NAME

     ATTRIB  - module to calculate a  variety  of  user  selected
     seismic attributes on angle stacked data.


SYNOPSIS

     ATTRIB [ -Nntap ] [ -Ootap ] [ -as ] [ -ae ] [ -ai ] [ -rs ]
     [  -re ] [ -nanumangles (1,2, or 3) ] [ -attattrnum ] [ -V ]
     [ -? ] [ -h ] [ -ha ]


DESCRIPTION

     General

     Program ATTRIB allows the user to  calculate  a  variety  of
     sample  by  sample  seismic attributes on data that has been
     angle stacked. Data is expected in record  sequential  form,
     nonoverlapping  angle  stacks, and one trace for each angle,
     such as is generated by program  ANGST.   The  program  will
     handle one, two, or three angle data sets, and generates one
     attribute trace per input record.

     The following recon attributes are currently available:

     1) B0 Note: Needs a two or three  angle  bucket  input  from
     angst.

     2) B1 Note: Needs a two or three  angle  bucket  input  from
     angst.
              with angles out to a minimum of 15 degrees.

     3) B2 Note: Needs a two or three  angle  bucket  input  from
     angst
              with angles out to a minimum of 37 degrees.

     4) Bz=SIGN(B0)*B1 Note: Needs a two or  three  angle  bucket
     input
              from angst with angles  out  to  a  minimum  of  15
     degrees.

     5) Bp=B0*B1 Note: Needs a two or three angle bucket input
              from angst with angles  out  to  a  minimum  of  15
     degrees.

     6) Br=B1/B0 Note: Needs a two or three angle bucket input
              from angst with angles  out  to  a  minimum  of  15
     degrees.

     7) Middle angle stack - Near angle stack   Note: A two or
              three angle bucket input from angst needed.

     8) Large angle stack - Near angle stack
              Note: A three angle bucket input needed from angst.

     9) Large angle stack - Middle angle stack
              Note: A three angle bucket input needed from angst.

     10) Zero crossing angle in degrees.   Note: A two or
              three angle bucket input from angst needed.

     11) Restricted Gradient
            Two angle buckets: EE(middle angle)-EE(small angle)
            Three angle buckets: EE(large angle)-EE(small angle)

     12) dVp/Vp   Note: Needs a two or three angle bucket input
            from angst  with  angles  out  to  a  minimum  of  37
     degrees.

     13) dVs/Vs   Note: Needs a two or three angle bucket input
            from angst  with  angles  out  to  a  minimum  of  37
     degrees.

     14) dRho/Rho  Note: Needs a two or three angle bucket input
            from angst  with  angles  out  to  a  minimum  of  37
     degrees.

     15) dZp/Zp  Note: Needs a two angle bucket input
            from angst  with  angles  out  to  a  maximum  of  30
     degrees.

     16) dZs/Zs  Note: Needs a two angle bucket input
            from angst  with  angles  out  to  a  maximum  of  30
     degrees.

     17) d(Vp/Vs)/(Vp/Vs)  Note: Needs a two angle bucket input
            from angst  with  angles  out  to  a  maximum  of  30
     degrees.

     18) dF    Fluid Factor

     19) 1/B2  Contact Event  Note: Needs a  three  angle  bucket
     input
            from angst  with  angles  out  to  a  minimum  of  37
     degrees.

     20) Energy Envelope(small angle)  Note: Needs at least one
            angle bucket input from angst.

     21) Energy Envelope(mid angle)  Note: Needs at least two
            angle buckets input from angst.

     22) Energy Envelope(large angle)  Note: Needs a three
            angle bucket input from angst.

     23)  Energy  Envelope(mid  angle)  -  Energy  Envelope(small
     angle)
            Note:  Needs a two angle bucket input from angst.

     24) Energy Envelope(large  angle)  -  Energy  Envelope(small
     angle)
            Note:  Needs a three angle bucket input from angst.

     25) Enhanced Restricted Gradient.
            (EE(large angle) - EE(small angle)) * EE(large angle)
            Note:  Needs a three angle bucket input from angst.

     Parameterization

     ATTRIB gets its data and parameters from command line  argu-
     ments.

     Command line arguments

     -N ntap
          Enter the input data set name or file immediately after
          typing -N.  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 'vsp' stored on the 'b' disk.
          (Default = pipe input)

     -O otap
          Enter the output data  set  name  or  file  immediately
          after typing -O.  The output data set also requires the
          full path name (see above). (Default = pipe output)

     -as start angle
          Enter the angle, in degrees, that was used as  the  bin
          minimum  for the first stacked output trace. (Default =
          NONE)

     -ae end angle
          Enter the greatest angle, in  degrees,  that  was  con-
          sidered in stacking the input data.  This value was the
          bin maximum for the last stacked output trace. (Default
          = NONE)

     -ai angle increment
          Enter the angular width (in degrees)  of  the  stacking
          "bins". (Default = NONE)

     -rs start record
          Enter the actual number of the record on which to begin
          processing.   All  data  prior  to  this record will be
          skipped and not output.  (Default = the first record on
          the input data set)


     -re record end
          Enter the actual number of the record on which  to  end
          processing.   All  data  following  this record will be
          skipped and not output.  (Default = last record on  the
          input data set)

     -na number of angle buckets from ANGST
          This parameter should equal the number of angle stacked
          traces that were generated by ANGST.  Valid numbers for
          this parameter are 1,2 , or 3.  (Default = NONE)

     -att attribute number
          Enter the number corresponding  to  the  attribute  you
          want  calculated here.  Available attributes are listed
          above.  (Default = NONE)

     -V verbose printout
          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.

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

     -ha Enter the command line argument -ha  to  get  an  online
     list  of  currently  available attributes.  The program ter-
     minates after the help screen is printed.


AUTHOR

        David Woodruff EPTG ATTC


CONTRIBUTORS

        Mike Kelly    EPTG ATTC


COPYRIGHT

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













Man(1) output converted with man2html