     using  the latter be certain to detect TrcNum as your secon-
     dary output.  Usually RecNum would be used for record  iden-
     tification  in  this  file  but the user may chose any index
     [see below].  If you are using a standard  xsd  pick  format
     file   picklay   assumes  that  the indexing in that file is
     sequential record and sequential trace.

INPUT

     picklay gets both its data and parameters from command  line
     arguments.   These arguments specify the input, output, pick
     file, pick file type  flag,  amplitude  to  use  for  posted
     events,  start  and  end  traces, start and end record, pick
     file time unit override, the initial  shot  point  and  shot
     point interval overrides.  Verbose printout is available.

  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.  This input  file  should
          include the complete path name if the file resides in a
          different directory.  Example -N/b/vsp/dummy tells  the
          program to look for file 'dummy' in directory '/b/vsp'.

     -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  data
          set also requires the full path name (see above).

     -P pfile   [default: none]
          Enter the input pick file name immediately after typing
          -P.   The  input  file name also requires the full path
          name  (see  above).   The  pick  file  indexing  should
          correspond  to the trace header index chosen below.  If
          this is not true unpredictable results are sure to fol-
          low.

     -hw mnemonic   [default: RecNum]
          Enter the trace header mnemonic used to index the pick-
          file.

     -M flag    [default: pick]

           Enter : pick (pick file is a standard xsd pick file)
                   header (pick file is a file of  header  values
          at picks)

     -ns nstr    [default: first trace]
          Enter start trace.

     -ne netr    [default: last trace]
          Enter end trace.

     -rs nrst    [default: first record]
          Enter start record.

     -re nred    [default: last record]
          Enter end record.

     -dt mul     [default: 1]
          Enter pick file time unit multiplier.  If unused,  pick
          file times will be unaffected.

     -fs isp     [default: option not used]
          Enter the record number to be  used  in  place  of  the
          first pick file record value.

          WARNING ...... if you use this  option  you  must  also
          include -inc.

     -inc spinc  [default: option not used]
          Enter the shot point increment  to  use  between  input
          pick segments (see -fs).

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

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

BUGS

     It is impossible to check for all possible errors that could
     be  present in the users xsd pick or header file.  There are
     policemen in the code to detect the most  common  of  these,
     however  there  will  always be a way to crash this routine.
     It will not crash in the sense of throwing a  core  but  may
     not  honour  your  events  as  picked.   When picking events
     within records make sure that you don't hang a pick  over  a
     record  boundary.   This is the most common error and is the
     hardest to recover from since it is not always obvious  what
     the  user intended to do.  Always begin your picking session
     by clearing the xsd pick register.  This  assures  one  that
     there are no picks left over from a previous image that will
     cause mysterious problems down the line.  Also  if  you  are
     using  the header file option [the default] remember to also
     output from  xsd  a standard pick file of your picks so that
     you  can  reload them later if desired.  You cannot reload a
     header file to  xsd .  This file  is  an  output  of  header
     values  at  the  pick locations only.  It is NOT a true pick
     file.

AUTHOR

     Paul G.A. Garossino APR:3932

COPYRIGHT

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