NAME

     taupsamp - stretch NMO corrected tau-p records  to  constant
     angle traces

SYNOPSIS

     taupsamp [ -Nntap ] [ -Ootap ] [ -vvmod ] [ -V ] [ -? ]

DESCRIPTION

     taupsamp takes a set of NMO corrected plane wave traces from
     radonf  ...  -L  and  taupnmo  ...   and  stretches the data
     laterally to constant angle.  After the tau-p transform  and
     tau-p  normal  moveout  the  gathers  constant ray parameter
     traces, i.e. every sample of each trace corresponds  to  the
     same ray parameter for that trace. For some application like
     angle stacking we really need the gathers  in  the  form  of
     constant  angle  traces,  i.e.  every  sample  of each trace
     corresponds to the same angle for that trace.

     Given the ray parameters stored in the trace headers and the
     input primary stacking velocity we know from Snell's law the
     lateral distribution of angles at every sample.  Using  this
     information we can cubic spline stretch the gather laterally
     to overcome the angular focussing effect of the ray kinking.

     taupsamp gets processing controls  from  the  command  line.
     Reasonable  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 velocity model must be
     specified.


  Command line arguments
     -N ntap
          Enter the full path of  the  file  containing  the  nmo
          corrected plane wave data set.  If not specified, input
          is expected to be standard 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 constant angle  file.
          If  not  specified,  output  is expected to be standard
          output.  (default standard output )

     -v vmod
          Enter the full path of the file containing the velocity
          model.   This file is in SIS format and is RMS velocity
          versus two way travel time. Program will  stop  if  the
          velocity  model  file  is not given. The velocity model
          must have the same sample interval and number  of  sam-
          ples  as the trace data.  There is one velocity record,
          consisting of a single velocity-time  trace,  for  each
          seismic  record.   none ).  The header of the vmod file
          must be consistent with that of  the  data  file.   For
          this  purpose, the program velin (for interpolated mul-
          tiple velocity functions)  are  used  to  generate  the
          velocity file in SIS format.

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

     -?   Query mode.  With this flag, program.

BUGS

     Unknown:  this program is entirely experimental.  Good luck!

SEE ALSO

     radonf, taupnmo

AUTHOR

     P. R. Gutowski, TRC

COPYRIGHT

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