NAME

     wedgeusp  - for given stack of reflection coefficients along
     a  wedge  of  grading  thickness  compute  amplitude, phase,
     reflection coefficient, and impedance responses

SYNOPSIS

     wedgeusp [ -Nntap ] [ -Ootap ] [ -nlnl ] [ -sisi ] [ -scsc ]
     [  -riri ] [ -tltl ] [ -thth ] [ -titi ] [ -flfl ] [ -fhfh ]
     [ -fifi ] [ -ngng ] [ -pdpd ] [ -X ] [ -V ] [ -? ]

DESCRIPTION

     wedgeusp takes a series of reflection coefficients contained
     within  a wedge of grading thickness and computes the ampli-
     tude, phase, reflection (time), and impedance responses. The
     grading  of  thickness is determined by the thickness incre-
     ment and the output of all the responses will have the  same
     number  of  traces, one per thickness increment. Thicknesses
     are defined in 2-way  time  units  and  frequencies  in  Hz.
     Reference:

     Marfurt, K.J and Kirlin, R.L., 2001,  "Narrow-band  spectral
     analysis  and  thin-bed  tuning",  Geophysics,  Vol.66, No.4
     (1274-1283).

     wedgeusp gets both its data and its parameters from  command
     line arguments.

  Command line arguments
     -N ntap
          Enter the input file  name  containing  the  reflection
          coefficients,  one  per  line.  These  will  define the
          layering within the wedge and will consist of alternat-
          ing top and bottom refl coef.

     -O otap
          Enter the output data base set name or file immediately
          after  typing  -O.   The output file names will have an
          appropriate suffix appended to  this  string:  apm.usp,
          phz.usp, rc.usp, imp.usp, respectively for the usp out-
          puts of amplitude,  phase,  refl  coef,  and  impedance
          responses.  For  the  xgraph option the comparable pre-
          fixes will be amp.xg, phz.xg, rc.xg, imp.xg

     -nl nl
          Enter the number of layers defined  by  the  reflection
          coefficient  file (should be the number of lines in the
          file / 2). No default.

     -si si
          Enter the sample interval  for  the  time  (refl  coef)
          response (ms or us). Default = 4

     -sc sc
          Enter the scale factor for the sample interval for  the
          time (refl coef) response. Default = .001 for ms

     -ri ri
          Enter the sample interval for  the  impedance  response
          (sec). Default = .0005

     -tl tl
          Enter the 2-way start time of the wedge  (sec).  Thick-
          ness increases. Default = 0

     -th th
          Enter the 2-way end time of the wedge (sec).  Thickness
          increases. Default = .2

     -ti ti
          Enter the 2-way time increment of the  wedge  thickness
          (sec), i.e. the time increment to be successively added
          to the starting wedge time thickness tl until the final
          thickness th is reached. Default = .001

     -fl fl
          Enter the starting frequency (Hz). Default = 0

     -fh fh
          Enter the ending frequency (Hz). Default = 100

     -fi fi
          Enter the frequency increment (Hz). Default = 1

     -ng ng
          Enter the fractional net to gross. Default = 1.0

     -pd pd
          Enter the pad to add to the top and bottom of the  max-
          imum wedge temporal thickness (sec). Default = 0.4

     -X   Enter the command line  argument  '-X'  to  output  all
          files  in  xgraph  format.  If using this you should be
          careful to limit the number of thicknesses so as not to
          choke xgraph.

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

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

EXAMPLE

     wedgeusp -N rc.dat -O junk -fl 0 -fh 100 -tl 0 -th 0.2 \
          -ti 0.001 -nl 4 -ng 0.5

     where the reflection coefficient model file rc.dat  contains
     the four (-nl 4) lines
          -0.1
          0.1
          -0.1
          0.1

     and where the frequencies go from 0 - 100  Hz  and  temporal
     thicknesses  go  from 0 - .2 secs in steps of .001 secs (201
     output traces).


     There will be four files created (in default usp format):
          junk.rc.usp - reflection response
          junk.imp.usp - impedance response
          junk.amp.usp - amplitude response
          junk.phz.usp - phase response

BUGS

     Phylum unknown. But  please  report  any  oddities  to  Paul
     Gutowski  or  Mike Bush. One problem yet to be sorted out is
     the sampling of the  responses  in  time  is  still  nearest
     neighbor. A more robust interpolation is being considered.

AUTHOR

     Mike Bush with mods by Paul Gutowski

COPYRIGHT

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